X-ray exposure in cryoballoon versus radiofrequency ablation for atrial fibrillation over 7 years: A single center study.

Background: Facing an increasing number of radiofrequency ablation (RF) and cryoballoon ablation (CB) procedures for treatment of AF radiation exposure and its reduction is a focus point for interventional electrophysiologists. Objective: This study evaluated the procedural parameters of the different ablation methods focusing on radiation exposure and the BMI of the patients. Methods: One thousand one hundred and thirty-three first procedural cases of pulmonary vein isolation in patients with paroxysmal and persistent AF treated with RF and CB-based techniques were analyzed retrospectively over a period of 7 years focusing on the endpoints dose area product (DAP, cGycm2), fluoroscopy time (FT, min) and procedural time (PT, min). Results: Of the 1133 patients (mean age 63.4 ± 11.4 years, BMI 28.9 ± 4.7) 335 patients received an RF procedure, 211 patients were treated with the cryoballoon first generation (CB1), and 587 patients with cryoballoon second generation (CB2), respectively. The mean DAP for the PVI was 508 ± 654 cGycm2 in RF procedures, 1077 ± 683 cGycm2 in CB1-procedures, and 587 ± 489 cGycm2 in CB2-procedures with fluoroscopy times significantly shorter in RF procedures (9.6 ± 5.2 min) as compared to 17.7 ± 5.9 min in CB1- and 16.3 ± 6.3 min in CB2-procedures (p < .001). At the same time, the procedure duration using RF (115 ± 33.5 min) was significantly longer than both in CB1 (96 ± 16.8 min) and CB2 procedures (75 ± 15.9 min). Conclusions: Despite longer fluoroscopy durations in the CB technique, the CB2 resulted in a comparable low radiation exposure in PVI as compared to RF, accompanied by shorter procedure durations.

Transcoronary pacing in an animal model : Second coated guidewire versus cutaneous patch as indifferent electrodes.

BACKGROUND: Transcoronary pacing is a seldom used treatment option for unheralded bradycardias in the setting of percutaneous coronary interventions (PCI). In the present study we compared a coated guidewire inserted proximally into a coronary artery with a cutaneous patch electrode as indifferent electrodes for transcoronary pacing in a porcine model. METHODS: Transcoronary pacing was investigated in 7 adult pigs in an animal catheterization laboratory. A standard guidewire insulated by a monorail-balloon was advanced into the periphery of a coronary artery serving as the cathode. As the indifferent anode, a special guidewire with electrical insulated by a polytetrafluoroethylene (PTFE) coating was positioned into the proximal part of the same coronary vessel. Transcoronary pacing parameters (threshold and impedance data and the magnitude of the epicardial electrogram) were compared with unipolar transcoronary pacing using a cutaneous patch electrode. RESULTS: Transcoronary pacing was successful against both indifferent electrodes. Pacing thresholds obtained with the coated guidewire technique (1.8 ± 1.3 V) were similar to those obtained by standard unipolar transcoronary pacing with a cutaneous patch electrode (1.8 ± 1.5 V). The impedance with the additional coated guidewire was 419 ± 144 Ω and thereby slightly higher compared to 320 ± 103 Ω obtained by pacing against the patch electrode (p < 0.05). Both settings yielded comparable R­wave amplitudes (8.0 ± 5.1 mV vs. 7.1 ± 3.6 mV). CONCLUSIONS: A second coated guidewire is as effective as a cutaneous patch electrode when added as an indifferent electrode in transcoronary pacing. This transcoronary pacing technique could replace temporary transvenous pacing in emergency situations during PCI, especially when using the radial approach.