CARDIOVASCULAR (13%) Flashcards
HYPERTROPHIC CARDIOMYOPATHY
HOCM = hypertrophic obstructive cardiomyopathy
= broad term used to describe disease of the myocardium
cardiomyopathy = “heart muscle disease”
Primary cardiomyopathy = disease of heart muscle develops on its own
Secondary Cardiomyopathy = when cardiomyopathy develops in order to compensate for other diseases such as HTN or valve diseases (aortic stenosis)
Hypertrophic = heart muscle walls become thick , heavy, and hyper-contractile ==> essentially muscle becomes much larger - as new sarcomeres are added in parallel to each other
Usually the LV is most affected with hypertrophic cardiomyopathy == however, the hypertrophy is ASYMMETRICAL, meaning the interventricular septum grows larger relative to the LV free wall (border side)
LEADS TO
1) less LV space due to wall hypertrophy –> less blood can fill into the LV
2) LV muscle becomes more stiff / less compliant –> can’t stretch out as much –> also leads to less filling
With less filling of LV –> less blood pumped out from LV to the body = decreased SV (stroke volume - the volume of blood pumped from the left ventricle per beat) –> Heart Failure (when heart fails to pump enough blood to the body)
Hypertrophic cardiomyopathy has a thick interventricular septum that is too close to the anterior mitral leaflet, which causes outflow obstruction.
HYPERTROPHIC CARDIOMYOPATHY = A TYPE OF DIASTOLIC HEART FAILURE (because the decreased filling of the LV occurs during diastole)
Hypertrophic cardiomyopathy is classified as a diastolic dysfunction.
In some cases, the left interventricular septum enlargement gets in the way of the outflow tract of blood through the aortic valve
- > this causes the velocity of blood to increase as it goes through a narrowing to get to the aortic valve
- > this creates obstruction
- > mitral valve leaflet may pull down to try and decrease the velocity ===> ** VENTURI EFFECT **
- which is why it is sometimes called a HOCM (Hypertrophic OBSTRUCTIVE Cardiomyopathy)
MURMUR
⦁ *** CRESCENDO - DECRESCENDO SYSTOLIC MURMUR = anytime blood is going through a narrowing - gets louder as blood is first rushing out, then gets softer (also seen in Aortic Stenosis)
- murmur best heard at LEFT LOWER STERNAL BORDER / APEX - radiates to the axilla
The intensity of the murmur can change, however, depending on the intensity of the obstruction
⦁ If patient Squats or does Handgrip = the systemic vascular resistance increases => venous return increases = makes it harder for blood to be ejected => increases afterload ==> more blood in the LV that helps to stretch it out –> less obstructed => diminished murmur
⦁ If patient Stands or does Valsalva maneuver = venous return decreases ==> decreases preload (LV pressure after diastole, before systole) => less blood in the LV to stretch it out –> more obstruction => murmur intensity increases
**MURMUR = LOUDER WITH VALSALVA MANEUVER **
** HARSH SYSTOLIC CRESCENDO-DECRESCENDO MURMUR ** - best heard at LLSB (left lower sternal border)
DECREASED MURMUR INTENSITY ⦁ squatting ⦁ handgrip ⦁ laying supine = increased venous return - increased LV volume preserves outflow more, as the increased fluid pushes the septum out of the way and decreases SAM of the mitral valve (systolic anterior motion)
INCREASED MURMUR INTENSITY
⦁ standing
⦁ Valsalva maneuver
⦁ dehydration
⦁ ** BIFID PULSE ** = may have 2 pulses felt - due to venturi effect of mitral valve leaflet moving closer to interventricular septum hypertrophy -> increased obstruction mid-systole
DECREASED COMPLIANCE
- with larger muscle mass, the ventricle becomes less compliant / decreased ability to stretch when filled with blood
==> may hear S4 HEART SOUND = sign of LVH
S3 heart sound = may be pathological or normal. Can occur normally in children, pregnant women and athletes, however, can also be a sign of heart failure
- S3 occurs right after S2 = delayed closure of aortic valve
S4 = almost always abnormal - can occur with aortic stenosis, HTN, and now HOCM
- occurs before S1 = produced by blood striking the hypertrophied LV
An S4 heart sound is commonly associated with hypertrophic cardiomyopathy.
- may have mitral regurgitation
- may have S4
- may have S3
- may have ** PULSUS BISFERIENS ** (bifid pulse)
ISCHEMIA
⦁ increased heart muscle requires more oxygen, but hypertrophied LV has decreased amount of oxygenated blood —> develop dangerously fast arrhythmias
===> HYPERTROPHIC CARDIOMYOPATHY = MC CAUSE OF SUDDEN DEATH IN YOUNG INDIVIDUALS, ESPECIALLY YOUNG ATHLETES
typically asymptomatic until sudden cardiac death
or have symptoms only with exercise
SYMPTOMS
⦁ dyspnea** = MC initial complaint (90%)
⦁ syncope
⦁ angina / exertional chest pain (75%)
⦁ fatigue
⦁ arrhythmias (Afib, VT, VF) - palpitations, syncope, sudden cardiac death (ischemia)
Hypertrophic cardiomyopathy can cause syncope during exercise and may lead to sudden death in young athletes due to VENTRICULAR ARRHYTHMIA
PATHOPHYSIOLOGY
- Subaortic outflow obstruction - narrowed LV outflow tract secondary to
1) hypertrophied septum + 2) systolic anterior motion of mitral valve / papillary muscle displacement
systolic anterior motion seen with
⦁ increased contractility (ex: Digoxin, beta agonists, exercise)
⦁ decreased LV volume (ex: decreased venous return - standing, dehydration, Valsalva maneuver)
CAUSES OF HYPERTROPHIC CARDIOMYOPATHY
⦁ majority of primary cases = inherited - autosomal dominant mutation of single nucleotide (missense mutation)
Autosomal dominant mutations in β-myosin heavy chains are the most common cause of hypertrophic cardiomyopathy.
** mutation in the β-myosin heavy chain **
** or mutation in cardiac myosin binding protein-C **
Autosomal dominant = children of a parent with HCM have a 50% chance of also having HCM
FINDINGS OF HISTOLOGY = ** myocyte disarray ** - myofibers don’t line up properly
⦁ Another cause = Friedrich’s Ataxia - autosomal recessive neurodegenerative disease - often develop hypertrophic cardiomyopathy
Hypertrophic cardiomyopathy can be associated with Friedreich’s ataxia, an autosomal recessive inherited disease that causes progressive damage to the nervous system and manifests initially with gait disturbance, but does not affect cognitive function.
Secondary hypertrophic cardiomyopathy = can develop from essential HTN or aortic stenosis
Hypertrophic cardiomyopathy is a genetic and inherited form of heart disease. It causes enlargement of the heart wall, in particular, the septum, which leads to left ventricular outflow obstruction. Patients with hypertrophic cardiomyopathy can be characterized by syncope, shortness of breath, and chest pain
Exam = pulsus bisferiens = second pulse is felt
Cardiac examination will also show a loud, harsh, crescendo-decrescendo systolic murmur over the lower left sternal edge with radiation to the axilla. This murmur is accentuated by a Valsalva maneuver (forceful expiration against a closed airway)
DIAGNOSIS
⦁ ** echo **
- see asymmetrical wall thickness, especially septal thickness
- see systolic anterior motion of mitral valve leaflets
- see small LV size
- see dynamic outflow obstruction
- may see mitral regurgitation
⦁ EKG - LVH, increased QRS voltage, may also have atrial enlargement
⦁ CXR - cardiomegaly
TREATMENT
⦁ avoid dehydration + extreme exertion / exercise
⦁ *** BETA BLOCKERS = 1ST LINE * - helps slow down heart rate - allow enough time to completely fill and prevents arrhythmias from lack of oxygen to heart muscle
⦁ CCB (verapamil or diltiazem) if BB don’t work (non-dihydropyridines)
⦁ Disopyramide
β-blockers (metoprolol) and/or rate-limiting Ca channel blockers (usually verapamil) to decrease myocardial contractility and slow the heart rate and thus prolong diastolic filling and decrease outflow obstruction
- all 3 are negative inotropes = decrease force/speed of contractions + increase ventricular diastolic filling time
- do NOT give Digoxin (increases contractility)
- do NOT give Nitrates (decreases LV volume)
- do NOT give Diuretics (decreases LV volume)
Avoid nitrates and other drugs that decrease preload (eg, diuretics, ACEI, ARBs) because these decrease LV size and worsen LV function.
⦁ Surgery
- Myomectomy = resection of hypertrophied septum = usually done in patients with severe, refractory symptoms despite medical management
Beta blockers, calcium channel blockers, or cessation of high intensity athletics are all possible managements of hypertrophic cardiomyopathy.
⦁ Alcohol Septal Ablation = alternative to surgical management with good outcomes = “ a medical myomectomy” - use ethanol to destroy extra myocardial tissue
*** do NOT give Digoxin!!! - contraindicated because it can increase the contractility –> which can then increase the obstruction as blood is forced out of the ventricle
- ** ATHLETES ****
- *MURMUR = LOUDER WITH VALSALVA MANEUVER**
The murmur is accentuated when the patient stands up from a squatting position and with the valsava maneuver. The murmur decreases in intensity when the patient lays supine or squats
ACUTE MYOCARDIAL INFARCTION
- Cardiovascular Disease = leading cause of death worldwide, as well as in the US
- large proportion of CVD deaths = caused by heart attacks (AMI or MI)
PATHOPHYSIOLOGY
Infarction = tissue death due to lack of blood flow
MI = specifically heart muscle tissue
- death of heart muscle cells due to lack of blood flow (necrosis)
While the heart pumps blood to the rest of the body, the heart itself also requires blood to be oxygenated
- The heart pumps blood to itself via coronary circulation
AMI occurs when small coronary arteries get blocked and stop supplying blood / oxygen to heart tissue
- if the blockage occurs for long enough, a part of the heart tissue dies (necrosis)
Almost all heart attacks are a result of Endothelial Cell dysfunction - anything that inflames or irritates the inner lining of the artery (tunica intima)
CAUSES
⦁ tobacco toxins - float around in blood and damage endothelial cells
- this damage then becomes a site for atherosclerosis
⦁ severe atherosclerosis
⦁ hypotension
⦁ anything that leads to poor perfusion
Atherosclerosis = a type of coronary artery disease in which fat / cholesterol / proteins / calcium / WBCs build up and can block blood flow to the heart
A plaque has both a soft inner layer as well as a hard external fibrous cap - protects the plaque
- usually takes years for plaque to build up
- plaques partially block blood flow to the heart, but there is still some blood flow (not fully blocked off)
AMIs occur when there is a sudden complete blockage / occlusion of a coronary artery
- how does this happen?
1) plaques sitting in lumen of vessel are being stressed by mechanical forces of blood flow pushing past it
2) often it is the smaller plaques with less hard fibrous caps that are more prone to break or get ripped off from pressure of blood
3) inner filling of plaque (fat / cholesterol / protein / calcium / WBCs) is THROMBOGENIC = forms clots quickly!
4) platelets in blood adhere to exposed plaque material
5) platelets also release clotting signals to other platelets –> quickly clots
6) now artery is completely blocked off
3 COMMONLY BLOCKED CORONARY ARTERIES
1) LAD (left anterior descending artery)
⦁ descends down left anterior portion of the heart
⦁ supplies blood to the anterior wall / apex and anterior interventricular septum
⦁ accounts for 40-50% of cases of AMI
LCA (left coronary artery) –> branches off into LAD and Circumflex
2) RCA (right coronary artery)
⦁ supplies blood to RA, RV, posterior interventricular septum and posterior wall
⦁ accounts for 30-40% of cases
3) Circumflex Artery
⦁ supplies blood to LA and lateral wall of LV
⦁ accounts for about 15-20% of cases
- as these arteries more so involve the LV and left side of the heart, most heart attacks affect the LV
- right atrium / right ventricle not as often affected by AMI
HEART MUSCLE LAYERS
o Endocardium = smooth inner membrane
o Myocardium = heart muscle
o Epicardium = outer surface of heart = where the coronary arteries live
Initial Ischemia (insufficient blood flow) = muscle layer’s ability to contract is severely reduced
⦁ potentially reversible
⦁ after about 20-40 minutes, damage becomes irreversible, and cells start to die
- Zone of perfusion becomes zone of necrosis
- first area affected = inner 1/3 of myocardium - because it is the farthest area of myocardium from coronary artery, and is last to receive blood, and is subject to higher pressures from inside of heart
If blockage in artery suddenly breaks down / lyses, and blood flow returns, sometimes damage is then only limited to outer part of myocardium as blood flow is returned to remaining viable myocardium = SUBENDOCARDIAL INFARCTION
= NSTEMI or ST depression
STEMI or ST elevation = Transmural Infarction - where necrosis extends throughout entire myocardium after about 3-6 hours of complete blockage
NSTEMI vs STEMI
⦁ NSTEMI = ST depression, and only partial infarct of the wall
⦁ STEMI = ST elevation, and involve infarction of the whole wall thickness
SYMPTOMS OF AMI ⦁ severe / crushing chest pain or pressure ⦁ pain may radiate to left arm or jaw ⦁ diaphoresis (sweating) ⦁ dizziness ⦁ Nausea ⦁ fatigue ⦁ dyspnea or SOB
symptoms are all either a direct result of an organ, such as decreased perfusion to heart / brain / lungs / rest of body, or part of sympathetic response of body to help the heart work harder and preserve blood pressure (sweating)
- many people also have referred pain when the nerves in the heart get irritated –> pain can then be felt in jaw / shoulder / abdomen / back
DIAGNOSIS
⦁ EKG (ST elevation or depression)
⦁ Troponin I / T
⦁ CK-MB
- when heart muscles die, proteins / enzymes escape through damaged cell wall into the blood stream - elevated lab levels
Troponin I + T levels can be elevated in blood 2-4 hours after infarction, peak around 48 hours, can stay elevated for 7-10 days
CKMB elevates in blood after 2-4 hours, peaks at 24 hours, and returns back by 48 hours
CKMB can therefore be helpful in diagnosing reinfarction, since Troponin levels remain raised, as a 2nd heart attack occurs in about 10% of MI cases
COMPLICATIONS OF MIs
⦁ Arrhythmias - abnormal heart rhythms
- highest risk = immediately following MI, within 0-24 hours, as damage / injury can disrupt cell signaling
⦁ Cardiogenic Shock - 0-24 hours after MI, depending on how much heart muscle is damaged / necrosed, heart may not be able to pump as much blood to rest of body
⦁ Pericarditis - in 1-3 days following infarction, as the tissue around infarcted area becomes inflamed and invaded by neutrophils –> inflammation of pericardium
⦁ Myocardial Rupture - 3-14 days following infarction, macrophages invade - healing process begins with granulation tissue- tissue is at most risk for myocardial rupture
⦁ Heart Failure - after 2 weeks / months following infarction - remaining heart muscle works harder to make up for scarred / dead tissue - grows/changes shape to compensate for lost cells –> heart failure
TREATMENT
⦁ fibrinolytic therapy - break down clot
⦁ Antiplatelet medication - aspirin
⦁ Anticoagulants - heparin
⦁ Nitrates - relax (dilate) coronary arteries and help lower preload
⦁ Beta blockers - slow down HR - and therefore lower cardiac demand
⦁ Statin - maintain lipid levels
⦁ angioplasty - balloon used to open up artery
⦁ PCI - percutaneous coronary intervention - catheter used to place stent in coronary artery to physically open it up
- all to reestablish blood flow to dying heart cells
- if done early enough, may be able to prevent irreversible cell death
If damaged cells get reperfused (calcium) - causes cells to irreversibly contract –> causes “contraction bands” on pathology of reperfused damaged myocardium
DEEP VEIN THROMBOSIS (DVT)
Deep Veins = refers to the veins that typically runs between muscles as they travel back to the heart
(vs the superficial veins that you can see on surface of skin)
PATHOPHYSIOLOGY
⦁ DVT = deep vein thrombosis = blood clot in the deep veins that are responsible for bringing blood back to the heart
⦁ Superficial veins drain blood into deep veins, which rely on the skeletal muscle pump to move blood forward against gravity
⦁ The surrounding muscle compress the vein and propel blood forward
⦁ One-way valves prevent blood from going backwards
⦁ Deep veins ultimately lead to either SVC or IVC, and dumps blood into the right atrium
- ** MC LOCATION FOR DVT = LOWER LEGS ***
- MC = below the knee
- but blood clot can form in both superficial or deep veins, and in other parts of the body as well
** Most DVTs originate in the CALF **
DVT = MC in Left iliac vein than right iliac vein - because aortic bifurcation crosses and potentially compresses left iliac vein
1) Damage to the endothelium of blood vessel wall usually occurs
2) immediate vasoconstriction response –> limits the amount of blood flow
3) platelets adhere to the damaged vessel wall, and become activated by collagen + tissue factor (which are usually kept separate from blood due to intact endothelium, but now damaged
4) platelets recruit more platelets to create platelet plug = Primary Hemostasis
5) Coagulation Cascade is activated –> clotting factors made by the liver –> final step = fibrinogen getting activated into Fibrin ==> which forms a polymerized mesh around the platelets = Secondary Hemostasis
- results in a hard clot at the site of vessel injury
Only takes a few minutes from injury to clot formation
Usually anticoagulation proteins control coagulation cascade
⦁ Antithrombin = inactivates 9a, 10a, 11a, 12a, 7a, and thrombin
⦁ Protein C = inactivates 5a + 8a
6) As the clot grows in size, it decreased blood flow and decreases lumen size, which increases blood pressure
- the clot may start naturally breaking down due to increased pressure
** PLASMIN (enzyme) breaks down fibrin into fragments called D-DIMERS
7) Sometimes the pressure can cause a part of the main clot to break free = Embolus - can travel to the heart
Thromboembolism can move from leg –> IVC –> RA –> RV –> Lungs - can get lodged, causing a PE
= life threatening emergency, as it blocks blood from getting to the lungs to pick up oxygen
If ASD (atrial septal defect) = thromboembolism can go from RA to LA –> can go to the brain (Embolic Stroke)
In a patient with patent foramen ovale or ASD, DVT is a risk factor for a paradoxical embolism. A paradoxical embolism, also called a crossed embolism, is a kind of stroke or other form of arterial thrombosis caused by embolism of a thrombus (blood clot), air, tumor, fat, or amniotic fluid of venous origin through a lateral opening in the heart, such as a patent foramen ovale.
RISK FACTORS FOR DVT = ** VIRCHOW’S TRIAD **
⦁ 1) venous stasis (slowed blood flow)
- slow or static blood
- long periods of inactivity of skeletal muscle pump (bed rest / post-op, long flights/car rides, pregnancy - baby compresses nearby veins)
- in venous stasis, platelets and clotting factors have more time to contact the endothelium and adhere –> activation of clotting cascade
⦁ 2) Hypercoagulable state
- excess clotting factors - due to genetics, surgery, or taking certain medications like birth control, malignancy, factor V leiden, pregnancy
- during surgery, physical damage activates clotting cascade
- birth control increases clotting factors, and decreases anticoagulation factors like protein C + antithrombin
- just starting warfarin (before it acts as blood thinner)
⦁ 3) Damage to Endothelial lining of blood vessel
- this exposes tissue factor and collagen
- caused by infections, chronic inflammation (DM), toxins (like those in cigarettes), surgery, lower leg injury
VIRCHOW’S TRIAD (Risk factors for DVT)
1) Venous Stasis
2) Hypercoagulability
3) Damage to endothelial lining of blood vessels
SYMPTOMS OF DVT
⦁ MC in lower limbs, especially below the knee
⦁ pain
⦁ swelling
⦁ redness
⦁ warmth
⦁ Phlebitis = warmth, erythema, palpable cord
*** HOMAN’S SIGN = calf pain upon dorsiflexion of foot
MC symptom of DVT = leg swelling
If PULMONARY EMBOLISM OCCURS
⦁ shortness of breath / dyspnea
⦁ chest pain
⦁ hemoptysis
DVT = MC cause of PE
about half of patients with DVT are asymptomatic
** WELL’S CRITERIA ** = scoring system used to stratify the risk of having deep venous thrombosis
low risk (Wells’ Score <2) and a negative d-dimer the clinician can exclude the need for ultrasound (US) to rule out DVT
⦁ Active Cancer
⦁ Bedridden recently >3 days or major surgery in last 3 months
⦁ Calf swelling >3 cm compared to the other leg
⦁ Collateral (non-varicose) superficial veins present
⦁ Entire leg swollen
⦁ Localized tenderness along the deep venous system
⦁ pitting edema of symptomatic leg
⦁ Paralysis, paresis, or recent plaster immobilization of the lower extremity
⦁ previous documented DVT
⦁ Alternative diagnosis to DVT not as likely
** Unilateral swelling / edema of lower extremity > 3cm = most specific symptoms/sign of DVT **
- separate Well’s criteria for PE available
DIAGNOSIS OF DVT
⦁ ** Compression Ultrasound with doppler ** = test of choice = first line imaging
⦁ VENOGRAPHY if US inconclusive = GOLD STANDARD - dye injected into veins, XRAY to identify blockages
⦁ D-dimer can be helpful (fibrin breakdown products are usually higher in presence of a clot)
- normal d-dimer =/< 0.5
D-dimer should only be used as the first line test when the diagnosis seems unlikely
False positive D-dimer elevations = Pregnancy, Liver disease, Inflammation, Malignancy, Trauma, Hospitalized patients
TREATMENT
- main goal = preventing PE
- body will naturally try to break down clots on its own, so small clots may resolve on their own
- for larger clots
⦁ Anticoagulants: Heparin -> Warfarin
⦁ Thrombolytic enzymes
⦁ Thrombectomy (surgically remove clot)
In Unfractionated Heparin (IV) (Indication = prevents further emboli rather than treating existing one) - need to titrate to PTT 1.5-2.5x normal value
⦁ MOA = potentiates antithrombin III, inhibits thrombin / other coagulation factors
⦁ SE = HIT (heparin induced thrombocytopenia)
⦁ Antidote for Heparin toxicity = Protamine Sulfate
LMWH (Lovenox / Enoxaparin) SQ injection =
- don’t need to monitor PTT
- Safe in pregnancy
⦁ Lower risk of HIT**
⦁ Contraindication = thrombocytopenia, and renal failure if Creatinine > 2.0
⦁ Antidote for Heparin toxicity = Protamine Sulfate
- but not as effective as with UFH
Warfarin (Coumadin)
⦁ MOA = inhibits vitamin K-dependent coagulation factors of EXTRINSIC pathway: 2, 7, 9, 10. Inhibits protein C + S.
- Coumadin should be overlapped with heparin for at least 5 days AND until INR > 2-3 for at least 24 hours
⦁ Antidote for Warfarin toxicity = Vitamin K
⦁ Avoid cruciferous veggies with high levels of vitamin K (spinach, kale, brussel sprouts, greens) and green tea, cranberry juice, ETOH
Thrombolytics/thrombectomy = reserved for failed anticoagulation or massive thrombosis
LONG-TERM TREATMENT TO PREVENT FUTURE DVT
⦁ Anticoagulants (warfarin-coumadin / heparin / Lovenox / Eliquis / Xarelto)
⦁ Antiplatelets (low-dose ASA, Plavix)
⦁ Filters (can be placed in IVC to prevent PE)
IVC filter = reserved for patients with contraindications to anticoagulants, or those with little cardiopulmonary reserve in which an embolic event would kill them
ex: contraindications to anticoagulants + thrombolytics = intracranial hemorrhage or active bleeding, stroke or head trauma in last 3 months, BP > 185 / > 110, or known AV malformation
Heparin is an anticoagulant that is preferentially used to prevent and acutely manage DVT
Warfarin = oral vitamin K antagonist that is used for prophylaxis against DVT and has a teratogenic effect.
Ideally, DVT/PE should be confirmed before initiating anticoagulation therapy, but if the clinical suspicion is high or objective confirmatory studies are not forthcoming, anticoagulation therapy may be started, as patients can deteriorate rapidly and die
FIRST LINE TREATMENT FOR DVT = anticoagulation with IV heparin, then switch to warfarin x 3-6 months
Recurrent DVT requires lifetime anticoagulation
PREVENTION
⦁ compression stockings
⦁ calf exercises between long periods of stasis
⦁ ambulation as early as possible after embolization
women older than 35 years who smoke should avoid oral contraceptive pills due to risk of thrombosis. Progestin-Only Hormonal Methods are a reasonable alternative in this population.
Patient will present as → a 78-year-old female complaining of generalized pain and edema in her left leg. She denies chest pain, shortness of breath, and hemoptysis. She takes 2.5 mg warfarin daily for atrial fibrillation and her INR is 2.6. On physical examination the patient experience calf pain with dorsiflexion of the left foot. The patient has a positive D-dimer and a lower extremity ultrasound reveals the presence of a deep venous thrombosis in the left popliteal vein.
ABSOLUTE CONTRAINDICATIONS FOR ANTICOAGULATION THERAPY
⦁ recent brain bleed (in last 3 months)
⦁ active bleeding
⦁ thrombocytopenia below 50,000/mm3
⦁ recent or planned surgery
AORTIC ANEURYSM
- aneurysma = greek for “dilation”
ANEURYSM = abnormal dilations or bulge in vessel
officially termed aneurysm when the bulge or dilation is 1.5x larger than the normal diameter of the vessel
Aneurysms can occur to any artery in the body: Aorta, Femoral, Iliac, Popliteal, Cerebral, etc.
Aneurysms can occur in veins too, but the likelihood is much lower due to decreased pressure in veins
TRUE ANEURYSMS vs PSEUDOANEURYSMS
o True Aneurysm
- all layers of the blood vessel bulge out together
⦁ Fusiform = the dilation is symmetrical on all sides
⦁ Saccular or Berry = dilation is on one side - because for some reason that side had to put up with higher pressures, or is weaker than other side
o Pseudoaneurysm
⦁ not actually an aneurysm, but really a hole in the vessel wall that allows blood to leak out and look like an aneurysm
- looks like a perfect bulge due to surrounding structures / tissues that hold blood in that one spot - allowing it to look like a fusiform or berry aneurysm
MC Arterial Aneurysms = Aorta
⦁ 60% of aortic aneurysms = Abdominal aortic aneurysm *** (AAA or triple A)
⦁ other 40% of aortic aneurysms = thoracic section
- ** Majority of AAA = INFRARENAL *** - located just below where the renal arteries branch off, but above the aortic bifurcation into common iliac arteries
- this is because there is less elastin in this part of the aorta than others = weaker
PATHOPHYSIOLOGY OF ANEURYSMS
- weakness in vessel wall, so anything that causes the vessel walls to weaken can cause an aneurysm
- when a wall is weakened, it struggles to contain the pressure of blood pushing against it
- as the diameter of the weakened section dilates, the pressure on that part increases (Laplace’s Law), making the diameter of the aneurysm even bigger –> cycle of continuous bulging until rupture!
(this is why blowing up a balloon is tough at first, but gets easier as it stretches = due to positive feedback loop of increased diameter and increased pressure)
CAUSES OF ANEURYSMS / WEAKENED VESSEL WALL
⦁ ** MC CAUSE = SMOKING **
⦁ Hypertension
⦁ Hyperlipidemia / plaques
⦁ Mycotic aneurysms = caused by bacterial infections
⦁ genetic conditions - affect collagen / fibrillin (Marfans or Ehlers-Danlos)
o Hypertension
- vessels get blood supply as blood runs through them, but for thicker vessels, like descending aorta (thicker in order to handle high pressure from heart) = have own blood vessels in tunica media + tunica externa (tunica intima still gets supply from lumen blood) called VASA VASORUM
- Hypertension causes hyaline arteriosclerosis of vasa vasorum –> narrows lumen of vasa vasorum –> ischemia + atrophy of tunica media/externa smooth muscle –> weakens aorta wall –> aneurysm
o Plaques
- plaque buildup in tunica intima (atherosclerosis) –> that section of tunica intima doesn’t get oxygen –> ischemia (common in abdominal aorta - pressure is high, and vessel wall is nourished by flowing blood)
RISK FACTORS FOR ANEURYSMS (same as atherosclerosis) ⦁ male ⦁ > 60 ⦁ hypertension ⦁ family history ⦁ smoking ⦁ tertiary syphilis
Risk factors of abdominal aortic aneurysm include history of tobacco use, older age, male gender, and family history.
ENDARTERITIS OBLITERANS = inflammation of vasa vasorum (occurs with tertiary syphilis) -> fibrosis -> constricts the lumen of the vessels supplying oxygen to vessel wall - particularly of thoracic aorta (thicker vessels, so have vasa vasorum) –> atrophy
Thoracic aortic aneurysms are a common finding in tertiary syphilis.
MYCOTIC ANEURYSMS
- bacteria (or fungi) from an infection somewhere else in body can break off and travel elsewhere in the blood (embolic bacteria)
- usually gets stuck in intercranial arteries, visceral arteries or arteries feeding arms / legs
- bacteria weakens the vessels –> aneurysm
- commonly caused by
⦁ bacteroides fragilis
⦁ pseudomonas aeruginosa
⦁ salmonella
- Mycotic aneurysms = also a complication of infective endocarditis
- fungal causes
⦁ aspergillus
⦁ candida
⦁ mucor
MARFAN SYNDROME
- impaired elastic properties of fibrillin –> weak blood vessel walls
EHLERS - DANLOS SYNDROME
- disrupted ability to form collagen proteins
Thoracic aortic aneurysms are associated with connective tissue disease such as Marfans + ED
SIGNS / SYMPTOMS OF ANEURYSMS
- intact aneurysms = okay - usually don’t cause any symptoms
- but bulging vessel can compress nearby organs or vessels
- ex: bulge in aortic arch can compress SVC –> decrease amount of blood going to the heart
MOST CONCERNING COMPLICATION
- ** RUPTURE of aneurysm ***
- blood spills out of vessel, and less blood is getting to tissues / cells downstream that need it –> ischemia
- ** AORTIC INSUFFICIENCY ***
- particularly occurs when there is an aneurysm in thoracic aorta, right above aortic valve
- the dilation causes the aortic valve itself to expand and not close properly together, allowing blood to flow back into LV during diastole (Aortic regurgitation)
- Aortic insufficiency can also cause a high-pitched BRASSY COUGH due to aneurysm compressing on left recurrent laryngeal nerve that wraps around aorta
A bicuspid aortic valve is a known risk factor for thoracic aortic aneurysms.
BRAIN ANEURYSM
- if cerebral artery aneurysm ruptures = will bleed into SUBARACHNOID space –> puts pressure on brain tissue / irritates the meninges
⦁ sudden / intense HEADACHE
⦁ inability to flex neck forward
ANOTHER COMPLICATION OF ANEURYSMS
⦁ ** formation of BLOOD CLOTS **
- as blood is pooling into aneurysm prior to rupture, stasis of blood can form clots
- clot can become so big it blocks off entire artery –> ischemia…or
- part of clot can break off (thromboembolism) and travel elsewhere –> ischemia
ABDOMINAL AORTIC ANEURYSM SIGNS /SYMPTOMS
- sometimes asymptomatic, even if it has ruptured
⦁ severe flank pain / abdomen / chest / lower back / groin
⦁ pulsating mass that is in time with heartbeat
⦁ hypotension (in about 50%) - more indicative of rupture
Ruptured abdominal aortic aneurysm should be suspected in patients with abdominal pain radiating to the back and associated with hypotension (from retroperitoneal bleeding) and a pulsatile abdominal mass.
A presentation of hypotension, abdominal pain, and a pulsatile abdominal mass is characteristic of an abdominal aortic aneurysm which is in the process of rupturing.
AAA can be asymptomatic until further progression. AAA rupture is life-threatening and can present with abdominal pain, back pain, syncope, hypotension, tachycardia, pulsating abdominal mass, abdominal bruits, and severe pain.
THORACIC AORTIC ANEURYSM SIGNS / SYMPTOMS
- usually asymptomatic
⦁ severe chest / back / abdominal pain
⦁ respiratory difficulties
⦁ trouble swallowing
⦁ brassy cough / hoarseness (compression of left recurrent laryngeal nerve)
⦁ cardiac disease
⦁ rupture
⦁ may hear abdominal bruit as blood moves past aneurysm
Thoracic aortic aneurysm can lead to coughing and hoarseness due to compression of the left recurrent laryngeal nerve.
DIAGNOSIS OF ANEURYSMS
- because many are asymptomatic, they are often diagnosed incidentally
⦁ Ultrasound = initial study of choice
⦁ CT with contrast*** = test of choice
⦁ Angiography - Gadolinium = GOLD STANDARD
Acutely, AAA can be visualized and sized with an abdominal ultrasound.
CT and MRI are used to more accurately localize and determine size.
In the emergent setting, (actively rupturing) an abdominal ultrasound should be done because it is quick, noninvasive, sensitive, and has the ability to show free peritoneal fluid.
MC IV contrast = Iodine
Barium sulfate used for digestive system, Iodine = 2nd line if barium cannot be used
Possible adverse effects of iodinated contrast include warmth, contrast-induced neuropathy, and thyroid dysfunction
LABS / VITALS IF RUPTURED ⦁ hypotensive ⦁ tachycardic ⦁ leukocytosis (elevated WBC) - infection, malignancy, inflammation ⦁ anemia (decreased hematocrit)
Hematocrit = the ratio of the volume of red cells to the volume of whole blood. Normal range for hematocrit is different between the sexes and is approximately 45% to 52% for men and 37% to 48% for women.
TREATMENT
⦁ surgery
Treatment of non-rupturing AAA’s depends on aneurysm size:
⦁ < 5 cm diameter and asymptomatic - monitor with periodic ultrasound
- annual ultrasound if 3.0-4.0 cm
- q6m ultrasound if 4.0 - 4.5 cm
- q3m ultrasound if 4.5 - 5.4 cm + vascular surgeon referral
⦁ > 5.5 cm diameter or symptomatic or grew by 0.5 cm in 6 months - surgical repair using open or endovascular stenting.
⦁ BETA BLOCKER** = reduces shearing forces, decreases expansion and rupture risk.
Abdominal aortic aneurysm does not indicate surgery in asymptomatic patients until the aneurysm reaches a diameter of ≥5 cm.
In aneurysm cases of larger than 5 cm, EVAR
(Endovascular aneurysm repair) is more commonly used because it is less invasive than open aneurysm repair (catheter-based therapy).
⦁ Thoracic aortic aneurysms = surgery if 6cm+
Emergent surgery needed if aneurysm has ruptured or if symptomatic
the USPSTF recommends screening in any male 65-75 with a hx of smoking - 1 time screening via ultrasound
- screening also recommended in those with Marfans + Ehlers Danlos
ATRIAL FIBRILLATION
ATRIAL FIBRILLATION = IRREGULARLY IRREGULAR rhythm with narrow QRS, no P waves, just fibrillatory waves
A-fib = MC CHRONIC ARRHYTHMIA
- Most patients are asymptomatic
Fibrillation = when muscle fibers are contracting at different times –> quivering motion
Normally: SA node (in RA) sends signal that propagates out to both atria very rapidly, which allows the entirety of both atria to depolarize at around the same time –> nice coordinated contraction of atria
- the signal then moves down to AV node / ventricles to cause them to contract shortly after
WITH ATRIAL FIBRILLATION
- signals move around the atria in a disorganized way, which overrides the signal from the SA node
- instead of 1 big contraction, several mini contractions at different places of the atria –> looks like atria are just quivering or shaking
EKG
- p wave = atria contracting
- qrs wave = ventricles contracting
- in A-fib - will have squiggly lines where p wave should be
- occasionally a small atrial contraction will send a signal to the ventricles to contract, so QRS complexes are randomly interspersed between a-fib squiggles
NORMAL ATRIAL KICK
- when atria contract = sends last remainder of blood from atria into ventricles after passive filling occurs
- with A-fib = lack atrial kick - but not life threatening
CAUSE OF A-FIB
- not well known
- damage to atrial cells
- genetic component
RISK FACTORS FOR A-FIB
o Cardiovascular diseases
⦁ HTN, cardiac disease, ischemia, cardiomyopathies
⦁ coronary artery disease, infection, idiopathic
⦁ valvular disease
- essentially anything that could potentially stretch out atrial cells and damage those cells
- other risk factors = ⦁ obesity ⦁ DM ⦁ excessive alcohol consumption ⦁ Men > Women, White > Black
** MC Risk factor = HTN **
Think elderly + excessive alcohol use
- any of these risk factors could potentially cause damage to atrial cells, causing them to become very different from one another and therefore unpredictable
- if all atrial cells are essentially the same –> one-wave contraction occurs
- MULTIPLE WAVELET THEORY
multiple waves of signals are being conducted at different strengths / times / frequencies, and can run into each other, creating daughter wavelets - AUTOMATIC FOCUS THEORY
specific origin is thought to send out change in signal - thought to be where the pulmonary veins enter the atria - ** PAROXYSMAL ATRIAL FIBRILLATION ***
- people with a-fib usually start out with paroxysmal a-fib = where a-fib will suddenly comes and go
- lasts < 1 week, and is self-terminating
- usually lasts < 24 hours
PERSISTENT ATRIAL FIBRILLATION
- fails to self-terminate
- lasts > 1 week
- requires medical or electrical termination
For paroxysmal and persistent A-fib, with each episode = longer time that heart remains in a-fib / more often a-fib episodes will occur
PERMANENT ATRIAL FIBRILLATION
- persistent AF > 1 year
- is refractory to cardioversion, or cardioversion has never been tried before (if cardioversion worked = was not permanent A-fib)
LONE A-FIB
- paroxysmal, persistent or permanent A-fib without any evidence of heart disease (occurs in younger ppl)
sometimes the misfiring signals from a-fib can also make the ventricles beat too quickly. That’s a specific type of atrial fibrillation called AFib with rapid ventricular response (RVR) = if R-R intervals are irregular
SYMPTOMS OF A-FIB ⦁ may be asymptomatic ⦁ general fatigue ⦁ dizziness / syncope ⦁ SOB / dyspnea ⦁ weakness ⦁ may feel "palpitations"
general fatigue / weakness / SOB / dizziness = due to heart not being governed by SA node, and therefore not contracting regularly –> delivers blood / oxygen less effectively to tissues
COMPLICATIONS OF A-FIB
⦁ Stroke
- blood more stagnant in atria due not lack of full consistent contractions –> formation of clot
DIAGNOSIS
⦁ EKG - if persistent AF
- EKG: Heart rate is irregularly irregular
An absence of P waves - fibrillatory waves
Narrow QRS complex
Ventricular rate = usually 80-140
⦁ if paroxysmal = Holter monitor - a portable device that records rhythm during paroxysmal events
TREATMENT
o IF STABLE
1) RATE CONTROL = initial tx of symptomatic AF over rhythm control
⦁ Beta Blockers = 1st line (metoprolol, esmolol)
⦁ CCB (non-dihydro = Diltiazem, Verapamil)
⦁ Digoxin = preferred for rate control in patients with hypotension or CHF (not generally used in active pts)
- slows down HR to allow filling time between ventricular contractions to allow more blood to be send out with each contraction
Rate control strategy of managing atrial fibrillation aims to keep the heart rate < 110
2) RHYTHM CONTROL = may be used in younger patients with lone A-fib (no evidence of heart disease)
⦁ Synchronized Cardioversion (< 48 hrs)
- if AF present for < 48 hours = cardioversion
- if AF > 48 hrs = wait for 21 days after anticoagulation + after transesophageal echo (TEE) shows no atrial thrombi
⦁ Pharmacologic rhythm control
- Amiodarone
- Sotalol
- Flecainide
⦁ Radiofrequency Ablation followed by Permanent Pacemaker
o IF UNSTABLE = SYNCHRONIZED CARDIOVERSION
(tachyarrhythmia / hemodynamically unstable - BP)
o ANTICOAGULATION
- all patients with non-valvular A-fib = need
1) assessment of risk of embolization
⦁ CHADS2 or CHA2DS2-VASc score
2) determine benefits vs risks of anticoagulation
- does risk of embolization / stroke outweigh potential risk of bleeding out from anticoagulation
CHADS2 ⦁ CHF = 1 point ⦁ HTN = 1 point ⦁ Age ≥ 75 = 1 point ⦁ DM = 1 point ⦁ S2 = Stroke / TIA / Thrombus = 2 points Max = 6
≥ 2 = high risk => warfarin (maintain INR 2-3)
1 = moderate risk => warfarin or aspirin
0 = low risk => none or aspirin
CHA2-DS2-VAS ⦁ CHF = 1 point ⦁ HTN = 1 point ⦁ Age ≥ 75 = 2 points ⦁ DM = 1 point ⦁ S2 = Stroke / TIA / Thrombus = 2 points ⦁ Vascular dz (prior MI / PAD) = 1 point ⦁ Age 65-74 = 1 point ⦁ Sex (Female) = 1 point Max = 9
≥ 2 = moderate to high risk => chronic oral anticoagulation recommended
1 = low risk => discuss with patient
0 = low risk => none needed, but ask patient
ANTICOAGULATION MEDICATION
o Non-vitamin K antagonist oral anticoagulants (NOAC)
- usually now preferred over warfarin in most cases due to similar or lower rates of major bleeding + lower risk of ischemic stroke / don’t have to check INR, and less drug interactions
⦁ Dabigatran (Pradaxa) (direct thrombin inhibitor)
⦁ Rivaroxaban (Xarelto) (factor 10a inhibitor - binds to antithrombin III)
⦁ Apixaban (Eliquis)
o Warfarin - Indications = may be preferred in patients with ⦁ severe chronic kidney disease ⦁ CI to NOAC (HIV) ⦁ Mechanical heart valves ⦁ antiepileptic medications CP450 ⦁ cost issues (less expensive) ⦁ already on warfarin, don't want to change - Have to monitor INR (2-3 = goal) - monitor PT
o Dual Antiplatelet Therapy (Aspirin + Clopidogrel)
- anticoagulant monotherapy is preferred over dual antiplatelet therapy
- reserved for patients who cannot be on anticoags
PAROXYSMAL ATRIAL FIBRILLATION
atrial fibrillation suddenly comes and goes
- lasts < 1 week at a time (usually < 24 hours)
CAUSE
- probably because the tissue cells are still relatively healthy, have not become fully damaged yet
Repeated paroxysmal events tend to stress the atrial cells more, eventually leading to permanent a-fb
- thought to be due to CALCIUM OVERLOAD
- over time, atrial cells undergo progressive fibrosis, or scarring, and paroxysmal AF turns into PERSISTENT AF (lasts > 1 week without self-terminating)
- persistent AF can lasts weeks to months
PERSISTENT A-FIB
- fails to self terminate
- lasts > 1 week
- requires termination via medical or electrical tx
PERMANENT A-FIB
- persistent AF > 1 year
- refractory to cardioversion, or cardioversion has never been tried (if cardioversion worked = not permanent)
AORTIC DISSECTION
Aortic dissection = where part of the tunica intima (innermost layer of blood vessel) of the aorta, is RIPPED OFF
- a TEAR in the tunica intima forms, and the high pressure blood flowing through the aorta begins to tunnel between the tunica intima and tunica media, separating the two layers
- high pressure blood continues to tear through between the layers
- blood continues to pool, enlarging the vessel diameter
“FALSE LUMEN” = the area where blood collects
CAUSES OF AORTIC DISSECTION
In order for aortic dissection to occur, an underlying condition must be present that has weakened the aorta’s wall
⦁ chronic HTN = MC
- which is why it most often occurs in aorta
- from stress
- from increased blood volume (ex: pregnancy)
- from coarctation of artery (narrowing)
⦁ weakened aortic wall
- Ehler’s Danlos (CT disorder)
- Marfan’s (CT disorder) - fibrillin
- Loeys-Dietz syndrome (CT disorder - bifid uvula)
- decreased blood flow to vasa vasorum
⦁ aortic aneurysms —> can cause dissections
- dissections can also cause aneurysms
MC location for aortic dissection = first 10cm of aorta - closest to the heart
o Stanford Type A dissection = involves proximal aorta
- Aortic dissection commonly occurs in the proximal aorta, because this is the area of the aorta that is under the most stress.
o Stanford Type B dissection = involves distal aorta = is often less fatal compared to other types
COMPLICATIONS OF AORTIC DISSECTION
- depends on where the blood in the false lumen flows
⦁ blood could flow back up the aorta to the heart into pericardial space and cause
- PERICARDIAL TAMPONADE* = potentially fatal
- causes Equalization of the pressures within the heart
- When the pericardial fluid pressure exceeds that within ventricles, the ventricles are no longer able to fill appropriately, and the pressures within the four chambers of the heart equilibrate. This leads to decreased cardiac output and, ultimately, death if a prompt pericardiocentesis is not performed
- Signs of cardiac tamponade include a raised jugular venous pressure, hypotension, and pulsus paradoxus.
** PERCIARDIAL TAMPONADE = MC cause of death **
⦁ blood flowing through false lumen could burst through tunica media + externa - RUPTURE and could bleed into mediastinum - potentially fatal - rapid blood loss
⦁ blood flowing through false lumen could puncture back through tunica intima further down = not great, but could be worse
⦁ ** blood could continue to rip through tunica intima until it reaches another large artery that branches off the aorta, such as subclavian arteries or renal arteries
- false lumen could compress these arteries –> decreased blood flow to kidneys / arms / wherever
SYMPTOMS
⦁ sharp TEARING chest pain -> often radiates to back
⦁ weak / decreased peripheral pulses (such as radial, carotid, brachial or femoral arteries)
⦁ * may have differences in blood pressure between right and left arm *
⦁ hypertension (MC) or hypotension
⦁ tachycardia
⦁ lightheaded / dizzy
⦁ N / V
⦁ diaphoresis
⦁ can lead to shock if significant blood loss from rupture
- may have aortic regurgitation (diastolic crescendo-decrescendo murmur), acute MI, or cardiac tamponade
o anterior chest pain = more ascending aorta (A)
o aortic arch –> neck / jaw pain
o interscapular pain = more descending aorta (B)
Measuring blood pressure in both arms is a quick clinical method to detect thoracic aortic dissection.
AORTIC DISSECTION IS AN EMERGENCY
An aortic dissection is considered a medical emergency due to the high risk of life-threatening complications such as cardiac tamponade, aortic regurgitation, and myocardial infarction.
A hypertensive emergency may be characterized by organ damage, such as an aortic dissection.
DIAGNOSIS
⦁ CT with contrast = rapidly becoming test of choice, especially in the ER
⦁ Angiography = gold standard / definitive
** CT Angiography ** = looks closely at blood vessels
⦁ TEE (transesophageal echo) - ultrasound probe goes through esophagus to get clear view of aorta
= best initial test if hemodynamically unstable
⦁ CXR - widened aorta or widened mediastinum
CT or MRI with angiography = gold standard for diagnosing an aortic dissection
If patient cannot be injected with dye due to impaired renal function or allergy = MRI*
= would be done after patient has been stabilized
MRI has very high specificity and sensitivity for the detection of aortic dissection and is commonly used as a gold standard for diagnosing the condition in the patient who cannot tolerate IV contrast because of renal insufficiency
TREATMENT
⦁ Stanford Type A dissection (Debakey I + II) = SURGERY
- removal of as much of dissected aorta as possible, then block re–entry of blood into aorta wall
- wall is reconstructed with synthetic graft
- sometimes a stent is placed to prop open graft
ALL ascending aortic dissections should be managed with surgery; however, surgery is only indicated for descending dissections when there is evidence of end-organ damage.
⦁ BP medication
- Beta blockers*** - Esmolol, Labetalol, Propranolol
- Stanford type B dissection (Debakey III) = FIRST TREATED WITH BETA BLOCKERS, then vasodilators
- then give nitro if needed
- can use CCB (Nicardipine) if can’t take BB
If the hypertension is refractory to the β-blocker, nitroprusside may be used to further lower systolic blood pressure. CCB like verapamil are used if the patient cannot tolerate β-blocker
AV MALFORMATION (ARTERIOVENOUS MALFORMATION) or AVM
AVM = bad or abnormal formation between arteries and veins
Normal Physiology
- arteries carry oxygenated blood to tissues
- arteries branch into arterioles which branch into capillary beds where O2 and CO2 are exchanged
- veins then carry oxygen-rich blood back to heart
The pressure in arteries is HIGH
- the pressure decreases as blood moves from arteries to capillaries, and even lower pressure in veins
- capillaries dampen the arterial flow a bit to prevent high pressures in the veins (not equipped to handle high pressures)
AVM
⦁ entire capillary bed (and arterioles) = MISSING
⦁ the group of arteries directly links up to the group of veins
⦁ the vessels in AVM can start to tangle and form a NIDUS (“nest”)
AV FISTULA = when artery vessel –> vein
- when a single artery branches directly into single vein
in AVM, the arteries and the veins are therefore in HIGH SYSTOLIC BLOOD PRESSURE, because there are no capillaries to dampen the pressure
- the AVM Nidus can then expand in size and put pressure on surrounding tissue and surrounding capillaries –> prevent other tissues from getting enough blood flow (ischemia)
- the high pressure causes vessels to dilate
- causes veins to THICKEN –> FIBROSIS
Vessel walls are weakened and stretched out from high pressures –> can eventually lead to ANEURYSM or RUPTURE
- can be a small bleed –> forms a clot
- may not have any symptoms, but would still ideally want to treat that AVM as it is at risk for rupture again, and potentially with a much more severe bleed
CAUSE OF AVMs
- not well understood
- thought to be congenital - some sort of vessel growth dysfunction during embryonic or fetal development
- may be genetic
RISK FACTORS
- Males
- Family hx of AVM
- ** OSLER - WEBER - RENDU disease ** = Also known as Hereditary hemorrhagic telangiectasia syndrome = autosomal dominant disorder - causes blood vessel disorder all over the body
LOCATION
- AVMs can form anywhere in the body
⦁ MC location = ** brain + spinal cord + lungs **
The posterior branches of the MIDDLE CEREBRAL ARTERY are the most common arteries affected by the arteriovenous malformations.
at risk for RUPTURE
- drug use can cause AVMs to rupture
In >50% of patients with AVM, hemorrhage is the first symptom.
Symptoms due to bleeding include loss of consciousness, sudden and severe headache, nausea, vomiting, incontinence, and blurred vision, amongst others.
Drug use is a risk factor for AVM rupture (and this is hinted at in the question “there is redness around the nares bilaterally.”
Impairments caused by local brain tissue damage on the bleed site are also possible, including seizure, one-sided weakness (hemiparesis), a loss of touch sensation on one side of the body and deficits in language processing (aphasia).
Minor bleeding can occur with no noticeable symptoms. Following the bleed’s cessation, most AVM victims return to normal, after the blood vessel has had time to repair itself. In this patient, however, there is evidence of brainstem herniation (fixed, dilated pupil) so the prognosis is very poor.
SYMPTOMS
o ** BRUIT ** as blood rushes through AVM
- person can often hear it themselves if AVM is in brain
o If AVM ruptures in brain, can either be a microbleed, but if severe blood loss = SAH
- AVMs in brain are usually single
- SUBARACHNOID HEMORRHAGE –> can cause neurological symptoms
⦁ headache
⦁ seizure
⦁ if affects hippocampus –> can affect memory
⦁ if affects basal ganglia –> can affect movement
Brain AVMs usually present between the ages of 10 and 40 years.
In about half of all brain AVMs, intracranial HEMORRHAGE is the FIRST SIGN
Brain AVMs underlie 1 to 2 percent of all strokes, 3 percent of strokes in young adults, and 9 percent of subarachnoid hemorrhages
o If AVM ruptures in spinal cord = can damage nerve fibers
⦁ sensory disturbances
⦁ muscle weakness
⦁ paralysis in parts of body controlled by those nerves
o if AVM ruptures in lungs = can lead to
⦁ SOB
⦁ hemoptysis
WASTED WORK to have blood flow from heart –> AVM –> back to heart
- oxygen is NOT going to tissues capillaries, and blood is just rerouting back to the heart
- over time, heart has to work harder –> HEART FAILURE
DIAGNOSIS
⦁ ** ANGIOGRAPHY ** = gold standard
⦁ CT
⦁ MRI
- MC SIGN OF BRAIN AVM = BRAIN HEMORRHAGE **
- others = headache, epilepsy, neurologic symptoms
Spetzler-Martin grading system is used for preoperative risk-stratification of brain arteriovenous malformations
TREATMENT
⦁ most AVMs are treated regardless of if symptomatic or not - due to potential for complications
= SURGICAL EXCISION
o Radiosurgery = 1st alternative for non-surgical candidates = laser AVM to close off malformation
o Endovascular Embolization = adjunct - catheter used to obstruct the vessels in AVM
- Radiotherapy = used in patients who are not surgical candidates
⦁ symptomatic treatment for headaches / seizures
Patient will present as → a 63-year-old illiterate female with a history of right motor partial seizures and generalization since the age of 23 years arrives at the emergency room due to acute right hemiparesis. Neurological examination reveals a right hemiparesis, right tactile and pain hypoesthesia, poor fluency, temporal and spatial disorientation, and a Mini-Mental State Examination score of 5 points (one for immediate memory, two for naming, one for repetition, and one for commands).
BLUE RUBBER BLEB SYNDROME
Blue rubber bleb nevus syndrome is a rare, autosomal dominant or sporadic condition that consists of blue-black, rubbery blebs under the skin and internal vascular malformations, most frequently of the gastrointestinal tract
⦁ blue-black/purple, rubbery “blebs” under the skin - MC on chest and arms
- compressible, rubber-like lesions under the skin
⦁ AVMs most frequently in the GI tract - small bowel
The skin blebs typically present at birth or early childhood and may increase or multiply with age
Gastrointestinal involvement typically presents itself in early adulthood.
Other organs that can reportedly be affected by blue rubber bleb nevus syndrome include the CNS, lungs, kidneys, liver, musculoskeletal system and others.
Gastrointestinal bleeding in adulthood may present overtly with melena, blood per rectum or bloody vomitus, or more insidiously with iron-deficiency anemia and chronic fatigue.
There is no “standard of care” for blue rubber bleb nevus syndrome. However, physicians are recommended to schedule regular checkups to assess for ANEMIA and rule out GI BLEEDS
Occasionally, sudden gastrointestinal hemorrhage can lead to death. Central nervous system involvement may also lead to fatal intracranial hemorrhage.
It is important to refer patients with these characteristic skin blebs to a gastroenterologist and to other specialty practitioners depending on the organs involved.
AORTIC STENOSIS
**MC VALVULAR DISEASE*****
PATHOPHYSIOLOGY
- outflow obstruction of blood from the left ventricle to the aorta. Due to stenosis, the left ventricular pressure must rise greater than aortic pressure in order to force blood through. This results in left ventricular hypertrophy, as the left ventricle requires more sarcomeres to have a greater contraction and to sustain high pressure. This normalizes wall stress, leading to thickness + Left diastolic dilatation
- This eventually leads to Left Atrial hypertrophy and enlargement in order to have enough pressure to fill the left ventricle.
- Severe stenosis limits the ability to increase stroke volume on demand (amount of blood being pumped out of the left ventricle per beat)
- Concentric Hypertrophy - hypertrophy is in the same amount in all areas of the left ventricle, and maintains the relative shape of the left ventricle. Concentric hypertrophy reduces wall stress but also reduces ventricular compliance. Left ventricular end diastolic pressure increases (pressure at rest), and therefore the left atrial pressure has to increase (hypertrophy/enlargement)
Aortic Stenosis ==> LVH ==> LAE
ETIOLOGY
⦁ Calcified Aortic Stenosis (heart disease)
⦁ Congenital Bicuspid Aortic Valve (MC in young pts)
⦁ Rheumatic Fever Aortic Valve Disease
WHAT CAUSES AORTIC STENOSIS?
⦁ 1) Degenerative Heart Disease = Calcifications. Mechanical stress over time causes damage to the endothelial cells around the aortic valve, causing calcification and fibrosis of the valve, which hardens the valve and makes it more difficult to open up completely. This is usually seen in the elderly/late adulthood (>60)
⦁ Having a bicuspid aortic valve rather than a tricuspid aortic valve - the mechanical stress that is usually divided among 3 leaflets is not being split over 2 leaflets = more stress per leaflet -> earlier fibrosis/calcification of the valve
⦁ Chronic Rheumatic Fever - repeated inflammation followed by repair, which leads to fibrosis. The leaflets can actually fuse together, called Commissural Fusion
CARDINAL SYMPTOMS OF SEVERE AORTIC STENOSIS
⦁ Syncope - decreased oxygenated blood to brain
⦁ Angina - decreased oxygenated blood to heart
⦁ Dyspnea - due to left ventricular hypertrophy / blood backing up into lungs = 1ST SYMPTOM
Aortic Stenosis Complications o Angina o Syncope o CHF = worst prognosis o Dyspnea + Pulmonary edema
- Long asymptomatic “latent” period of aortic stenosis, as stenosis can take years to show symptoms.
Sudden death = most common cause of acute demise from aortic stenosis.
Left ventricular dilatation + hypertrophy –> contractile failure due to over-induced ejection fraction
- prone to develop endocarditis due to tendency of organisms to adhere to endocardium. will eventually cause vegetations of the valve, which can embolize to different parts of the body
- Can develop arrhythmias: Ventricular tachycardia (speeds up contractions to get more blood to the body, but this prevents heart from getting enough blood), Conduction System disease, and Atrial Fibrillation
PATHOPHYSIOLOGY FOR SHORTNESS OF BREATH IN AORTIC STENOSIS
- LVH –> leads to diastolic dysfunction (pressure is too high in the left ventricle, makes filling difficult)
- LV dilatation + contractile failure
- systolic dysfunction
- Increased left ventricular end diastolic pressure –> increased left atrial pressure –> increased pulmonary capillary pressure –> decreased pulmonary compliance (ability to stretch) –> SOB
PATHOPHYSIOLOGY FOR ANGINA IN AORTIC STENOSIS
- Increased wall stress leads to increased myocardial oxygen demands, and these oxygen demands exceed the coronary ability to meet the oxygen flow demands
- LV hypertrophy –> decreased filling volume –> decreased stroke volume
- decreased stroke volume –> tachycardia / arrhythmias –> can prevent enough blood from getting to coronary arteries
PATHOPHYSIOLOGY FOR SYNCOPE IN AORTIC STENOSIS
- Fixed cardiac output: decreased cardiac output amount leads to drop in cerebral perfusion pressure.
SYMPTOMS / CLINICAL FINDINGS
⦁ ** SYSTOLIC EJECTION CLICK **
⦁ ** CRESCENDO / DECRESCENDO MURMUR **
⦁ MURMUR RADIATES TO THE CAROTID + APEX
⦁ PULSUS PARVUS ET TARDUS (weak, delayed carotid pulse)
⦁ NARROWED PULSE PRESSURE (small difference between systolic + diastolic pressure)
- unlike aortic regurgitation = widened pulse pressure
⦁ Heart - Systolic Ejection Murmur - best heard at 2nd Right ICS / Right upper sternal border
⦁ Lungs - Rales (crackles) - sign of failure
⦁ Extremities - cold + decreased pulses
Signs of severe AS include:
⦁ late-peaking murmur
⦁ paradoxically split S2**
⦁ small and delayed carotid pulses (pulsus parvus et tardes)
⦁ a LV heave
⦁ an audible (and occasionally palpable) S4**
Prolonged ejection time
NARROWED PULSE PRESSURE
- systolic BP = decreases
- diastolic BP = same
INCREASED MURMUR
- squatting (increases preload)
- leg raise (increases preload)
- sitting + leaning forward (increases preload)
- expiration
- increased blood in LV –> increased murmur
DECREASED MURMUR
- Valsalva (decreases preload)
- standing (decreases preload)
- handgrip (increases afterload)
- inspiration
- decreased preload = decreased blood in LV –> decreased murmur
- increased afterload = more pressure in LV
maneuvers like Valsalva + standing = decrease venous return (decrease preload) ==> decrease murmur intensity
squatting = increase venous return (increase preload) ==> increase murmur intensity
handgrip = increases afterload = decreases murmur intensity
o decreased blood flow to the brain –> Syncope.
o decreased blood flow to coronary arteries –> Angina (chest pain). Symptoms may not be experienced during rest, only during exertion/exercise, because the body needs more blood during exercise.
o blood backed up into lungs / pulmonary congestion (dyspnea)
COMMON TRIAD = Syncope + Angina + Dyspnea (SAD)
S - Syncope
A - Angina
D - Dyspnea
- Parvis et Tardis = small volume (parvis) + slow rising (tardis) pulses = weak + slow pulses
- When the valve is hardened/fused, making it more difficult to open, the pressure on the valve increases when the left ventricle contracts, causing it to snap open ==> “EJECTION CLICK.”
- murmur sound due to increased turbulence as blood is moving through a narrowed valve. The murmur gets initially louder as more blood flows through the valve, and then gets softer as less blood is being pushed from the left ventricle to the aorta = Called a CRESCENDO / DECRESCENDO murmur, in which the murmur is heard between S1 (AV valves close) and S2 (SL valves close). The murmur gets louder then softer.
Systolic Ejection murmur
- due to the hardened/narrowed aortic valve, the left ventricle must generate high pressures in order to push the blood through to the aorta => Left Ventricular Hypertrophy - left ventricular muscle thickens. Even with hypertrophy, still hard to pump blood through the valve, so vital organs may not be receiving enough oxygenated blood, including the heart itself -> can lead to heart failure.
A complication of aortic stenosis is experiencing a SYNCOPAL EPISODE DURING EXERCISE due to limited ability of blood flow across stenosed valve.
Calcific aortic stenosis is a heart valve pathology that is common in people >60.
** May have HEMOLYTIC ANEMIA: damage to RBCs as they are forced through the narrow valve –> Schistocytes (helmet cells), which leads to hemoglobinuria (hemoglobin in the urine) **
DIAGNOSIS OF AORTIC STENOSIS
⦁ Echo - aortic valve thickening + restricted motion
⦁ EKG - see LVH with “strain pattern”. may also see LAE, LBBB
- Left bundle branch block is associated with aortic stenosis.
⦁ CXR - aortic root dilation, pulmonary congestion
⦁ Doppler - Increased flow velocity across aortic valve
⦁ Cardiac Cath = DEFINITIVE DIAGNOSIS = can calculate valve area by measuring gradient across aortic valve (< 1 cm = critical aortic stenosis) - can also look at coronaries. Useful in symptomatic patients prior to surgery
Normal aortic valve area = 3-4cm. Aortic Stenosis = 0.75-1.0 cm wide - is affecting circulation
⦁ Mild AS = > 1.5 cm [gradient < 25 mmHg]
⦁ Moderate AS = 1.0-1.5 cm [gradient 25-50 mmHg]
⦁ Severe AS = < 1.0 cm [gradient >50 mmHg]
TREATMENT OF AORTIC STENOSIS
**AORTIC VALVE REPLACEMENT = only effective treatment of choice ***
- if symptomatic = valve replacement, or if asymptomatic and valve area < 0.6 cm
⦁ Mild to moderate asymptomatic aortic stenosis = do close follow-ups, history + physical exam, serial echocardiograms, and endocarditis prophylaxis
⦁ Severe - symptomatic aortic stenosis (1 year survival rate of 57%) =
- aortic valve replacement with either mechanical or bioprosthetic valve. With valve replacement, 10 year survival = 75%).
- mechanical = longer durability but thrombogenic - must be on anticoagulant therapy long-term
- bioprosthetic = less durable, but minimally thrombogenic - usually used in patients who cannot be on anticoagulants
Other options
1) Percutaneous Aortic Valvuloplasty = balloon widening; 50% successful, but 50% restenose in 6-12 months = bridge to AVR (aortic valve replacement) if not a surgical candidate or in pediatric patients
2) Intraortic balloon pump = temporary stabilization as a bridge to valve replacement
MEDICATIONS - no medical treatment is truly effective, but if severe aortic stenosis = avoid exertion, and avoid BB / CCB (negative inotropes) and avoid venodilators (nitrates)
Patient will present as → a 59-year-old male with chest pain, dyspnea, and presyncope. The symptoms occurred after climbing a flight of stairs. He has a late systolic-ejection murmur (SEM) heard in the second intercostal space (ICS) at the right sternal border with radiation to the carotids and the apex. The murmur is decreased with Valsalva maneuver. EKG is suggestive of LV hypertrophy.
EKG LEFT VENTRICULAR HYPERTROPHY (LVH)
Left ventricular hypertrophy can occur after many years of poorly controlled hypertension.
ECG will show
⦁ increased R-wave amplitude in the left-sided ECG leads (I, aVL, V4-V6)
⦁ increased S-wave depth in the right-sided leads (III, aVR, V1-V3).
A common criteria is the Sokolov-Lyon criteria (S-wave depth in V1 + tallest R-wave height in V5-V6 >35 mm).
In LVH, you may also see other characteristic patterns on the ECG, including left atrial enlargement, left axis deviation, and an “LV strain” pattern. An LV strain pattern is T-wave inversion in the lateral leads (I, aVL, V5-V6).
EKG LEFT BUNDLE BRANCH BLOCK (LBBB)
Left bundle branch block is associated with aortic stenosis.
The ECG criteria for LBBB are:
⦁ a widened QRS-interval, >120 ms
⦁ broad monomorphic R-waves in I and V6 with no Q-waves
⦁ broad monomorphic S-waves in V1
*** LBBB = R waves in I + V5 / V6
broad S waves in V1 / V2
EKG RIGHT BUNDLE BRANCH BLOCK (RBBB)
In a right bundle branch block, the depolarization of the right ventricle is delayed.
This means there will be a
⦁ positive QRS-complex (R-wave) in lead V1
⦁ negative QRS-complex (S-wave) in lead V6
*** RBBB = R waves in V1 / V2
S waves in I / V5 / V6
NITROGLYCERIN
Nitroglycerin can cause
⦁ reflex tachycardia
⦁ flushing
⦁ headache
MOA = It produces a vasodilator effect on the peripheral veins and arteries with more prominent effects on the veins.
Nitroglycerine primarily reduces cardiac oxygen demand by DECREASING PRELOAD as well as some reduction in afterload.
It dilates coronary arteries and improves collateral flow to ischemic regions.
Nitroglycerine vasodilates blood vessels by releasing nitric oxide in smooth muscle. This vasodilation can cause hypotension.
The elevated heart rate is reflexive in nature; the heart attempts to compensate for the drop in blood pressure.
AORTIC REGURGITATION = AORTIC INSUFFICIENCY
Aortic Valve = 3 leaflets
- left / right / posterior leaflets
⦁ Opens during systole to allow blood to be ejected to body
⦁ Closes during diastole to allow heart to fill with blood to get ready for another systole
If aortic valve doesn’t open all the way = aortic stenosis
if aortic valve doesn’t close all the way = aortic regurgitation
AORTIC REGURGITATION = aortic valve doesn’t fully close after systole, so during diastole, some blood falls back into the LV, joining the blood coming into the LV from the LA
normal aortic valve opens up to 3-4cm
CAUSES OF AORTIC REGURGITATION
⦁ MC = ** aortic root dilation ** (50%)
⦁ Valvular damage (endocarditis or chronic rheumatic fever)
AORTIC ROOT DILATION
- widening of aortic roots, which pulls apart the leaflets to where they don’t close together anymore
- majority of aortic root dilations = idiopathic* (unknown)- other causes of aortic root dilation = aneurysms, aortic dissections, syphilis, Marfans / Ehlers Danlos, RA, SLE, hypertension - can all lead to widened aortic root
VALVULAR DAMAGE
- chronic inflammation –> fibrosis –> prevents valve leaflets from coming together to firm tight seal
SYMPTOMS
⦁ EARLY / BLOWING / SOFT / HIGH-PITCHED DESCRESCENDO DIASTOLIC MURMUR
- best heard along LSB (left sternal border)
- diastolic murmur
- decrescendo as blood is leaking back into LV
- occurs AFTER S2 (closing of AV valves), before S1
⦁ ** WIDENED PULSE PRESSURE **
(unlike aortic stenosis = narrowed pulse pressure)
- LV blood volume increases –> increased LV stroke volume –> increased systolic BP
- but less blood volume in the aorta during diastole –> decreased diastolic BP
⦁ ** BOUNDING PULSES **
- hyperdynamic circulation due to widened pulse pressure
- –> HEAD BOBBING with heartbeat (De Musset sign)
- –> QUINCKE’S PULSES - pulsating capillary beds in fingernails
- –> PULSATING UVULA (Muller’s sign)
- –> Corrigan’s Pulse = bounding pulse in carotid artery
** PULSUS BISFERIENS ** = seen with severe AR as well as with HOCM = double pulsed carotid upstroke
⦁ Eccentric LEFT VENTRICULAR HYPERTROPHY
due to increase in blood volume from both regurgitation and left atrium
⦁ ** AUSTIN FLINT MURMUR ** = mid-late diastolic rumble at the apex secondary to retrograde regurgitant flow competing with antegrade flow from left atrium into LV
SYMPTOMS
⦁ Early blowing decrescendo diastolic murmur
⦁ Widened pulse pressure
⦁ Bounding pulses / head bobbing / quincke’s pulse
⦁ LVH
INCREASED MURMUR
- squatting (increases preload)
- sitting + leaning forward
- handgrip (increases afterload –> more regurgitation)
- expiration
- ** handgrip = decreases aortic stenosis murmur, increases aortic regurgitation murmur
- everything else = same
DECREASED MURMUR
- Valsalva
- standing
- inspiration
DIAGNOSIS
⦁ ** ECHO **
TREATMENT
⦁ ** AORTIC VALVE REPLACEMENT ** = definitive
- if symptomatic or if left ventricular dysfunction develops (EF < 55%)
- even though 55% EF is normal, patients with Aortic regurgitation need a hyperdynamic ventricle in order to maintain adequate cardiac output
⦁ mainstay of tx = decrease afterload
- vasodilators: ACEI / ARBs / Nifedipine / Hydralazine
- afterload reduction improves ventricular performance by increasing forward flow
don’t want to decrease preload = even less blood will get out to the body with regurgitation
CIRCULATORY SHOCK
Shock = inadequate organ perfusion + tissue oxygenation to meet the body’s oxygenation requirements
**often associated with Hypotension (but not always)
Shock = determined by either
1) low cardiac output
2) low systemic vascular resistance (SVR)
SVR = the resistance to blood flow through the circulatory system
- peripheral vasoconstriction increases SVR
- vasodilation decreases SVR
4 main types of shock ⦁ Hypovolemic ⦁ Cardiogenic ⦁ Obstructive ⦁ Distributive
HYPOVOLEMIC = loss of blood/ fluid volume –> shock
ex: hemorrhage
CARDIOGENIC = myocardial dysfunction leads to reduced cardiac output –> shock
ex: MI
OBSTRUCTIVE = obstruction to circulation –> shock
ex: cardiac tamponade
DISTRIBUTIVE = maldistribution of blood flow from essential organs to nonessential organs
ex: septic shock
ex: anaphylactic shock
ex: neurogenic shock
PATHOPHYSIOLOGY OF SHOCK
1) Inadequate tissue perfusion
- inability to meet the body’s metabolic oxygen requirements –> anaerobic respiration –> lactic acid production –> metabolic acidosis + organ dysfunction
2) Nervous system activation
- in an attempt to improve systemic oxygen delivery
⦁ Vasoconstriction (to increase SVR)
⦁ Tachycardia (to increase cardiac output)
⦁ increased NE / Dopamine / Cortisol release
⦁ RAAS activation to increase volume (+ vasoconstriction)
3) Systemic Effects of Shock
⦁ Metabolic Acidosis
- lack of oxygen, so cells turn to anaerobic metabolism –> produces lactic acid byproduct
⦁ MODS = Multiorgan Dysfunction Syndrome
- consequences of shock on organ systems - includes lungs / kidneys / heart / brain dysfunction, as well as DIC
⦁ MSOF = Multisystem Organ Failure - if condition persists
GENERAL SYMPTOMS OF SHOCK ⦁ acutely ill ⦁ altered mental status ⦁ decreased pulses ⦁ tachycardia ⦁ cool / mottled / clammy skin ⦁ warm / flushed skin if distributive shock ⦁ hypotension: Systolic BP < 110 - may be normotensive initially
DIAGNOSTIC TESTS ⦁ CBC ⦁ CMP ⦁ Lactate ⦁ Coag studies ⦁ Cultures ⦁ ABG - others depending on etiology
GENERAL MANAGEMENT OF SHOCK
⦁ Airway (may need intubation)
⦁ Breathing (mechanical ventilation + sedation decreases the work of breathing, reducing the oxygen demand associated with tachypnea)
⦁ Circulation: isotonic crystalloids (NS / LR)
⦁ Oxygen (monitor lactate levels)
⦁ Endpoint of resuscitation = urine output, CVP, MAP
HYPOVOLEMIC SHOCK
- shock = decreased blood flow to the whole body
- circulatory failure –> cellular damage and possibly multi-organ failure if not treated immediately
Shock is like ischemia (decreased blood flow to tissue), but on a global scale
Shock = body’s tissues aren’t getting enough blood, and therefore aren’t getting enough oxygen
Blood is delivered to tissues because of blood pressure - enough pressure circulating blood throughout the body
Blood pressure = resistance to flow x cardiac output 1) resistance to flow - determined by ⦁ vessel length ⦁ blood viscosity ⦁ vessel diameter
2) cardiac output (amount of blood pumped by the heart out to the body per minute)
⦁ cardiac output = HR (bpm) X SV (volume per beat)
⦁ stroke volume = EDV (amt of blood in LV after diastole) - ESV (amount of blood left over in LV after contraction or systole)
HYPOVOLEMIC SHOCK
- low blood volume that leads to shock
- can either be non-hemorrhagic or hemorrhagic
Loss of blood or fluid volume due to hemorrhage or fluid loss that leads to shock
Hypovolemic shock divided into Hemorrhagic and Non-hemorrhagic.
1) HEMORRHAGIC HYPOVOLEMIC SHOCK
- loss of blood volume from bleeding
- loss of about 20% of blood volume (about 1L) = could be enough to cause hypovolemic shock
⦁ GI bleed
⦁ AAA rupture
⦁ massive hemoptysis
⦁ trauma
⦁ ectopic pregnancy
⦁ postpartum hemorrhage
etc.
NON-HEMORRHAGIC HYPOVOLEMIC SHOCK - loss of fluid volume is NOT from bleeding ⦁ severe dehydration ⦁ severe vomiting ⦁ bowel obstruction ⦁ pancreatitis ⦁ severe burns ⦁ DKA (osmotic diuresis due to hyperglycemia)
PATHOPHYSIOLOGY
1) lack of blood volume –> decreased EDV
2) decreased EDV –> decreased SV
3) decreased SV –> decreased CO
4) decreased CO –> decreased BP
Loss of blood or fluid volume –> increased heart rate, vasoconstriction (increased SVR), hypotension, and decreased CO
The body’s response to hypovolemia = peripheral vasoconstriction, increased cardiac activity, sodium + water retention, and increased cortisol/catecholamines
When cardiac output decreases, catecholamines are released (Epinephrine / Ne), ADH (posterior pituitary), and Angiotensin II are released
RAAS: renin released from kidneys when renal blood flow is reduced –> renin enters circulation and converts angiotensinogen from liver to angiotensin I. Angiotensin I is converted to Angiotensin II via ACE (lungs - endothelial cells)
- Angiotensin II = triggers release of aldosterone (sodium and therefore water reabsorption), and also triggers vasoconstriction –> increase in blood volume and therefore blood pressure
Catecholamines, ADH, and Angiotensin II release in attempt to cause vasoconstriction of blood vessels and increase blood volume
SYMPTOMS
⦁ hypotension (without volume = low pressure)
⦁ Tachycardia
⦁ cool / clammy skin (blood provides heat)
⦁ decreased CO –> oliguria / anuria
⦁ pale / cool dry extremities
⦁ slow capillary refill: > 2 seconds
⦁ decreased skin turgor
⦁ dry mucous membranes
⦁ altered mental status
⦁ doesn’t usually cause profound respiratory distress
DIAGNOSIS ⦁ vasoconstriction (increased SVR) ⦁ hypotension ⦁ decreased CO (anuria / oliguria) ⦁ decreased pulmonary capillary pressure
LABS
⦁ increased Hgb / Hct = due to dehydration
- decreased hgb / hct = late sign in hemorrhagic shock
⦁ decreased CVP (central venous pressure) / PCWP (pulmonary capillary wedge pressure)
PCWP = left atrial pressure
Although LV pressure can be directly measured by placing a catheter within the LV, it is not feasible to advance this catheter back into the left atrium. LAP can be measured by placing a special catheter into the right atrium then punching through the interatrial septum; however, for obvious reasons, this is not usually performed because of damage to the septum and potential harm to the patient.
So in HYPOVOLEMIC SHOCK =
⦁ loss of blood or fluid volume –>
⦁ increased peripheral vascular resistance (vasoconstriction) + increased HR to maintain CO
⦁ hemorrhagic causes = GI bleed, AAA, rupture, etc.
⦁ fluid loss causes = vomiting / diarrhea, pancreatitis, severe burns, etc.
⦁ CO = decreased ⦁ PCWP = decreased ⦁ SVR = increased ⦁ pale / cool / mottled skin ⦁ prolonged capillary refill ⦁ decreased skin turgor, dry mucous membranes ⦁ usually no severe respiratory distress
TREATMENT
⦁ ABCDEs
⦁ 2 large bore IVs or a central line
⦁ NS or LR - monitor urine output to assess success of volume resuscitation
⦁ control source of hemorrhage if present
⦁ RBC transfusion if severe hemorrhage
CARDIOGENIC SHOCK
a condition in which your heart suddenly can’t pump enough blood to meet your body’s needs. The condition is most often caused by a severe heart attack, but not everyone who has a heart attack has cardiogenic shock
- Hypotension
- Sweating
- Chest pain
- unconsciousness
Causes include heart attack, myocarditis, pulmonary embolism and endocarditis. Symptoms include rapid heartbeat, sudden shortness of breath, sweating, confusion and weak pulse. Treatment depends on the cause and may include inotropic agents, valvular repair, thrombolytic agents and heart surgery
Cardiogenic shock is the leading cause of death in acute myocardial infarction.
It is characterized by decreased cardiac output and tissue hypoxia in the presence of sufficient intravascular volume.
Patients present with hypotension, tachycardia, altered mentation, cool cyanotic extremities, faint peripheral pulses, and oliguria.
A low pulse pressure is also typically encountered.
Coronary angiography is indicated if myocardial ischemia or infarct is present.
Invasive hemodynamic monitoring may be used, the results of which show a high pulmonary capillary wedge pressure (> 15 mm Hg) and a low cardiac index (stroke volume x heart rate / body surface area; < 2.2 L/min/m2).
The cardiac index is a hemodynamic parameter that relates the cardiac output from the left ventricle in one minute to body surface area. Thus, relating cardiac performance to the size of the individual.
Treatment mainstay includes prompt inotropic medications such as dopamine, dobutamine and phosphodiesterase inhibitors, and norepinephrine.
Other measures include the placement of central and peripheral arterial lines, possible fluid resuscitation, ICU care, electrolyte and acid-base correction, intra-aortic balloon pump, percutaneous coronary intervention or coronary artery bypass grafting.
SEPTIC SHOCK
D
ANAPHYLACTIC SHOCK
D
NEUROGENIC SHOCK
D
PERICARDITIS
PERICARDITIS
Acute pericarditis = usually lasts a few weeks
Chronic pericarditis = usually > 6 months
PERICARDIUM ANATOMY
- The pericardium has 2 layers:
⦁ Serous layer (visceral + parietal layer)
⦁ Fibrous Layer
- The serous layer is made up of 2 layers: the visceral layer + the parietal layer
- there is serous fluid between them
- pericardium = visceral layer < serous cavity < parietal layer < fibrous layer
FUNCTIONS OF THE PERICARDIUM ⦁ Stabilizes heart in mediastinum ⦁ Prevents overfilling ⦁ Lubricates the heart ⦁ Protects heart from infections
- ** MC Complication = PERICARDIAL EFFUSION ***
- people with pericarditis are at risk for developing a pericardial effusion = inflammation causes fluid to accumulate around the heart - fluid is accumulating faster than it can be drained –> can compress the heart
CAUSES OF PERICARDITIS
- 2 MC causes
⦁ IDIOPATHIC (probably viral-related)
⦁ Viral (Enterovirus: Coxsackie B or Echovirus)
OTHER CAUSES OF PERICARDITIS
⦁ Dressler syndrome (post-MI pericarditis - 2-5 days after MI): cell death leads to massive inflammation that also involves the serous pericardium
⦁ Post-cardiac surgery
⦁ Neoplastic (cancer)
⦁ Radiation therapy
⦁ Uremic Pericarditis (kidney damage –> high blood urea levels (nitrogen waste product) –> deposits and irritates the serous pericardium = “buttered bread” appearance)
⦁ Auto-immune (RA, Scleroderma, SLE) - immune system attacks its own tissues, including the pericardium
⦁ Bacterial (staph / strep)
⦁ TB / sarcoidosis / amyloidosis
⦁ Medication drugs: Procainamide (anti-arrhythmic), INH, Hydralazine (vasodilator - anti-hypertensive med), PCN, certain anti-convulsants
Inflammation causes fluid and immune cells to build up in pericardial tissues –> gets thicker
CHRONIC PERICARDITIS = inflammation of the pericardium that lasts for weeks to months
- chronic inflammation –> immune cells –> fibrosis (fibrin deposits –> stiffness of pericardium) = makes it hard for the heart to expand –> decreased stroke volume / cardiac output –> tachycardia
SYMPTOMS OF PERICARDITIS ⦁ Chest Pain* = Persistent + Postural - worse with inspiration - worse when supine - relieved by sitting up + leaning forward ⦁ Fever* - usually present ⦁ Dyspnea ⦁ **Pericardial Friction Rub** - best heard when patient sitting + leaning forward
DIAGNOSIS ⦁ EKG - stage I (first days to weeks)- ST elevation in precordial leads (V1-V6) + PR depression - stage II - T wave flattening - stage III - T wave inversion - stage IV - resolution to normal
PR Elevation in AVR
PR depression everywhere else
Diffuse ST elevation
⦁ ECHO = used to assess for complications of acute pericarditis (check for pericardial effusion / tamponade)
- Isolated pericarditis = normal echo, but may see stiffness of pericardium with chronic pericarditis
Effusions = common complication of pericarditis. Tamponade = rare complication of pericarditis
⦁ Leukocytosis - elevated WBC
⦁ Elevated ESR - marker of inflammatory activity
⦁ Troponin - released when heart muscle has been damaged (normal troponin = 0 - 0.04)
Troponin levels = rise 3-4 hours after onset of chest pain, may take up to 12 hours to show elevation, peak after 18-24 hours, may remain elevated for 10-14 days afterwards
TREATMENT
⦁ 1st line = NSAIDS + Colchicine
- Aspirin or Ibuprofen or Indomethacin*** + Colchicine x 7-14 days
- Can just give indomethacin or ibuprofen or ASA, but addition of colchicine showed to be more effective
⦁ Colchicine = 2nd line; according to PANCE PREP; (1st = aspirin or NSAIDS)
⦁ Steroids - reserved for severe symptoms, refractory, and auto-immune. Reserved for severe cases that failed NSAID/ASA treatment
⦁ Dressler Pericarditis = Aspirin or Colchicine
⦁ If NSAIDS are contraindicated = Prednisone + Colchicine
Patient will present as → a 48-year-old male with type I diabetes mellitus and end-stage renal disease currently on hemodialysis with dyspnea, cough and chest pain. He describes the pain as worse during inspiration and when he is lying on his back. The patient reports significant relief oh his chest pain with sitting up or leaning forward. A basic metabolic panel is remarkable for a BUN > 60 mg/dL. On cardiac auscultation, you hear a pericardial friction rub that is heard best when the patient is upright and leaning forward. The EKG demonstrates diffuse, ST segment elevations in the precordial leads.
(uremic pericarditis)
DRESSLER’S SYNDROME
Dressler’s syndrome, or postmyocardial infarction syndrome, occurs several days to several weeks after MI. The condition is characterized by chest pain, fever, pericarditis with a pericardial friction rub, pericardial effusion, pleurisy, pleural effusions, and multiple joint pain. The cause is thought to be an autoimmune response to the damaged myocardial tissue and pericardium. The difference between Dressler’s syndrome and recurrent MI is difficult to determine; however, in Dressler’s syndrome, there is minimal or no increase in cardiac enzymes. Treatment includes the use of aspirin, NSAIDs, and, in some cases, corticosteroids.
GIANT CELL ARTERITIS (TEMPORAL ARTERITIS)
MEDIUM + LARGE VESSEL VASCULITIS
PATHOPHSYIOLOGY
- Vasculitis = typically an autoimmune disease - immune system recognizes own vasculature as foreign, and attacks (molecular mimicry) = associated with medium and large vessel vasculitis
- Mostly affects cranial arteries (head + neck)
Idiopathic +/- autoimmune viral infection causes monocyte activation and inflammatory cytokine production, inflammation and tissue destruction resulting in symptoms
- Once vessels are damaged = exposed collagen + tissue factor ==> increases chances of blood coagulation
- blood vessel walls get weaker as they are more damaged ==> higher risk for aneurysm
- as vessel wall heals = gets harder / stiffer from fibrin deposition
Vasculitis affects extracranial branches of the carotid artery: temporal artery, occipital artery, ophthalmic artery, posterior ciliary artery
- MC location for vasculitis = ** TEMPORAL REGION ** supplied by carotid arteries
⦁ Patients > 50 (if < 50 in stem = not GCA)
⦁ Women > men
** ASSOCIATED WITH POLYMYALGIA RHEUMATICA **
= inflammatory condition that causes muscle pain + stiffness in proximal muscles - neck / shoulders / upper arms / proximal legs
- stiffness in morning*
- Many patients with GCA have polymyalgia rheumatica, but not necessarily the other way around
SYMPTOMS
⦁ Throbbing unilateral Headache (temporal branch)
⦁ Severe tenderness over ipsilateral temple
⦁ Amaurosis Fugax*** / vision changes (ophthalmic artery)
⦁ Jaw claudication / pain with chewing (facial artery)
⦁ low grade fever / fatigue / weight loss / anorexia
** COMPLICATION = BLINDNESS **
** COMPLICATION = AORTIC ANEURYSM **
PHYSICAL EXAM
⦁ thickened temporal artery - sticks out
⦁ tenderness of temporal region
⦁ pulseless temporal region
DIAGNOSIS
⦁ ** ELEVATED ESR ** > 50, usually > 100
⦁ elevated CRP
⦁ normochromic normocytic anemia
⦁ Will NOT have elevated CK (creatine kinase) - which occurs with muscle breakdown (MI / Rhabdo)
(does not occur in polymyalgia rheumatica either)
- ** GOLD STANDARD = TEMPORAL ARTERY BIOPSY **
- shows giant cells in elastic lamina (between tunica intima + tunica media)
- not large single cells, but granulomas, or groups of monocytes packed tightly together to look like one giant cell
Giant cell granulomas as immune system attempts to wall off “foreign” invaders
- Giant cell arteritis = SEGMENTAL or SKIP LESIONS **
- meaning that only sections of the artery are affected, so when performing temporal artery biopsy, need to take long sections in order to see affected segments
- meaning if negative on biopsy, patient may still have GCA, and biopsy only showed unaffected area
COMPLICATIONS
⦁ blindness!!!!
- give steroids prior to biopsy, as results may take a while, and patient may be blind by then.
DO NOT WAIT FOR BIOPSY RESULTS, GIVE STEROIDS FIRST IF GCA IS SUSPECTED
⦁ Aortic aneurysm
- poor blood flow to ophthalmic artery –> ischemia –> irreversible blindness
TREATMENT
⦁ high dose steroids = PREDNISONE
- ESR used to monitor response to steroids
RULE OF 50 WITH GCA
1) Age greater than 50
2) Sed rate greater than 50
3) Steroids greater than 50 (will start patient typically on 60 mg of prednisone)
Patient will present as → a 67-year-old female with a severe throbbing headache and visual impairment in the left eye. The patient describes worsening of pain with chewing or combing her hair. Lately, she reports feeling very weak and tired especially in the mornings. At times she cannot even raise her arms to reach the cabinets in her kitchen. On physical exam, she has decreased visual acuity of the left eye, scalp tenderness on the left, and an absent pulse in the left temporal area. Laboratory testing is significant for an elevated erythrocyte sedimentation rate. She is admitted and immediately started on systemic glucocorticoids.
LEADS VS ARTERY
⦁ V1 - V4 = Anterior (V3-V4) / Septal Leads (V1-V2)
⦁ II / III / AVF = Inferior Leads
⦁ I / AVL / V5 / V6 = Lateral Leads
⦁ Anterior septal leads (V1 - V4) = LAD
= SALAD (Septal Anterior LAD)
⦁ Inferior leads (II / III / AVF) = RCA*** (70%) + Left Circumflex
⦁ Lateral leads (I/AVL/V5/V6) = Left Circumflex + LAD
⦁ Anterior wall ST elevation in leads V1 through V4
⦁ Inferior wall ST elevation in leads II, III, and AVF
⦁ Lateral wall ST elevation in leads I, AVL, V5, and V6
⦁ Posterior wall ST depressions V1 through V3
HEART BLOCKS = ATRIOVENTRICULAR BLOCKS (AV BLOCKS)
MC CAUSES OF AV BLOCK =
- Idiopathic fibrosis and sclerosis of conduction system (about 50% of patients)
- Ischemic heart disease (40%)
The remaining cases of AV block are caused by
- Drugs (eg, beta-blockers, calcium channel blockers, digoxin, amiodarone)
- Increased vagal tone
- Valvulopathy
- Congenital heart, genetic, or other disorders
First-degree and second-degree blocks are partial
Third-degree blocks are complete
o FIRST DEGREE HEART BLOCK
- PR interval > 0.20
- In a stable patient = most likely benign = needs no tx
- Unstable patient with severe bradycardia = needs pacing
o SECOND DEGREE HEART BLOCK
⦁ Mobitz I (Wenkebach)
- longer, longer, longer, drop
- PR interval gets longer, longer, longer, then QRS drops
- Treatment = unnecessary unless the block causes symptomatic bradycardia and transient or reversible causes have been excluded
In many cases, type 1 second-degree heart block is a normal variant. Other times, the etiology is likely related to increased vagal tone and in most cases requires no treatment. It can also occur in a myocardial infarction and usually resolves after the infarct period
⦁ Mobitz II
- when some Ps don’t get Qs
- P wave not followed by QRS wave (dropped)
- Almost always progresses to 3rd-degree heart block.
- TX = Patients will need a pacemaker (even if asymptomatic!)
o THIRD DEGREE HEART BLOCK (COMPLETE BLOCK)
- Ps and Qs don’t agree
- P intervals are consistent
- QRS intervals are consistent
- Ps and QRSs don’t line up
THIRD DEGREE HEART BLOCK TREATMENT ⦁ Asymptomatic - none ⦁ Symptomatic - atropine or isoproterenol ⦁ Permanent - pacemaker - TX = patients will need a pacer - need to rule out ischemic disease
SECONDARY HYPERTENSION
CAUSES OF SECONDARY HYPERTENSION ⦁ Chronic Kidney Disease ⦁ Cushing's Disease ⦁ Medications ⦁ Renal Artery Stenosis ⦁ Drugs (ETOH / Cocaine) ⦁ Hyperaldosteronism ⦁ Polycythemia Vera ⦁ Hyper / Hypothyroidism ⦁ Coarctation of the Aorta ⦁ Sleep Apnea ⦁ Pheochromocytoma ⦁ Hyperparathyroidism
MITRAL STENOSIS
Mitral Stenosis = narrowing of mitral valve
MC cause = ** RHEUMATIC FEVER **
- in MS; rheumatic fever causes inflammation/fibrosis to fuse valve leaflets together = called commisural fusion
- In MR; rheumatic fever causes inflammation/fibrosis to not properly close together
MITRAL STENOSIS
- usually normal valve area = 4-6 cm
- in MS, commissural fusion narrows valve area to 2 cm
The increased volume in the Left Atria pushing on the mitral valve –> increased pressure in LA.
Higher pressures flowing through a fibrotic valve cause an OPENING SNAP after S2, followed by a diastolic rumble as blood is forced through smaller open
Constant increased volume / pressure in the left atrium –> dilation of left atrium as well as back up of blood into the pulmonary system –> pulmonary congestion / edema –> symptoms such as Dyspnea (MC*)
Extra blood in pulmonary system causes higher pulmonary pressures (pulmonary HTN), meaning the right ventricle has to pump harder to get blood through the pulmonic valve (SL valve) –> RVH –> can ultimately lead to right-sided heart failure
With LAE, the pacemaker cells in the LA stretch and become irritable –> increased risk of A-fib (the right and left atrium don’t contract properly anymore) –> stagnant blood –> increased risk of thromboembolism formation –> can dislodge to systemic circulation
If atrium dilates and becomes really large = can compress the esophagus and lead to difficulty swallowing (dysphagia)
- MC cause of mitral stenosis = RHEUMATIC FEVER
- Rheumatic Fever can cause chronic rheumatic heart disease, leading to scarring + fusion of the valve leaflets
- 40% of patients with rheumatic heart disease get pure or predominant Mitral valve stenosis
- 2/3 of all patients with Mitral Stenosis = FEMALE
- rheumatic fever - not commonly seen in the US - mostly foreign countries, but there have been some outbreaks. Rheumatic fever first affects mitral valve, then aortic, then tricuspid, then pulmonic.
ETIOLOGIES of MITRAL STENOSIS
⦁ ** Rheumatic Heart Disease ** (mostly females)
⦁ Congenital
⦁ Left atrial myxoma
⦁ Valvulitis (rare) = Carcinoid, SLE, RA, Amyloid
PATHOPHYSIOLOGY
- narrowed mitral orifice –> obstruction of flow from LA to LV –> blood backs up into left atrium –> volume overload / increased left atrial pressure –> backs up into lungs –> pulmonary congestion –> pulmonary HTN –> CHF (heart has to work extra hard to pump blood to the lungs)
- Normal Valve area = 4-5cm
- Mild mitral stenosis = 1.5-2.5 cm with minimal symptoms
- Moderate mitral stenosis = 1.0-1.5 cm - usually does not produce symptoms at rest
- Severe mitral stenosis = < 1.0 cm
- usually takes a long time for stenosis + symptoms to occur, but can occur rapidly (acute)
- progressive lifelong disease that is usually slow/stable in early years, with progressive acceleration in later years*
- 20-40 year latency from rheumatic fever to symptom onset with mitral valve stenosis. An additional 10 years before disabling symptoms occur
SYMPTOMS of MITRAL STENOSIS o Pulmonary Symptoms ⦁ ** Dyspnea (MC) - SOB, Orthopnea, PND ⦁ Pulmonary edema ⦁ Hemoptysis ⦁ Cough ⦁ Frequent bronchitis ⦁ Pulmonary HTN
o A-Fib (secondary to atrial enlargement –> thromboembolic events (CVA)
o Right sided Heart failure = due to prolonged pulmonary HTN
o Mitral Facies = ruddy, flushed cheeks with facial pallor (chronic hypoxia)
o Signs of LAE (left atrial enlargement) = dysphagia (esophageal compression) + Ortner’s Syndrome = recurrent laryngeal nerve palsy due to compression by the dilated left atrium –> hoarseness
PHYSICAL EXAM
1) Prominent (Loud) S1 = due to delayed forceful closure of mitral valve
- may have split S2 prior to OS (opening snap)
2) OPENING SNAP (OS)**
- high pitched sound of the opening of a stenotic valve (present in both aortic and mitral stenosis)
- Valve area is proportional to S2-OS interval: the tighter the valve = will take longer to fill LV = therefore the shorter the interval
- opening snap = diastolic for mitral stenosis, systolic for aortic stenosis
(ejection click = think aortic stenosis only)
3) MID-LATE DIASTOLIC RUMBLE** @ APEX (low-pitched) - as blood is filling from LA to LV, and moving through stenosed valve
- especially in LLD position (L lat decubitus)
⦁ decreased venous return -> decreased murmur intensity (ex: Valsalva, standing, inspiration)
DIAGNOSIS
1) ECHO** = see narrowed mitral valve (increased LA pressure, may have pulmonary HTN)
2) EKG = Left Atrial Enlargement (P mitrale) = larger initial upward deflecting P wave in AVR + notched P wave in lead II
3) CXR = LAE + pulmonary congestion
- Palpation = small volume pulse, palpable S1 - tapping apex, palpable pulmonic component of S2
Auscultation = loud S1, Early-mid diastolic RUMBLE @ apex, and opening snap. The length of the murmur is proportional to severity
MITRAL STENOSIS COMPLICATIONS
⦁ atrial dysrhythmias from degree of atrial stretch causing pacemaker cells to become irritated
⦁ A-fib –> risk of embolization (related to age, presence of Afib, and previous embolic events)
⦁ CHF (right sided heart failure) - due to pulmonary HTN
⦁ Hemoptysis - from pulmonary HTN causing ruptured bronchial veins, or streaking/pink froth from pulmonary edema or infections
⦁ Endocarditis
⦁ Pulmonary Infections
MITRAL STENOSIS PATHOPHYSIOLOGY
1) left atrium has to increase pressure to push blood through narrowed valve –> Left Atrial Hypertension –> LA stretch + A-fib –> limited LV filling / limited CO
2) A-fib can lead to thrombus formation
3) LA HTN –> pulmonary interstitial edema + pulmonary HTN
⦁ passive pulmonary HTN = obligatory to preserve forward flow
⦁ reactive pulmonary HTN = leads to vascular changes to protect interstitium from edema, which leads to right sided heart failure
4) LA stretch –> A-fib leads to increased HR, which decreases LV filling. Decreased atrial “kick” –> thrombus formation + embolus
MITRAL STENOSIS EKG
⦁ LAE
⦁ RVH (due to pulmonary HTN)
⦁ PVCs - premature ventricular contractions
⦁ A-flutter and/or A-fib
- A-flutter/A-fib = more frequent in patients with mod/severe MS for several years. A-fib develops in 30-40% of patients with symptoms
Normal mitral valve = 4-5mm/4-6mm wide. Symptoms do not become apparent until valve stenosis is < 2.5 mm. Mild = 1.5-2.5, moderate = 1.0-1.5, severe = < 1.0
TREATMENT FOR MITRAL STENOSIS
⦁ surgery
- mitral valve repair or replacement (if symptomatic)
- balloon valvuloplasty / valvotomy = best in YOUNGER patients and in patients with noncalcified valves
⦁ Balloon valvuloplasty/valvotomy - effective long term improvement - the earlier it is done, the better = BEST TX IN YOUNGER PATIENTS and in patients with non-calcified valves
o Medical Management = for symptoms, but still need surgery!
⦁ Diuretics / sodium restriction for LHF/RHF
⦁ Digitalis / Digoxin / BB / CCB - to control rate for A-fib
⦁ Anticoags for A-fib to prevent thrombus formation
⦁ Endocarditis prophylaxis
Patient will present as → a 72-year-old female who presents to your office for a routine check-up. While she otherwise feels well, it has been a long time since she last received medical care. On exam her you note an apical, rumbling diastolic murmur with a split s1 that occurs following an opening snap. The rumbling is loudest at the start of diastole and is heard best at the left sternal border and apex
MITRAL STENOSIS MURMUR
Diastolic low pitched decrescendo rumbling murmur with opening snap heard best at the apex (mitral area) with a patient in a lateral decubitus position
Mechanism: When the leaflets of the mitral valve thicken, stiffen, and become distorted from the effects of rheumatic fever, the valve fails to open sufficiently in diastole.
Cause: Rheumatic heart disease
May present with: Exertional dyspnea, orthopnea and paroxysmal nocturnal dyspnea secondary to pulmonary congestion, hoarse voice, atrial fibrillation
Best heard at APEX in LEFT LATERAL DECUBITUS
MITRAL REGURGITATION
Systolic regurgitation of blood back into the LA when LV is contracting; blood being sent both to aorta and back into left atrium
CAUSES
⦁ **MC = MVP **
⦁ Rheumatic Fever
⦁ Damaged valve after heart attack or cardiomyopathy
- if papillary muscles damaged, can’t properly anchor chordae tendineae –> regurgitation
⦁ Left sided Heart Failure / Left Ventricular Dilation
⦁ collagen vascular disease: Marfan’s, etc.
PATHOPHYSIOLOGY
1) Retrograde blood flows from LV into LA, which then returns to LV during diastole
2) ==> LV volume overload ==> LA dilation
3) blood backs up into pulmonary circuit ==> increased pulmonary pressure
4) decreased cardiac output, due to diminished forward flow
CLINICAL MANIFESTATIONS
⦁ Holosystolic Murmur (lasts for entirety of systole)
⦁ BLOWING HOLOCYSTOLIC (PANCYSTOLIC) MURMUR DURING SYSTOLE @ apex
⦁ Acute pulmonary edema
⦁ dyspnea
⦁ fatigue
CHRONIC SYMPTOMS ⦁ a-fib ⦁ progressive dyspnea on exertion ⦁ fatigue ⦁ CHF ⦁ pulmonary HTN ⦁ hemoptysis
PHYSICAL EXAM ⦁ *** BLOWING, HOLOSYSTOLIC (PANSYSTOLIC) MURMUR @ APEX *** ⦁ ** radiates to the AXILLA ** ⦁ Widely Split S2 ⦁ MC cause of S3 sound
o Increased murmur = squatting, expiration, handgrip (like aortic regurgitation)
(unlike aortic stenosis = decreased with handgrip)
o Decreased murmur = Valsalva, standing, inspiration
- Radiates to the axilla
DIAGNOSIS
⦁ ** ECHO ** = shows hyperdynamic LV
⦁ EKG = LAE, LVH, may have a-fib
⦁ CXR = nonspecific, may have cardiomegaly and pulmonary congestion
TREATMENT
⦁ *** REPAIR PREFERRED over replacement **
⦁ Medications
- decrease afterload (ACEI / ARB / Nifedipine / Hydralazine)
- decrease preload (diuretics)
- Afib = Digoxin
MITRAL VALVE PROLAPSE
Mitral valve = 2 leaflets (anterior + posterior)
During systole, the mitral valve closes to prevent backflow of blood into the LA as the LV contracts to send blood to the body
MVP (mitral valve prolapse) = ** MC CAUSE OF MITRAL REGURGITATION **
MVP doesn’t always cause mitral regurgitation, but it usually does! (can have mitral regurgitation without MVP)
Mitral valve prolapse (MVP) affects 2-6% of the United States population.
Most cases are benign, however, MVP can lead to acute mitral regurgitation (MR), sudden cardiac death, infectious endocarditis and stroke
GENETICALLY INHERITED
Normal Pathophysiology
- normally, the papillary muscles and the connective tissue called chordae tendineae attached to the mitral valve keep it closed during systole, and keep it from PROLAPSING (moving backwards into the atrium)
IN MVP, the connective tissue is WEAKENED, called MYXOMATOUS DEGENERATION
- unknown why this weakening happens
- but often related to CT disorders such as
- ** MARFAN syndrome and EHLERS - DANLOS syndrome ***
Myxomatous degeneration results in elongated larger leaflet area and lengthened chordae tendineae, which can sometimes rupture, therefore allowing prolapse of the mitral valve into the left atrium
Mechanism: It is caused by an abnormal systolic ballooning of part of the mitral valve into the left atrium
SYMPTOMS OF MVP
⦁ typically asymptomatic throughout their life!
⦁ ** mid-systolic click ** as valve prolapses and is then suddenly stopped by chordae tendineae
(vs systolic ejection click with stenoses)
⦁ click may be followed by MID-LATE SYSTOLIC MURMUR
↑ Preload → ↓ murmur; ↓ preload → ↑ murmur
Anything that causes LV to be smaller will result in valve leaflets being closer together, so during systole ==> an earlier and longer murmur
(Valsalva, Standing)
Squatting = increased preload (more blood volume in heart) so LV enlarges, which also relaxes the valve leaflets farther apart. During systole, it takes longer for valves to come together ==> later and shorter murmur
symptoms of anxiety, panic attacks, palpitations, exercise intolerance, syncope and neuropsychiatric manifestations. Symptoms related to a progression into MR include dyspnea, fatigue, exercise intolerance, orthopnea and paroxysmal nocturnal dyspnea. MVP is classically described as an apical mid-systolic click which may or may not be followed by a late-systolic murmur.
o If Symptomatic ⦁ anxiety ⦁ panic attacks ⦁ palpitations ⦁ exercise intolerance ⦁ lightheadedness ⦁ syncope ⦁ chest pain worsened with exertion ⦁ orthopnea / PND
o Symptoms associated with MR progression ⦁ fatigue ⦁ dyspnea ⦁ PND ⦁ CHF
Patients with mitral valve prolapse are typically asymptomatic throughout their lives, although a wide range of symptoms is possible. When symptoms do occur, palpitations from arrhythmias are most common along with lightheadedness. Syncope is not part of this disease process
MIDSYSTOLIC EJECTION CLICK heard best at APEX (mitral area)
DIAGNOSIS ⦁ normal EKG ⦁ normal CXR ⦁ **** ECHO **** ⦁ mid-systolic click best heard at apex
PHYSICAL EXAM ⦁ low body weight ⦁ pectus excavatum ⦁ hypotension ⦁ scoliosis ⦁ kyphosis
TREATMENT
o If asymptomatic = reassurance + serial echo’s
o Patients with autonomic dysfunction =
⦁ ** trialed on beta-blockers **
⦁ counseled on caffeine, alcohol and tobacco abstinence
⦁ given a 24-hour cardiac monitor
Patient will present as → a 22-year-old female who complains of generalized, sub-sternal chest pain that is worsened with exertion. She appears anxious; she denies ETOH, tobacco and illicit drug use. You auscultate her heart and hear a mid-systolic click
MURMURS
⦁ Mitral Stenosis
- opening snap
- low-pitched diastolic decrescendo rumble
- rheumatic fever
⦁ Mitral Regurgitation
- blowing holosystolic (pansystolic) systolic murmur
(holosystolic = lasts throughout systole)
- radiates to AXILLA
- ** S3 **
⦁ Aortic Stenosis
- Crescendo-decrescendo systolic murmur
- opening snap + ejection click
- narrow pulse pressure
- radiates to CAROTIDS
⦁ Aortic Regurgitation
- soft, blowing, high-pitched decrescendo diastolic murmur
- widened pulse pressure
⦁ MVP
- mid-systolic click
⦁ click may be followed by MID-LATE SYSTOLIC MURMUR
expiration / squatting = increased murmur
inspiration / standing / Valsalva = decreased murmur
PRINZMETAL ANGINA (VARIANT ANGINA)
Prinzmetal’s angina is a condition of cyclical chest pain secondary to coronary vasospasm. Any acute angina must be evaluated and empirically treated with an anti-ischemic regimen of antihypertensive, antiplatelet and antithrombotic medications. Once the diagnosis of coronary vasospasm is made, long term management of the anginal attacks include calcium channel blockers, namely nifedipine, and long-acting nitrates like isosorbide dinitrate.
Statin medications (A) do play a role in the overall management of patients with Prinzmetal’s angina, as there is some correlation with atherosclerosis. However, statins do not work at decreasing vasospasm, and as such, they would not be a viable choice in decreasing the chest pain attacks. Nonselective beta-blockers like propranolol (C) are contraindicated in the treatment of Prinzmetal’s angina. Anticoagulants like warfarin (D) play no role in decreasing the vasospasm and subsequent angina associated with Prinzmetal’s.
Prinzmetal Angina (Variant Angina)
Patient with a history of HTN, smoking, DM, obesity, or cocaine use
Complaining of squeezing, pressure-like chest discomfort at rest
ECG will show transient ST-segment elevations and cardiac enzymes will be normal
Diagnosis is made by cardiac stress test
Most commonly caused by coronary artery spasm
Treatment is calcium channel blockers and nitrates
STABLE ANGINA
Angina = chest pain
Angina = caused by decreased blood flow, and therefore oxygen to the heart muscle
STABLE ANGINA or chronic angina = MC type of angina
MC underlying cause of stable angina = Atherosclerosis of 1 or more of coronary arteries
Other causes = anything that may cause thickened heart muscle wall = requires more oxygen
⦁ hypertrophic cardiomyopathy (HOCM)
⦁ aortic stenosis
⦁ hypertension
Usually occurs when patient has > 70% stenosis of coronary artery (70% of an artery is blocked by plaque buildup)
The small remaining opening may be enough to supply the heart with oxygen/blood during rest, but during exercise or stressful situations, when the heart demands more blood flow / oxygen ==> symptoms!
⦁ ** Subendocardial Ischemia **
SYMPTOMS OF STABLE ANGINA
⦁ Chest pain with exertion or stress
⦁ chest pain resolves with rest
⦁ pain in left arm / jaw / shoulders / back
⦁ SOB / Diaphoresis when symptomatic
⦁ Pain / symptoms last < 20-30 min! - subside with rest, or when exertion / stress resolves
Injury to cardiomyocytes = Reversible! not dead! (unlike myocardial infarction)
o EKG
⦁ ST segment depression (limited to subendocardial ischemia) in PRECORDIAL leads
o TREATMENT
⦁ Nitroglycerin (vasodilator) for acute symptoms
- for management
⦁ Beta Blocker = 1st line! (CCB = 2nd line or if black)
⦁ Statin
⦁ Aspirin - Selective (B1) = Metoprolol, Atenolol, Bisoprolol, Esmolol
- Nonselective (B1 + B2) = Propranolol, Carvedilol, Labetalol
- Nondihydropyridines (CCB that works on heart) = Verapamil (long-acting) + Diltiazem
Stable angina = relieved by rest + nitroglycerin!
CHRONIC STABLE ANGINA that remains symptomatic after BB / CCB / Nitro ==> RANOLAZINE
Ranolazine is approved for the treatment for chronic stable angina for those who have failed standard medical therapy. It has been shown to be effective in reducing anginal symptoms and improving exercise capacity when added to conventional medical therapy. Ranolazine can prolong the QT interval and it should be used with caution in patients with kidney or liver disease
Patient will present as → a 50-year-old woman with a history of hyperlipidemia and diabetes type 2 complaining of “chest pain attacks.” She says that these attacks tend to occur while walking up five flights of stairs to get to her apartment, they last for 15-20 minutes and are relieved by rest. She describes the pain as sharp and substernal. A baseline EKG is unremarkable. Suspecting the diagnosis, you perform an exercise stress EKG and observe transient ST depressions in the anterolateral leads after significant exertion
UNSTABLE ANGINA
Angina = chest pain
Angina = caused by decreased blood flow, and therefore oxygen to the heart muscle
Unstable Angina = usually caused by rupture of an atherosclerotic plaque, followed by thrombosis, occluding even more of the vessel
Clot forms on top of plaque; may not completely occlude vessel, but if it doesn’t = still even further occlusion has occurred ==> even less blood flow / oxygen to the heart
⦁ ** Subendocardial Ischemia **
= should be treated as an emergency! due to HIGH RISK OF PROGRESSION TO MI
- Unstable Angina = heart tissue is STILL ALIVE, but is starved for oxygen = Ischemic! (decreased blood flow / oxygen), not yet infarction (heart tissue has already begun to necrose / die)
SYMPTOMS OF UNSTABLE ANGINA
⦁ Chest pain with exercise/stress, and DURING REST!
⦁ chest pain DOES NOT RESOLVE with rest
⦁ pain in left arm / jaw / shoulders / back
⦁ SOB
⦁ Diaphoresis
⦁ Pain / symptoms last
Injury to cardiomyocytes = Reversible! not dead!
(unlike myocardial infarction)
⦁ does NOT show elevated cardiac enzymes (unlike infarction)
o EKG
⦁ ST segment depression (limited to subendocardial ischemia) in PRECORDIAL leads (similar to NSTEMI)
o TREATMENT
⦁ BETA BLOCKER = 1st line or CCB for prevention
All unstable angina = Antihypertensive (BB) + Statin + Aspirin
⦁ Nitroglycerin (vasodilator) = for acute if continued angina after BB or CCB therapy = for pain relief, but does not help with long-term treatment for further prevention
Unstable angina may not always be completely relieved by rest or nitroglycerin, helping to differentiate it from stable angina
Patient will present as → a 58-year-old man with a history of coronary artery disease, hypertension, and hyperlipidemia presents to an emergency department for evaluation of chest pain. He reports somewhat suddenly experiencing dull left-sided chest discomfort while at rest at home that was not relieved with taking nitroglycerin. His vital signs are T 37.1, HR 94 beats per minute, BP 133/87, and O2 saturation 97% on room air. His ECG shows no ST-segment changes; serum troponin is not elevated. His chest pain subsequently resolves and he is admitted to the cardiac service for further management.
PRINZMETAL ANGINA
(VARIANT ANGINA)
(VASOSPASTIC ANGINA)
PRINZMETAL ANGINA = Chest pain due to CORONARY ARTERY VASOSPASMS that lead to ischemia (decreased blood flow / oxygen to the heart)
Smooth muscle around coronary arteries constrict ==> reduce blood flow enough to cause ischemia
Patients may or may not have atherosclerosis
RISK FACTOR = SMOKING ***
- Others = marijuana / meth / cocaine
- tend to occur in younger patients (unlike unstable / stable angina)
Vasospastic angina (Prinzmetal) = can happen at any time, not just with exertion. Can occur at rest
- Prinzmetal Angina is associated with -
- ** SMOKING ***
** REYNAUD’S PHENOMENON **
** MIGRAINES **
*** usually AWAKENS PATIENT AT NIGHT, or OCCURS IN THE MORNING
- ** Magnesium deficiency ** = associated with Prinzmetal Angina
CAUSE OF VASOSPASM
⦁ not well understood
⦁ likely involves vasoconstrictors (like platelet thromboxane A2)
UNLIKE STABLE AND UNSTABLE ANGINA, PRINZMETA ANGINA OCCURS WHEN
- the vasospasm constricts the coronary artery so severely that ALL LAYERS of the heart wall being supplied are affected (and not just subendocardial ischemia)
= TRANSMURAL ISCHEMIA
Injury to cardiomyocytes = Reversible! not dead!
(unlike myocardial infarction)
o GOLD STANDARD FOR DIAGNOSIS = ANGIOGRAPHY **
- will have no findings
o EKG
⦁ ST segment elevation (transmural ischemia) in PRECORDIAL leads
o TREATMENT
⦁ ** CCB = 1st line ** = Diltiazem*
⦁ Nitroglycerin (vasodilator)
do NOT give beta blockers (Propranolol) = can exacerbate vasospasm in Prinzmetal’s Angina
PRINZMENTAL ANGINA = Intermittent chest pain, does not resolve with rest. EKG = ST Elevation, may or may not have elevation of cardiac enzymes
Tx = CCB + nitro for acute pain relief
vs STEMI = chest pain NOT cyclical, and would show troponin elevation
TETRALOGY OF FALLOT
Congenital heart disease is classified as either cyanotic or acyanotic. Cyanotic congenital heart disease is secondary to a right to left shunt. Tetralogy of Fallot is a cyanotic congenital heart disease that is defined by four key findings: pulmonic stenosis with right ventricular outflow obstruction, right ventricular hypertrophy, a ventricular septal defect, and an overriding aorta. Tetralogy of Fallot is the most common cyanotic heart defect. It may present up to three to four months after birth. Signs and symptoms of tetralogy of Fallot include cyanosis, poor feeding, hemoptysis, squatting to relieve symptoms, a single S2 on cardiac auscultation, and scoliosis. Patients with unrepaired tetralogy of Fallot may experience “tet spells.” These episodes typically occur during periods of stress that result in crying and breath-holding. They are defined by acute respiratory distress because of an increase in right ventricular outflow tract obstruction. The pulmonic stenosis murmur becomes weaker at these times due to increased shunting through the ventricular septal defect. Diagnosis of tetralogy of Fallot is with echocardiogram. An ECG may reveal right ventricular hypertrophy or right axis deviation. A chest radiograph will often show a boot-shaped heart due to right ventricular hypertrophy. Management of a tet spell is to decrease pulmonary resistance and increase systemic resistance to blood flow.
A crescendo-decrescendo murmur with a harsh systolic ejection quality is heard along the left upper sternal border
First, you should place the child in the knees-to-chest position.
Supplemental oxygen and morphine should be given.
Phenylephrine may be used to increase systemic vascular resistance.
Surgical therapy is the mainstay of long-term treatment for these patients.
What is the key treatment for critical coarctation of the aorta?
Answer: Prostaglandin E1 (keeps DA open)
Tetralogy of Fallot
Patient with a history of episodes of cyanosis (tet spells) and squatting for relief
PE will show pulmonic stenosis, right ventricular hypertrophy, overriding aorta, and VSD
CXR will show “boot-shaped” heart
Comments: Most common cyanotic congenital heart disease
Mnemonic: PROVe:: Pulmonic stenosis, Right ventricular hypertrophy, Overriding aorta, VSD
ATRIAL SEPTAL DEFECT (ASD)
opening between right atrium and left atrium
- how does this form?
1) Septum primum forms between atria, grows downward towards endocardial cushion
2) Ostium primum = gap between atria that closes as septum primum continues to grow downwards
3) Ostium secundum forms in septum primum higher up
4) Septum secundum forms closer to the RA next to the septum primum, covers the ostium secundum, but has its own gap further down called the Foramen Ovale
5) Makeshift valve present! - only allows blood to flow from RA to LA
Oxygenated blood from placenta through umbilical vein can then go from right atrium through the foramen ovale in the septum secundum that is lower down, then travels up to go through the ostium secundum of septum primum to get to the left atrium
at birth, the septum primum and septum secundum slap shut and close off the foramen ovale
ASD = atrial septum doesn’t close all the way; remains open even after birth
90% of ASD cases = due to ostium secundum
septum secundum doesn’t fuse properly with septum primum ===> foramen ovale doesn’t close correctly
The most common location for an ASD is a patent foramen ovale
10% of ASD cases = due to ostium secundum that doesn’t grow all the way down to the endocardial cushion (more common in Down Syndrome - ostium primum issue)
ASD = 10-15% of all congenital heart defects
ASD = MC congenital heart defect IN ADULTS**
(MC congenital heart defect overall = VSD)
ASD = 2nd MC congenital heart defect after VSD
⦁ ** 25% of all patients with DOWN SYNDROME have this type of heart defect (ASD) **
Down syndrome also associated with VSD and atrioventricular defect
* ASD ASSOCIATED WITH DOWN SYNDROME **
* ASD ASSOCIATED WITH FETAL ALCOHOL SYNDROME **
** TRICUSPID ATRESIA = ASSOCIATED WITH ASD **
Tricuspid atresia is the congenital cardiac disorder most commonly associated with an atrial septal defect.
- * CONGENITAL RUBELLA = ASSOCIATED WITH ASD ***
- Congenital rubella is a TORCH infection that can cause PDA and ASD
ASD = LEFT - TO - RIGHT SHUNT (ACYANOTIC)
- because Left sided pressure > Right sided pressure at birth, with ASD, oxygenated blood goes to the right side of the heart –> extra trip to the lungs to be oxygenated (left to right shunt = acyanotic!)
CLINICAL MANIFESTATIONS
⦁ ** FIXED SPLIT S2 *** at LEFT 3RD ICS
⦁ loud S1, widely split fixed S2 with no variance with respiration
(widely split FIXED S2)
- fixed = doesn’t vary with respirations
- fixed split S2 = ASD
- paradoxically split S2 = Aortic Stenosis
- widely split S2 = Mitral Regurgitation
Fixed split S2 = - extra blood going to right side of the heart causes a delay in the blood getting through the pulmonic valve ===> delay in pulmonic valve closure compared to aortic valve closure
⦁ SYSTOLIC MURMUR (increased blood flow across pulmonic valve - at LEFT 3RD INTERCOSTAL SPACE
- systolic ejection crescendo-decrescendo murmur at pulmonic area (left UPPER sternal border)
Widely split and fixed S2 into A2, Ps (lub, dub-dub)
Murmur: grade II-III/VI systolic ejection murmur at left 2nd or 3rd intercostal space
⦁ Increased oxygen saturation to right side of heart
- Most patients are asymptomatic or symptoms are minimal in childhood until > 30 y/o
Most patients with small ASDs are asymptomatic until the age of 30
⦁ Over 30 y/o: present with dyspnea and chest pain
⦁ Over 50 y/o present with atrial arrhythmias - afib and RVF
Infants / children - recurrent respiratory infections, failure to thrive, and exertional dyspnea
Adolescents / adults = exertional dyspnea, easy fatigability, palpitations, atrial arrhythmias, syncope, heart failure
COMPLICATIONS OF ASD
⦁ Paradoxical Embolism (Stroke)
- in case of DVT - clot could break off, enter RA/RV, and would then be worried about PE
- with ASD - clot could go from RA to LA, enter the systemic circuit, and potentially lodge in the brain
- Paradoxical = clot starts off in right side, but ends up in left side
⦁ EISENMENGER’S SYNDROME - excess blood volume on right side causes pulmonary HTN / increased right sided pressure. if right sided pressure > left sided pressure ==> cyanotic! - dyspnea - deoxygenated blood enters systemic circuit
(ASD / VSD / maybe PDA)
Smaller ASDs may close on their own, so children are often monitored for some time before surgical intervention
DIAGNOSIS
⦁ ** Echo ** = gold standard
⦁ CXR - may show cardiomegaly - dilated RA and RV, increased pulmonary markings, ** RBBB **
TREATMENT
⦁ Spontaneous closure - Smaller ASDs may close on their own in the 1st year, so children are often monitored for some time before surgical intervention
- most close spontaneously (< 3 mm)
⦁ Surgery (for larger openings) if symptomatic - plugging or patching the opening
- usually done at age 2-4
Most small centrally located ASDs (< 3mm) close spontaneously
Asymptomatic children with a small shunt require only observation and periodic echocardiography. Although these children are theoretically at risk of paradoxical systemic embolization, this event is rare in childhood. Thus, it is not standard practice to close a small, hemodynamically insignificant defect.
Moderate to large ASDs (evidence of right ventricular volume overload on echocardiography) should be closed, typically between ages 2 - 6 yr
Patient will present as → a healthy 7-year-old girl who has reached all developmental milestones. On examination, the precordium is hyperdynamic with a prominent right ventricular heave. A grade III/VI systolic ejection murmur is present in the 2nd left intercostal space (pulmonic position) with an early to mid-systolic rumble and a fixed splitting of the second heard sound (s2) during inspiration and expiration
