Background: An important aspect of risk prediction is the apparent difference between calculated risk and true risk. Current risk predictor models are not sensitive enough to identify many subjects at risk for future events or to prevent overuse of expensive tests. The aim of this study was to determine the usefulness of carotid ultrasound for risk stratification in subjects undergoing elective coronary angiography.
Methods: A total of 253 individuals (men < or =55 years of age and women < or =65 years of age) who were scheduled for elective coronary angiography underwent carotid ultrasonography. Noncoronary atherosclerosis was defined based on a maximal intima-media thickness of > or =1.0 mm or the presence of focal plaque.
Results: Of the subjects, 236 completed all of the tests. The mean age was 51 +/- 8 years, and 58% were women and 42% men. Severe angiographic disease (> or =50%) was present in 72 subjects. Carotid atherosclerosis was present in 141 subjects. Use of the Framingham risk score classified 172 subjects as low risk. Carotid atherosclerosis was diagnosed in 57% of the low-risk group compared with 70% of the high-risk group (P = .122). Carotid atherosclerosis was associated with severe coronary angiographic disease (OR = 2.2, CI = 1.2 to 4.0).
Conclusion: Noncoronary atherosclerosis was associated with severe coronary disease as determined by angiography. Carotid atherosclerosis had a high negative predictive value in subjects with negative stress test results or risk-stratified as low risk. Noninvasive imaging by carotid ultrasonography for noncoronary atherosclerosis may be a good adjunct to clinical risk stratification for premature coronary heart disease.