Assessment of right and left ventricular volumes during upright exercise in normal men

Ventricular volumes were measured in 10 normal subjects by using two independent methods: the stroke volume was obtained by the Fick principle and the ejection fraction by multigated radionuclide angiography. Data were collected at rest in the supine and upright positions and during an upright exercise test, which included three levels of increasing severity. The left and right ventricular end-diastolic volumes (EDV) were maximal in the supine posture (respectively 183 and 260 ml); at rest both were significantly lower in the upright position (158 and 220 ml). At maximal exercise, the ventricular end-diastolic volumes were similar (left EDV=147 ml) or slightly lower (right EDV= 178 ml) than at rest in the upright position. During upright exercise, the end-systolic volumes (ESV) gradually decreased (P