Objectives and Background: Atrial fibrillation (AF) is still associated with higher recurrence rate. This is prospective study of Redo pulmonary vein isolation (PVI) combined with remote magnet navigation. We have done high density mapping and in retrospective Analysis we tried to find criteria for better Ablation success. Materials and Methods: 50 patients (male 36, female 14) with indication for Redo-PVI ware included. A 20 polig multielectrode catheter was used for mapping. Mapping data were collected bevor and after ablation and processed in terms of low-voltage areas bipolar (3 groups: 0.05-0.15 mV, 0.15-0.25 mV, 0.25-0.5 mV) and change in unipolar amplitude at the ablation lesions. The primary endpoint (symptom freedom at 12 months) was evidenced by follow-up examinations at 3, 6,9,12 months. Non-parametric statistical methods were used for variables with non-normal distributions. Trends in success rates were evaluated using the Kaplan-Meier methodology and compared using a log-ranking test. Results: In all analysed low-voltage bipolar groups occurs a change in the distribution after ablation in patients with AF. There are 3 parameters which related with endpoint: area of bipolar signals 0.05-0.15 mV (Me +32%, [95% CI: -10% to +167%], p<0.001), the unipolar amplitude at the applied ablation lesions (Me -0.45mV [95% CI: -0.15 to -1], p<0,001) and unipolar amplitude at the attached ablation lesions (lower amplitude was with recurrence associated, p=0.004). According to ROC analysis and logistic regression: failure to meet all 3 criteria accompanied with a 67% probability of symptomatic recurrence, if all 3 criteria are met, it is expected to have an approximately 81% success rate within the 12 months. Conclusion: Analysis of a high-density map including 3 criteria, help us to improve ablation success.

No abstract

Funding Acknowledgements Type of funding sources: None. Background Standard unipolar catheter ablation (UPA) with radiofrequency for ventricular arrhythmias has reportedly recurrence rates due to a lack of efficient lesions in the deep myocardial substrates to disrupt the critical components of the arrhythmia circuit. First in-vivo bipolar catheter ablations (BPA) show promising results to counter this issue. Precise handling of two catheters simultaneously during BPA is a challenge that the utilization of a robotic magnetic navigation (RMN) system could make safer by robotically controlling one of the catheters. Method A RMN ablation catheter with a 3.5 mm irrigated tip (RMN Navistar Thermocool, Biosense Webster), as an active catheter, as well as an indifferent manual catheter 3.5 mm irrigated non-nav ablation catheter (Celsius Thermocool, Biosense Webster) was connected to a BPA-certified generator system (HAT 500® system (OSYPKA, Germany)). The RMN catheter was controlled by a RMN Stereotaxis- system. A 3D Carto system combined with a VIVO system was used to find the right localization. Results 70-year-old male with ischemic CMP, EF nearly 40%, revascularized through CABG, presented after 4 attempts of ablation of very frequent symptomatic monomorphic PVCs (more than 30000 /24h), with different approaches in different hospitals. The origin of PVCs was mid-septal RV/LV. After LAT Mapping in a transseptal approach with the RMN Catheter (LV), the manual catheter was placed at the opposite site in the RV. Bipolar Ablation was done at 30W (3 min) with acute suppression of the PVCs. The follow-up duration was 6-months with still lasting good result. No complications occurred. Conclusions BPA ablation is an additional energy option in difficult cases. With a RMN system is it feasible and safe. The robotic control of one of the two ablation catheters provides a precise and stable execution of the BPA since the operator only needs to control the second catheter manually while the magnetic field holds the first in place. It therefore also allows a single operator approach.

ABSTRACT. PentaRays catheters (Biosense Webster, Diamond Bar, CA) create high-density electroanatomical maps, and remote magnetic navigation (RMN) (Niobe Epocht, Stereotaxis Inc., St. Louis, MO) enables intricate manipulation of magnetic ablation catheters. The purpose of this study was to assess the feasibility of PentaRay s used in combination with RMN ablation for pulmonary vein isolation (PVI). In 21 paroxysmal atrial fibrillation (AF) patients undergoing PVI, a PentaRay s catheter was used to map the left atrium in sinus rhythm at baseline and post PVI. The Navigant Ablation History module (Stereotaxis Inc., St. Louis, MO) was used to help create connected ablation lines, pacing from the ablation catheter (ThermoCool RMT, Biosense Webster, Diamond Bar, CA) was performed to examine the presence of exit block, and voltage maps from the PentaRay s were used to demarcate low-voltage areas where bipolar voltages were within 0.25-0.5 mV. This information was assessed to identify potential PVI gaps, and additional ablation points were delivered as necessary. Complete PVI was achieved in 21 out of 21 patients (100%). The average initial mapping time was 12.4 ± 2.7 min spanning 1,726 ± 476 points. Similarly, the average remap time was 14 ± 4.3 min spanning 1,928 ± 842 points. There were no procedural complications associated with this study. This study demonstrates the feasibility of this clinical workflow using both a high-density multi-electrode mapping catheter and an RMN ablation catheter for PVI. The combination might be a useful strategic choice for treatment of AF.