Background:
Evidence on mavacamten treatment in elderly patients with obstructive hypertrophic cardiomyopathy (oHCM) remains limited. This study compared longitudinal efficacy and safety in patients aged ≥65 versus <65 years treated at a tertiary German centre.
Methods:
This longitudinal observational cohort study included consecutive oHCM patients initiated on mavacamten. Patients were stratified by age at baseline into elderly (≥65 years) and younger (<65 years) groups. Baseline characteristics, echocardiographic gradients, biomarkers, functional status and exercise capacity were compared between groups. Follow-up was censored at 12 months. Safety analyses used patient-level adverse event indicators to avoid multiple counting of repeated event columns within the same patient.
Results:
The cohort included 165 patients: 105 aged <65 years and 60 aged ≥65 years. Elderly patients were more often female (62% vs 39%, p=0.009), had lower BMI (27.0±4.5 vs 29.6±6.1 kg/m², p=0.002), and showed higher baseline resting LVOT gradients (40.0 [22.0; 65.5] vs 30.0 [15.0; 50.0] mmHg, p=0.035), NT-proBNP (1109 [677; 1696] vs 676 [315; 1507] ng/L, p=0.008) and high-sensitivity troponin T (14.4 [10.4; 21.0] vs 12.0 [9.1; 17.4] ng/L, p=0.032). Baseline maximal LVOT gradients were comparable (85.0 [65.0; 111.2] vs 80.5 [55.0; 109.2] mmHg, p=0.149), as were NYHA class and LVEF. Both groups demonstrated marked and sustained LVOT gradient reductions during treatment. Maximal LVOT gradients decreased by 12 months to 9.5 [0.0; 12.5] mmHg in elderly patients and 8.0 [0.0; 17.8] mmHg in younger patients (p=0.941). Resting LVOT gradients decreased to 5.0 [0.0; 7.2] versus 4.5 [0.0; 8.8] mmHg (p=0.842), and Valsalva gradients to 8.0 [0.0; 12.5] versus 7.5 [0.0; 16.5] mmHg (p=0.711), respectively. NYHA class improved similarly, reaching in median 2.0 [1.0; 2.0] in elderly and 1.5 [1.0; 2.0] in younger patients at 12 months (p=0.492). LVEF remained preserved without significant between-group differences throughout follow-up. NT-proBNP remained numerically higher in elderly patients during follow-up, but the between-group difference was no longer significant at 12 months (309 [141; 690] vs 185 [113; 341] ng/L, p=0.145). Any hospitalization (8.6% vs 11%, p=0.789), heart failure hospitalization (1.7% vs 2.9%, p=1.000), arrhythmias and syncope did not differ significantly. LVEF decrease was numerically more frequent in elderly patients (8.6% vs 2.9%, p=0.136). Overall mavacamten discontinuation occurred more often in elderly patients, also due to subjective intolerance (14% vs 3.8%; OR 3.96, 95% CI 1.00-18.86; p=0.028). No strokes, deaths, VT/VF, heart transplantation or LVAD implantation were observed.
Conclusion:
In this real-world tertiary-centre cohort, mavacamten produced substantial and sustained reductions in LVOT obstruction with comparable symptomatic improvement in elderly and younger oHCM patients through 12 months. Overall adverse event rates were not significantly higher in elderly patients, although treatment discontinuation was more frequent, supporting careful monitoring and individualized dose management in this age group.
