Effect of Mavacamten on Echocardiographic Features in Chinese Patients with Obstructive Hypertrophic Cardiomyopathy: Results from the EXPLORER-CN Study

作者：Zhuang Tian, Xiaoyan Li, Liwen Li, Qing Zhang, Jianan Wang, Yunqi Shi, Daoquan Peng, Ping Yang, Wei Ma, Fang Wang, Wei Jin, Xiang Cheng, Yu-Mao Chen, Yue Zhong, Yu Chen Barrett, Jing Zheng, Shuyang Zhang · 发表于：Cardiology and Therapy · 年份：2025 · DOI：10.1007/s40119-025-00409-5 · 被引用次数：8 · 研究领域：Cardiomyopathy and Myosin Studies、Cardiovascular Function and Risk Factors、Heart Failure Treatment and Management

Mavacamten, a cardiac myosin inhibitor, has demonstrated positive outcomes in left ventricular outflow tract (LVOT) gradient reduction and improvements of symptoms and function in Chinese patients with symptomatic obstructive hypertrophic cardiomyopathy (HCM) in EXPLORER-CN. This exploratory analysis aimed to evaluate the effect of mavacamten on echocardiographic measures of cardiac structure and function and its relationship with other clinical biomarkers. Key echocardiographic parameters acquired over 30 weeks from 81 patients ( n = 54 on mavacamten and n = 27 on placebo) were assessed in a central laboratory. At 30 weeks, greater improvements in measures of diastolic function were observed with mavacamten versus placebo, including lateral E / e ′ (least-squares mean [LSM] change from baseline [CFB] − 5.1 vs. 0.6; between-group LSM difference − 5.7; 95% confidence interval [CI] − 7.6 to − 3.7), septal E / e ′ (LSM CFB − 6.0 vs. − 0.3; between-group LSM difference − 5.7; 95% CI − 7.8 to − 3.7), and left atrial volume index (LAVI) (LSM CFB − 11.7 vs. − 3.5 ml/m 2 ; between-group LSM difference − 8.2; 95% CI − 12.0 to − 4.4) (nominal p < 0.001 for all). Twelve patients (23.1%) treated with mavacamten had complete resolution of mitral valve systolic anterior motion (SAM) versus two patients (7.4%) receiving placebo. Among mavacamten-treated patients, reductions in resting and Valsalva LVOT gradients, left ventricular (LV) mass index, LAVI, and lateral and septal E / e ′ were as...