Obesity is associated with long-term outcome of catheter ablation of atrial fibrillation in patients with dilated cardiomyopathy.

Background: Patients with atrial fibrillation (AF) and dilated cardiomyopathy (DCM) often exhibit cardiac dysfunction and a poor prognosis. However, the specific reasons are unclear. This study aimed to describe the impact of obesity in patients with AF and DCM.

Methods: Seventy-four consecutive patients with AF and DCM were enrolled and classified by body mass index. We measured primary endpoints, including cardiac death, recurrent AF, recurrent atrial tachyarrhythmia and stroke, as well as secondary endpoints.

Results: In multivariate analysis, compared to the normal-weight group, the overweight and obese groups had greater incidences of recurrent AF (0.0 vs 30.3 vs 40.0%, respectively, log-rank p = 0.048) and rehospitalisation (9.1 vs 36.4 vs 45.0%, respectively, log-rank p = 0.035). Compared to the normal-weight group, five-year outcomes for primary endpoints were inferior in the overweight and obese groups (18.2 vs 30.3 vs 50.0%, respectively, log-rank p = 0.042). Overweight patients exhibited more benefit in recovery of left ventricular ejection fraction after ablation (from 39.1 to 50.0%, p = 0.005) than the normal-weight group (from 43.1 to 52.3%, p = 0.199) and obese group (from 44.9 to 51.2%, p = 0.216).

Conclusion: Patients with AF and DCM with overweight or obesity exhibited worse long-term outcomes in recurrent AF than normal-weight patients. However, overweight patients showed the most benefit in cardiac function after ablation.