Differences in circadian blood pressure between upper and lower extremity in aortic coarctation patients with and without postoperative pressure gradients.

The purpose of this study was to investigate possible circulatory differences between pre- and poststenotic vascular beds in postoperative coarctation patients with and without a residual pressure gradient during a physiologic decrease in circulatory activity. Simultaneous diurnal variations in blood pressure in the brachial and femoral arteries were recorded in 5 long-term postoperative coarctation patients with and in 5 without a pressure gradient. The patients were studied 6.5 to 8.5 years postoperatively with intraarterial blood pressure telemetry. Both groups of patients had a normal pressure decrease during the hours of sleep. A significant (p less than 0.05) increase, however, in brachial to femoral pressure gradients developed during the hours of sleep in patients with a positive gradient in contrast to patients without a gradient who had identical pressure profiles in both vascular beds. A significant positive correlation was found between changes in mean pressure gradient and upper extremity systolic pressure (r = 0.79, p less than 0.01). There was no difference between the 2 groups regarding pre- and postoperative pressures, preoperative gradients or age at surgery. Results suggest that normalization of prestenotic circadian vascular reactivity depends on complete relief of the gradient, and that upper extremity vascular abnormality may not be fully irreversible, even in older patients with coarctation.