Real-world experience with mavacamten therapy in patients with obstructive hypertrophic cardiomyopathy

Introduction Mavacamten has demonstrated efficacy in reducing left ventricular outflow tract (LVOT) obstruction and improving symptoms in patients with hypertrophic obstructive cardiomyopathy (HOCM). However, real-world data regarding its effectiveness, safety, and echocardiographic impact in routine clinical practice remain limited. Purpose We sought to evaluate the real-world clinical and echocardiographic outcomes of Mavacamten therapy in a tertiary HCM center. Methods We conducted a single-center retrospective analysis of consecutive patients with HOCM treated with Mavacamten between 2019 and 2026. Changes in echocardiographic and clinical parameters including LVOT gradients and New York Heart Association functional class (NYHA), were serially assessed. Adverse events, including death, arrhythmia, and development of heart failure symptoms were documented. Results Of 64 patients who initiated Mavacamten during the study period, 52 were included in the final analysis, 12 were excluded because treatment initiation was too recent to allow adequate follow-up. Mean follow-up duration after treatment initiation was 11 ± 12 months. Mean provoked LVOT gradient decreased from 90 ± 28 mmHg at baseline to 35 ± 31 mmHg at last follow-up (mean reduction 55 ± 45 mmHg, p=<0.001). Improvement of at least one NYHA functional class was observed in 32 patients (61%), with a trend toward greater symptomatic improvement in those with larger LVOT gradient reduction (p=0.099). LVEF remained preserved and did not change significantly (68 ± 5% vs. 66 ± 6%, p=0.384) (Figure 1). The prevalence of SAM decreased from 79% to 47% (p=0.001), accompanied by significant improvement in MR severity (p=0.002). Two patients experienced major adverse events (transient LV systolic dysfunction and new-onset atrial fibrillation), both resolving after Mavacamten discontinuation. Minor adverse effects occurred in eight patients and resolved without intervention. Conclusion In a real-world tertiary-center experience, Mavacamten was associated with substantial reductions in LVOT obstruction, meaningful symptomatic improvement, and favorable remodeling of mitral valve physiology, while maintaining an acceptable safety profile. These findings support the effectiveness and clinical applicability of Mavacamten in routine management of HOCM.