title: Are plasma natriuretic peptide levels influenced by automatic pacemaker algorithms for ventricular pacing minimization?
abstract: BACKGROUND
  Automatic atrioventricular search hysteresis (AVSH) is designed to reduce the cumulative percentage of potentially deleterious right ventricular apical pacing (VP%) in dual-chamber pacemakers. We investigated whether minimizing VP% by AVSH can, in turn, reduce ventricular wall stretching/stress, as assessed by plasma concentrations of the amino-terminal fragment of the pro-B-type natriuretic peptide (NT-proBNP).
  
  
  METHODS
  After dual-chamber pacemaker implantation in 81 patients (age: 69 ± 11 years; males: 55.6%), the fixed atrioventricular delay of 225 ms was programmed and AVSH was turned off for 1 month. The patients were thereafter randomly assigned to standard AVSH for 1 month, followed by an enhanced AVSH for another month, or vice versa. At the 1-, 2-, and 3-month follow-ups, VP% values were retrieved from the pacemaker memory, and venous blood samples were taken for NT-proBNP measurements.
  
  
  RESULTS
  Both standard and enhanced AVSH reduced the median VP% value from 38.5% (for the fixed atrioventricular delay) to 2.1% (P < 0.001). However, plasma NT-proBNP concentrations for the fixed atrioventricular delay (median, 253 pg/mL), standard AVSH (225 pg/mL), and enhanced AVSH (276 pg/mL) did not differ significantly on the intrapatient basis (paired Wilcoxon tests) between any pair of these modalities.
  
  
  CONCLUSIONS
  Minimizing ventricular pacing by AVSH during 1 month had no influence on plasma NT-proBNP levels (i.e., ventricular wall stretching/stress) compared with a constant, moderately prolonged atrioventricular delay.
authors.affiliation: Abteilung für Kardiologie, St Vincenz Krankenhaus, Limburg, Germany.
authors.forename: Joerg
authors.initials: J
authors.lastname: Kreuzer
authors.forename: Carsten
authors.initials: C
authors.lastname: Lennerz
authors.forename: Josef U
authors.initials: JU
authors.lastname: Dietl
authors.forename: Thomas
authors.initials: T
authors.lastname: Beier
authors.forename: Alexej
authors.initials: A
authors.lastname: Strauch
authors.forename: Verena
authors.initials: V
authors.lastname: Semmler
authors.forename: Haitham
authors.initials: H
authors.lastname: Badran
authors.forename: Bernhard
authors.initials: B
authors.lastname: Zrenner
authors.forename: Christof
authors.initials: C
authors.lastname: Kolb
mesh_terms: D000368:Aged; D000465:Algorithms; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D018592:Cross-Over Studies; D005260:Female; D006331:Heart Diseases / Q000097:blood* / Q000628:therapy*; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010138:Pacemaker, Artificial; D018709:Statistics, Nonparametric
chemical_list: D020097:Natriuretic Peptide, Brain