Mavacamten for Symptomatic Obstructive Hypertrophic Cardiomyopathy During Active Chemotherapy.

BACKGROUND

The role of cardiac myosin inhibitors in patients with obstructive hypertrophic cardiomyopathy (oHCM) and active malignancy remains unexplored.

CASE SUMMARY: A 68-year-old woman with colon cancer presented with worsening dyspnea. Echocardiography showed severe asymmetric septal hypertrophy, systolic anterior motion of the mitral valve, and a peak left ventricular outflow tract gradient of 115 mm Hg. Beta-blocker therapy failed to control symptoms. After multidisciplinary cardio-oncology evaluation, mavacamten therapy was initiated. Within 4 weeks, the patient's left ventricular outflow tract gradient decreased to 10 mm Hg, her NYHA functional class improved to I, and her NT-proBNP levels dropped markedly. Chemotherapy continued without interruption. Nine months later, her oncologic disease progressed, and palliative care was adopted.

DISCUSSION: This case highlights mavacamten as a safe and effective therapy for oHCM in a patient actively receiving chemotherapy. It underscores the potential value of cardiac myosin inhibition in complex comorbid scenarios.

TAKE-HOME MESSAGE: Mavacamten can substantially improve quality of life in oHCM, even in patients with active malignancy.