HOCM: Management

Key points

• Hypertrophic cardiomyopathy: autosomal dominant, caused by sarcomere protein gene mutations; prevalence around 1 in 500.
• Symptomatic obstructive HCM: a beta-blocker is first-line (verapamil if beta-blockers not tolerated); disopyramide may be added for refractory outflow obstruction. If symptoms persist despite optimal drugs, the myosin inhibitor MAVACAMTEN (ESC 2023) is an option, alongside or before septal reduction therapy (surgical myectomy or alcohol septal ablation).
• Sudden cardiac death risk is estimated formally with the ESC HCM Risk-SCD calculator (age, maximal wall thickness, left atrial diameter, LV outflow gradient, family history of SCD, non-sustained VT, unexplained syncope). In the low-to-moderate risk group, additional modifiers include extensive LGE (over 15%) on CMR, LVEF under 50%, and an LV apical aneurysm. An ICD is offered on estimated risk, not on any single feature.
• Amiodarone is not the answer to non-sustained VT in HCM — the decision is whether an ICD is indicated.
• AVOID: nitrates, ACE inhibitors, inotropes, and any agent that reduces preload or afterload (they worsen outflow obstruction); use diuretics with caution.
• Atrial fibrillation is poorly tolerated and carries a high thromboembolic risk — anticoagulate regardless of CHA2DS2-VASc score. Offer first-degree relative screening and genetic counselling. Endocarditis antibiotic prophylaxis is not recommended routinely (NICE CG64, amended 2016).

Decision points in this pathway

• Symptomatic (dyspnoea, chest pain, presyncope) with outflow tract obstruction?
• Estimated 5-year sudden death risk high enough to warrant an ICD?

The full step-by-step algorithm, including what to do at each branch, opens in the app for approved members.