Right ventricular rapid pacing in catheter ablation of atrial fibrillation: a novel application for cryoballoon pulmonary vein isolation.
BACKGROUND
Cryoballoon ablation (Arctic Front, Cryocath) represents a novel technology for pulmonary vein isolation (PVI). The initial phase of a freeze is crucial for cryolesion formation which is determined by local temperature depending on blood flow. We investigated the impact of right ventricular rapid pacing (RVRP) on temperature kinetics in patients (pts) with paroxysmal atrial fibrillation (PAF).


RESULTS
Right ventricular rapid pacing was performed from the RV apex. Absolute minimal temperature (MT, degrees C), temperature slopes [time (s) to 80% MT; dT/dt), area under the curve (AUC) and arterial blood pressure (ABP, mmHg) were compared (group I: with RVRP vs. group II: without RVRP). RVRP (mean duration 55 +/- 7 s) was performed in 11 consecutive PAF pts (41 PVs, age 58 +/- 9 years, LA size 44 +/- 6 mm, normal ejection fraction). Only freezes with identical balloon positions were analyzed (11/41 PVs). RVRP (cycle length 333 +/- 3 ms) induced a significant drop in ABP (group I: 45 +/- 3 mmHg vs. group II: 100 +/- 18 mmHg, p < 0.001). MT was not different between group I and group II (-45.0 +/- 4.4 vs. -44.3 +/- 3.4 degrees C, p = 0.46), whereas slope (38.0 +/- 4.6 s vs. 51.6 +/- 14.4 s, p = 0.0034) and AUC (1090 +/- 4.6 vs. 1181 +/- 111.2, p = 0.02) was significantly changed. In one pt, a ventricular tachycardia was induced. PVI was achieved in 41/41 PVs.


CONCLUSIONS
Right ventricular rapid pacing significantly accelerates cryoballoon cooling during the initial phase of a freeze possibly suggesting improved cryolesions.
Chun
K R Julian
KR
Department of Cardiology, Asklepios Klinik St Georg, Hamburg, Germany. jongichun@t-online.de
Fürnkranz
Alexander
A
Schmidt
Boris
B
Metzner
Andreas
A
Tilz
Roland
R
Zerm
Thomas
T
Köster
Ilka
I
Koektuerk
Buelent
B
Konstantinidou
Melanie
M
Ouyang
Feifan
F
Kuck
Karl Heinz
KH
D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy*; D002304:Cardiac Pacing, Artificial; D002404:Catheterization / Q000379:methods*; D003131:Combined Modality Therapy; D003452:Cryosurgery / Q000379:methods*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006339:Heart Rate; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome