ATLANTA, Ga. (October 11, 2010)—While most people know about blood tests for cholesterol and other indicators that measure a person’s risk for developing heart disease, Piedmont Heart Institute played a key role in a study that validates the first and only blood test that can diagnose whether a non-diabetic patient's symptoms are due to obstructive coronary artery disease.
The Piedmont Heart Institute provided expertise and enrolled more than 100 patients for the PREDICT study which will be published in the October 5th issue of the highly respected Annals of Internal Medicine, the journal of the American College of Physicians. Szilard Voros, M.D., cardiologist and chief scientific officer at the Piedmont Heart Institute played a crucial role in the design, development and oversight of the study and is one of the co-authors and member of the PREDICT study steering committee.
The blood test, which measures gene expression, also is the first sex-specific test for coronary artery disease that accounts for critical biological differences between men and women. The test involves a simple blood draw that routinely takes place in physician offices across the country. While not yet covered by all insurance plans, the blood test isn’t invasive and doesn’t involve radiation and other imaging agents that are currently used to diagnose obstructive coronary artery disease.
“This advancement could significantly cut down the number of angiograms and nuclear tests performed on patients each year,” said Dr. Voros. “The new blood test could help clinicians confidently identify which of their stable symptomatic patients are likely to need further assessment for obstructive coronary artery disease, averting the need for unnecessary invasive procedures, such as angiograms, and nuclear radiation.”
Obstructive coronary artery disease, which results from fatty cholesterol buildup inside the arteries that feed the heart muscle, is often difficult to diagnose. Patients complaining of pains suggestive of coronary artery disease often undergo stress tests following an initial evaluation. If these test results prove uncertain, physicians often order an angiogram (an invasive procedure that involves radiation) to check for blocked arteries.
A recent American College of Cardiology study published in the New England Journal of Medicine found that nearly 62 percent of patients who underwent elective invasive angiographic procedures were found to have no obstructive coronary artery blockage. The study concluded that better methods are needed to determine which patients should have elective angiograms.
“Finding better ways to predict and prevent heart attacks before they happen is a goal and a passion of Dr. Voros and the Piedmont Heart Institute Physicians,” said William Knopf, M.D., chief operating officer of Piedmont Heart Institute and vice president of Cardiovascular Services at Piedmont Hospital. “We are proud that this study has received the recognition it deserves and can help all physicians in their work to save lives.”
The two-year study, led by principal investigator Eric Topol, M.D, director of the Scripps Translational Science Institute, analyzed results from a gene expression test that looked at cells in the blood of 1,343 non-diabetic patients from 39 U.S. clinical sites and then compared them to outcomes from their angiograms.
The Piedmont Heart Institute is also an integral part of the next study, COMPASS, involving this gene expression test which will be comparing the diagnostic accuracy of this gene expression test to nuclear stress testing.
In addition to the Piedmont Heart Institute and Scripps Health, the study was co-authored by scientists from leading research organizations across the United States, including Duke University; Vanderbilt Heart and Vascular Institute; Minneapolis Heart Institute Foundation; Washington Hospital Center; Oklahoma Cardiovascular Research Foundation; Cleveland Clinic; and Cardiovascular Research Foundation of New York. The study was funded and co-authored by CardioDx, a cardiovascular genomic diagnostic company. CardioDx named the test Corus CAD which is now commercially available for $1,200 in a patient sample kit that includes everything needed for blood collection and express delivery to the company’s CLIA-certified laboratory in Palo Alto, Ca.