Results of intraventricular resynchronization in patients with severe cardiac failure

Intraventricular resynchronization with pacemakers is a promising therapy for patients with refractory cardiac failure and intraventricular conductions delay. However its long term effects are not well known. To report the results of this therapy in patients with cardiac failure. Fourteen patients (11 male), whose mean age was 68 years, with a severe and refractory cardiac failure, have been treated in our unit using intraventricular resynchronization with pacemakers. Eight had a coronary heart disease and six a dilated myocardiopathy. The pacemaker was implanted transvenously, with conventional stimulation in atrium and right ventricle. The left ventricle was stimulated through an epicardial vein, accessed through the coronary sinus. In one patient the high thresholds did not allow a left ventricular stimulation. In the other 13 patients, a clinical improvement was observed in 11 (85%), that has been sustained for a mean of 8.2 months. The ejection fraction improved form 23.5 to 32.4% (p < 0.001), the 6 min walking test improved from 347 to 437 m (p = 0.003) and the functional capacity changes from 3.3 to 2.7 (p < 0.001). Three patients died during follow up. One was the patient in whom the stimulation failed and two had a sudden death. No complications of the procedure were observed. In this series, intraventricular resynchronization with pacemakers was effective in 11 of 13 patients, improving functional capacity and ejection fraction. Sudden death could be avoided adding a defibrillator to the pacemaker system.