see also: [[Syncope ECG patterns#Hypertrophic Cardiomyopathy|HOCM ECG]] > [!Key Points] # types - Dilated - restrictive - hypertrophic # Dilated cardiomyopathy - most common - low ejection fraction ; heart dilates to compensate ## causes - HTN - ischemia - genetics - viral myocarditis - EtOH - post-partum (?autoimmune) ## treatment - remove underling cause - treat CHF and arrhythmias - anticoagulation - transplant in severe non-reversible causes - pharm for different subgroups (ACE-I, BB, diuretics, nitrites) # Restrictive cardiomyopathy - fibrosis or infiltration of heart muscle - stiff, inflexible muscle and chambers - normal or near-normal ejection fraction - **problem with filling** > results in heart failure with "normal sized" heart ## causes - amyloidosis - sarcoidosis - radiation (fibrosis) - TB (pericardial disease) # Hypertrophic cardiomyopathy - heart muscle that is too big or asymmetric - usually left ventricle - classic: septum and inferior to aorta are hypertophied - **severe symptoms on exercise** ## several types all essentially the same: - idiopathic hypertrophic subartic stenosis - asymmetric septal hypertrophy - **hypertrophic obstructive cardiomyopathy** (HOCM) - essentially **septal hypertrophy** - Hypertrophic obstructive cardiomyopathy = classic murmur at left lower sternal border (murmur increases with Valsalva, decreases with squatting/fist-clenching) - Hypertrophic obstructive cardiomyopathy workup = ECHO, ECG (LVH and needle-like Q waves) ## symptoms - SOB - atypical chest pain - fatigue - **exercise-induced syncope** - classic murmur lower left sternal edge: - **increases** with valsalva (less blood in heart) - **decreases** with increased peripheral vascular resistance (squatting) ## diagnosis - ECHO - CXR usually NAD - [[Syncope ECG patterns#Hypertrophic Cardiomyopathy ECG]] - ## treatment - **Beta-blockers** are the mainstay medical treatment of hypertrophic obstructive cardiomyopathy - avoid exertion - avoid positive ionotropes - AICD for ventricular arrhythmia - sirgical ablation of septum hypertrophy