A cheap and painless set of tests developed in leading medical centers around the country promises to predict heart disease and stroke, and pinpoint the patients who really need aggressive therapy, far more accurately than do the traditional risk factors.
The new method includes a simple measurement of the difference in blood pressure between arms and ankles, and a noninvasive acoustic test that measures narrowing of the carotid arteries that carry blood to the brain.
Many patients with high cholesterol levels do not develop heart disease. Conversely, there are also many patients who develop silent heart disease without having any of the known risk factors, such as high cholesterol, smoking and diabetes.
The scientists who developed the new test hope that it will focus attention on patients in both categories who are most at risk.
"You don't necessarily have to apply aggressive treatment to everyone with bad risk factors," said Dr. Lewis Kuller, an epidemiologist at the University of Pittsburgh. Dr. Kuller helped develop the new method as part of an ongoing study of the emergence of cardiovascular disease in people 65 and older.
He predicted that the technique would prove most useful for people over 60, especially those with high cholesterol, and for people of any age whose doctors think they may need drugs to help lower blood cholesterol or triglycerides, another fatty component of the blood.
Without so much as a needle prick, the method indirectly measures the extent of hidden atherosclerosis, or clogging of the arteries, in people who have no outward symptoms of cardiovascular disease, such as chest pains.
The tests involve no dyes or injections and no pain or risk of injury. They can be performed by trained technicians with instruments that cost a few hundred dollars and a computer to calculate the results. Two of the tests involve the use of high-frequency sound waves to assess potential blockages in the arteries that feed the brain.
One of the most revealing tests, which measures the difference in blood pressure in the arms and the legs, could be put into widespread use almost immediately, Dr. Kuller said.
The findings will soon be published in the journal Circulation.