Pulmonary Vein Isolation With Ablation Index via Single Transseptal Crossing: Critical Role of Carina Isolation.

AIM: Reconnection of the pulmonary veins (PVs) is the most common reason for the recurrence of atrial fibrillation (AF). The ablation index is a marker of ablation lesion quality that achieves high percentages of first-pass isolation and improved AF ablation results. Most operators use a double transseptal approach with confirmation of PV isolation with a circular mapping catheter. In the present study we aimed to show that an ablation index-guided procedure using a single transseptal approach and ablation catheter only would achieve adequate PV isolation while demonstrating the critical role of the carina in PV isolation. METHOD: Sixty-six (66) consecutive patients with paroxysmal AF were included. Thirty-four (34) patients underwent wide antral circumferential ablation (WACA-only) and 32 underwent WACA+ (WACA + empiric carina isolation). All procedures were performed via single transseptal approach. Pulmonary vein isolation was confirmed with the use of a circular mapping catheter in both groups. RESULTS: Compared to WACA-only, WACA+ increased the odds of PV isolation from 65% to 94% (p=0.011). In the WACA-only procedure, ablation of the carina was needed to achieve PV isolation. At the 18-month follow-up (interquartile range 15.2-20.8 months), freedom from AF was 84% for the entire cohort. CONCLUSIONS: Our study confirmed the high success rate of PV isolation using the ablation index and showed that this can be achieved via a single transseptal crossing. Our study confirmed the role of the carina in PV isolation.

Radiofrequency Ablation of Atrial Fibrillation: Nonrandomized Comparison of Circular versus Point-by-Point "Smart" Ablation for Achieving Circumferential Pulmonary Vein Isolation and Curing Arrhythmic Symptoms.

INTRODUCTION: Pulmonary vein isolation (PVI) with radiofrequency (RF) ablation is now standard care for atrial fibrillation (AF). New improvements in PVI techniques include use of catheters that measure contact-force and circular ablation catheters. These techniques have not been compared. METHODS AND RESULTS: We compared the success rate of circumferential pulmonary vein isolation (CPVI) with: (1) "point by point" RF using an irrigated tip ablation catheter with "smart touch" contact-force; (2) irrigated nMARQ circular ablation catheter in 86 patients with AF. The endpoints of the study were acute and long-term success rate of CPVI. The 2 groups had similar characteristics: Smart Touch group with 50 patients, age 62 ± 8 years, 64% male; nMARQ group with 36 patients, 75% male, age 58.7 ± 10 years. The type of AF was similar in the 2 groups: paroxysmal and persistent in 68% and 32% in the Navistar group versus 64% and 36% in the nMARQ group. Follow-up periods were similar (18.4 months vs. 19 months, P = 0.59). All the pulmonary veins were successfully isolated in both groups. However, PVI could not be achieved with the nMARQ in 2.7% of the pulmonary veins ablated and was completed with a Smart Touch. The long-term success rate was comparable in the 2 groups. CONCLUSION: The nMARQ and Smart Touch catheters give similar results in PVI of both paroxysmal and persistent AF. The procedural time was shorter with the nMARQ in paroxysmal AF. Need for crossover from nMARQ to Smart Touch occurred in 2.7% of PVs ablated.