Cryothermal energy demonstrates shorter ablation time and lower complication rates compared with radiofrequency in surgical hybrid ablation for recurrent ventricular tachycardia

Abstract

Background: Recurrent ventricular tachycardia (VT) after prior endocardial catheter ablation(s) presents challenges in the setting of prior cardiac surgery where percutaneous epicardial access may not be feasible.

Objective: The purpose of this study was to compare the outcomes of cryothermal vs radiofrequency ablation in direct surgical epicardial access procedures.

Methods: We performed a retrospective study of consecutive surgical epicardial VT ablation cases. Surgical cases using cryothermal vs radiofrequency ablation were analyzed and outcomes were compared.

Results: Between 2009 and 2022, 43 patients underwent either a cryothermal (n = 17) or a radiofrequency (n = 26) hybrid epicardial ablation procedure with direct surgical access. Both groups were similarly matched for age, sex, etiology of VT, and comorbidities with a high burden of refractory VT despite previous endocardial and/or percutaneous epicardial ablation procedures. The surgical access site was lateral thoracotomy (76.5%) in the cryothermal ablation group compared with lateral thoracotomy (42.3%) and subxiphoid approach (38.5%) in the radiofrequency group, with the remainder in both groups performed via median sternotomy. The ablation time was significantly shorter in those undergoing cryothermal ablation vs radiofrequency ablation (11.54 ± 15.5 minutes vs 48.48 ± 23.6 minutes; P < .001). There were no complications in the cryothermal ablation group compared with 6 patients with complications in the radiofrequency group. Recurrent VT episodes and all-cause mortality were similar in both groups.

Conclusion: Hybrid surgical VT ablation with cryothermal or radiofrequency energy demonstrated similar efficacy outcomes. Cryothermal ablation was more efficient and safer than radiofrequency in a surgical setting and should be considered when surgical access is required.

Keywords: Complications; Cryothermal ablation; Hybrid ablation; Recurrent ventricular tachycardia; Ventricular tachycardia.