'CLOSE'-Guided Pulmonary Vein Isolation and Changes in Local Bipolar and Unipolar Atrial Electrograms: Observations from the EP Lab.

Background: 'CLOSE'-guided pulmonary vein isolation (PVI) is a point-by-point, contact force (CF)-guided radiofrequency (RF) approach aiming to enclose the PVs with contiguous RF lesions by targeting strict criteria for interlesion distance and ablation index (AI). We characterized real-time changes in bipolar (B-EGMs) and unipolar electrograms (U-EGMs) during AI-targeted RF delivery.

Methods: EGM changes during 56 RF applications in 7 patients with paroxysmal atrial fibrillation (AF) undergoing 'CLOSE'-guided PVI were studied.