The exercise pressor reflex and changes in radial arterial pressure and heart rate during walking in patients with arteriosclerosis obliterans

Abstract

Little is known about the time course and extent of the changes in radial arterial pressure and heart rate taking place in patients with arteriosclerosis obliterans during walking, as well their subtending mechanisms. For this reason the authors measured these variables in 23 patients with arteriosclerosis obliterans and in nine normal subjects (control group), during treadmill walking and several tests. In the patients a rapid and marked increase in radial arterial pressure was recorded during walking, whereas the same parameter either fell abruptly or persisted at elevated levels during recovery. This pattern markedly differed from that recorded in normal subjects, and it was mainly brought about by the activation of the exercise pressor reflex. The following findings suggested that the exercise pressor reflex was activated: the conditions required for activation of the reflex were present in our patients; the pressure changes observed during walking tightly paralleled the changes due to this reflex activation; the hypertensive response to walking was enhanced by increases in severity of disease and in walking speed and duration; the reflex activity persisted during recovery; and the pressure pattern during walking was reproduced by walking with arrested blood circulation to a lower limb. On the contrary, the behavior of heart rate was similar in patients and normal subjects both during walking and recovery because it was not influenced by the exercise pressor reflex.