Abstract Background and Aims Atrial fibrillation (AF) commonly coexists with hypertrophic obstructive cardiomyopathy (HOCM) and is associated with increased risks of stroke and mortality. While catheter ablation (CA) is effective in AF, outcomes in patients with HOCM remain underreported. We sought to evaluate the association between CA and long-term outcomes in patients with paroxysmal AF (PAF) and HOCM. Methods Using the TriNetX Research Network, we identified adults (≥18 years) diagnosed with HOCM and PAF between 2015 and 2021. Patients were stratified into CA vs. non-CA groups. Propensity score matching (1:1) was used to adjust for differences in demographics, comorbidities, and medications. The primary outcome was all-cause mortality and ischemic stroke at 3 years; secondary outcomes included cardioversion and new-onset heart failure. Kaplan-Meier analysis and Cox proportional hazards regression were used to estimate adjusted hazard ratios (HRs). Results Among 8,593 patients with HOCM and PAF, 1,018 (11.8%) underwent CA. Post-PSM, 966 patients were matched per group. All-cause mortality was markedly reduced in the CA group (4.9% vs. 13.7%, HR: 0.35, 95% CI: 0.25–0.49, p 0.0001). Ischemic stroke rates were significantly lower in the CA group (6.4% vs. 9.7%, HR: 0.63, 95% CI: 0.46–0.87, p 0.01), including among patients without prior stroke (de novo stroke: 3.7% vs. 5.7%, HR: 0.63, 95% CI: 0.40–0.98, p 0.05). Cardioversion was significantly higher following CA (30.1% vs. 10.1%, HR: 3.2, 95% CI: 2.5–4.0, p 0.0001). There was no significant difference in new-onset heart failure between the CA and non-CA groups (69.1% vs. 72.0%; HR: 1.08, 95% CI: 0.84–1.40, p = 0.53). Conclusions In patients with HOCM and PAF, CA was associated with significantly lower risks of ischemic stroke and all-cause mortality.
Dulal et al. (2025) studied this question.