Ablation of ischemic VT - Strategies and prognosis

Dr. Gábor Duray is a consultant in clinical cardiac electrophysiology at J. W. Goethe University, Frankfurt am Main, Germany. Dr. Duray received his medical degree in 1997 from the Semmelweis University of Medicine in Budapest, Hungary. He completed his training in internal medicine in 2002 and in cardiology in 2005. He has been involved in cardiac electrophysiologic studies and catheter ablations since his graduation. Beside clinical follow up of ICD and pacemaker patients, he started with pacemaker and ICD implantations in 2003. After several short-term training and research fellowships during and after his graduation (Cleveland, Ohio; Innsbruck, Austria; Homburg (Saar), Germany; Vienna, Austria), he took up a position as clinical electrophysiologist at the J.W.Goethe University, in Frankfurt, Germany. He is an accredited European Cardiologist, received accreditation in Interventional Cardiac Pacing and in Invasive Electrophysiology by the European Heart Rhythm Association (EHRA) and was elected as a member of theEHRA. He authored and co- authored 19 articles.

Abstract

Radiofrequency (RF) catheter ablation is an option to control recurrent ventricular tachycardias (VT) in patients with structural heart disease usually as an adjunct to implantablecardioverter defibrillator (ICD) therapy. The first step of the ablation is the localization of the myocardial scar area in sinus rhythm, minimizing the time spent in VT. During composition of a 3 dimensional voltage (amplitude) map, special care is taken to identify areas with late potentials and fractionated potentials. Pace mapping is performed to identify low amplitude, excitable areas; slow conduction zones, possible isthmus zones and exit areas. A VT induction is suggested in the area of the exit point of the tachycardia. In case of hemodynamically unstable VT short entrainment or RF energy delivery may be attempted for VT termination. If the VT hemodynamically stable detailed entrainment mapping and activation mapping during VT is possible resulting in more exact identification of critical areas in the VT. The ablation of the exit point and / or isthmus areas may be performed in sinus rhythm in ongoing VT. The mortality of the patients with ischemic cardiomyopathy with recurrent, drug refractory VT remains significant, although a recent study suggested a better outcome in patients undergoing catheter ablation.