Abstract 13615: Clinically Graded Carotid Artery Stenosis and Incident Myocardial Infarction: The Multi-Ethnic Study of Atherosclerosis.
Background: Carotid and coronary atherosclerosis are associated in imaging and autopsy studies. We evaluated the utility of clinically grading the severity of carotid artery lesions seen on carotid ultrasound for predicting incident myocardial infarction (MI). Materials and
Methods: Carotid ultrasound examinations were performed in 6389 participants (mean age 69.1 years) in the Multi-Ethnic Study of Atherosclerosis (MESA), a multi-ethnic cohort of Caucasian, African-American, Hispanic and Chinese participants free of cardiovascular disease at baseline. Incident MI was determined during follow-up (mean 6.1 years). Internal carotid artery lesions were graded as absent, 1-24%, 25-49% and ≥ 50% diameter narrowing and far wall mean common carotid intima-media thickness (IMT) was measured. Multivariable Cox proportional hazards models were used to estimate hazard risk ratios (HR) adjusting for traditional cardiovascular risk factors, race/ethnicity, common carotid IMT, income and education.
Results: Incident MI occurred in 139 participants. Unadjusted event rates increased with increasing level of stenosis. In multivariable Cox proportional models, compared to the group with no arterial lesion, the association between % narrowing and incident MI was progressive: HR 1.68 [95% CI: 1.08,2.62] for 1-24%, 2.17 [95% CI: 1.31,3.59] for 25-49%, and 4.09 [95% CI: 1.88,8.90] for ≥ 50% lesions.
Conclusions: In our population, the association between clinically graded severity of carotid artery stenosis and incident MI is significant and progressive. Clinical grading of carotid artery disease may contribute to the risk assessment of asymptomatic individuals at risk for coronary artery disease.
- © 2011 by American Heart Association, Inc.