47: Preemptive ECMO in high-risk patients for catheter ablation for ventricular tachycardia. A single center experience.

Introduction: There is a high-risk cohort of patients with refractory unstable ventricular tachycardia (VT). A main treatment modality for these patients is catheter ablation (CA). To perform the CA, it is necessary to activate the paroxysm of VT which can lead to hemodynamic collapse. This is especially problematic in patients with impaired myocardial contractility, such as ischemic or dilated cardiomyopathy. Methods: From July 2022 to July 2024, 12 cases of the catheter ablation for VT with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support were performed at E.N Meshalkin National Medical Research Center. Before CA, patients were assessed using the PAINESD score. VA-ECMO was used in patients with PAINESD score ≥ 15 points. The average age of patients was 61,4 ± 6,4 years. The cause of congestive heart failure (CHF) was ischemic cardiomyopathy in all patients. The average left ventricular ejection fraction was 27,5 ± 5,2 %, the average end-diastolic volume was 223 ± 54,5ml; 41,6 % of patients had concomitant heart valve pathology, 41,6% had CABG and 41,6% of patients had PCI in the anamnesis. Results: In all cases, VA-ECMO was weaned in the cath lab. The average ECMO time was 223 ± 58min. All patients required inotropic support after weaning the VA-ECMO. The average ICU time was 1,3 ± 0,5 days, and the average stay at the hospital was 10,4 ± 4,3 days. Mortality: one patient died in the hospital due to recurrent VT with an electrical storm, one patient died in 3 months because of decompensation of CHF, all other patients completed a six-month follow-up (by phone call), four patients completed a one-year follow-up. Conclusions: Preemptive ECMO is an effective measure for hemodynamic support in high-risk patients who require ablation of unstable VT. It allows successful mapping and catheter ablation with good clinical outcome.