title: Assessment of the optimal atrioventricular delay in dual chamber-paced patients by a portable scintillation probe (VEST).
abstract: BACKGROUND
  The optimal atrioventricular delay in dual-chamber pacing differs from patient to patient. The availability of a portable scintillation probe (VEST) enables noninvasive monitoring of left ventricular function.
  
  
  RESULTS
  Hemodynamic variations were measured in 10 patients with programmable DDD pacemakers. The ejection fraction, stroke volume, and diastolic and systolic volume were evaluated, programming six different atrioventricular delays ranging from 75 to 200 msec, to determine the most favorable atrioventricular delay. Comparing left ventricular ejection fraction (LVEF), stroke volume, and end-diastolic and end-systolic volume at each DVI mode with a preceding DVI setting of 75 msec, all parameters at 200 msec were statistically different from those at 100 msec. An increase of LVEF and stroke volume and a decrease of end-systolic volume was found. In only five patients a switch of VVI mode to the optimal DVI mode results in an increase of LVEF of more than 5%.
  
  
  CONCLUSIONS
  Our study stresses the importance of optimizing atrioventricular delay. The VEST system permits these measurements, increasing the accuracy of the determination of optimal atrioventricular delay, and appears to be valuable in the management of patients with cardiac dual-chamber pacemakers.
authors.affiliation: Department of Nuclear Medicine, University Hospital, Leuven, Belgium.
authors.forename: L
authors.initials: L
authors.lastname: Mortelmans
authors.forename: W
authors.initials: W
authors.lastname: Vanhecke
authors.forename: D
authors.initials: D
authors.lastname: Mertens
authors.forename: H
authors.initials: H
authors.lastname: Ector
authors.forename: C
authors.initials: C
authors.lastname: Timmermans
authors.forename: M
authors.initials: M
authors.lastname: De Roo
authors.forename: H
authors.initials: H
authors.lastname: De Geest
authors.forename: F
authors.initials: F
authors.lastname: Van de Werf
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods; D015637:Gated Blood-Pool Imaging / Q000295:instrumentation; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation; D010138:Pacemaker, Artificial; D016277:Ventricular Function, Left