Cardiomyopathy Flashcards
What is cardiomyopathy?
Cardiomyopathy is a myocardial disorder in which the heart muscle is structurally and functionally abnormal, in the absence of coronary artery disease, hypertension, valvular disease and congenital heart disease sufficient to cause the observed abnormality
what is the most common form of cardiomyopathy?
Dilated cardiomyopathy accounting for 90% of cases
what inherited condition predisposes you to dilated cardiomyopathy?
duchenne muscular dystrophy
describe the pathophysiology of dilated cardiomyopathy
dilated heart leads to predominantly systolic dysfunction
all four chambers of the heart are dilated but the left ventricle more so than the right ventricle
what are the features of dilated cardiomyopathy?
classical findings of heart failure
systolic mummy due to stretching of the valves leading to mitral and tricuspid regurgitation
HS3
balloon appearance of the heart on CXR
what is Takotsubo cardiomyopathy?
type of non ischaemic cardiomyopathy associated with a transient apical ballooning of the myocardium.
why does the apical ballooning occur in takotsubo cardiomyopathy?
due to hyperkinesis of the mid and apical segments with preservation o activity of the basal segments.
the bottom of the heart (the apex) does not contract and therefore appears to balloon out.
what are some features of takotsubo cardiomyopathy?
chest ain, features of HF, ST elevation on ECG and normal coronary angiogram
what is the treatment for takotsubo cardiomyopathy?
treatment is supportive and prognosis is good
what is hypertrophic obstructive cardiomyopathy?
an autosomal dominant disorder of muscle tissue caused by defects in the genes encoding contractile proteins.
results in predominantly diastolic dysfunction
left ventricle hypertrophy → decreased compliance → decreased cardiac output
what is the most common cause of sudden death in the young?
hypertrophic obstructive cardiomyopathy
what are the features of hypertrophic obstructive cardiomyopathy?
often asymptomatic
exertional dyspnoea
angina
syncope
typically following exercise
due to subaortic hypertrophy of the ventricular septum, resulting in functional aortic stenosis
sudden death (most commonly due to ventricular arrhythmias),
arrhythmias, heart failure
jerky pulse, large ‘a’ waves, double apex beat
ejection systolic murmur
increases with Valsalva manoeuvre and decreases on squatting
hypertrophic cardiomyopathy may impair mitral valve closure, thus causing regurgitation
what are two conditions associated with hypertrophic obstructive cardiomyopathy?
WPW
Friedrich’s ataxia
what is the treatment of hypertrophic obstructive cardiomyopathy? (ABCDE mnemonic)
Amiodarone Beta-blockers or verapamil for symptoms Cardioverter defibrillator Dual chamber pacemaker Endocarditis prophylaxis*
what tree types of drugs should you avoid in hypertrophic obstructive cardiomyopathy?
nitrates, ACEi and inotropes
