title: Acute hemodynamic effects of right and left ventricular lead positions during the implantation of cardiac resynchronization therapy defibrillators.
abstract: BACKGROUND
  To evaluate the acute hemodynamic effects of different right (RV) and left ventricular (LV) pacing sites in patients undergoing the implantation of a cardiac resynchronization therapy defibrillator (CRT-D).
  
  
  METHODS
  Stroke volume index (SVI), assessed via pulse contour analysis, and dp/dt max, obtained in the abdominal aorta, were analyzed in 21 patients with New York Heart Association class III heart failure and left bundle branch block (mean ejection fraction of 24 ± 6%), scheduled for CRT-D implantation under general anesthesia. We compared the hemodynamic effects of RV apical (A), RV septal (B), and biventricular pacing using the worst (lowest SVI; C) and best (highest SVI; D) coronary sinus lead positions.
  
  
  RESULTS
  Mean arterial pressure, SVI, and dp/dt max did not differ significantly between RV apical and septal pacing. Dp/dt max and SVI increased significantly during biventricular pacing (dp/dt max: B, 588 ± 160 mmHg/s; C, 651 ± 218 mmHg/s, P = 0.03 vs B; D, 690 ± 220 mmHg/s, P = 0.02 vs C; SVI: B, 33.6 ± 5.5 mL/m², C, 34.8 ± 6.1 mL/m², P = 0.08 vs B, D 36.0 ± 6.0 mL/m², P < 0.001 vs C). The best hemodynamic response was associated with lateral or inferior lead positions in 15 patients. Other LV lead positions were most effective in six patients.
  
  
  CONCLUSIONS
  The optimal LV lead position varies significantly among patients and should be individually determined during CRT-D implantation. The impact of the RV stimulation site in patients with intraventricular conduction delay, undergoing CRT-D implantation, has to be investigated in further studies.
authors.affiliation: Departments of Rhythmology, Heart Center Bad Krozingen, Bad Krozingen, Germany.
authors.forename: Jochem
authors.initials: J
authors.lastname: Stockinger
authors.forename: Klaus
authors.initials: K
authors.lastname: Staier
authors.forename: Jochen
authors.initials: J
authors.lastname: Schiebeling-Römer
authors.forename: Cornelius
authors.initials: C
authors.lastname: Keyl
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure; D058409:Cardiac Resynchronization Therapy Devices; D003326:Coronary Circulation; D017147:Defibrillators, Implantable; D004567:Electrodes, Implanted; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006333:Heart Failure / Q000503:physiopathology* / Q000517:prevention & control*; D006352:Heart Ventricles / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume; D016896:Treatment Outcome