Radiofrequency Ablation in Patients Undergoing Mitral Valve Surgery with or without Giant Left Atria.

PURPOSE

We aimed to compare the efficacy of radiofrequency ablation (RFA) in patients undergoing mitral valve (MV) surgery with or without giant left atria.

METHODS

This retrospective, single-center, cohort study investigated patients who underwent MV surgery and concomitant RFA from 2009 to 2019. Patients were divided into non-giant left atria (diameter ≤65 mm, n = 1543) and giant left atria (diameter >65 mm, n = 241) groups. Five-year freedom from atrial tachyarrhythmia recurrence and thromboembolic event (TE) rates were assessed with death as the competing risk factor with and without propensity-score matching.

RESULTS

Patients with giant left atria had higher mortality (10.8% versus 6.2%, P = 0.008) and readmission rates for heart failure than those without (12.0% versus 6.8%, P = 0.004). Atrial tachyarrhythmia recurrence rates were higher in patients with giant left atria than in those without (49% versus 24% at 5 years, P <0.001), but the cumulative incidence of TEs before (P = 0.944) and after (P = 0.695) propensity-score matching was comparable.

CONCLUSIONS

RFA effectively prevented TEs in patients with giant left atria, despite significant atrial tachyarrhythmia recurrence. Atrial tachyarrhythmia recurrence did not increase the risk of TEs. A lower success rate should be considered when deciding whether to perform surgical ablation in patients with giant left atria.