2 - Cardiac Patho Flashcards
What is chronic venous insufficiency?
Persistent ambulatory lower extremity veous hypertension
Why do venous stasis ulcers occur?
Venous hypertension, circulatory stasis and tissue hypoxia create inflammatory reaction that leads to necrosis
What is a thromboembolus?
A thrombus that has come detached and is floating freely
Virchow’s Triad
- Venous Stasis
- Venous intimal damage
- Hypercoaguable state
Which inpatients are at particularly high risk of DVT?
Pts with malignancy (esp ovarian and pancreatic)
Pregnant Women
Why do venous clots occur during stasis?
Clotting factors and platelets accumulate around venous valves and form clots
Up to 1/3 of DVT patients develop _______
Post-thrombotic Syndrome
chronic, persistent pain, edema and ulceration of affected limb
Superior Vena Cava Syndrome
progressive compression of the SVC leads to venous distention in the upper extremities and head
What is an aneurysm?
Localized dilation or outpouching of a vessel wall or cardiac chamber
True vs False Aneurysm
True: involves all three layers of the vessel wall
False: extravascular hematoma that communicates with the invtravascular space
Why is the aorta particularly prone to aneurysms?
constant stress on the vessel wall
absence of vasa vasorum in medial layer
Ventricular wall aneurysms are usually caused by what?
Dead portions that are thin and weak and stretch with contraction. Gradually becomes stronger with remodeling, but will continue to bulge and create a resevoir of blood that isn’t ejected with systole
Symptoms of cardiac aneurysms
Dysrhythmias
Heart Failure
Embolisms to brain etc
Symptoms of thoracic aneurysms
Dysphagia
Dyspnea
What are the goals of aneurysm treatment?
Low blood volume
Low blood pressure
Compare Type A and Type B Aortic dissections
A: Ascending Aorta
B: Any other portion of the aorta
Which disease are associated with valvular thrombi?
Endocarditis
Rheumatic Heart Disease
Where do PEs usually originate?
R heart
Lower Extremities
What is Buerger Disease?
Thromboangiitis Obliterans
Idiopathic. Autoimmune.
Thrombi filled with inflammatory and immune cells disrupt arterial flow
What is Raynaud Disease?
Primary Raynaud’s
Imbalance between endothelial vasodilators and vasoconstrictors
Vasospams in the small arteries and arterioles of the fingers
What is Raynaud Phenomenon?
vasospasm 2/2 systemic disease (scleroderma)
chemo, cocaine, pHTN, malignancy
Lots of things that alter endothelial function can cause Raynaud’s Phenomenon
What’s the difference between ateriosclerosis and atherosclerosis?
Arteriosclerosis is a hardening of the arterial wall, and has several causes, one of which is Atherosclerosis
Atherosclerosis is caused by accumulation of lipid-saturated macrophages in the arterial wall which form a plaque
When is an atherosclerotic plaque considered unstable?
prone to rupture even before they affect blood flow, so will be completely silent until they rupture
What causes plaque rupture?
Inflammatory mediators in the matrix are activated
Cells inside the plaque undergo apoptosis
this causes hemorrhaging within the plaque
The plaque ruptures
What are the three lipoprotiens synthesized in the liver?
VLDLs (triglyceride and protein)
LDLs (cholesterol and protein)
HDLs (phospholipids and proteins)
What are adipokines?
How are they related to CAD?
Hormones released from adipose cells
adiponectin and leptin
Associated with endothelial damage and obesity related disease
Why are CKD patients prone to CAD?
Dyslipidemia
Endothelial dysfunction
vascular calcification
Increased levels of growth factors and ROSs
Which drugs can increase risk for CAD?
NSAIDs
Antirejection drugs
Protease inhibitors
What percent narrowing of a main coronary artery can alter cellular metabolism?
50%
How long does it take for a myocardial cell to become ischemic after occlusion?
10 seconds
How long are cardiac cells viable after occlusion?
20 minutes
What usually causes stable angina?
Chronic atherosclerosis
What causes chest pain?
Buildup of lactic acid or abnormal stretching of myocardial cells
Where do the afferent sympathetic fibers of the heart enter the spinal cord?
C3-T4
That’s why chest pain can manifest as soooo many different types of radiating pain
What is microvascular angina?
50% of women with Myocardial ischemia have this
caused by intramyocardial areteriole spsm
Won’t show any evidence of coronary artery disease on a cath
What is prinzmetal angina?
Unpredictable and exclusively at rest
Often occurs during REM
Caused by vasospasm
Tx: Calcium channel blockers, long acting nitrates
What is xanthelasmas?
Small fat deposits
If these are found around the eyelids, indicative of CAD
What does it mean if xanthelasmas are found around the arcus senilis of the eyes?
yellow lipid ring around the cornea
suggest atherosclerosis/CAD
When does unstable angina occur?
when fissuring or superficial erosion of the plaque leads to intermittent thrombotic vessel occlusion and vasoconstriction
It means the plaque has started rupturing and and infarction may follow
Three hallmarks of unstable angina:
- new onset
- occurring at rest
- increasing in severity or frequency
What kind of infarction causes an NSTEMI?
Subendocardial
What kind of infarction causes a STEMI?
Transmural
When are ECG changes visible after hypoxia?
30-60 seconds
Ischemic Preconditioning
Recurrent smaller episodes of myocardial ischemia actually have a protective/adaptive effect
causes changes in ROS, calcium ions, adenosine, bradykinin and opiods and protects the myocardium!
In hypoxic settings, the cells loses which ions?
The ones that have to be pumped in:
K, Ca, Mg
What do ischemic myocardial cells release?
Catecholamines (norepi/epi)
causes a lot of the altered sympathetic/parasympathetic symptoms (dysrhythmias etc)
Why do people often have hyperglycemian within an hour of an MI?
Catecholamines released by dying myocytes
(particularly norepinephrine)
Why is angiotensin II released during MI?
Released locally from the vascular smooth mm cells
What causes myocardial stunning?
Can occur in any either MI or cardiac surgery (anytime the heart is hypoxic and then reperfused)
Caused by alterations in electrolyte pumps, calcium homeostasis, and release or ROSs.
What is hibernating myocardium?
Tissue that is persistently ischemic and actually is able to metabolically adapt and preserve myocytes until perfusion can be restored!
What medications are used to treat acute pericarditis?
Colchicine (to prevent fibrosis)
NSAIDs
What is pulsus paradoxus?
ABP during expiration is higher than ABP during inspiration by > 10mmHg
What are most common s/s of tamponade?
dyspnea, tachycardia, JVD, pulsus paradoxus
CVP EQUAL TO PAD?
What is the most accurate and reliable means of diagnosing a pericardial effusion?
ECHO
Constrictive pericarditis was once synonymous with _________
Tuberculosis
What happens in constrictive pericarditis?
How is it treated?
Pericardial layers become fibrotic and adhere, encasing the heart in a rigid shell
Fluid/Na restriction
Anti-inflammatories
Pericardiectomy
Does Dilated cardiomyopathy cause Systolic or Diastolic dysfunction?
systolic
Hypertrophic Obstructive Cardiomyopathy
Most common inherited form of LV Hypertrophy
Thicken septal wall causes LVOT obstruction during exercise or at rest
Hypertensive/Vavular Hypertrophic Cardiomyopathy
HTN and Ao stenosis cause hypertrophy in LV
Initially diastolic, then systolic dysfunction
What causes restrictive cardiomyopathy?
Scleroderma, amyloidosis, sarcoidosis, lymphoma
Myocardium becomes rigid and non-compliant d/t pathologic deposits
Usually need LVADs and and heart transplant
Why does endocarditis lead to valve problems?
The valves are continuous with the endocardium. An infection there leads to an infection of the valves
What is the most common valvular abnormality?
Aortic Stenosis
Top 3 causes of Ao Stenosis
Aging
Congential Bicuspid Valve
Rheumatic HD
What is the most common form of rheumatic heart disease?
Mitral Stenosis
Mitral Stenosis Heart Sounds
Rumbling decrescendo diastolic murmur
May have an opening snap
Aortic Regurgitation Heart Sounds
Diastolic Decrescendo Murmur
Corrigan Pulses and prominent carotid pulsations are caused by what valve problem?
Aortic Regurgitation
Regurgitation of the A-V valves causes blood to flow back into the _________
Atria
Mitral Regurgitation Heart Sounds
Loud Pansystolic mumur
Radiates into back and axilla
Mitral valve prolapse causes the cusps to billow into the ________ during systole
Atria
Acute rheumatic fever is most common in what age group?
5-15 years
The only group A B-hemolytic strep infections that can cause acute rheumatic fever arise from the _______
pharynx
Skin infections do not progress to ARF
What are aschoff bodies?
Fibrinoid necrotic deposits in the myocardium
Caused by RHD
What pathogen is most commonly responsible for infective endocarditis?
Staph Aureus
Altered formation of _________ can lead to ASDs, VSDs, and other defects
endocardial cushions
Name the three fetal shunts
Foramen Ovale
Ductus Arteriosus
Devtus venosus
The umbilical arteries carry _____ blood ______ the fetus
deoxygenated
away from
The umbilical vein carries _______ blood ______ the fetus
oxygenated
toward
When oxygenated blood exits the umbilical cord, where does it go first?
The fetal liver
What is the function of the ductus venosus?
Blood arrives first in the liver, then half the flow is diverted away from the liver through the ductus venosus and into the IVC
What happens when oxygenated blood from the fetal IVC arrives at the RA
Since it has a much higher pulsatile pressure than the deoxygenated blood that’s returning to the RA via the SVC, it shunts through the patent foramen ovale into the Left Atrium and then into the LV and Aorta
Approximately 2/3 of the blood that exits the fetal Aorta goes to _______
The head and upper extremities
What happens when deoxygenated blood in the fetal SVC reaches the RA?
Lower pressure, so instead of shunting through the foramen ovale it flows into the RV
Some of it flows into the pulmonary artery,
But most flows through the ductus arteriosus and into the descending aorta s
What happens to PVR and SVR at a baby’s first breath?
PVR decreases
SVR increases
Once the umbilical cord is clamped, flow through ________ falls instantly
ductus venosus
After _____ days, no fetal shunting is noted through the ductus venosus
7
Once the ductus venosus closes, it forms _______
round ligament of the liver
(ligamentum venosum)
What causes the foramen ovale to close?
Increased L atrial pressure
What might cause a PFO?
pulmonary HTN
RV failure
Tricuspid atresia
What is responsible for closing the ductus arteriosus?
Increased oxygen saturation in the systemic arterial blood causes vasoconstriction
How long until the ductus arteriosus is completely closed?
several weeks after birth
What conditions may cause PDA?
conditions that cause decreased PaO2
cyanotic heart disease
increased levels of vasodilating substances in the blood
What happens to oxygen consumption in a neonate at birth?
It doubles
Why do neonates have such a small cardiac reserve?
Stroke Volume is Fixed
O2 consumption doubles at birth
By two months old cardiac reserve increases. Why?
Stroke volume increases and heart rate decreases
oxygen consumption is decreased by half
How often is the underlying cause of CHD known?`
10% of the time
What percentage of Downs infants have CHD?
50%
Usually VSD or AV canal defect
What is the predominant cause of symptoms in pediatric heart failure?
pulmonary overcirculation
which symptoms commonly manifest in infants with HF?
poor feeding/FTT
Dyspnea tahcypnea diaphoresis
retraction grunting nasal flaring
Which symptoms will not manifest in infants with HF, no matter how severe the disease?
wheezing, coughing, rales
Do infants with heart failure develop peripheral edema?
No
How does H&H affect cyanosis?
Anemic infants may not appear cyanotic even when PaO2 is low
Polycythemic infants may appear cyanotic even at normal PaO2
Eisenmenger Syndrome
Conversion of a L-to-R septal shunt to a R-to-L septal shunt due to increased PVR
What are the cyanotic heart defects?
Tetralogy of Fallot
Single Ventricle
Transposition of the Great Arteries
Which defects increase pulmonary blood flow?
PDA
ASD
VSD
AVC defect
Which defects decrease pulmonary blood flow?
Tetralogy of Fallot
Tricuspid Atresia
What kind of shunting occurs with a PDA?
L to R
From Aorta to the pulmonary Artery
What are the manifestations of a PDA?
Continuous machinery murmur
bounding pulses
active precordium with palpable thrill
S/s Of pulmonary overcirculation
What are the manifestations of an ASD?
Usually asymptomatic
Crescendo-decrescendo systolic ejection murmur
What is an Atrioventicular Canal Defect?
Nonfusion of the endocardial cushions
Abnormalities in both atrial and ventricular septa and AV valves
What are the four defects of ToF?
Large VSD
Overriding Aorta
Pulmonary Stenosis
RV hypertrophy
List the obstructive defects
Coarctation of the Aorta
Aortic Stenosis
Pulmonic Stenosis
What is TGA?
Transposition of Great Arteries
Aorta comes off the RV
PA comes off the LV
What must also be present in order for TGA to be compatible with life?
PDA, ASD, or VSD
Total Anomalous Pulmonary Venous Connection
Pulmonary Veins abnormally connect to the right side of the heart
Must also have an ASD
Truncus Arteriosus
Failure of the large embryonic artery to divide into the PA and Aorta
Must have a VSD
Hypoplastic Left Heart Syndrome
L side of the heart is underdeveloped,
Must have a well developed RV and a PDA and ASD
Kawasaki Disease
Inflammatory vasculitis that leads to scarring of vessels and stenosis of the coronary arteries
Systemic HTN in children is defined as:
SBP and DBP greater than 95th percentile for age and sex on three occasions
What is usually the cause of hypertension in children?
Renal disease or CoA
