Abstract 17075: Second Generation Cryoballoon Ablation With Improved Freezing Results in Pulmonary Injury and Unexpected Late Adhesion
Background: Cryoballoon ablation has become widely used for the treatment of atrial fibrillation. A second-generation cryoballoon, Arctic Front Advance Cryoballoon (AFAC) (Medtronic CryoCath LP Montreal Canada), has a larger refrigerant distribution and improved success rate of pulmonary vein (PV) isolation. Initial observations of increased potential complications have been reported compared to the first-generation Arctic Front Cryoballoon (AFC), but the cause and incidence is unknown.
Methods: Single center retrospective review of 80 patients, 40 ablated with AFC and 40 ablated with AFAC with standard 4 minute dosing, was compared. Late adhesion of cryoballoon, defined as the persistence of the frozen distal portion of the cryoballoon to the PV, assessed by intracardiac ultrasound, after ablation beyond the preset 20° Celsius (C), was analyzed. The post-operative symptomatic follow-up within 1 month was reviewed. Ablation time, nadir temperature, and time to complete thaw were compared and correlated.
Results: AFAC ablations have an average of 8°C colder nadir temperature compared to AFC ablations (-47+-4 vs. -39+-3). Late adhesion was noted in 0/320 PV (0%) of AFC ablation compared to 63/320 PV (19.7%) with AFAC ablation. Significant late adhesion of greater than 30 seconds post balloon deflation was noted in 25/63 (39.7%) (range 30 to 80 seconds). Predictors for prolonged freezing time includes lower nadir temperature (average -41 C vs. -48 C) and vein size of less than 20mm. Significant complaints of post-operative non-productive cough were noted in 11 of 40 (28%) of AFAC ablations compared to 2 of 40 (4%) of AFC.
Conclusions: Significant late adhesion was observed in AFAC ablation, frequently up to 80 seconds after balloon deflation. Mechanical manipulation must be avoided until complete catheter thaw to avoid mechanical trauma. Increased non-productive cough post ablation with AFAC may be secondary to collateral injury. Reducing ablation time may be able to reduce late adhesion and pulmonary complications. Further study is needed to improve assessment of complete thawing and dosing of AFAC.
- © 2013 by American Heart Association, Inc.