Issue 210 Item 14 Screening For Coronary Artery Disease Needed for Asymptomatic

58.6% of the asymptomatic diabetics had abnormal scans for coronary artery disease. The results of a new study argue for the use of stress single-photon emission computed tomography (SPECT) in diabetic patients without clinically apparent coronary artery disease (CAD).

The value of screening stress tests in asymptomatic diabetic patients "remains controversial," Dr. Todd D. Miller and colleagues from the Mayo Clinic in Rochester, Minnesota note in the May issue of the American Heart Journal.
To further investigate, they retrospectively examined the yield of stress SPECT in asymptomatic diabetics (n=1738) compared with symptomatic diabetic patients (n=2998) as well as in asymptomatic nondiabetic patients (n=6215) and symptomatic nondiabetic patients (n=16,214). None of the patients had history of MI or coronary revascularization.

According to the team, 58.6% of the asymptomatic diabetics had abnormal scans, roughly equal to the percentage in symptomatic diabetics (59.5%) and higher than in asymptomatic nondiabetic and symptomatic nondiabetic patients (46.2% and 44.4%, respectively).

Moreover, 19.7% of asymptomatic diabetics had "high-risk" scans, a generally accepted indication to proceed to coronary angiography. High-risk scans were also obtained for 22.2% of symptomatic diabetics, 11.1% of asymptomatic nondiabetic, and 12.5% of symptomatic diabetic patients.

The finding of a high-risk scan in roughly one in five asymptomatic diabetic patients "suggests a potentially more widespread application of screening stress SPECT…to identify those with severe coronary artery disease," the authors conclude.

Dr. Gary V. Heller of Hartford Hospital in Connecticut and co-author Dr. Sachin M. Navare are hopeful that the ongoing Detection of Ischemia in Asymptomatic Diabetes (DIAD) trial will help clarify which asymptomatic diabetic patients would benefit the most from stress SPECT screening. Am Heart J 2004;147:753-755,890-896.