Modified energy settings are mandatory to minimize oesophageal injury using the novel multipolar irrigated radiofrequency ablation catheter for pulmonary vein isolation.
AIMS
The multipolar irrigated radiofrequency (RF) ablation catheter (nMARQ™) is a novel tool for pulmonary vein isolation (PVI). We investigated the incidence of thermal oesophageal injury (EI) using the nMARQ™ for PVI.


METHODS AND RESULTS
In the initial six patients (Group 1), RF was delivered at the posterior wall with a maximum duration of 60 s and a maximum power (maxP) of 20 W for unipolar ablation, and a maxP of 10 W for the bipolar ablation. In the latter 15 patients (Group 2), RF application was limited at the posterior wall to a maximum duration of 30 s and a maxP of 15 W for unipolar ablation a max P of 10 W for bipolar ablation. Oesophageal temperature monitoring was performed in all patients and ablation was terminated at a temperature rise >41°C. Endoscopy was carried out within 2 days post-ablation. Pulmonary vein isolation was performed during sinus rhythm and was successfully achieved in 83 of 84 PVs except the septal inferior vein in one patient. Charring was seen in 3 of 21 (14.3%) patients without any evidence of embolism. Phrenic nerve palsy occurred in one patient. Endoscopy revealed severe EI in 3 of 6 (50%) patients in Group 1 and in 1 of 15 patients (6.7%) in Group 2. Procedure times between Groups 1 and 2 were similar (228.3 ± 60.2 min vs. 221.3 ± 51.8 min; P = 0.79).


CONCLUSION
An unexpectedly high incidence of thermal EI was noted following PVI using the nMARQ™ with the initial ablation protocol. However, the incidence of thermal EI can be sigificantly reduced with limited power and RF application time at the posterior left atrium.
['Rillig|Andreas|A|', 'Lin|Tina|T|', 'Burchard|Andre|A|', 'Kamioka|Masashi|M|', 'Heeger|Christian|C|', 'Makimoto|Hisaki|H|', 'Metzner|Andreas|A|', 'Wissner|Erik|E|', 'Wohlmuth|Peter|P|', 'Ouyang|Feifan|F|', 'Kuck|Karl-Heinz|KH|', 'Tilz|Roland Richard|RR|']
D000368:Aged D001281:Atrial Fibrillation D002056:Burns D017115:Catheter Ablation D015331:Cohort Studies D022062:Electrophysiologic Techniques, Cardiac D004947:Esophagus D005260:Female D006801:Humans D015994:Incidence D008297:Male D008875:Middle Aged D011446:Prospective Studies D011667:Pulmonary Veins
Multipolar irrigated radiofrequency ablation Pulmonary vein isolation nMARQ™ Temperature monitoring Atrial fibrillation Catheter ablation Oesophageal lesion