Introduction
Atrial fibrillation (AF), the most frequently encountered cardiac arrhythmia,1 is associated with high mortality and morbidity, mainly due to thromboembolic complications and heart failure. In recent times, catheter ablation (CA) has been found to be effective for treating AF.2,3 However, AF recurs after CA in 10–30% of patients,4.5 and few reports have focused on the use of electrocardiography (ECG) for predicting AF recurrence after CA.
Signal-averaged electrocardiography (SAECG) is a technique used for recording microvolt-potentials from the body surface. QRS-SAECG is commonly performed, and positive QRS-SAECG findings have been found to be associated with fatal ventricular arrhythmias and sudden cardiac death.6 In contrast, robust evidence on the use of P-wave SAECG (P-SAECG) is lacking. Previous reports have demonstrated that P-SAECG findings of atrial late potentials (ALP) could be indicative of atrial fibrosis, an arrhythmogenic substrate, in patients with AF. Therefore, P-SAECG could be useful for identifying patients at risk of developing new-onset AF7,8 and those in whom conversion from paroxysmal to chronic AF is likely.9
We hypothesized that pre-recorded ALP would differ between patients with and without AF recurrence after CA, and positive ALP would be associated with AF recurrence.