Biventricular Pacing by Transvenous Route in Patients with Dilated Cardiomyopathy

Biventricular pacing has recently been suggested as a treatment modality in patients with dilated cardiomyopathy. Left ventricular stimulation can be achieved by transvenous route, but acute and long-term follow-up data of this new method is limited. The aim of the study was to evaluate the feasibility and long-term safety of biventricular pacing by the transvenous route. Biventricular pacemaker implanted via transvenous route in patients with dilated cardiomyopathy (left ventricular EF < 40%, end-diastolic diameter > 55 mm) presented with advanced congestive heart failure (NYHA III-IV) and intraventricular conduction delay (QRS > 120 msec). Biventricular pacemaker was successfully implanted in 26 of 29 patients (89%). The mean biventricular pacing threshold, sensing and electrode impedance during the implantation were measured 1.8±0.7 V, 15±7 mV and 626±194 Ohm, respectively. The average procedural time of left ventricular lead implantation was 54±24 min (24-110 min) and fluoroscopy time 28±14 min (12-67 min). Left ventricular electrode dislocation occurred in four patients. Intermittent or diaphragmatic stimulation were observed in two patients. A second operation was performed in four of these patients and reposition of left ventricular leads was successfully accomplished in three of them. Biventricular pacing threshold, sensing and electrode impedance were suitable for permanent biventricular stimulation over follow-up (mean 12±7, range 3 to 27 months). So permanent biventricular stimulation were obtained in 23 of 29 patients (79%). It has been concluded that permanent biventricular pacing by the transvenous route in patients with dilated cardiomyopathy can be accepted as a feasible and safe method.