Hypertrophic cardiomyopathy is an autosomal dominant cardiac condition characterized by marked left ventricular hypertrophy with a non-dilated ventricular cavity, and in around 20% of patients left ventricular outflow obstruction.
It is the commonest genetic cardiac disease (incidence 1 in 500) and the commonest cause of sudden cardiac death in the young.
Presentation may be:
- Sudden death
- Syncope
- Shortness of breath
- Angina
- Palpitations
Clinical findings may include:
- Ejection systolic murmur
- If obstruction is present this murmur may be increased by valsalva
- Prominent A wave in JVP
- Bifid pulse (obstructive only)
- ? MR
- ? split S2
Investigation
- Echocardiography
- Hypertrophied and non-dilated left ventricle
- ECG
- ? LVH
- ? AF
- ? Q waves
- ? TWI
Prognosis include:
- Sudden death (classically stated at 6% per year but now believed to be lower – around 1%)
- Atrial fibrillation (20-25%)
- Heart failure symptoms
- No symptoms
Risk factors for sudden death
- Family history of sudden death
- Unexplained syncope
- Massive LV hypertrophy (thickness >30mm)
- Non-sustained VT on ambulatory ECG
- Hypotensive on exercise
Management – depends on severity and symptoms
- Medical
- Beta blockers
- Verapamil
- Surgery
- Percutaneous alcohol septal ablation
- Dual chamber pacing
- ICD
- Avoid nitrates/ACE-i/digoxin in outflow tract obstruction
References
Maron, B. et al. American College of Cardiology/European Society of Cardiology Clinical expert consensus document on hypertrophic cardiomyopathy. European Heart Journal. 2003; 24: 1965-1991.Maron, B. Contemporary insights and strategies for risk stratification and prevention of sudden death in hypertrophic cardiomyopathy. Circulation. 2010; 121(3): 45-456.
