Diagnostic accuracy of P-wave dispersion in prediction of maintenance of sinus rhythm after external cardioversion of atrial fibrillation.

OBJECTIVE P-wave dispersion (PWD) is an electrocardiographic measurement, which reflects a disparity in an atrial conduction. In this study, we aim to demonstrate the diagnostic accuracy of PWD in predicting recurrence of atrial fibrillation (AF) in patients with sinus rhythm restoration after external cardioversion. METHODS This prospective, observational study consists of 26 patients, who underwent external cardioversion for non-valvular persistent AF and successfully cardioverted to sinus rhythm (13 men, mean age 58.1 ± 11 years). Twelve-lead surface electrocardiogram of each patient was recorded immediately after the external cardioversion process to measure the P-wave duration. Recurrent AF was assessed for each patient during the 12-month follow-up after restoring the sinus rhythm. Patients were divided into the 2 groups with respect to the AF recurrence (recurrent AF group, (n=19), and sinus rhythm group, (n=7)) and variables that can affect AF development were compared between the two groups. Stepwise logistic regression analysis was used to identify the independent predictors of AF recurrence and ROC curve analysis was performed to determine the cut-off value of independent factors. RESULTS The two groups have similar demographic, clinical and echocardiographic features. Patients with recurrent AF had significantly higher PWD than those who continued to have a sinus rhythm (80 ± 21 msec vs 53 ± 11 msec, p=0.001, respectively). There is a positive correlation observed between the increase in PWD and the risk of AF recurrence (r=0.643; p=0.001). In logistic regression analysis, PWD was found to be an independent predictor of AF recurrence (OR 1.192 (95% CI 1.032-1.375), p= 0.013). Receiver operating characteristic analysis revealed that the best cut-off value of PWD for maintenance of sinus rhythm was 58 msec (sensitivity: 86%, specificity: 95%, AUC=0.917, 95% CI=0.785-1.05, p=0.001). CONCLUSION This study suggests that PWD analysis after successful external cardioversion has diagnostic accuracy to predict the recurrence of AF.