Introduction: Pulmonary vein (PV) isolation is the mainstay of catheter treatment of atrial
fibrillation (AF). The CoolLoop® cryoablation catheter (AFreeze® GmbH;
Innsbruck, Austria) was developed to create wide and complete circular lesions
around the PVs. In this study we evaluated feasibility and safety of this novel
ablation system in humans.
Methods: 10 patients (6M/4F; 57.6±7.6y) with paroxysmal AF were included in 2 referral centers.
The CoolLoop® catheter was positioned at each PV antrum using a steerable
transseptal sheath. Subsequently, 2-6 double-freezes over
5min were performed at each vein and PV-isolation was assessed
thereafter using a circular mapping catheter. During cryoablation of the right
PVs, pacing was used to monitor phrenic nerve function.
Results: The CoolLoop® catheter could be successfully positioned at each PV. A mean of
5.6±1.8 cryoablations were performed in the LSPV, 5.2±1.6 in the LIPV, 6.3±2.5
in the RSPV and 5.4±1.6 in the RIPV, respectively. Mean
procedure time was 251±60min and mean fluoroscopy time was 44.0±13.2min. 6 / 10
LSPV, 6 / 10 LIPV, 5 / 10 RSPV and 6 / 10 RIPV could be isolated exclusively
using the novel cryoablation system. One patient developed groin hematoma and a
brief episode of ST-elevation due to air embolism was observed in another subject.
No other clinical complications occurred during 3 months of follow up.
for paroxysmal atrial fibrillation using the CoolLoop® catheter is feasible and
appears safe. Clinical long term efficacy still needs to be evaluated and will
be compared with established catheters used for AF ablation.
Credits: Markus Stuehlinger; Simon Hoenig; Karin Spuller; Christian Koman; Markus Stoeger; Gerhard Poelzl; Hanno Ulmer; Otmar Pachinger; Clemens Steinwender