title: Cardiac index and exercise during VDD/DDD versus VVIR pacing in children. The effects of atrioventricular delay.
abstract: Twelve children with a VDD/DDD pacemaker during 100, 125, 150, 200 ms atrioventricular delays and VVIR pacing, cardiac index was measured at rest and evaluated by endurance time during exercise stress test. The optimal atrioventricular delay, which provides highest cardiac index, was 100 ms in three, 125 ms in two, and 150 ms in four and 200 ms in three patients. VDD/DDD pacing with different atrioventricular intervals resulted in a significantly higher cardiac index (6.70 +/- 3.06, 6.49 +/- 2.51, 6.15 +/- 2.35, 6.37 +/- 2.69 l/min/m(2), respectively) than VVIR pacing (5.25 +/- 2.39 l/min/m(2)) at the rest. However, endurance times to treadmill exercise were similar in both the optimal atrioventricular delay (21.6 +/- 3.7 min) and VVIR mode (22.4 +/- 3.4 min) (p > 0.05).
authors.affiliation: Department of Pediatric Cardiology, Hacettepe University, Faculty of Medicine, Ankara, Turkey. baspinar@gantep.edu.tr
authors.forename: Osman
authors.initials: O
authors.lastname: Baspinar
authors.forename: Alpay
authors.initials: A
authors.lastname: Celiker
authors.forename: Tevfik
authors.initials: T
authors.lastname: Karagoz
mesh_terms: D000293:Adolescent; D000328:Adult; D001830:Body Surface Area; D002302:Cardiac Output / Q000502:physiology*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D002648:Child; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006327:Heart Block / Q000628:therapy*; D006329:Heart Conduction System / Q000502:physiology; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D013997:Time Factors