Peak exercise left ventricular performance in normal subjects and in athletes assessed by first-pass radionuclide angiography.
The role of Frank-Starling law of the heart in determining the increase in cardiac output during exercise in humans is still controversial (e.g., the mechanisms responsible for the enhancement of left ventricular [LV] filling during the shortened diastolic interval). Ten weight lifters, 12 swimmers and 12 sedentary subjects who underwent maximal upright bicycle exercise testing were studied. First-pass radionuclide angiography was performed both at rest and at peak exercise using a multicrystal gamma camera. Compared with resting values, heart rate and cardiac index at peak exercise increased by 101 +/- 16 beats/min (p less than 0.001) and 6.7 +/- 2.8 liters/min/m2 (p less than 0.001) in weight lifters, by 96 +/- 9 beats/min (p less than 0.001) and 9.5 +/- 2 liters/min/m2 (p less than 0.001) in swimmers, and by 103 +/- 9 beats/min (p less than 0.001) and 7.3 +/- 1.8 liters/min/m2 (p less than 0.001) in sedentary subjects. Stroke volume increased by 20.5 +/- 9.8 ml/m2 (p less than 0.001) in swimmers only. End-diastolic volume at peak exercise did not change in weight lifters and in swimmers; it decreased by 8.2 +/- 8.6 ml/m2 (p less than 0.01) in sedentary subjects. A significant correlation was found between the decrease in end-systolic volume and the increase in peak rapid filling rate at peak exercise in all 3 groups (r = 0.65, p less than 0.05 in weight lifters; r = 0.59, p less than 0.05 in swimmers; r = 0.67, p less than 0.05 in sedentary subjects.(ABSTRACT TRUNCATED AT 250 WORDS)
Tomai
F
F
Dipartimento di Medicina Interna, Università Tor Vergata, Roma, Italia.
Ciavolella
M
M
Gaspardone
A
A
De Fazio
A
A
Basso
E G
EG
Giannitti
C
C
Scali
D
D
Versaci
F
F
Crea
F
F
Gioffrè
P A
PA
D000328:Adult; D017023:Coronary Angiography / Q000379:methods*; D015444:Exercise / Q000502:physiology*; D006321:Heart / Q000000981:diagnostic imaging; D006439:Hemodynamics; D006801:Humans; D008297:Male; D011877:Radionuclide Imaging; D013177:Sports; D014655:Vascular Resistance; D016277:Ventricular Function, Left / Q000502:physiology*