Cardiac Pathology Part I Flashcards
what valvular changes occur with age?
fibrous mitral valve –> atrial dilation and arhythmia
calcium deposits –> aortic stenosis and CHF
lambl excrescenses
what changes occur to the chambers of the heart with age?
left ventricular hypertrophy secondary to HTN
atrial dilation
what atherosclerotic changes occur with age?
stenosis –> MI, aortic dissection, etc.
what changes occur to the epicardium and myocardium with age?
increased epicardial fat lipofuscin accumulation basophilic degeneration myocyte loss amyloid deposition –> senile amyloidosis –> CHF
what causes pump failure?
inadequate contraction (systole) inadequate filling (diastole)
what causes flow obstruction?
increased resistance pressure (stenosis, HTN)
decreased blood flow (atherosclerosis, ischemia)
what causes regurgitant flow?
incompetent valve
what causes shunted flow?
congenital disease (VSD, ASD or PDA) post-MI
what causes cardiac conduction abnormalities?
ischemic injury
heritable arrhythmias
what causes vessel rupture?
aortic dissection
trauma (MVC)
what occurs with MVC trauma reguarding the heart?
blow to the chest may cause tearing of the ligamentum arteriosum
results in aortic dissection
what is the most important measurement in cardiomegaly?
weight NOT wall thickness
what is congestive heart failure (CHF)?
progressive pump failure causing poor blood delivery
diastolic –> inability to fill ventricles
systolic–> inability to empty ventricles
what causes systolic dysfunction?
ischemic injury
dilated cardiomyopathy
valve regurgitation
what EF changes are consistent with systolic dysfunction?
decreased EF
what causes diastolic dysfunction?
HTN --> LVH aortic stenosis --> LVH hypertrophic cardiomyopathy fibrosis restrictive cardiomyopathy
what EF changes are consistent with diastolic dysfunction?
normal EF but lower total volume due to less filling
what causes left CHF?
myocardial ischemia
HTN
left valve disease (aortic/mitral)
what is the clinial presentation of left CHF?
pulmonary congestion (crackles) low tissue perfusion paroxysmal nocturnal dyspnea orthopnea dyspnea on exertion cyanosis confusion due to low cerebral perfusion azotemia due to low renal perfusion
what would be seen on CXR for a patient with left CHF?
Kerley B lines
what histologic findings would be seen on a patient with left CHF?
hemosiderin-laden macrophages
what is the most common cause of right CHF?
left CHF
*increases pulmonary pressure which results in right CHF
what causes isolated right CHF?
parenchymal lung disease (most common)
lung thromboemboli
primary pulmonary HTN (rare)
what is the clinical presentation of right CHF?
HSM (nutmeg liver) distended veins LE edema exertional dyspnea ascites weight gain
what is the most common congenital heart disease?
septal defects (ASD or VSD)
which septal defect is most common?
VSD
what is the most common cause of genetic heart disease?
Down syndrome
what defects are associated with down syndrome?
VSD or ASD
what is marfan syndrome and what cardiac defects are associated with it?
Fibrillin-1 mutation causing defective TGF-B activity
aortic aneurysm
aortic dissection
mitral or aortic valve prolapse
what is DiGeorge syndrome?
CATCH-22
cardiac abnormalities abnormal facies thymic aplasia cleft palate hypocalcemia 22q11 deletion
what cardiac defects are associated with DiGeorge syndrome?
tetrology of Fallot
transposition of great vessels
ASD
VSD
what cardiac defects are associated with Turner syndrome (45, XO)?
coarctation of the aorta
what cardiac defects are associated with Trisomy 18 and 13?
PDA
VSD
ASD
what are examples of a left-to-right shunt?
ASD
VSD
PDA
how do patients with a left-to-right shunt present?
asymptomatic without cyanosis
what are examples of a right-to-left shunt?
Tetralogy of Fallot
Transposition of the great arteries
Tricuspid atresia
how do patients with a right-to-left shunt present?
cyanosis
hypertrophic osteoarthropathy
hypoxemia
what is a paradoxical embolus?
a venous embolism that passes through an ASD or VSD and gains access to arterial circulation
when can a paradoxical embolus occur?
during a L-R shunt when a pressure differential occurs (valsalva, BM, coughing, sneezing)
VSD, ASD, PDA or PFO
what are the clinical features of ASD?
usually asymptomatic until adulthood
ejection systolic murmur
low mortality
what are the clinical features of VSD?
holosystolic murmur
effects depend on size and presence of other heart defects:
- symptoms as children often have other defects
- 50% close spontaneously
if a VSD large enough, what can occur?
right ventricular hypertrophy
pulmonary HTN
shunt reversal (Eisenmenger syndrome)
what is shunt reversal/Eisenmenger syndrome?
- L-R shunt
- increased pulmonary blood flow
- endothelial dysfunction and pulmonary vascular remodeling
- increase in pulmonary vascular resistance
- inversion of shunt (R-L)
- poorly oxygenated blood enters systemic circulation
what might cause a ductus arteriosis to remain open?
infant hypoxia
defects associated with increased pulmonary vascular pressure (VSD)
what is heard on ausculation with a PDA?
harsh, machinery-like murmur
what is tetralogy of fallot?
R-L shunt
- VSD
- R ventricular hypertrophy
- pulmonary valve stenosis
- overriding aorta
what is the clinical presentation of ToF?
cyanotic at birth
VSD causes holosystolic murmur
pulmonic stenosis causes systolic ejection murmur
Tet spell = cyanosis/syncope during emotional distress
compensatory squatting
what can be seen on CXR in ToF?
boot shaped heart
concave pulmonary arterial segment
what is transposition of the great arteries?
aorta and pulmonary artery swap places
incompatible with life unless shunt is present (VSD, PDA or PFO)
presents as cyanosis and trouble breathing
what can be given at birth to keep a ductus arteriosis open?
prostaglandin E1
what is tricuspid atresia?
complete occlusion of the tricuspid valve
oxygenation must be maintained by an ASD/PFO AND a VSD
severe cyanosis at birth
high mortality
what is the infantile form of coarctation of the aorta?
coarctation with a PDA
cyanosis in the lower half of the body
absent femoral pulses
heart failure/shock
what is the adult form of coarctation of the aorta?
coarctation without PDA
usually asymptomatic
HTN in UE, hypo in LE
possible concentric left ventricular hypertrophy
what can be seen on CXR with coarctation of the aorta?
rib notching
what is the result of aortic stenosis/atresia?
left ventricular hypertrophy
seen in hypoplastic left heart syndrome
what are the primary causes of ischemic heart disease?
artherosclerosis (>90%)
coronary artery emboli
vasculitis
vessel spasm
what are the clinical features of MI?
prolonged substernal CP (crushing, stabbing, squeezing) radiation to neck, shoulder or jaw rapid, weak pulse profuse sweating nausea and vomiting dyspnea
what are the most sensitive and specific biomarkers for myocardial damage?
Troponin T and I
what other biomarkers can indicated myocardial damage?
CK-MB
CK
Myoglobin
what is the time to elevation of Troponin and CKMB?
3-12 hours
peak at 24 hours
what is the time to normalization of Troponin and CKMB?
CKMB back to normal in 48-72 hrs
Troponin >5 days
why is it important to get serial troponins?
a person can present with an acute MI without having elevated cardiac enzymes
EKG is diagnostic at this time
what are the transmural infarcts?
LAD
Left circumflex
Right coronary
what area of the heart is affected by a LAD infarct?
anterior apex
what area of the heart is affected by a circumflex infarct?
lateral left ventricle
what area of the heart is affected by a right coronary infarct?
right posterior
what causes subendocardial infarcts?
reperfusion of transmural infarct (regional) global hypotension (circumfrential)
what causes microinfarcts?
small intramural vessel occlusion
COCAINE!!
what morphologic changes are seen 30 mins-4 hrs post-infarct?
waviness of fibers
what morphologic changes are seen 4-12 hrs post-infarct?
edema
early coagulative necrosis
what morphologic changes are seen 12-24 hrs post-infarct?
monocyte hypereosinophilia
contraction band necrosis
what morphologic changes are seen 1-3 days post-infarct?
coagulation necrosis with loss of nuclei
neutrophil infiltration
what morphologic changes are seen 3-7 days post-infarct?
phagocytosis of dead cells with macrophages
what morphologic changes are seen 7-10 days post-infarct?
granulation tissue
what morphologic changes are seen 10-14 days post-infarct?
collagen deposition
*collagen formation continues until scar is fully formed at 2 months post-infarct
what are the early complications (24 hrs) associated with MI?
life threatening arrhythmias (V fib)
cardiogenic shock
what are the intermediate complications (2-4 days) associated with MI?
myocardial rupture (septal, free wall or papillary) acute pericarditis and tamponade
what are the late complications (2 weeks+) associated with MI?
Dressler syndrome
ventricular aneurysm
life threatening arrhythmias
progressive CHF
what is Dressler syndrome?
fibrinous pericarditis due to immune reaction to myocardial proteins in the blood
what is the clinical presentation of Dressler syndrome?
fever
pleuritic pain
pericardial effusion
what is angina pectoris?
transient, recurrent CP induced by myocardial ischemia
pain caused by release of adenosine and bradykinin
what is stable angina?
stenotic occlusion of coronary artery
induced by physical activity or stress
relieved by rest or vasodilators
what is prinzmental variant angina?
episodic coronary artery spasm
relieved with vasodilators
unrelated to physical activity, HR or BP
what is unstable angina?
present at rest
crescendo pattern of pain
usually caused by rupture of artherosclerotic plaque with partial thrombus
what EKG pattern and tropinin levels will be seen with stable angina?
normal EKG
normal troponins
what EKG pattern and tropinin levels will be seen with unstable angina?
normal or inverted T waves or ST depression on EKG
normal troponins
what EKG pattern and tropinin levels will be seen with NSTEMI?
normal or inverted T waves or ST depression on EKG
elevated troponins
what EKG pattern and tropinin levels will be seen with STEMI?
hyperacute T waves or ST elevation on EKG
elevated troponins
