Chest pain patients who have abnormal coronary blood vessel function also have less responsive blood vessels in their fingertips, suggesting that a type of fingertip probe could become a useful screening tool, according to a new study in the Dec. 7, 2004 issue of the Journal of the American College of Cardiology.
“This test is a noninvasive and easy-to-perform technique to assess peripheral endothelial function that has the potential to become a valuable tool for cardiovascular risk stratification in daily clinical practice,” said Amir Lerman, M.D., F.A.C.C., at the Mayo Clinic in Rochester, Minn.
The test, reactive hyperemia peripheral arterial tonometry (RH-PAT), uses a probe that measures how the volume of a fingertip changes as blood pulses through it. After a baseline measurement, a blood pressure cuff is inflated to restrict blood flow in the arm for five minutes. The key measurement is how blood vessels in the fingertip respond to the initial rush of blood after the cuff is released.
The researchers, including lead author Piero O. Bonetti, M.D., studied 94 patients with chest pain who had been referred for coronary angiography testing. The patients did not have obstructive coronary artery disease, according to their angiography tests. However, the responsiveness of coronary blood vessel linings (endothelial function) was abnormal in 55 of the patients.
Normally, RH-PAT shows a distinct increase after blood flow is restored in the arms of subjects, but overall the fingertip blood vessels of the patients with abnormal endothelial function showed a more muted response.