Type 2 diabetics should have cardiac stress test

Contrary to current guidelines, “aggressive” efforts to detect coronary artery disease are worthwhile in asymptomatic patients with type 2 diabetes, even those with only one or no cardiovascular risk factors, a study conducted in Italy suggests.

Current coronary artery disease screening guidelines from the American Diabetes Association (ADA) recommend testing asymptomatic patients with diabetes and two or more additional risk factors. The guidelines state that asymptomatic diabetic patients with none or only one other coronary artery disease risk factor do not require cardiac testing, Dr. Roldano Scognamiglio and colleagues from the University of Padua Medical School note the American College of Cardiology.

In an attempt to “verify the effectiveness” of these guidelines, the researchers studied 1,899 asymptomatic type 2 diabetic patients 60 years old or younger.

They divided patients into two groups: group A included 1,121 patients with two or more coronary artery disease risk factors, and group B included 778 patients with no or only one coronary artery disease risk factor.

All of the subjects underwent cardiac stress tests and those with coronary defects in blood flow underwent angiography, which involves threading a catheter through a vein into the heart and then injecting dye into the coronary blood vessels. A series of X-rays are then taken to identify any blockages.

According to the team, the prevalence of abnormal stress test findings was similar in group A and group B (59.4 percent vs. 60 percent), as was the prevalence of significant coronary artery disease (64.6 percent vs. 65.5 percent).

This suggests that a “substantial number of asymptomatic diabetic patients with few risk factors might have occult coronary artery disease,” Scognamiglio and colleagues point out. “These patients might have been missed on the basis of current ADA guidelines.”

Moreover, “patients with coronary artery disease unmasked by an ‘aggressive’ approach had a more favorable angiographic anatomy of coronary vessels,” the team reports.

Patients in group B, they explain, were more apt to have one-vessel disease and less likely to have three-vessel disease, diffuse disease or occlusion. Based on the coronary anatomy picture, revascularization was not an option in 45 percent of patients with two or more risk factors.

The researchers note that in this study the screening criterion of two or more risk factors “did not help to identify asymptomatic patients with a higher percentage of coronary artery disease and is only related to a more severe coronary artery disease with unfavorable coronary anatomy.”

SOURCE: Journal of the American College of Cardiology, January 3, 2006.

Provided by ArmMed Media
Revision date: July 3, 2011
Last revised: by Janet A. Staessen, MD, PhD