Co-Author(s):
Daniel Alexander, DO - Winchester Medical Center
Rebekah Smith, RN - Winchester Medical Center
Erik Kulstad, MD, MS - UT Southwestern Medical Center
Winchester Medical Center
Winchester Medical Center, 1840 Amherst Street, Winchester, VA 22601
Introduction | Objectives: Electrical isolation of the pulmonary veins utilizing the Cryoablation balloon (Arctic Front, Medtronic) has been established as an effective treatment for both paroxysmal and persistent atrial fibrillation (AF). Esophageal injury as a result of convective thermal transfer is a rare, but potentially fatal complication of both radiofrequency and cryoablation techniques. Active warming of the esophagus during cryotherapy offers a proactive approach to countering potential cryothermal injury which does not require repositioning during use.  This prospective study (NCT04087122) measured the difference in procedure time between patients treated with and without an esophageal warming device while undergoing cryoablation for the treatment of AF.
Methods: Patients scheduled for cryoablation were consented for enrollment, with cryoablation performed in standard fashion with the exception of the placement of an active esophageal warming device in place of the standard temperature sensor.  Warming device temperature was set to 42°C.  Procedure times, left atrial time, and fluoroscopy usage for each case were then compared to the previous consecutive cryoablation control patients.
Results: A total of 20 patients were prospectively enrolled and received active esophageal warming in place of standard LET monitoring.  Mean total procedure time was 126 minutes (95% CI 112 to 139 minutes) and median time was 119.5 minutes (IQR 29 minutes).  A total of 25 patients served as historical controls, with mean total procedure time of 141 minutes (95% CI 126 to 156 minutes), and median time of 132 minutes (IQR 28 minutes), p=0.03, Mann-Whitney U Test.  Time from transeptal access to last pacing maneuver to confirm exit block (used as a surrogate for left atrial time); and the total fluoroscopy time were shorter in the active esophageal warming group by 5% and 6% respectively.  These trended towards, but did not reach, statistical significance.   In one and three month follow up, no complications, including stroke or esophageal injury were identified.
Conclusions: Use of active esophageal warming avoids the need for procedural interruptions and temperature probe repositioning, which appears to improve efficiency by reducing total procedure time.