title: Comparison of temporary bifocal right ventricular pacing and biventricular pacing for heart failure: evaluation by tissue Doppler imaging.
abstract: BACKGROUND
  The complications and limitations of biventricular pacing largely relate to left ventricular (LV) pacing. An alternative approach was tested of simultaneously pacing the right ventricular (RV) apex and outflow tract (RVOT) or using bifocal right ventricular pacing (BRVP) to provide cardiac resynchronisation.
  
  
  METHODS
  21 consecutive patients with heart failure and severely impaired left ventricular function were studied. Ejection fraction and tissue Doppler data were collected at baseline, during BRVP, and during biventricular pacing, using a temporary pacing protocol.
  
  
  RESULTS
  BRVP was achieved in all patients without complication. BRVP significantly reduced mean baseline intra-LV, inter-LV-RV, and global mechanical dyssynchrony from (mean (SD)) 71 (35) to 44 (18) ms, p = 0.003; 86 (42) to 57 (33) ms, p = 0.029; and 157 (67) to 101 (42) ms, p = 0.005, respectively. It increased the ejection fraction from 21 (8)% to 29 (7)%, p = 0.002. Compared with BRVP, reductions in intra-LV, inter-LV-RV, and global mechanical dyssynchrony were superior with biventricular pacing (31 (12) ms, p = 0.014; 36 (27) ms, p = 0.008; and 67 (34) ms, p = 0.01 compared with BRVP, respectively); improvements in ejection fraction were similar (26 (9)%, NS).
  
  
  CONCLUSIONS
  In patients with heart failure, superior mechanical resynchronisation is achieved with biventricular pacing compared with BRVP. BRVP may be useful when left ventricular lead placement is not possible.
authors.affiliation: Waller Cardiac Unit, International Centre for Circulatory Health, St Mary's Hospital and Imperial College of Medicine, London, UK.
authors.forename: R E
authors.initials: RE
authors.lastname: Lane
authors.forename: J
authors.initials: J
authors.lastname: Mayet
authors.forename: N S
authors.initials: NS
authors.lastname: Peters
authors.forename: D W
authors.initials: DW
authors.lastname: Davies
authors.forename: A W C
authors.initials: AW
authors.lastname: Chow
mesh_terms: D002304:Cardiac Pacing, Artificial / Q000379:methods*; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013318:Stroke Volume / Q000502:physiology