Right ventricular outflow versus apical pacing in pacemaker patients with congestive heart failure and atrial fibrillation.
BACKGROUND
Prior studies suggest that right ventricular apical (RVA) pacing has deleterious effects. Whether the right ventricular outflow tract (RVOT) is a more optimal site for permanent pacing in patients with congestive heart failure (CHF) has not been established.


RESULTS
We conducted a randomized, cross-over trial to determine whether quality of life (QOL) is better after 3 months of RVOT than RVA pacing in 103 pacemaker recipients with CHF, left ventricular (LV) systolic dysfunction (LV ejection fraction < or = 40%), and chronic atrial fibrillation (AF). An additional aim was to compare dual-site (RVOT + RVA, 31-ms delay) with single-site RVA and RVOT pacing. QRS duration was shorter during RVOT (167 +/- 45 ms) and dual-site (149 +/- 19 ms) than RVA pacing (180 +/- 58 ms, P < 0.0001). At 6 months, the RVOT group had higher (P = 0.01) role-emotional QOL subscale scores than the RVA group. At 9 months, there were no significant differences in QOL scores between RVOT and RVA groups. Comparing RVOT to RVA pacing within the same patient, mental health subscale scores were better (P = 0.03) during RVOT pacing. After 9 months of follow-up, LVEF was higher (P = 0.04) in those assigned to RVA rather than RVOT pacing between months 6 and 9. After 3 months of dual-site RV pacing, physical functioning was worse (P = 0.04) than during RVA pacing, mental health was worse (P = 0.02) than during RVOT pacing, and New York Heart Association (NYHA) functional class was slightly better (P = 0.03) than during RVOT pacing. There were no other significant differences between RVA, RVOT and dual-site RV pacing in QOL scores, NYHA class, distance walked in 6 minutes, LV ejection fraction, or mitral regurgitation.


CONCLUSIONS
In patients with CHF, LV dysfunction, and chronic AF, RVOT and dual-site RV pacing shorten QRS duration but after 3 months do not consistently improve QOL or other clinical outcomes compared with RVA pacing.
Stambler
Bruce S
BS
University Hospitals of Cleveland, Case Western Reserve University, 22200 Euclid Avenue, Cleveland, Ohio 44106, USA. bss4@po.cwru.edu
Ellenbogen
KennethA
K
Zhang
Xiaozheng
X
Porter
Thomas R
TR
Xie
Feng
F
Malik
Rajesh
R
Small
Roy
R
Burke
Martin
M
Kaplan
Andrew
A
Nair
Lawrence
L
Belz
Michael
M
Fuenzalida
Charles
C
Gold
Michael
M
Love
Charles
C
Sharma
Arjun
A
Silverman
Russell
R
Sogade
Felix
F
Van Natta
Bruce
B
Wilkoff
Bruce L
BL
D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D018592:Cross-Over Studies; D006333:Heart Failure / Q000175:diagnosis* / Q000209:etiology / Q000628:therapy*; D006352:Heart Ventricles / Q000294:innervation*; D006801:Humans; D010138:Pacemaker, Artificial; D011788:Quality of Life; D016037:Single-Blind Method; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*