Background/Introduction: A standardized and optimized approach to pulmonary vein isolation (PVI) using contiguous lesions and tailored Ablation Index (AI) targets has been associated with safe procedure workflow and high success rates in recent single-center reports.
Purpose: The reproducibility of the workflow and its impact on procedural efficiency, safety, and effectiveness of paroxysmal atrial fibrillation (PAF) ablation is being evaluated in the multicenter VISTAX study.
Methods: The study completed enrollment in January 2018 with 340 patients (pts) included at 17 European centers. Interim analysis on the first 157 pts forms the basis of this abstract. All pts (age, 62.2±10.4 years; 60% male; median left atrial diameter, 39 mm) underwent complete encircling of PVs using a contact force sensing catheter targeting an inter-lesion distance (ILD) ≤6 mm with target AI of 550 on the anterior wall and 400 on the posterior wall (or lower, per operator's discretion, if esophageal temperature rise). All pts underwent adenosine testing 30 minutes post PVI to unmask latent conduction. Each map created with a 3D mapping system was then exported to a core reference lab where adherence to the AI protocol was adjudicated.
Results: General anesthesia was used in 152 (96.8%) pts and steerable sheaths in 44 (28%). First-pass isolation was achieved in 139 (88.5%) pts, and adenosine-proof isolation at 30 minutes was seen in 130 (82.8%) pts. Median procedure (including 30 min waiting time) and fluoroscopy times were 150 minutes (133–180) and 4.8 minutes (2.9–8.0), respectively. Overall, 133/155 (85.8%) procedures were adjudicated to meet the criteria for ILD and therapeutic AI lesions.
Conclusion(s): Standardized AI guided PVI is reproducible across different centers, is associated with short and predictable procedure and fluoroscopy time, and high rates of first-pass isolation and acutely durable PV isolation. Detailed procedural data and acute performance and safety for the whole 340-patient cohort will be presented at the congress.