title: Implications of right ventricular septal pacing for medium-term prognosis: Propensity-matched analysis.
abstract: BACKGROUND
  The effect of right ventricular (RV) septal pacing as opposed to RV apical pacing on prognosis in patients undergoing pacemaker implantation remains controversial. This study was performed to examine the clinical efficacy of RV septal pacing in a large cohort with medium-term follow-up and propensity-matched analysis.
  
  
  METHODS
  A total of 982 consecutive patients with first pacemaker implantation between 2008 and 2013 at two centers in Japan (51.4% male, age 76.1±10.6years, 64.3% septal pacing, 94% preserved ejection fraction [EF]) were enrolled. Propensity matching successfully matched 446 patients into RV septal and apical pacing groups. The primary endpoint, a combination of all-cause death and hospitalization due to heart failure, was compared between the two groups.
  
  
  RESULTS
  In the propensity-matched cohort, the primary endpoint was observed in 61 patients (13.7%) over a median follow-up period of 2.1years (interquartile range, 1.1-3.5years). The effects of septal pacing on prognosis were not statistically significant (hazard ratio [HR]=1.10, 95% confidence interval [CI]=0.60-2.04, P=0.752). No significant benefit of septal pacing was observed on all-cause death (HR=1.86, 95%CI=0.74-4.66, P=0.187) and heart failure hospitalization (HR=0.93, 95%CI=0.44-1.98, P=0.847) when assessed separately.
  
  
  CONCLUSIONS
  Septal pacing did not show medium-term advantages in prognosis in this large-scale retrospective cohort study with propensity matching of patients with predominantly preserved EF.
authors.affiliation: Department of Cardiology, Kameda Medical Center, 929 Higashi-cho, Kamogawa, Chiba 296-8602, Japan. Electronic address: akmizukami@gmail.com.
authors.forename: Akira
authors.initials: A
authors.lastname: Mizukami
authors.affiliation: Department of Cardiology, Kameda Medical Center, 929 Higashi-cho, Kamogawa, Chiba 296-8602, Japan.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Matsue
authors.affiliation: Cardiovascular Division, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Naruse
authors.affiliation: Department of Cardiovascular Medicine, Yokohama Rosai Hospital, 3211 Kozukue-cho, Kohoku-Ku, Yokohama, Kanagawa 222-0036, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Kowase
authors.affiliation: Department of Cardiovascular Medicine, Yokohama Rosai Hospital, 3211 Kozukue-cho, Kohoku-Ku, Yokohama, Kanagawa 222-0036, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kurosaki
authors.affiliation: Department of Cardiology, Kameda Medical Center, 929 Higashi-cho, Kamogawa, Chiba 296-8602, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Department of Cardiology, Kameda Medical Center, 929 Higashi-cho, Kamogawa, Chiba 296-8602, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Matsumura
authors.affiliation: Cardiovascular Division, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Nogami
authors.affiliation: Cardiovascular Division, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Aonuma
authors.affiliation: Department of Cardiology, Kameda Medical Center, 929 Higashi-cho, Kamogawa, Chiba 296-8602, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hashimoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects / Q000379:methods / Q000401:mortality; D005260:Female; D006333:Heart Failure / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D006346:Heart Septum / Q000503:physiopathology; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D010138:Pacemaker, Artificial / Q000009:adverse effects; D011379:Prognosis; D057216:Propensity Score; D012189:Retrospective Studies; D013318:Stroke Volume; D016019:Survival Analysis
keywords: Heart failure; Mortality; Prognosis; Propensity matching; RV non-apical pacing; RV septal pacing