Prognostic impact of mitral regurgitation in elderly patients with atrial fibrillation: results from the CABANA trial

Background Mitral regurgitation (MR) is the most common valvular heart disease and the most common comorbidities of atrial fibrillation (AF), which is prevalent with age. Nonetheless, the prognosis of MR in elderly patients with AF has not been fully elucidated. Aim This study is a post hoc analysis of the CABANA (Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation) trial. Methods Patients were classified into two groups: those with moderate or severe MR (msMR) and those with no or mild MR (nmMR). The primary endpoint was a composite of death, disabling stroke, serious bleeding or cardiac arrest. The secondary endpoints included all-cause mortality and the composite of all-cause mortality and heart failure hospitalisation. Quality of life was assessed at baseline, 3 and 12 months, and annually up to 60 months. Results Overall, 1368 participants were included in the final analysis (mean age: 65.6±8.2; female 61.3%), including 135 patients with msMR and 1233 with nmMR. The primary endpoint occurred in 7.2% of patients with nmMR versus 14.1% with msMR (HR 1.97, 95% CI 1.20 to 3.25; p=0.008). The secondary endpoint rates for nmMR versus msMR, respectively, were 4.7% vs 8.8% for all-cause mortality (HR 1.73, 95% CI 0.92 to 3.25; p=0.089) and 10.8% vs 15.5% for the composite of death and heart failure hospitalisation (HR 1.25, 95% CI 0.78 to 1.99; p=0.357). Conclusions Among elderly patients with AF, msMR is associated with an increased risk of the primary composite endpoint of death, disabling stroke, serious bleeding or cardiac arrest. Trial registration number NCT00911508 .