Cheap stress test picks up coronary artery disease

A simple test can indicate whether people have significant coronary artery disease (S-CAD), researchers at the Washington Hospital Center have discovered.

To test cardiac respiratory stress response (RSR), the researchers use a Pulse Oximeter (PPG) to measure blood flow in a finger matched to paced breathing over a 90 second period. The PPG data are captured and analyzed using a proprietary algorithm.

The results found that patients with S-CAD had a much lower RSR compared to patients without – 6.7 percent versus 17.4 percent respectively.

The researchers tested their findings using Quantitive Coronary Angiography (QCA). The rest results are claimed to be highly accurate, with a sensitivity and specificity of 86 percent and 81 percent.

Ron Waksman, MD of the Division of Cardiology at Washington Hospital Center, said it’s difficult to detect significant coronary artery disease in patients at the doctors. Detection often involved a physical stress test, nuclear imaging and cardiac catheterisation.

He said: “The RSR test is simple and fast to perform in a doctor’s office without the need for significant expense and hardship to the patients, and results of the study support its accuracy to detect significant coronary artery disease.”

The test isn’t yet available in the US but is being used in over 25 cardiology clinics in the States.