The use of unconventional screening tests, such as blood pressure taken at the ankle, may help spot adults at increased risk for heart attack who are not considered at high risk based on more "traditional" risk factors, according to research presented this week at the Society of Interventional Radiology's 34th annual meeting in San Diego.

A substantial number of heart attacks or sudden cardiac deaths occur in people not thought to be at high risk for these "events" by traditional risk factors like high blood pressure, high cholesterol, and cigarette smoking, "so identifying these people for prevention is important," Dr. Timothy Murphy of Rhode Island Hospital in Providence, explained during the conference.

Prior studies, Murphy added, have shown that an abnormally low blood pressure at the ankle, as well as high blood levels of the clotting factor fibrinogen and the inflammatory protein CRP, are associated with an increased risk of heart attack and death.

However, the prevalence of these novel risk factors among people not considered at high risk for heart events has not been reported.

To investigate, Murphy's team analyzed data on nearly 6300 middle-aged men and women who participated in the 1999-2004 National Health and Nutrition Examination Survey and who were free of a known history of diabetes, cardiovascular disease or stroke.

While 91 percent of these individuals were considered at low or intermediate risk of cardiovascular disease, according to traditional criteria alone, nearly 45 percent were found to have at least one of the three conditions: an abnormally low ankle blood pressure, elevated fibrinogen or elevated CRP.

The overall prevalence of low ankle blood pressure and high fibrinogen and CRP was 3.7 percent, 17.3 percent and 37.9 percent, respectively.

These findings, the investigators conclude, suggest that supplementing traditional heart disease risk factors with "inexpensive and readily available" markers like ankle blood pressure, fibrinogen and CRP, has potential to identify people in the low and intermediate risk category for intensive medical therapy to avoid heart attacks and stroke.