Efficacy of Mavacamten in Patients With Symptomatic Latent Obstructive Hypertrophic Cardiomyopathy

Efficacy of Mavacamten in Patients With Symptomatic Latent Obstructive Hypertrophic Cardiomyopathy: A Randomized Controlled Trial

This study aimed to evaluate the efficacy and safety of Mavacamten compared to no treatment in patients with symptomatic latent obstructive hypertrophic cardiomyopathy. The trial was randomized into two groups: Mavacamten group and Non-Mavacamten group. Over the 30-week treatment period, patients underwent a series of assessments at predefined time points, including transthoracic echocardiography, electrocardiogram (ECG), Holter monitoring, NYHA functional classification, Kansas City Cardiomyopathy Questionnaire (KCCQ), and cardiac biomarkers.

Inclusion Criteria:

1. Age ≥18 years.
2. Weight greater than 45 kg.
3. Adequate acoustic windows to allow for accurate transthoracic echocardiograms (TTEs).
4. Diagnosis of latent obstructive hypertrophic cardiomyopathy, in accordance with the current guidelines of the American College of Cardiology Foundation/American Heart Association, European Society of Cardiology, and Chinese Society of Cardiology.
5. Left ventricular ejection fraction (LVEF) ≥55% at rest, confirmed by the echocardiography core laboratory.
6. New York Heart Association (NYHA) Class II or III symptoms at the time of screening.
7. Resting oxygen saturation ≥90% at the time of screening.

Exclusion Criteria:

1. Any acute or severe comorbidities (e.g., severe infections or hematological, renal, metabolic, gastrointestinal, or endocrine dysfunction).
2. Currently using or having used prohibited medications within 14 days prior to screening, such as cytochrome CYP2C19 inhibitors (e.g., omeprazole or esomeprazole) or strong CYP3A4 inhibitors.
3. Life expectancy of less than 1 year.
4. Pregnant or breastfeeding women.
5. History of syncope or sustained ventricular tachyarrhythmia during exercise within the past 6 months.
6. Atrial fibrillation (AF).
7. Patients currently receiving or planning to receive treatment with disopyramide, cibenzoline, ranolazine, or a combination of beta-blockers with verapamil or diltiazem.