Long-term reproducibility of ventricular tachycardia induction with electrophysiological testing in patients with coronary heart disease and depressed left ventricular ejection fraction

The Multicenter Automatic Defibrillator Implantation Trial (MADIT) has rece ntly confirmed the role of programmed ventricular stimulation (PVS) to iden tify the high risk patients of sudden death after myocardial infarction and to prevent this risk. The purpose of this study was to evaluate the long-t erm reproducibility of PVS in these patients. Thirty patients with coronary heart disease without spontaneous documented sustained ventricular tachyca rdia (VT) underwent two programmed stimulations in the absence of antiarrhy thmic drug treatment between 2 and 6 years (mean 4 years). No patient had a myocardial infarction or intervening cardiac surgery during this period. T he protocol of study was similar using up to three extrastimuli in two site s of the right ventricle, delivered in sinus rhythm and driven rhythm (600 ms, 400 ms, respectively). On the first PVS, 17 patients had inducible sust ained VT (group I). Thirteen patients did not have inducible VT(group II). On the second PVS all group I patients but one had inducible VT, but the cy cle length was significantly modified in 2 2. In group a five patients had inducible VT and in the other patients the PVS remained negative. In conclu sion, in patients with coronary heart disease, but without documented VT, t he long-term reproducibility of PVS was excellent in those with inducible V T (94 %); the patients remain at risk of VT and a prophylactic implantable cardioverter defibrillator could be considered. In patients with initially negative study, reproducibility of PVS was lower (61.5 %), probably because of the progressive remodeling after myocardial infarction. Therefore, the occurrence of new symptoms in patients with previously negative study requi res a second programmed ventricular stimulation.