Background: Extracorporeal Membrane Oxygenation (ECMO) may facilitate extensive activation mapping of unstable ventricular tachycardia (VT) , provide hemodynamic support and eliminate the need for rescue shocks during the radiofrequency ablation (RFA). We report here our experience of 2 cases of ECMO assisted VT RFA .
Methods: Prior to RFA procedure ECMO was connected through cannulation of the femoral vessels, using long vein cannula (22/25 FR) located in the right atrium, and short arterial cannula (16/18 FR) located in the external iliac artery. The ECMO circuit was inserted in the contralateral groin of the one used for catheter placement, using standard groin incision and seldinger technique. RFA was done with a retrograde aortic approach. VT was induced to allow activation mapping and entrainment. Endpoint was non inducibility of any VT.
Results: Patient 1 had non ischemic cardiomyopathy (ISCMP) and presented with recurrent premature ventricular contraction (PVC) induced VT and ventricular fibrillation (VF). Each event resulted in cardiovascular collapse. His arrhythmias were unresponsive to multiple drugs and anesthesia. Patient 2 had ISCMP and presented with monomorphic VT storm. He had severe LV dysfunction and was in decompensated heart failure. Prior to procedure both patients were put on ECMO support. Blood flow was maintained at 1.5 L /min but during VT/VF was increased to 3 L/min. In both cases ECMO didn’t prevent VT inducibility. This permitted sufficient activation mapping for ablation of all inducible VTs. At termination the patients were easily weaned from the ECMO circuit. No peri-procedural complications occurred. During follow up (3 and 2 months respectively) both remained free from VT.
Conclusions: We report our first experience of VT RFA with ECMO support. ECMO allows VT mapping, is safe and prevents hemodynamic collapse during the procedure. A strong co-operation between electrophysiologists and cardiac surgery is pivotal to achieve satisfactory results.
