Changes in P-wave polarity and amplitude after circumferential pulmonary vein isolation

Abstract

Objective To observe the influence of circumferential pulmonary vein isolation(CPVI) on P-wave polarity and amplitude and to investigate whether the changes of P-wave are associated with patient outcomes after initial CPVI.Methods Fifty patients with paroxysmal atrial fibrillation(AF) underwent CPVI.For each patient,electrocardiograph(ECG) recordings were taken before and 7 days after ablation.The P-wave polarities and amplitudes were analyzed.Successful CPVI was defined as freedom of symptomatic and asymptomatic AF at the end of two consecutive follow-ups.Results The amplitude of positive P-wave was significantly decreased in the leads of Ⅰ,Ⅱ,Ⅲ,aVF,V5,and V6 after ablation(P0.05).The amplitude of negative P-wave was significantly decreased in the leads of aVR and aVF after ablation(P0.05).The total amplitude of P-wave was significantly decreased in the leads of Ⅰ,Ⅱ,aVR,V5 and V6 after ablation(P0.05).The negative P-wave in the lead of Ⅲ and the positive P-wave in the lead of aVL were increased after ablation.The amplitudes of negative,positive and total P-waves before and after ablation were not significantly different between successful CPVI(n=39) and failure CPVI(n=11) groups.Conclusion CPVI can result in noticeable reduction of P-wave amplitude in several leads of ECG,indicating the reduction of left atrial electric capacity.The changes of P-wave polarity indicate a P-wave vector shift.The reduction degree of P-wave amplitude has no predictive value for the success or failure of CPVI.