Atrial fibrillation in dilated cardiomyopathy: Outcome prediction from an observational registry

Little is known about the role of different types of atrial fibrillation (AF) in dilated cardiomyopathy (DCM). We investigated the epidemiological and prognostic impact of different types of AF in DCM during long-term follow-up. We evaluated consecutive DCM patients enrolled in the Trieste Muscle Heart Disease Registry. Uni- and multivariable, extended Kaplan-Meier and propensity score-matching analyses were performed for a composite outcome including death/heart transplantation/ventricular-assist device implantation. Out of 1181 DCM patients (71% males, age 49 ± 15 years, left ventricular ejection fraction 33 ± 11%), 46 (3.9%) had baseline permanent AF (permAF), while 66 (5.6%) had a history of paroxysmal/persistent AF. Compared with sinus rhythm (SR) patients, permAF patients were older (48 ± 15 vs. 61 ± 11 respectively, p = 0.001), were more frequently in NYHA class III-IV (18% vs. 30%, p = 0.002) and had larger left atrium diameter (40 ± 8 vs. 50 ± 10 mm, respectively). Paroxysmal/persistent AF patients had intermediate characteristics between permAF and SR. During a median follow-up of 135 (75–210) months, 63 patients developed permAF (0.45 new cases/100patients/year). At multivariable analysis, permAF as a time-dependent variable was an independent outcome predictor (HR 2.45; 95% C.I. 2.61–3.63, p