Cardio Flashcards
When do you see granulation tissue form after an MI? How about a scar?
Granulation tissue- 1 week (type III collagen)
Scar- 1 month (type I collagen)
Dressler syndrome
A pericarditis that arises 6-8 weeks after an MI due to production of auto-antibodies against your own pericardium
55 year old woman presents with headache, fever, muscle pain, and jaw claudication. ESR is elevated. What do you suspect?
Temporal (Giant cell) arteritis
Need to biopsy! But remember that a negative biopsy does not rule out disease, due to segmental pathology
Tx with corticosteroids
What is the most feared complication of temporal (giant cell) arteritis?
Irreversible blindness due to occlusion of the ophthalmic artery
What patients is Takayasu Arteritis seen most often in?
Young asian females
Just like temporal giant cell arteritis but is at the aortic branch points
Patient presents with HTN, abdominal pain and melena, and muscle pain (myopathy). Muscle biopsy shows transmural inflammation of mid sized arteries with areas of necrosis. What do you suspect? What is this associated with?
Polyarteritis nodosa
Associated with Hep B infection
The lungs are classically spared
Kawasaki disease
medium vessel vasculitis (coronary artery) that affects children.
S/S: CRASH and burn: conjunctival injection, rash, adenopathy (cervical), strawberry tongue, hand and foot rash/edema, and fever
→ can cause MI or aneurysm of coronary artery, leading to death
Tx: Aspirin and IVIG
Patient with a longstanding hx of smoking presents with gangrene of the fingers/toes and autoamputation of one of the fingers. What is the disease and how is the pathology?
Buerger disease:
Segmental thrombosing vasculitis that extends into contiguous veins and nerves—due to direct endothelial toxicity from tobacco or from hypersensitivity to them
55 year old male presents with sinusitis, hemoptysis and hematuria. What does this constellation of symptoms suggest?
Wegeners Granulomatosis (Granulomatosis with polyangiitis)
Small vessel vasculitis that involves nose, lungs, and kidneys
Tx with cyclophosphamide and steroids
Churg Strauss syndrome
Necrotizing granulomatous inflammation with eosinophils, involving the heart and lungs
Often associated with asthma and peripheral eosinophilia
p-ANCA or C-ANCA
- Wegener’s granulomatosis
- Microscopic granulomatosis
- Churg Strauss syndrome
- Wegener’s granulomatosis: c-ANCA
- Microscopic granulomatosis: p-ANCA
- Churg Strauss syndrome: p-ANCA
What is the most common vasculitis in children?
Henoch-Schonlein Purpura
Palpable purpura (patches) on buttocks and legs, GI pain, and hematuria following an upper respiratory tract infection (source of the IgA)
What usually precedes Henoch-Schonlein Purpura
An upper respiratory infection (source of the IgA deposits)
Kaposi Sarcoma
Vascular tumor associated with HHV-8
Purple patches, plaques and nodules on skin
Seen in HIV, immunocompromised patients
What valve disorder is seen in syphilis?
Aortic valve regurg- caused by dilation of the aortic valve root
What is the most common location of AAA?
Below the renal arteries and above the aortic bifurcation
What two medical problems lead to hyaline arteriolosclerosis?
Benign HTN and diabetes
What congenital heart defect is associated with fetal alcohol syndrome?
Ventricular septal defect
Atrial septal defect
Tetralogy of fallot
Patent ductus arteriosus
What are the consequences of a left to right shunt?
inc flow through the pulmonary circulation causes hypertrophy of pulmonary vessels and pulmonary HTN → eventually leads to reversal of shunt and causes late cyanosis (Eisenmenger syndrome)
Patient presents with Down syndrome and S2 splitting on auscultation
They have an atrial septal defect, which causes a left to right shunt.
What is a PDA associated with? What is the treatment for PDA?
Congenital rubella
Tx: indomethacin: decreases PGE and causes closure of the ductus arteriosus
When is it necessary to keep the ductus arteriosus patent?
In transposition of the great arteries - allows the two circulations to mix between pulmonary artery and aorta
Do this by giving the patient prostaglandin E (PGE)
CXR shows a boot shaped heart
Tetralogy of Fallot
Findings in tetralogy of fallot
1) stenosis of the RV outflow tract
2) RV hypertrophy
3) VSD
4) Aorta overriding the VSD
Causes a right to left shunt
What is transposition of the great arteries associated with?
Maternal diabetes
What cardiac finding is common in Turner syndrome?
Preductal coarctation of the aorta (causes lower extremity cyanosis in infants)
Also see aortic bicuspid valve
30 year old male presents with HTN of the upper extremities and hypotension of the lower extremities. You get a CXR and there is notching of the ribs. What do you suspect?
Coarctation of the aorta
Notching seen on CXR is due to engorgement of the intercosal arteries
What are some causes of dilated cardiomyopathy?
Usually idiopathic Coxsackie virus Autosomal dominant genetic condition Cocaine Alcohol abuse Pregnancy (usually late term) Drugs (Doxorubicin) Hemachromatosis
What is the genetic cause of hypertrophic cardiomyopathy?\
What disease can it be associated with?
usually due to genetic mutations in sarcomere proteins (myosin heavy chain)→ causes hypertrophy and stiffness of the LV
Associated with Friedrich Ataxia
What type of cardiomyopathy is seen in sudden death of young athletes?
Hypertrophic cardiomyopathy- causes a ventricular arrhythmia
What type of cardiomyopathy does amyloidosis cause?
Restrictive cardiomyopathy- abnormal deposition of amyloid makes the myocardium stiff and waxy
Systolic or diastolic dysfunction?:
Hypertrophic cardiomyopathy:
Restrictive cardiomyopathy:
Dilated cardiomyopathy:
Hypertrophic cardiomyopathy: diastolic
Restrictive cardiomyopathy: diastolic
Dilated cardiomyopathy: systolic
Most common cause of endocarditis in previously damaged valves (rheumatic heart disease and mitral valve prolapse)
Strep viridans
Most common cause of endocarditis in IVDA? What valve is effected most commonly?
Staph aureus
Right sided heart valves: tricuspid
Most common cause of endocarditis in prosthetic valves
staph epidermidis
Most common cause of endocarditis in patients with underlying colorectal carcinoma
strep bovis
Patient presents with erythematous nontender lesion on palms and soles, tender lesions on fingers, and splinter hemorrhages
endocarditis, due to microembolization of septic vegetations to skin vessels
- Janeway lesions: erythematous nontender lesions on palms and soles
- Osler nodes: tender lesions on fingers and toes (ouch osler)
Histology of the myocardium shows Aschoff bodies and Anitschkow cells
Characteristic of rheumatic fever
What valve is most commonly involved in rheumatic fever?
The mitral valve (less commonly involves the aortic valve)
Patient has stenotic aortic valve with fusion of the commissures as well as mitral stenosis… What likely caused this?
Rheumatic fever (not likely due to normal wear and tear seen in aortic stenosis)
What do you hear in someone with aortic stenosis?
A systolic ejection click and a crescendo-decrescendo murmur
What drug can cause dilated cardiomyopathy?
Doxorubicin (chemo drug)
Loffler syndrome
Restrictive cardiomyopathy
Endomyocardial fibrosis with a prominent eosinophilic infiltrate
What congenital heart disease is associated with a continuous “machine like” murmur?
PDA
Role of different vessels o Arteries= o Arterioles= o Capillaries= o Veins=
o Arteries= pressure vessels
o Arterioles= resistance vessels
o Capillaries= exchange vessels
o Veins= volume/capacitance vessels
Where in circulation is velocity the slowest? Why is this ideal?
Where is velocity to highest?
Capillaries- Has the greatest total cross sectional area
this is ideal because it optimizes conditions for exchange of substances across the capillary wall
The highest velocity is in the aorta- smallest cross sectional area
Which vessels have the greatest compliance? Where is there the biggest loss of compliance over time?
Veins have the greatest compliance. Arteries have the biggest loss of compliance over time.
Capillary fluid exchange o Pc: o Pi: o πc: o πi:
Pc: pushes fluid out of capillary
Pi: pushes fluid into capillary
πc: pulls fluid into capillary
πi: pulls fluid out of capillary
What forces cause edema
inc Pc, inc πi, inc capillary permeability, dec πc (dec plasma proteins)
Effect of CO2 on vessels
vasodilation (in patient with brain injury, have them hyperventilate to blow off CO2, cause vasoconstriction and dec blood flow)
When is blood flow through the coronary arteries increased?
During diastole – the heart is relaxed, there isn’t any pressure on the coronary arteries and there is increased flow
S1 heart sound
mitral and tricuspid valve closure
S2 heart sound
Aortic and pulmonic valve closure
S3 heart sound
In early diastole during rapid ventricular filling phase –> rapid flow from the atria into the ventricles
Normal in kids
Disease in adults: Associated with inc filling pressures and in dilated ventricles
S4 heart sound
In late diastole, associated with ventricular hypertrophy
What closes first, the pulmonic or aortic valve? Why?
The aortic valve closes first because pressure in the LV falls below aortic pressure before RV pressure falls below pulmonary pressure
Systolic murmurs
Aortic, pulmonic stenosis
Mitral, tricuspid regurg
Mitral prolapse
Diastolic murmurs
Mitral, tricuspid stenosis
Aortic, pulmonic regurg
Preload
End diastolic volume - the pressure in the left ventricle just before it ejects blood during systole
Afterload
The pressure the heart must overcome in order to open the aortic valve
What causes the normal splitting of the S2 heart sound during inspiration?
Inspiration causes a drop in intrathoracic pressure, which increases the venous return, increasing the RV filling (volume and time), and leads to the delayed closure of the pulmonic valve
Most common sites of atherosclerosis
abdominal aorta>coronary artery>popliteal artery> carotid artery
Virchow’s triad
1) venous trauma 2) stasis 3) hypercoagulability
What is the significance of the plateau in the ventricular action potential?
Opening of Ica channels with influx of Ca balances the K+ efflux
Myocyte contraction
What accounts for the automaticity of the SA and AV nodes?
I funny channels
(Na and K), slow spontaneous depolarization
What is the cause of aortic stenosis in people younger than 60?
Congenital bicuspid aortic valve (more susceptible to calcifications)
Patient presents with angina, syncope, and dyspnea. What do you suspect?
Severe aortic stenosis. Patient likely requires a valve replacement.
What lab value is used to diagnose heart failure? What does this do? What drug is the synthetic form of this?
BNP
Acts via cGMP to cause vasodilation, dec Na absorption at the collecting duct, and promotes diuresis
Nesiritide is a synthetic form of this and is used to treat acute HF
What types of patients is thiazide therapy contraindicated in?
People with sulfa allergies and people with gout (hyperuricemia)
Effect of thiazides on calcium levels?
Increase calcium reabsorption – can lead to hypercalcemia
Ingestion of meats and cheese (contain tyramine) while on MAO inhibitors can cause what?
What is this treated with?
Hypertensive crisis
Treat this with Phentolamine (a1 and a2 reversible blocker)
Blunt aortic injury: mechanism and most common location
- mechanism of injury involves a sudden deceleration that results in extreme stretching and torsional forces affecting the heart and aorta
- most common at the aortic isthmus (right after the branches off the aorta) which is tethered by the ligamentum arteriosum and is immobile compared to the rest of the aorta
Child with a heart defect that causes cyanosis and dyspnea that is improved with squatting
Tetralogy of Fallot (Caused by deviation of the infundibular septum)
The squatting increases SVR which decreases the R to L shunt and improves cyanosis
Patient develops endocarditis after a dental procedure. It is likely from which bacteria?
Strep viridans
Beck’s triad
Hypotension, distended neck veins, and muffled heart sounds = cardiac tamponade
Why do people become hypotensive when supine or in the right lateral decubitus position?
Compression of IVC decreases venous return → reduced preload → dec cardiac output → hypotension
“Supine hypotension syndrome”
Carotid baroreceptors/chemoreceptors are innervated by what nerve?
Aortic chemoreceptors/baroreceptors are innervated by which nerve?
Carotid = Glossopharyngeal IX
Aortic = vagus X
Order of Speed of conduction through the heart
Purkinje>Atrial Muscle> Ventricular Muscle>AV node
Involuntary head bobbing
Sign of a widened pulse pressure (usually due to aortic regurg)
o Pulse pressure is proportional to stroke volume and is inversely proportional to arterial compliance
VSD produces what heart sound?
Holosystolic murmur over the left sternal border
Most common cause of death after an MI
Ventricular fibrillation
Delta waves are seen in
Wolff Parkinson White
Ventricular pre-excitation syndrome
What does a schwann ganz catheter measure?
Pulmonary capillary wedge pressure – approximates left atrial pressure
Where is the most deoxygenated blood in the body?
The coronary sinus: because myocardial oxygen extraction is very high
What does the loss of the dicrotic notch on the cardiac pressure graph (of aortic pressure) indicate?
Aortic regurg
What is the most common cause of coronary sinus dilation?
Inc R sided heart pressure due to pulmonary HTN
Adenosine
Tx of supraventricular tachycardia- slows AV conduction
Very short acting (15 secs)
Can cause sense of impending doom, chest pain, and bronchospams
Dec effectiveness with caffeine and theophylline
Digoxin
Inhibits the Na/K ATPase in myocardial cells which increases intracellular Na –> this indirectly inhibits the Na-Ca exchanger and increases intracellular Ca
Inc calcium in the myocyte improves contractility and left ventricular systolic function
What drugs selectively vasodilate the coronary vessels?
Adenosine
Dipyridamole
What drug is the treatment of choice for a Pheochromocytoma?
Phenoxybenzamine (Tx pheo with pheoxy!)
Irreversible a1 and a2 antagonist and blocks the vasoconstrictive actions of NE
What drug(s) improve survival in heart failure patients?
B blockers
ACE-inhibitors
Ang II blockers
Spironolactone
What drug should you use in a person with Aspirin allergy that needs to prevent cardiovascular events?
Clopidogrel: prevents platelet aggregation
Cardiac auscultation: Opening snap with a mid diastolic murmur
Mitral stenosis
What drugs selectively vasodilate veins?
Nitrates like nitroglycerin and isosorbide dinitrate *there is some arteriole dilation
Congenital long QT is caused by?
A defect in ion channels
Patient has an MI and develops a pericardial friction rub after 3 days. What caused this?
Post-infarction fibrinoid pericarditis
Patient dies 1 week after an MI. What caused this?
Ventricular free wall rupture –> tamponade
Likely due to a LV pseudoaneurysm
Where does most fetal blood go?
Through the foramen ovale to the LA (a small portion goes RA → RV → pulm artery → ductus arteriorsus → aorta)
What is a complication of a patent foramen ovale:
paradoxical emboli – venous thromboemboli that enter systemic arterial circulation
Where do you see the highest decrease in pressure?
Across the arterioles – because they are the site of highest resistance
What is nitric oxide synthesized from?
Arginine and O2 (via endothelial nitric oxide synthase)
What drugs inc the risk of statin myopathy?
Fibrates
Niacin
Any drug that inhibits CYP450 (since statins are metabolized by this)
Aortic arch derivatives
1st Maxillary artery 1st arch is maximal
2nd Stapedial artery and hyoid artery Second = stapedial
3rd Common carotid and proximal part of internal carotid C is the 3rd letter of the alphabet
4th Aortic arch, right subclavian “Four = aor-ta”
“Fours” right subclavian
6th Pulmonary arteries and ductus arterious 66 looks like a pair of lungs
How does digoxin decrease HR?
By stimulating the vagus nerve (parasympathetics), causing dec in HR
Patient presents with blue gray discoloration and photodermatitis – what drug is he on and what labs need to be monitored?
Amiodarone:
Monitor LFTs, thyroid levels (can cause hyper/hypothyroidism) and pulmonary function tests (can cause pulmonary fibrosis)
What does the middle meningeal artery branch off of?
The maxillary artery (which branches off the external carotid artery)
Prostacyclin vs Thromboxane
Products of the arachidonic acid cascade (formed by COX)
- Prostacyclin: dec platelet aggregation, dec vascular tone
- Thromboxane (A2): inc platelet aggregation, inc vascular tone
Normally exist in balance of each other to maintain capillary patency and normal blood flow
In what organ are infarcts rare? Why?
The liver because it has dual blood supply (hepatic artery and portal vein)
What is pulsus paradoxus and when do you see it?
Pulsus paradoxus: dec in amplitude of systolic BO by >10 mmHG during inspiration
Pericarditis, *cardiac tamponade, asthma, COPD, croup
Hereditary pulmonary HTN
What is increased?
Treatment?
Hereditary PAH is due to an inactivating mutation in BMPR2 (AD with variable penetrance)
Increased endothelin (antagonize endothelin with Bosentan)
Causes dysfunctional endothelial and vascular smooth muscle cell proliferation → thickening and fibrosis and inc resistance → pulmonary HTN
Can progress to R heart failure (cor pulmonale)
How can there be near total occlusion of a coronary artery with no myocardial necrosis or scarring?
Slow growth rate of the occlusion allows for development of compensation via arterial collaterals around the point of occlusion
In an aortic dissection, where is the defect?
A tear in the aortic intima
Usually due to chronic HTN
Which drug can prolong the QT but has little risk of progressing to torsades?
Amiodarone
Phenoxybenzamine vs Phentolamine
Phenoxybenzamine: IRREVERSIBLE a1 and a2 blocker
Phentolamine: REVERSIBLE a1 and a2 blocker
Histo findings of giant cell arteritis
Granulomatous inflammation of the media
Patient presents with multiple telangiectasias on the skin and recurrent nosebleeds. What do they have and what is the inheritance of this?
Osler-Weber-Rendu Syndrome
AD: hereditary hemorrhagic telangiectasia – can rupture and cause hemorrhage
What cells are responsible for the formation of a fibrous cap in atherosclerosis?
Smooth muscle cells
What cells are responsible for forming fatty streaks?
Lipid laden macrophages
Young woman presents with excertional dyspnea
Think pulmonary HTN! mutation in BMPR2 leading to vascular smooth muscle proliferation
MI complications:
Day 1:
Day 1-3:
Day 3-14:
2 weeks-months:
Day 1: ventricular arrhythmia
Day 1-3: fibrinous pericarditis
Day 3-14: free wall rupture. tamponade, LV pseudoaneurysm
2 weeks-months: dressler syndrome, true ventricular aneurysm
What drug should be used to increase HDL levels?
Niacin B3 (blocks VLDL secretion and prevents lipolysis)
What drug should NOT be used in a patient with triglyceridemia?
Cholestyramine
What drug should be used to decrease LDL levels
Statins are first line
What drug should be used to decrease triglyceride levels?
Fibrates
Upregulation of lipoprotein lipase cause increase removal of triglycerides from the blood
Noninfectious causes of endocarditis? What will the pathology look like
Malignancy, hypercoagulable states, lupus
Sterile, platelet rich thrombi seen on valve
Patient presents with migratory thrombophlebitis. What do you suspect?
Visceral malignancy (pancreas, colon, lung)
Fenoldopam
Used in HTN emergency
o selective dopamine receptor agonist that increases cAMP and causes arterial dilation
o Increases renal perfusion by dilating renal arteriole and causes natiruesis
What electrolyte change do you see in myocardial ischemia? How will this look histologically?
Inc intracellular Calcium (lack of O2 means that ATP isn’t being formed, so Na/K ATPase and Na/Ca ATPase can’t work)
Histo: visualization of bands under the microscope: hypercontraction of the sarcomeres due to massive calcium influx
EKG shows ST elevation in leads II, III, and aVF. Where is the infarct?
The inferior heart – the right coronary artery
Ortner syndrome
when an enlarged left atrium compresses the left recurrent laryngeal nerve and causes horseness
Mediastinal widening on CXR
Aortic dissection
How long does it take for loss of cardiomyocyte contractility after the onset of ischemia?
60 seconds due to loss of ATP
When do atherosclerotic plaques in the coronary arteries become symptomatic and cause angina?
When they obstruct at least 75% of the luminal cross sectional area
Carcinoid syndrome effects on the heart
Can cause valvular fibrous plaques (R>L)
Libman-Sacks Endocarditis:
seen in SLE – nonbacterial, verrucous thrombi usually on mitral or aortic valve (LSE in SLE)
How does nitroprusside work and what is a significant side effect?
used for HTN emergency, causes release of nitric oxide to increase cGMP in smooth muscle to promote venous and arteriolar vasodilation
o Can cause cyanide toxicity!!
Coronary steal phenomenon
Adenosine and dipyridamole (phosphodiesterase inhibitor) are selective vasodilators of coronary vessels. When myocardial ischemia is present, these drugs cause a redistribution of blood flow to normal areas and bypass the collateral circulations → can allow for detection of ischemic areas because there is less blood flow to these areas
Eccentric Hypertrophy
Sarcomeres added in series
Seen in dilated cardiomyopathy
Concentric Hypertrophy
Sarcomeres added in parallel
Seen in pressure-overload hypertrophy (due to HTN or aortic stenosis)
When do you see Q waves?
In a transmural STEMI (usually develops over several hours)
When do you start to see histologic changes in an MI?
After 4 hours
0-4 hours: tissue looks normal
4-12 hours: early coagulation necrosis, edema, hemorrhage, wavy fibers
12-24 hours: coag necrosis and marginal contraction band necrosis
1-5 days: neutrophilic infiltrate
5-10 days: macrophages phagocytose dead cells
10-14 days: granulation tissue and neovascularization
2 weeks to 2 months: collagen deposition and scar formation
How to assess the severity of mitral stenosis
The best indicator of mitral stenosis severity is the length of time between S2 (the A2 component) and the opening snap of the stenotic valve: as mitral stenosis worsens, left atrial pressure increases due to impaired movement of blood into the left ventricle. Higher pressure causes the valve to open more forefully and as a result, the A2-O2 interval becomes shorter
What type of arteriolosclerosis do you see in severe HTN?
Hyperplastic: onion skinning with proliferation of smooth muscle cells
Dopamine receptors
D1: Gs
D2: Gi
Dopamine doses and effects
Low dose: D1 receptors – inc renal blood flow
Med dose: B1 receptors – cardiac activation
High dose: a1 receptors – pressor effects
