Contractile dysfunction seen in which type of cardiomyopathy?
ANSWER: (A) Dilated > (B) RestrictedREF: Harrison's 18th ed ch: 238"Although restriction of contractility may be seen in both dilated as well as restrictive cardiomyopathy, its characterstic of dilated cardiomyopathy where as diastolic dysfunction is characterstic of restrictive cardiomyopathy"Dilated cardiomyopathy:An enlarged left ventricle with decreased systolic function as measured by left ventricular ejection fraction characterizes dilated cardiomyopathy. Systolic failure is more marked than the frequently accompanying diastolic dysfunction, although the latter may be functionally severe in the setting of marked volume overload.Restrictive cardiomyopathy:Characterized by abnormal diastolic function, often with mildly decreased contractility and ejection fraction (usually >30-50%). Both atria are enlarged, sometimes massively. Modest left ventricular dilation can be present, usually with an end-diastolic dimension <6 cm. End-diastolic pressures are elevated in both ventricles, with preservation of cardiac output until late in the disease.Hypertrophic cardiomyopathy:Hypertrophic cardiomyopathy is characterized by marked left ventricular hypertrophy in the absence of other causes, such as hyper tension or valve disease).The systolic function as measured by ejection fraction is often supranormal, at times with virtual obliteration of the left ventricular cavity during systole. The hypertrophy may be asymmetric, involving the septum more than the free wall of the ventricle.Approximately one-third of symptomatic patients demonstrate a resting intraventricular gradient that impedes outflow during systole and is exacerbated by increased contractilityPRESENTATION WITH SYMPTOMATIC CARDIOMYOPATHY DilatedRestrictiveHypertrophicEjection fraction (normal 55%)Left ventricular diastolic dimension (normal < 55 mm)Usually <30% when symptoms severe 60 mm25-50%> 60 mm (may be decreased)>60%Often decreasedLeft ventricular wall thicknessDecreasedNormal or increasedMarkedly increasedAtrial sizeIncreasedIncreased; may be massiveIncreased; related to abnormalValvularregurgitationRelated to annular dilation; mitral appears earlier, during decompensation; tricuspid regurgitation in late stagesRelated to endocardial involvement; frequent mitral and tricuspid regurgitation, rarely severeRelated to valve-septum interaction; mitral regurgitationCommon first symptomsExertional intoleranceExertional Intolerance, fluid retention earlyExertional intolerance; may have chest painCongestivesymptoms"Left before right, except right prominent in young adultsRight often dominatesLeft-sided congestion may develop lateArrhythmiaVentricular tachyarrhythmia; conduction block in Chagas' disease, and some families, j Atrial fibrillation.Ventricular uncommon except in sarcoidosis conduction block in sarcoidosis and amyloidosis. Atrial fibrillation.Ventriculartachyarrhythmias; atrial fibrillation
Dilated
Restricted
Hypertrophic
Infiltrative
Cardiomyopathy & Pericarditis