Case Report: Mavacamten in mid-ventricular and apical hypertrophic cardiomyopathy-a case of targeted therapy beyond left ventricular outflow tract obstruction.

Background: Mavacamten targets cardiac myosin ATPase, reducing the formation of actin-myosin cross-bridges, which alleviates excessive myocardial contraction and improves diastolic function. It has been approved for patients with hypertrophic cardiomyopathy symptomatic for left ventricular outflow tract obstruction. Nevertheless, data on the use of mavacamten in patients with mid-ventricular obstruction and apical hypertrophic cardiomyopathy are limited. Case summary: This patient is a 56-year-old female presenting with chest pain and unexplained syncope, along with mid-ventricular obstruction and apical hypertrophic cardiomyopathy. Echocardiography showed a mid-ventricular peak gradient of 115 mmHg. Her symptoms were relieved after treatment with mavacamten, and at the 32-week follow-up after treatment, the mid-left ventricular cavity peak pressure gradient was reduced to 34 mmHg. Significance: In this case, mavacamten improves mid-ventricular obstruction and alleviates symptoms simultaneously. The symptomatic improvement achieved by mavacamten treatment is not limited to hypertrophic cardiomyopathy complicated with left ventricular outflow tract obstruction; it is also effective for a specific type of hypertrophic cardiomyopathy, namely mid-left ventricular obstruction.