Pulmonary Vein Antrum Isolation (PVAI) Plus Scar Homogenization and Non-PV Triggers Ensure Long-term Recurrence-free Survival in Non-paroxysmal Atrial Fibrillation

Overview

This study aims to examine the long-term success rate of catheter ablation in non-paroxysmal atrial fibrillation patients using different ablation strategies such as : (i) pulmonary vein antrum isolation (PVAI) + isolation of left atrial posterior wall, (ii) PVAI plus scar homogenization, (iii) PVAI plus isolation of posterior wall plus ablation of non-PV triggers \[ PVAI: Pulmonary Vein Antrum Isolation Non-PV triggers: Triggers arising from sites other than pulmonary veins\]

Back ground: Pulmonary vein antrum isolation (PVAI) as a lone procedure, is known to have limited success rate in terms of long-term recurrence-free survival in non-paroxysmal atrial fibrillation (NPAF) and additional ablations isolating extra-PV triggers seem to improve the outcome (1). The extra-PV triggers include triggers from other sites such as left atrial posterior wall, superior vena cava, interatrial septum, crista terminalis, left atrial appendage and coronary sinus (1, 2). These are known to be independent predictors of late AF recurrence following catheter ablation (3, 4, and 5). Earlier studies have demonstrated better ablation outcome in NPAF when non-PV triggers sites were isolated along with PVAI (5, 6). Moreover, Verma et al had reported high (57%) recurrence rate post-index procedure in AF patients with pre-existent scar (7). However, published data are conflicting regarding the benefits of additional substrate guided ablation (scar homogenization) compared to conventional PVAI alone strategy (8). Also, limited data is available showing a comparison of the lasting efficacy of the above three procedures when used in different combinations. Hypothesis: The combined ablation strategy including PVAI, scar homogenization and ablation of extra-PV triggers has the highest likelihood of maintaining long-term sinus rhythm in patients with NPAF.