Heart failure & cardiomyopathiesCohort study
New and recurrent atrial fibrillation in patients with obstructive hypertrophic cardiomyopathy receiving mavacamten
- retrospective observational study
Authors' conclusion
Although patients with oHCM had a high baseline risk of AF, mavacamten treatment was associated with an increased risk of AF development beyond that predicted by the HCM-AF score.
Study context
- Population
- Patients with obstructive hypertrophic cardiomyopathy (oHCM) undergoing mavacamten treatment at the Johns Hopkins Hypertrophic Cardiomyopathy (HCM) Centerincluding 30 (18.8%) with a diagnosis of atrial fibrillation (AF) before mavacamten treatment
- Participants
- 160 patients
- Exposure
- without a previous AF diagnosis vs previous AF diagnosis
- previous AF diagnosisn = 30
Main finding
As reported in the abstract
New AF in those without a previous AF diagnosis · median of 1.4 years of mavacamten treatment (interquartile range 0.6-2.3)
without a previous AF diagnosis
6.4%/y
rate
Observational data: associations, not effects.
Further findings
- AF recurrence in patients with a previous AF diagnosis · during mavacamten treatment
- 19.3%/y · rate
Observed vs HCM-AF predicted risk of symptomatic AF · 2-year
- observed 2-year risk
- 8.2%
- HCM-AF risk prediction
- 6.9%
- observed risk modestly exceeded HCM-AF risk predictions
New, clinically significant AF associated with mavacamten
- hazard ratio (mavacamten, increased risk)
- 3.0; P = .01
- time-dependent multivariable Cox regression
Baseline characteristics and HCM-AF score · mavacamten initiation
- mean age
- 62 years
- female
- 58%
- Median HCM-AF score
- 23
HCM-AF score discrimination
- concordance statistic
- 0.78
Original publication
New and recurrent atrial fibrillation in patients with obstructive hypertrophic cardiomyopathy receiving mavacamten. Heart Rhythm. Published 23 April 2026. doi:10.1016/j.hrthm.2026.04.033
Summarised from the published abstract; every number is checked against it