Search

Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): CardioFocus Background The endoscopic ablation system (EAS) is an established ablation device for pulmonary vein isolation (PVI) in patients with paroxysmal and persistent atrial fibrillation (AF). In randomized studies, however, point-by-point laser ablation resulted in longer procedure times. The novel X3 EAS is now equipped with a motor driven laser generator that sweeps the diode laser beam around the individual PV ostium at a pre-defined speed (2.25°/sec) thus allowing for contiguous circumferential ablation (RAPID mode). Purpose To determine the feasibility of single sweep ablation using the new X3 EAS. Methods Consecutive AF patients were enrolled. After single transseptal puncture selective PV angiographies were performed. A 3D enabled circular mapping catheter was used to record PV potentials and to create a 3D map of the left atrium. Then, the transseptal sheath was exchanged for the 12F EAS delivery sheath. The EAS was inflated to obtain optimal circumferential contact to the PV ostium. Before ablation, the laser generator was retracted to ensure optimal contact behind the catheter shaft (blind spot). Ideally, RAPID mode ablation was employed at 13-15W. In case of esophageal heating >39°C or suboptimal tissue exposure point-by-point ablation (5.5-12W for 20-30 secs) was used instead. During ablation at the septal PVs phrenic nerve pacing was performed via a diagnostic catheter in the superior vena cava. Single sweep ablation was defined as one single RAPID energy application per PV to complete the singular, circular lesion set. PV conduction was re-assessed after all PVs had been treated. In case of residual PV conduction, gap mapping followed by EAS guided ablation was performed. If EAS failed to achieve complete PVI, touch up ablation was allowed at the discretion of the operator. Hemostasis was achieved by means of a figure of 8 suture. Procedure time was defined as initial groin puncture to groin closure. Follow-up included office visits at 3, 6 and 12 months including 72 h Holter monitoring. Results One-hundred AF patients (56% male, mean age 6810 years, 66% PAF) with normal LV ejection fraction (mean 60 ± 10%) and normal LA size (41 ± 6mm) underwent X3 EAS ablation. Of 382 PVs 378 (99%) were isolated with the X3 EAS. In 214 PVs (56%) single sweep isolation was achieved. First pass isolation and RAPID mode only PVI was achieved in 362 (95%) and 357 (94%), respectively. Single sweep isolation rates varied across PVs from 46% at LIPV to 64% at RSPV. The mean total procedure and fluoroscopy times were 43 ± 10 and 4 ± 2 mins, respectively. Safety data and the complete follow-up will be reported. Conclusion The new X3 EAS equipped with a motor driven laser generator allows for single sweep PVI in 56% of PVs. Almost all PVs (94%) may be isolated with RAPID mode only leading to a very high first pass isolation rate. Altogether, this leads to substantially faster procedure times compared to the predecessor EAS.

Funding Acknowledgements Type of funding sources: None. Background A novel irrigated RF balloon (RFB) for pulmonary vein isolation (PVI) was recently released in selected centers . It is a 28 mm open irrigated balloon with 10 unipolar electrodes on its surface to deploy a circular ostial lesion set around the PVs. An inner lumen spiral catheter allows for real time PVI visualization during the ablation. Methods Data from consecutive RFB procedures were collected and analysed. After a single transseptal puncture and selective PV angiograms a 3D map of the left atrium was acquired. Sequential PVI was performed using the RFB: each application lasted 60 seconds, the posterior electrodes were identified to stop the energy delivery after 20 seconds. Real time to isolation data were acquired. A 3D bipolar remap was finally performed to observe the level of isolation. A temperature probe was used to monitor the local esophageal temperature (LET) with a cut off of 39°C. Acute procedural data and complication were collected. Endoscopy was scheduled the day after procedure. Results Data from 10 consecutive RFB procedures were analyzed: 6/10 patients were male, 67 ± 9 years old, 8/10 with history of paroxysmal AF. A total of 36 PVs were targeted and isolated with the RFB, with a mean of 7,3 ± 4,0 applications per patient and 2,0 ± 1,2 applications per PV. First pass "single shot" isolation was achieved in 22/36 (61%), time to isolation during the first application was observed in 29/36 (80%) PVs, but an acute reconnection was observed in 10/29 (35%) isolated PVs. Mean time to sustained isolation was 13 ± 5 sec., mean time to non-sustained isolation was significantly longer (29 ± 17 sec; p = 0,001). Procedure time was 57 ± 16 min., left atrial dwell time 50 ± 14 min, ablation phase time 29 ± 14 min and fluoroscopy time was 10 ± 4 minutes. An esophageal temperature above 39°C was recorded in 2/36 PVs. No phrenic nerve palsy was recorded. 7/10 patients underwent endoscopy and no thermal lesions were detected. No other complications were recorded. Conclusion The novel irrigated RFB seems to allow an effective, safe and fast pulmonary vein isolation. More studies are needed to optimize energy dosing to possibly increase the rate of durable single shot PVI.

Funding Acknowledgements Type of funding sources: None. Objectives To evaluate the feasibility, procedural data, and lesion characteristics of anterior line (AL) and roof line (RL) ablation by using ablation index (AI) guided high-power(50W) among patients with recurrent atrial fibrillation (AF) or atrial tachycardia (AT) after pulmonary vein isolation (PVI). Methods 35 consecutive patients with macro-reentrant left atrial tachycardia (LAT) or substrate at LA anterior wall or roof after previous PVI were enrolled. Ablation power was set to 50W, targeting AI 500 for AL and 400 for RL. First-pass conduction block (FPB) was evaluated. The AL was arbitrarily divided into 3(caudal, middle and cranial) segments to analyze the location of conduction gaps in non-FPB patients. Results A total of 32 AL and 17 RL were deployed and FPB was achieved in 24 (75%) and 14 (82%) of them respectively. In non-FPB group, the most frequent gap location along the AL was the middle third. Final block of AL was achieved in 97%, and block of RL was achieved in 100%. The RF ablation time was short (2,9 ± 0,8 min for AL and 46,2 ± 15,6 sec for RL). For AL, female gender was significantly more frequent in FPB than in non-FPB patients(p 0,028); patients with non-FPB were associated with significantly longer RF time as compared to patients with FPB (204 ± 47 sec vs 161 ± 41 sec; p = 0,02). No procedural complications occurred. Conclusion AI guided high-power(50W) ablation appears to be a feasible, effective and fast technique for AL and RL ablation.