De Motu Arteriarum

Abstract

See related article, pp 1145–1150 In reductionist times, it is refreshing to appreciate the creativity of apparently “simple” technical approaches coupled with clever experimental design. The study of Jiang et al1 evokes Harvey2 in its manipulation of human vascular behavior using a “ligature,” coupled with careful visual appraisal, to examine the impact of pressure on artery diameter responses. They modified a technique introduced by Celermajer et al3 involving inflation of a pneumatic cuff placed around the forearm to high pressure (for ≈5 minutes) to induce distal limb ischemia. Cuff deflation is associated with a large increase in blood flow through the upstream radial or brachial artery,4 which, in turn, induces a “flow-mediated” dilation (FMD).3 This, in turn, has been attributed to the release of vasodilator paracrines such as NO from the endothelium, as a consequence of shear stress–mediated signal transduction.5 The FMD test has become a popular noninvasive test of endothelial function, in part because it predicts future cardiovascular events.6,7 The kinetics of the vasodilator response after cuff deflation in the FMD test have always been quizzical in that the peak blood …