NON-INVASIVE ECHO-DOPPLER DUPLEX MEASUREMENTS OF COMMON FEMORAL-ARTERY BLOOD-FLOW VARIABLES DURING SUPINE EXERCISE AND POST-OCCLUSIVE REACTIVE HYPEREMIA

Abstract

Noninvasive dynamic measurements of common femoral artery blood flow (CFBF) and stroke volume (CFSV) during supine exercise (SE) and staged postocclusive reactive hyperemia (PORH) in normal [human] subjects using an echo-Doppler duplex scanner (DS) would provide baseline hemodynamic data in the study of the peripheral circulation in resting, stressed and diseased conditions. Heart rate (HR), CFBF and CFSV were determined at rest (R), after 5 min of SE on an ergometer (30 rpm) at 30, 60 and 90-W loads and after a 3-min recovery. The same variables were also calculated after periods of 2-, 5- and 10-min thigh occlusions (> 240 mm Hg cuff pressure). Measurements of spatial average blood velocities and lumen diameters were used to calculate CFBF. Ankle pressure (AP) and brachial pressure (BP) were determined, and the ratio of systolic AP to systolic BP, the ankle index (Al), was calculated. As in vitro validation of the DS method was accomplished using a hydraulic model of CFBF (r = 0.98). Mean values for maximal CFBF following SE and PORH were 0.81 and 1.53 l/min, respectively. With SE, increases in CFBF and CFSV and decreases in Al were significant (P < 0.05) only at 60- and 90-W loads. Increases in CFBF and CFSV and decreases in AP and Al were significantly different (P < 0.05) from rest for the 3 occlusion durations and show a linear trend. Apparently, the DS method can noninvasively and quantitatively measure CFBF and CFSV at rest following SE and during PORH.