Detection of patients with hypertrophic cardiomyopathy at risk for paroxysmal atrial fibrillation during sinus rhythm by P-wave dispersion

Background: Paroxysmal atrial fibrillation (PAF) in hypertrophic cardiomyopathy (HCM) is associated with poor prognosis. Previous studies have shown good correlation between P-wave dispersion (Pd) and occurrence of PAF. However, Pd in patients with HCM for predicting PAF has not been studied. Hypothesis: The aim of the study was to determine whether Pd could identify patients with HCM who are likely to suffer from PAF. Methods: Twenty-two patients with HCM with a history of PAF (Group 1) and 26 patients with HCM without a history of PAF (Group 2) were studied. Maximum (Pmax) and minimum (Pmin) P-wave durations, as well as P-wave dispersion (Pd = Pmax - Pmin) were calculated from 12-lead surface electrocardiograms (ECG). Results: P-wave dispersion was significantly different between the groups (Group 1: 55 ± 6 ms vs. Group 2: 37 ± 8 ms; p < 0.001), while Pmax (Group 1: 134 ± 11 ms vs. Group 2: 128 ± 13 ms; p = 0.06) and Pmin (Group 1: 78 ± 9 ms vs. Group 2: 81 ± 7 ms; p = 0.07) was not significantly different. Patients with a history of PAF had higher left atrial diameter than the patients without PAF (Group 1: 52 ± 8 mm vs. Group 2:48 ± 10 mm; p = 0.02). A cut-off value of 46 ms for Pd had a sensitivity of 76% and a specificity of 82% in discriminating between patients with and without PAF. Conclusion: This study suggests that P-wave dispersion could identify patients with HCM who are likely to develop PAF.