title: Comparison of stimulation sites within left ventricular veins on the acute hemodynamic effects of cardiac resynchronization therapy.
abstract: OBJECTIVE
  The purpose of this study was to study the acute hemodynamic effect of left ventricular (LV) stimulation sites within a coronary vein.
  
  
  BACKGROUND
  Access to LV stimulation sites for resynchronization therapy is achieved using specialized lead systems navigated through a coronary vein. The effects of stimulation in different coronary veins have been evaluated previously, but less is known about stimulation sites within a coronary vein.
  
  
  METHODS
  Twenty-four patients (New York Heart Association functional class II-IV, age 59 +/- 10 years, ejection fraction 21 +/- 7%, QRS 166 +/- 30 ms) were enrolled in the study. A novel over-the-wire lead system was used to access an anterior or lateral coronary vein. At each lead location, a randomized stimulation protocol was executed. Hemodynamic responses were evaluated using LV dP/dtmax.
  
  
  RESULTS
  The mean time to cannulate the coronary sinus and position the LV lead was 19 +/- 30 minutes and 17 +/- 18 minutes, respectively. Data from stimulation at two sites within a coronary vein were obtained in 19 patients (anterior vein 11; lateral vein 8). Of these patients, 14 (anterior vein 9; lateral vein 5) showed large improvement in dP/dtmax (22%-25% in anterior vein, 37%-40% in lateral vein). Overall, there were no group differences in hemodynamic effects among different stimulation sites within a coronary vein, although significant variability among sites was observed in individuals.
  
  
  CONCLUSIONS
  Resynchronization therapy through a coronary vein improves acute hemodynamic function of heart failure patients with LV conduction disorder. There were no significant differences between basal and apical pacing sites for this group.
authors.affiliation: Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina 29425, USA. goldmr@musc.edu
authors.forename: Michael R
authors.initials: MR
authors.lastname: Gold
authors.forename: Angelo
authors.initials: A
authors.lastname: Auricchio
authors.forename: John D
authors.initials: JD
authors.lastname: Hummel
authors.forename: Michael C
authors.initials: MC
authors.lastname: Giudici
authors.forename: Jiang
authors.initials: J
authors.lastname: Ding
authors.forename: Bruce
authors.initials: B
authors.lastname: Tockman
authors.forename: Julio
authors.initials: J
authors.lastname: Spinelli
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D003331:Coronary Vessels; D005260:Female; D006329:Heart Conduction System; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy*; D006352:Heart Ventricles / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*