RESUMO
BACKGROUND: Atrial fibrillation (AF) is a common problem in pacemaker patients. We conducted a prospective observational study in patients paced for bradycardia with associated paroxysmal or persistent AF, to determine whether P-wave duration may stratify patients at higher risk for AF recurrences and AF-related hospitalizations. The patients were evaluated for the prevalence, cause, and predictors of hospitalization. METHODS: We studied 660 consecutive patients (50% male, 72 +/- 9 years) who received a dual-chamber pacemaker. Median value of baseline P-wave duration was equal to 100 ms (25%-75% quartile range equal to 80-120 ms). We used this cut-off to divide the patients into group A (P < or = 100 ms), composed of 385 (58.3%) patients, and group B (P>100 ms), composed of 275 (41.7%) patients. RESULTS: In a median follow-up of 19 months, 173 patients were hospitalized for all causes, 130 for cardiovascular causes, and 85 for AF-related hospitalizations. Multivariate logistic analysis showed that P-wave duration >100 ms identified patients at higher risk (OR = 1.6, 95% confidence interval (1.1-2.8), P = 0.044) for AF-related hospitalizations. Patients in group B (P > 100 ms) more frequently suffered AF-related hospitalizations (16.4% vs 10.4%, P = 0.02) and underwent more frequent cardioversions (14.5% vs 9.1%, P = 0.029) compared with group A (P < or = 100 ms). CONCLUSIONS: P-wave duration may define the risk of persistent AF requiring cardioversion or AF-related hospitalization in patients with a pacemaker for bradycardia with associated paroxysmal or persistent AF.