Digital Diagnosis of Coronary Artery Disease
A simple noninvasive test of blood flow may serve as a means to screen for early coronary atherosclerosis, according to a group of researchers from Mayo Clinic in Rochester, Minn., and Tufts University Medical Center in Boston.
Investigators evaluated the utility of reactive hyperemia–peripheral arterial tonometry (RH-PAT), a study of blood vessels in which circulation has been stopped and restored. Endothelial dysfunction is an early stage of coronary artery disease. Normally, when blood flow is disrupted and restored to a limb there is a particular “signature” that is indicative of vascular health.
The RH-PAT device was tested on 94 consecutive patients who were referred for coronary angiography. A blood pressure cuff was placed on one upper arm, while the other arm served as a control. Peripheral arterial tonometry probes were placed on one finger of each hand. The blood pressure cuff was inflated above systolic pressure for 5 minutes, then slowly deflated over a 10-minute period of time while the RH-PAT probe measured the amplitude of the pulse signals.
The average RH-PAT index was significantly higher among patients with normal coronary artery endothelial function. “This study demonstrates that patients with coronary microvascular endothelial dysfunction have a lower peripheral hyperemic endothelial response,” the authors report.
