We compared the effects of triple-site versus dual-site biventricular stimulation in candidates for cardiac resynchronization therapy.
Background
Conventional biventricular stimulation with a single right ventricular (RV) and a single left ventricular (LV) lead is associated with persistence of cardiac dyssynchrony in up to 30% of patients.
Methods
This multicenter, single-blind, crossover study enrolled 40 patients (mean age 70 ± 9 years) with moderate-to-severe heart failure despite optimal drug treatment, a mean LV ejection fraction of 26 ± 11%, and permanent atrial fibrillation requiring cardiac pacing for slow ventricular rate. A cardiac resynchronization therapy device connected to 1 RV and 2 LV leads, inserted in 2 separate coronary sinus tributaries, was successfully implanted in 34 patients. After 3 months of biventricular stimulation, the patients were randomly assigned to stimulation for 3 months with either 1 RV and 2 LV leads (3-V) or to conventional stimulation with 1 RV and 1 LV lead (2-V), then crossed over for 3 months to the alternate configuration. The primary study end point was quality of ventricular resynchronization (Z ratio). Secondary end points included reverse LV remodeling, quality of life, distance covered during 6-min hall walk, and procedure-related morbidity and mortality. Data from the 6- and 9-month visits were combined to compare end points associated with 2-V versus 3-V.
Results
Data eligible for protocol-defined analyses were available in 26 patients. No significant difference in Z ratio, quality of life, and 6-min hall walk was observed between 2-V and 3-V. However, a significantly higher LV ejection fraction (27 ± 11% vs. 35 ± 11%; p = 0.001) and smaller LV end-systolic volume (157 ± 69 cm3 vs. 134 ± 75 cm3; p = 0.02) and diameter (57 ± 12 mm vs. 54 ± 10 mm; p = 0.02) were observed with 3-V than with 2-V. There was a single minor procedure-related complication.
Conclusions
Cardiac resynchronization therapy with 1 RV and 2 LV leads was safe and associated with significantly more LV reverse remodeling than conventional biventricular stimulation.
Abbreviations and Acronyms
AF
atrial fibrillation
AV
atrioventricular
CHF
congestive heart failure
CRT
cardiac resynchronization therapy
CS
coronary sinus
LV
left ventricle/ventricular
LVEF
left ventricular ejection fraction
LVESV
left ventricular end-systolic volume
NYHA
New York Heart Association
QOL
quality of life
RV
right ventricle/ventricular
2-V
dual-site
3-V
triple-site
6-MHW
6-min hall walk
Cited by (0)
This study was sponsored by St. Jude Medical, Zaventem, Belgium.