Multiple epicardial connections during extensive pulmonary vein isolation.

A 76-year-old male underwent a pulmonary vein isolation (PVI) of atrial fibrillation. The first-pass encirclement did not isolate the left superior PV (LSPV). High-resolution activation mapping during LSPV pacing identified the earliest activation site (EAS) on the left atrial (LA) roof outside the PVI line. A radiofrequency application on the roof isolated the LSPV. Thereafter, an LSPV reconnection occurred. Second activation mapping during LSPV pacing identified the EAS at the bottom of the ridge outside the PVI line. Radiofrequency applications targeting the EAS eliminated the LSPV reconnection. The multiple residual connections may be associated with spared epicardial PV-LA connections.