A 35-year-old woman presents with dyspnoea, exertional syncope, and loud S4. Echocardiography shows asymmetric hypertrophy of the interventricular septum (26 mm), systolic anterior motion of the mitral valve, and outflow tract gradient of 65 mmHg at rest. She is on bisoprolol 10 mg. What is the next appropriate intervention for refractory obstructive HCM?
- A Surgical septal myectomy
- B Alcohol septal ablation
- C Dual-chamber pacing (DDD pacing)
- D Mavacamten (cardiac myosin inhibitor) ✓
Explanation
Mavacamten is a first-in-class selective cardiac myosin ATPase inhibitor that reduces hypercontractility in obstructive HCM. The EXPLORER-HCM trial demonstrated significant improvement in LVOT gradient, symptoms, and exercise capacity. Mavacamten (FDA approved 2022) is now indicated per ACC/AHA 2024 HCM guidelines for symptomatic obstructive HCM (resting LVOT gradient ≥55 mmHg) inadequately controlled on beta-blockers, as a non-invasive alternative before proceeding to septal reduction therapy. Surgical myectomy and alcohol septal ablation remain options for drug-refractory cases.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.