Independent Predictors of Cardiac Risk Evaluated
Coronary artery calcium scores may indicate long-term risk in patients with normal SPECT results
FRIDAY, Nov. 6 (HealthDay News) -- In patients with normal single-photon emission computed tomography (SPECT) results, a severe coronary artery calcium score (CACS) may predict high long-term cardiac risk, according to research published in the Nov. 10 issue of the Journal of the American College of Cardiology.
Su Min Chang, M.D., of the Methodist Hospital in Houston, and colleagues analyzed data from 1,126 individuals without history of coronary artery disease, most of whom were asymptomatic. Subjects underwent stress SPECT and received a CACS in close proximity, and were then followed for a median of 6.9 years.
The researchers found that individuals with a normal SPECT but a CACS above 400 were at higher risk of total cardiac events and all-cause mortality/myocardial infarction. Separation of the survival curves between those with minimal and severe CACS was at three years for total cardiac events and five years for death/myocardial infarction.
"The CACS and stress SPECT results are independent and complementary for predicting events. A severe CACS identifies a subgroup of subjects at high long-term risk even in the presence of a normal stress SPECT study," the authors conclude. "Our results support a strategy of adding CACS testing in patients with a normal SPECT result to identify those at high long-term risk for cardiac events. In these patients, earlier aggressive risk factor modification may deter further progression of coronary atherosclerosis and improve outcome."
The study was supported in part by HeartScan-Houston.