Abstract
BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a myocardial disorder characterized by hypertrophy of the left ventricle that can lead to significant symptoms, particularly with exercise. For patients with HCM who demonstrate obstructive physiology, the first-in-class targeted cardiac specific myosin inhibitor, mavacamten, has been found to reduce the degree of obstruction as well as symptoms. CASE SUMMARY: We present a patient with symptomatic HCM who had no left ventricular outflow tract obstruction (LVOTO) at rest but demonstrated obstruction on treadmill stress echocardiography. She had symptomatic improvement after treatment with mavacamten. DISCUSSION: Patients with symptomatic HCM who do not demonstrate elevated resting gradients may benefit from evaluation of exercise-induced gradients to diagnose obstructive HCM and guide initiation of targeted therapy with mavacamten. TAKE HOME MESSAGE: Mavacamten may be safe and effective in patients who demonstrate LVOTO only upon provocation with exercise.