Ventricular resynchronization: comparing biventricular and bifocal right ventricular pacemakers.

OBJECTIVE To analyze the conventional biventricular pacing (BV) and the bifocal (BF) right ventricular (RV) pacing, and to perform a comparative analysis of these two techniques in relation to clinical, functional and echocardiographic parameters in a population without the exclusion criteria of the major studies. METHODS A prospective non-randomized analysis of 36 patients undergoing surgery for multisite pacemaker implantation due to QRS > or =130 ms, severe left ventricular dysfunction, and NYHA functional class III or ambulatory class IV congestive heart failure was performed. RESULTS Favorable results of resynchronization were obtained with both techniques, with no significant differences in the comparison of the two groups, except for a higher QRS narrowing in the BV group, and a trend of a lower number or hospital admissions in the BV group. When the groups were analyzed separately and compared before and after the procedures, we observed that improvement was much more significant in the biventricular group, as were the more statistically relevant rates. CONCLUSION Cardiac resynchronization therapy proved to be an efficient therapy in both groups analyzed, although with more significant outcomes in the biventricular group.