Abnormal P-wave characteristics were reportedly associated with left ventricular interstitial fibrosis as defined by cardiac magnetic resonance images. The objective of this study is to investigate the utility of P-wave characteristics to predict atrial fibrillation (AF) recurrence and the recovery of left ventricular systolic dysfunction (LVSD) after catheter ablation (CA) for AF. Two hundred and five AF patients (109 paroxysmal and 96 persistent) who underwent CA were enrolled. We measured maximum P-wave duration (max PWD) and P-wave terminal force in lead V1 (PTFV1) calculated as a product of P-wave terminal amplitude (PTaV1) and duration (PTdV1) in lead V1 during sinus rhythm. AF recurrence was noted in 50 patients at 12 months after CA. Patients with AF recurrence had a higher prevalence of persistent AF, a larger left atrial volume, and a longer max PWD than those without. We divided the patients into 2 groups: 156 patients with left ventricular ejection fraction (LVEF) > 45% and 49 patients with LVEF ≤ 45% (Low-EF group). In Low-EF group, tachycardia-induced cardiomyopathy (TIC) was defined as improvement in LVEF ≥ 15% or LVEF ≥ 50% at 5 months after CA. TIC and non-TIC groups consisted of 37 and 12 patients, respectively. Max PWD, PTFV1, PTdV1, and PTaV1 were significantly greater in non-TIC-group than in TIC-group. PTFV1 had the highest diagnostic accuracy to discriminate between TIC and no-TIC-groups; cut-off value for PTFV1 was determined as 56.7 mV ms (area under the ROC curve = 0.80; 75% sensitivity; and 76% specificity). Max PWD was a useful predictor of AF recurrence and the complete recovery of LVSD after CA. PTFV1 had the highest diagnostic accuracy to discriminate between TIC and no-TIC-groups.
