title: Invasive optimization of cardiac resynchronization therapy: role of sequential biventricular and left ventricular pacing.
abstract: BACKGROUND
  Aim of this invasive study was to characterize and quantify changes in left ventricular (LV) systolic function due to sequential biventricular pacing (BV) as compared to right atrial triggered simultaneous BV (BV(0)), LV, and right ventricular (RV) pacing in patients with congestive heart failure (CHF).
  
  
  METHODS
  In 22 CHF patients, all in sinus rhythm, temporary multisite pacing was performed prior to implantation of a permanent system. LV systolic function was evaluated invasively by the maximum rate of LV pressure increase (dP/dt(max)). Sequential BV pacing was performed with preactivation of either ventricle at 20-80 ms.
  
  
  RESULTS
  In comparison to RV pacing, LV and BV(0) pacing increased dP/dt(max) by 33.9 +/- 19.3% and 34.0 +/- 22.6%, respectively (P < 0.001). In 9 patients, optimized sequential BV pacing further improved dP/dt(max) by 8.5 +/- 4.8% compared to BV(0) (range 3.3-17.1, P < 0.05). In 10 patients exhibiting a PR interval < or =200 ms, LV pacing was either superior (n = 6) or equal to BV(0) pacing (n = 4). In these 10 patients, LV pacing yielded a 7.4 +/- 8.0% higher dP/dt(max) than BV(0) pacing (P < 0.05).
  
  
  CONCLUSIONS
  Using sequential BV pacing, generally with LV preactivation, moderate improvements in LV systolic function can be achieved in selected patients. Baseline PR interval may aid in the selection of the optimum cardiac resynchronization therapy (CRT) mode, favoring LV pacing in patients with a PR interval < or =200 ms.
authors.affiliation: Department of Cardiology, Kerckhoff-Klinik, Bad Nauheim, Germany. k.kurzidim@kerckhoff-klinik.de
authors.forename: Klaus
authors.initials: K
authors.lastname: Kurzidim
authors.forename: Heinrich
authors.initials: H
authors.lastname: Reinke
authors.forename: Johannes
authors.initials: J
authors.lastname: Sperzel
authors.forename: Hans Jürgen
authors.initials: HJ
authors.lastname: Schneider
authors.forename: Dejan
authors.initials: D
authors.lastname: Danilovic
authors.forename: Gregor
authors.initials: G
authors.lastname: Siemon
authors.forename: Thomas
authors.initials: T
authors.lastname: Neumann
authors.forename: Christian W
authors.initials: CW
authors.lastname: Hamm
authors.forename: Heinz-Friedrich
authors.initials: HF
authors.lastname: Pitschner
mesh_terms: D000368:Aged; D006328:Cardiac Catheterization; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D016009:Chi-Square Distribution; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology / Q000628:therapy*