Symptomatic hypotension during arm cycle ergometry exercise: a report of five cases

We report five cases of vasovagal and vasodepressor syncope or near-syncope that occurred during arm cycle ergometry. In each case, arm exercise in the seated position had been performed immediately after dynamic leg exercise. A likely mechanism involves a decrease in preload from venous pooling of blood in the lower extremities after leg exercise, and excessive stimulation of ventricular mechanoreceptors with resultant sympatho-inhibition and enhanced vagal tone. Four of the cases occurred early in the course of the exercise program, between the 8th and 10th sessions. The single case of true syncope occurred in a patient not receiving a beta-receptor blocking medication. No further events occurred when the exercise regimen was changed such that arm cycle ergometry was performed before leg exercise. We recommend that when arm ergometry is incorporated into an exercise program: (1) a cool-down period of exercise is performed after dynamic leg exercise, or (2) arm exercise is performed before dynamic leg exercise. These maneuvers may preclude the occurrence of symptomatic hypotension.