title: Right ventricular septal pacing in patients with right bundle branch block.
abstract: BACKGROUND
  Cardiac resynchronization therapy (CRT) has been shown to improve left ventricular (LV) function and exercise performance in patients with left bundle branch block. Patients with right bundle branch block (RBBB) do not have a similar positive response to standard CRT. We hypothesized that single site pacing of the right ventricular septum (RVS) near the proximal right bundle could restore more normal activation of the LV in RBBB patients.
  
  
  METHODS
  78 consecutive patients (56 M, 22 F) with baseline RBBB underwent pacemaker or ICD implantation. Leads were placed in the right atrium and RVS.
  
  
  RESULTS
  Baseline QRS duration was 120-220 ms (mean QRSd = 147 ms). At the optimal AV delay, the fused QRSd was 56-160 ms (mean QRSd = 112 ms). The mean decrease in QRSd was 34 ± 20.4 ms (p<0.001).
  
  
  CONCLUSIONS
  RVS pacing in patients with RBBB resulted in a marked decrease in QRS duration and often normalized the ECG.
authors.affiliation: Division of Cardiology, University of Iowa Hospitals, Iowa City, Iowa. Electronic address: michael-c-giudici@uiowa.edu.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Giudici
authors.affiliation: Division of Cardiology, University of Iowa Hospitals, Iowa City, Iowa.
authors.forename: Basil
authors.initials: B
authors.lastname: Abu-El-Haija
authors.affiliation: Division of Cardiology, University of Iowa Hospitals, Iowa City, Iowa.
authors.forename: Phillip E
authors.initials: PE
authors.lastname: Schrumpf
authors.affiliation: Division of Cardiology, University of Iowa Hospitals, Iowa City, Iowa.
authors.forename: Prashant D
authors.initials: PD
authors.lastname: Bhave
authors.affiliation: Division of Cardiology, University of Iowa Hospitals, Iowa City, Iowa.
authors.forename: Belal
authors.initials: B
authors.lastname: Al Khiami
authors.affiliation: Florida Arrhythmia Institute, Tampa, Florida.
authors.forename: Serge S
authors.initials: SS
authors.lastname: Barold
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002037:Bundle-Branch Block / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*; D054088:Ventricular Septum
keywords: Cardiac resynchronization; Right bundle branch block; Right ventricular septal pacing