Cardiomyopathy Flashcards
what is ischemic cardiomyopathy
HF following severe CAD, not a true cardiomyopathy
describe the dysfn in DCM
cardiac dilation and systolic dysfn, usually w/ hypertrophy and HF
some causes of DCM (6)
genetic, viral myocarditis, hyperthyroidism, EtOH, doxorubicin, peripartum
pathophys of genetic DCM
mostly autosomal dominant, usually cytoskeleton protein abnormalities
pathology of DCM
enlargment of all chambers, poor contractile fn expsoses to mural thrombosis and embolism
histo of DCM
myocyte hypertrophy, interstitial fibrosis, wavy fibers
characteristics of hypertrophic cardiomyopathy (HCM)
massive hypertrophy, abnormal diastolic filling (stiffened, less compliant), sometimes intermittent outflow obstruction
etiology of HCM
genetic usually AD w/ variable penetrance and expression
prognosis depends on mutation
patho of HCM
severe hypertrophy usually in LV or septum, massive cardiomegaly, systolic outflow obstruction, no dilation but LA could dilate
histo of HCM
severely hypertrophied myocytes, in disarray w/ abnormal branches and excess fibrosis
describe infiltrative cardiomyopathy
decrease in ventricular compliance resulting in impaired diastolic filling, most common caused by amyloidosis, hemochromatosis, sarcoidosis, fibrolatstosis
describe the amyloid subtype of ICM
congo red positive (green amyloid), myocyte atrophy and subendocardial deposits
hemochromatosis subtype of ICM
accumulation of iron leads to cardiomegaly w/ excess myocyte hemosiderin and interstitial fibrosis
what is endocardial fibroelastosis
happens to kids under 2, fibroelastic tissue in endocardium either focal or diffuse, assoc w/ AV obstrtuction
what viruses are involved w/ myocarditis and thus DCM
coxsackievirus B, parvovirus B19, echovirus, HIV
clinical manifestations of DCM
same as w/ left and right HF, arrythmias which can cause sudden death
Dx of DCM
xray: cardiomegaly
EKG: shows LVH
Echo: can see dilated chambers and reduced EF
cath/stress test: to rule out CAD
Tx of DCM
underlying causes- tachy, EtOH, hyperthyroid)
HF tx (ACEi, Beta blockers, aldosterone antagonists, resynch therapy
ICD for arrhythmia prevention
Dx criteria for HCM
LV thickness >15 mm
fam history or genetic mutation
exclude things like HTN
HCM during systole
usually normal contractility until late, lower chamber volume w/ outflow obstruction
cause of HCM outflow obstruction
acceleration of flow through narrowed track brings anterior leaflet near the septum, Systolic anterior motion of the leaflet obstructs
limits CO, can lead to MR
changes in HCM outflow obstruction
anything that reduces ventricular volume will worsen the obstruction
Sx of HCM
dyspnea, angina, palpitations, sudden death
HCM and HF
decreased compliance leads to less filling and HF, dyspnea from increased atrial and pulmonary pressures- pulmonary edema
HCM and angina
increased demand from increased muscle mass
less supply from compressed coronary microvasculature
HCM and syncope
can be from arrhythmias or insufficient CO (outflow obstruction)
sudden cardiac death and HCM
from arrythmias (fibrosis, disarrayed myocytes)
increased risk w/ fam history, syncope history, wall thickness >300
prevented w/ ICD
physical exam of HCM
S4 gallop, outflow murmur w/ outflow obstruction, could have MR also for same reason
differentiating AS and HCM murmurs
AS is fixed obstruction, HCM is dynamic
increase in preload (squatting) increases AS murmur
decrease in preload (valsalva) increases HCM
HCM on EKG
LVH and T wave inversions
gold standard for HCM dx
echo
use of MRI w/ HCM
can tell how much fibrosis, this predicts severity and arrhythmia risk
medical tx of HCM
mainly targeting angina- reduce demand w/ beta blockers (first line) and CCBs
prevention of SCD
limit exercise, no sports
ICD with multiple risk factors
procedural tx for HCM
myectomy- gold standard (remove myocardium) and alcohol septal ablation (controlled MI)
primary and late manifestation of ICM
primary is increase in diastolic ventricular pressure, causes venous congestion and Right HF sx
later is a decrease in CO
echo for ICM
marked hypertrophy w/ very large atria
EKG of ICM
low voltage (despite echo hypertrophy) and pseudoinfarct Q waves
clinical manifestations of amyloid ICM
severe diastolic dysfn, heart block/arrhythmias, postural hypertension, stroke
tx for amyloid ICM
bone marrow transplant if AL, heart transplant if hereditary
standard HF drugs not effective
define sarcoidosis
granulomatous disorder w/ multiple organs (typically lymph nodes and lungs) w/ unknown etiology
clinical manifestations of sarcoid ICM
asymptomatic, conduction system disease, ventricular arrythmias, systolic HF
Tx for sarcoid ICM
glucocorticoids, HF therapies, pacemaker/ICD, transplant
cause of arrhythmogenic RV cardiomyopathy
fibrofatty infiltration of RV causing ventricular arrhythmias
clinical manifestations of ARVD
arrhythmias and SCD
Tx of ARVD
no athletics, ICD when high risk
