PO-05-034 CLINICAL CHARACTERISTICS AND OUTCOMES AFTER VENTRICULAR TACHYCARDIA ABLATION USING ULTRALOW TEMPERATURE CRYOABLATION IN PATIENTS WITH PRIOR CATHETER ABLATION

Abstract

Ablation of scar mediated Ventricular Tachycardia (VT), especially when the location of circuit is intramural can be quite challenging with the use of radiofrequency (RF) ablation. Preclinical data with the use of Ultralow temperature Cryoablation has shown that it can create deep, transmural lesions and can generate temperature as low as -196° C. To present a series of patients who had recurrent VT despite prior RF ablation and then underwent VT ablation with Ultralow temperature cryoablation system (Adagio) as part of the FDA compassionate use authorization. We performed retrospective analysis of patients who had undergone VT ablation using the Adagio system. Follow up data on clinical outcomes and recurrence of VT episodes were collected based on clinic visits, device interrogations and remote transmissions from Implantable Cardioverter Defibrillators (ICDs). A total of 5 patients underwent Ultralow temperature cryoablation for VT between 10/2021 and 05/2022 at our institution. The average age of patients in our case-series was 72 +/- 8.6 years and 3 (60%) of patients had h/o ischemic cardiomyopathy. The median number of prior VT ablations performed per patient was 2, and 40% of patients had presented in electric storm. During the VT ablation procedure using the Adagio system, the average number of inducible VT episodes was 2.6 +/- 1.8. All 5 patients were non-inducible at the end of VT ablation. At an average follow up period of 207.6 +/- 77.7 days, after having undergone VT ablation using the Adagio system, all 5 patients remained free of ICD shocks or electric storm during the follow up period and only 2 patients were maintained on anti-arrhythmic therapy. One patient underwent cardiac transplant because of recurrence of relatively slow VT episodes and advanced congestive heart failure. It is also worthwhile to note that in this patient, given the inaccessible location of VT circuit (peri-mitral region after prior cardiac surgery for cardiac aneurysm), ablation lesions could not be optimally delivered. Another patient experienced 1 episode of slow monomorphic VT, which was ATP terminable. Although our experience is based on a small sample size, the follow up outcomes using Ultralow temperature Cryoablation system for VT ablation in a challenging patient subset with limited options seems promising. Future studies would yield data on efficacy and safety of this system in high-risk subset of patients.