Regional Compliance of Brachial Artery and Saline Infusion in Patientswith Arteriosclerosis Obliterans

Simultaneous brachial artery pressure and blood flow measurements were made in 15 patients with arteriosclerosis of the lower limbs (AOLL) and in controls of the same age and sex. Blood flow was evaluated by a pulsed Doppler device with a doubletransducer probe. From analysis of the pressure-flow curves during diastole, regional arterial compliance (RAC) was determined by using as a model of the forearm arterial tree a system of tubes, each with a storage capacity, in series with the arteriolar resistance vessels. In AOLL patients, RAC was significantly reduced (102 ± 13 vs 173 ± 14-10 ml/mm Hg, p < 0.01), and systolic pressure was significantly increased. After saline infusion, systolic pressure continued to increase and arterial compliance, to decrease; brachial blood flow did not change. Study of the baroreflex sensitivity in AOLL patients under basal conditions indicated that a higher pulse pressure was required to obtain the same heart rate as in the controls. The study provided evidence that in AOLL patients1) compliance was reduced in the brachial artery (a regional circulation with no clinical evidence of arterial occlusion); 2) an increase in systolic pressure resulted from the decreased arterial compliance; and 3) saline infusion exaggerated the observed reduction in arterial compliance and increase in systolic pressure.