Got heart disease? The answer may be in your fingertips

A noninvasive fingertip test can identify patients with the earliest stages of heart disease and may prove cost-effective as a screening test, according to the findings of a Mayo Clinic study published this week in the Journal of American College of Cardiology.

“Atherosclerosis tends to affect all of the blood vessels in the body, and is not just limited to the arteries of the heart,” explains Amir Lerman, M.D., the Mayo Clinic cardiologist who led the study. “We expected patients with an abnormal result in the fingertip test to also have disease starting in their coronary arteries. We found a strong correlation, and that the fingertip test was very sensitive in identifying patients with early heart disease.”

The study compared results of both invasive and noninvasive tests of dysfunction in a layer of cells called the endothelium that lines the blood vessels. The endothelium protects vessel walls from injury and helps modulate their expansion and contraction to maintain appropriate blood flow and blood pressure. Endothelial dysfunction is the earliest measure of functional abnormality in the blood vessels, so coronary endothelial dysfunction signals the beginning stages of atherosclerosis and heart disease. Researchers are examining how this blood vessel dysfunction in the body’s extremities, such as the fingers, can be a sign that the same problem exists in the heart.

In the study, researchers investigated the value of reactive hyperemia peripheral arterial tonometry (RH-PAT) by using a fingertip probe to assess the relationship between dysfunction in the heart region and dysfunction in extremities.

Through invasive testing in the catheterization lab of the 94 patients participating, the team found 55 had coronary endothelial dysfunction. By comparing these results against RH-PAT, the researchers found a threshold value for the fingertip test that would have identified the majority of the patients with early heart disease.

The study findings indicate a potential role for RH-PAT as a test to identify individuals like this prior to an invasive procedure such as angiogram, or perhaps even to find who need more aggressive treatment to slow or stop the progression of cardiovascular disease.

“In this group of patients with chest pain, the noninvasive test was very sensitive in identifying those with early heart disease,” says Dr. Lerman. “The next step is to extend the research to broader populations of patients who may not yet have symptoms. Because this is a simple test that takes only about 20 minutes, we hope it could become another screening tool to help us identify and more effectively treat patients with heart disease.”