title: Right ventricular outflow versus apical pacing in pacemaker patients with congestive heart failure and atrial fibrillation.
abstract: 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.
authors.affiliation: University Hospitals of Cleveland, Case Western Reserve University, 22200 Euclid Avenue, Cleveland, Ohio 44106, USA. bss4@po.cwru.edu
authors.forename: Bruce S
authors.initials: BS
authors.lastname: Stambler
authors.forename: KennethA
authors.initials: K
authors.lastname: Ellenbogen
authors.forename: Xiaozheng
authors.initials: X
authors.lastname: Zhang
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Porter
authors.forename: Feng
authors.initials: F
authors.lastname: Xie
authors.forename: Rajesh
authors.initials: R
authors.lastname: Malik
authors.forename: Roy
authors.initials: R
authors.lastname: Small
authors.forename: Martin
authors.initials: M
authors.lastname: Burke
authors.forename: Andrew
authors.initials: A
authors.lastname: Kaplan
authors.forename: Lawrence
authors.initials: L
authors.lastname: Nair
authors.forename: Michael
authors.initials: M
authors.lastname: Belz
authors.forename: Charles
authors.initials: C
authors.lastname: Fuenzalida
authors.forename: Michael
authors.initials: M
authors.lastname: Gold
authors.forename: Charles
authors.initials: C
authors.lastname: Love
authors.forename: Arjun
authors.initials: A
authors.lastname: Sharma
authors.forename: Russell
authors.initials: R
authors.lastname: Silverman
authors.forename: Felix
authors.initials: F
authors.lastname: Sogade
authors.forename: Bruce
authors.initials: B
authors.lastname: Van Natta
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Wilkoff
mesh_terms: 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*