Abstract 17498: Pulmonary Vein Isolation with a Novel Direct Visualization Ablation Catheter
Background: Pulmonary vein (PV) isolation by series of radiofrequency applications placed outside the PVs has been inconsistently successful to treat AF due to late reconnection of PVs despite initial procedural success. Gaps in the lesion set account for these late recurrences, however, current point by point catheters are unable to create and confirm contiguous lesions. The ability to monitor lesion creation and identify gaps through direct visualization would likely reduce these reconnections.
Methods: We studied a novel direct visualization and ablation catheter (IRISTM, Voyage Medical) that uses saline irrigation to clear the field of view of blood and serve as a virtual RF electrode in 12 canines. Global catheter position was monitored with fluoroscopsy and the Ensite® NavX system. 22 PVs (12 LIPV, 10 RIPV) were targeted for isolation using the study catheter. RF energy was titrated based on visual feedback. Contiguity of the lesion set was verified by direct visualization.
Results: All targeted PVs were isolated with the study catheter as confirmed by entry and exit block. At necropsy, the series of RF applications consistently appeared as a continuous lesion set surrounding the target PV (Figure). Each vein required an average of 39 +/− 9.9 RF applications (25.9 +/− 5.5 sec per application) to ensure electrical isolation. The average power administered was 9.6 +/− 2.2 Watts. There was a 0.3% (2/677) incidence of steam pops during ablation without associated tissue disruption or clinical sequela. There was no evidence of PV narrowing, thrombus, char, collateral tissue damage or other adverse events observed in the study.
Conclusions: PV isolation under direct visualization is safe and effective by creating contiguous lesions around the PVs. Energy titration based on visual feedback can minimize the incidence of steam pops, limit collateral injury, and improve lesion consistency.
- Ablation, radiofrequency
- Arrhythmias, treatment of
- Atrial fibrillation
- Cardiac mapping
- © 2010 by American Heart Association, Inc.