title: Permanent and atrial-synchronized ventricular stimulation for clinically stable patients with normal or impaired left ventricular systolic function.
abstract: BACKGROUND
  Ventricular desynchronization imposed by permanent dual-chamber ventricular pacing (VDD) may compromise ventricular function.
  
  
  METHODS
  We investigated the impact of background VDD pacing on the right and left ventricular (LV) function on 129 clinically stable outpatients (mean age 69 +/- 10) implanted chronically with a dual-chamber pacemaker or an automatic defibrillator by using echocardiographic techniques including tissue doppler imaging (TDI) and color M-mode (CMM) examinations, and B-type natriuretic peptide (BNP) measurements. Patients were divided into two groups of normal (n = 65) or impaired (n = 64) LV systolic function (ejection fraction 63 +/- 6% and 38 +/- 10%, respectively) according to clinical and echocardiographic criteria. Each patient group included two subgroups on the basis of the underlying permanent and atrial-synchronized heart rhythm: either intrinsic ventricular activation (IVA) or VDD pacing.
  
  
  RESULTS
  The BNP levels (mean, 95% CI) of patients with impaired LV systolic function were approximately threefold higher than those of patients with normal LV systolic function [189 (145-245) pg/mL vs 65 (50-85) pg/mL, P < 0.0001], but did not differ between subgroups of patients with IVA vs VDD pacing. By two-way analysis of variance and analysis of covariance, and after adjustment for age and gender, significant VDD pacing effects were found in terms of lower E/A ratio (P < 0.05) and increased LV end-systolic volume (P < 0.05). VDD pacing did not significantly affect the BNP levels and the LV filling pressures, as determined by the E/Ea and E/Vp ratios.
  
  
  CONCLUSIONS
  Long-term VDD pacing may not be harmful in clinically stable patients with normal or moderately reduced LV systolic function.
authors.affiliation: Department of Cardiology, Patras University Hospital, 26500 Rion, Patras, Greece. chil@otenet.gr
authors.forename: John A
authors.initials: JA
authors.lastname: Chiladakis
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Koutsogiannis
authors.forename: Andreas
authors.initials: A
authors.lastname: Kalogeropoulos
authors.forename: Fani
authors.initials: F
authors.lastname: Zagli
authors.forename: Ilias
authors.initials: I
authors.lastname: Sihlimiris
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Alexopoulos
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000150:complications / Q000000981:diagnostic imaging* / Q000517:prevention & control*; D002304:Cardiac Pacing, Artificial; D004554:Electric Countershock; D005260:Female; D006352:Heart Ventricles; D006801:Humans; D008297:Male; D016896:Treatment Outcome; D014463:Ultrasonography; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology / Q000517:prevention & control*