A randomized double-blind crossover trial of triventricular versus biventricular pacing in heart failure.
OBJECTIVE
A significant proportion of patients implanted with biventricular (BiV) devices fail to respond. Clinical response may be improved by additional ventricular stimulation sites. This single-centre, double-blinded randomized crossover trial aimed to determine whether long-term multisite ventricular pacing is superior to conventional BiV pacing in heart failure patients.


RESULTS
A total of 43 patients referred for cardiac resynchronization therapy (CRT) underwent transvenous implantation of a triventricular (TriV) device. Pacing leads were positioned in the right ventricular (RV) apex and a lateral coronary sinus (CS) branch, with a third ventricular lead implanted in a further lateral CS branch in 23 patients (group A) and on the high RV septum in 20 patients (group B). Devices were programmed in a randomized order to four pre-determined pacing configurations: conventional BiV, TriV, and dual-site and single-site left bentricular (LV) or RV pacing for 3-month periods with clinical and echo assessment at the end of each period. The primary endpoint was the comparison of 6 min walk distance (6MW) after 3 months of BiV vs. TriV pacing; secondary endpoints were Minnesota Living With Heart Failure (MLWHF) scores, and LV dimensions and function. The 12-month follow-up period was completed by 37 patients. Compared with BiV pacing, TriV pacing resulted in significant improvements in 6MW (451 ± 112 m vs. 425 ± 119 m, P = 0.008), MLWHF (32 ± 19 vs. 38 ± 24, P = 0.036), LV end-systolic volume (158 ± 79mL vs. 168 ± 76 mL, P < 0.05), and ejection fraction (30 ± 8% vs. 27 ± 8%, P < 0.05).


CONCLUSIONS
TriV pacing was associated with significant improvements in clinical and echocardiographic parameters compared with BiV pacing.
The Heart Hospital, Institute of Cardiovascular Medicine, University College London Hospital, London, UK.
Dominic P S
DP
Rogers
Pier D
PD
Lambiase
Martin D
MD
Lowe
Anthony W C
AW
Chow
D002304:Cardiac Pacing, Artificial / Q000009:adverse effects / Q000379:methods*; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000379:methods*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000628:therapy*; D006801:Humans; D008297:Male; D016896:Treatment Outcome