TUGENDHAT: a pilot randomized study on effects of biventricular pacing in patients with bradycardia pacing indication and normal systolic function on heart failure, atrial fibrillation and quality of life (results of 12 month follow-up)

Abstract

Since the late 1990s, a growing number of clinical studies have indicated that long-term permanent right ventricular (RV) apical pacing will induce severe complications such as development of heart failure, increased burden of atrial fibrillation leading to decreased quality of life. To investigate whether cardiac resynchronization therapy (CRT) using biventricular (BiV) pacing can prevent the development of left ventricular (LV) dysfunction, LV remodelling, worsening of the clinical status and quality of life in chronically RV paced patients with normal LV ejection fraction (EF). A total of 127 patients with Class I indication for permanent cardiac pacing and without established indication for CRT were subjected to 6 months of RV and BiV pacing in a patient-blinded, randomized crossover trial. Treatment effects of BiV pacing were evaluated for LV function, LV remodelling and clinical status. As compared with RV pacing, BiV pacing did not significantly prevent the decrease of LV function [LVEF 61.0 % (36.0; 68.0) vs 60.5 % (38.5; 67.5) in RV pacing], did not change the functional class according to the New York Heart Association [52 % in Class II vs 53.9 % in Class II in RV pacing, and 3.9 % in Class III vs 6.9 % in Class III in RV pacing], and did not present any changes in quality of life [32.5 (18.0; 80.0) vs 32.0 (21.0; 47.0) indexes in RV pacing]. BiV pacing, compared to RV pacing, did not change LV function and quality of life in patients with the absence of LV dysfunction or remodelling, standard bradycardia pacing indications in a pilot phase (12- month follow-up) of the TUGENDHAT trial. The final report will be published after 60-month follow-up termination (Tab. 5, Fig. 3, Ref. 30).