title: Acute effect of DDD versus VVI pacing on arterial distensibility.
abstract: Pulse wave velocity (PWV) is a new technique and frequently used today to determine the elastic distensibility of great arteries. Increased arterial stiffness and PWV have been proposed as possible mechanisms in the initiation and/or progression and/or complications of atherosclerosis and cardiovascular disease. We evaluated the acute effect of two frequently used pacing modes (DDD vs. VVI) on arterial distensibility using PWV.
  
  
  METHODS
  Seventeen patients (age, 56 +/- 14 years) implanted with DDD pacemakers were included in the study. All patients were pacemaker dependent and continuously paced at the programmed rate. PWV was measured first in DDD mode, and then the mode was switched to VVI, and PWV was measured again at the same programmed heart rate as in the DDD mode.
  
  
  RESULTS
  Although systolic blood pressure significantly decreased from 129 +/- 18 to 119 +/- 16 mm Hg (p = 0.001) after switching the mode from DDD to VVI, diastolic blood pressure (81 +/- 12 vs. 80 +/- 13 mm Hg; p = 0.38) did not change. In addition, PWV significantly increased from 11 +/- 2.46 m/s in DDD mode to 11.29 +/- 2.43 m/s (p = 0.01) after having been programmed to VVI mode.
  
  
  CONCLUSIONS
  Our results suggest that VVI pacing increases PWV, and therefore decreases arterial distensibility, and thus may contribute to the development and progression of atherosclerosis.
authors.affiliation: Department of Cardiology, Trakya University School of Medicine, Edirne, Turkey. altun@medscape.com
authors.forename: Armagan
authors.initials: A
authors.lastname: Altun
authors.forename: Okan
authors.initials: O
authors.lastname: Erdogan
authors.forename: Mustafa
authors.initials: M
authors.lastname: Yildiz
mesh_terms: D000328:Adult; D000368:Aged; D001011:Aorta / Q000502:physiology*; D001161:Arteriosclerosis / Q000209:etiology / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects*; D018450:Disease Progression; D004548:Elasticity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014664:Vasodilation / Q000502:physiology*