Abstract W P349: Prediction of Major Adverse Cardiovascular Events by Age-Normalized Carotid Intimal Medial Thickness.

Abstract

Background: Increases in carotid intimal medial thickness (CIMT), as measured by noninvasive ultrasonography, have been associated with increased risk of myocardial infarction and stroke. From 706 patients who had CIMT measured between 1995 and 2003 at the University of Virginia, we created age-specific quartiles of carotid thickness. Over a mean follow-up of 4.8 years, we found that bulb and internal but not common CIMT predicted the combined endpoint of myocardial infarction, stroke, and revascularization (Atherosclerosis 187:186, 2006). We now present the analysis as of 2012 for CIMT to predict major adverse cardiovascular events in a population of patients referred for carotid IMT measurement. Methods: From 1995-2012, 1427 patients had carotid IMT measured at the University of Virginia’s Preventive Cardiology practice. In 2012, we successfully contacted 1259 of these patients to determine clinical outcomes. The 1259 patients were entered into a database and odds ratios were calculated with logistic regression in SAS. Results: Over a mean follow-up period of 7.8 years (range, 1 to 16), 30 patients died and 66 had major adverse cardiovascular events (MACE): 17 patients had CV death/myocardial infarction; 20 required revascularization; and 29 had a stroke or transient ischemic attack. The highest quartile of bulb CIMT demonstrated an odds ratio for MACE of 7.2 (95% confidence interval, 3.0 to 18.6; P<0.001) when compared to the quartile with the lowest thickness (P<0.001 for trend). The highest quartile of internal CIMT demonstrated an odds ratio for MACE of 3.1 (95% confidence interval, 1.2 to 8.3; P=0.02) when compared to the quartile with the lowest thickness (P=0.009 for trend). Common carotid IMT did not significantly predict MACE (p=0.23). The highest quartile of bulb CIMT demonstrated an odds ratio for mortality of 3.4 (95% confidence interval, 1.03 to 11.2; P=0.044) when compared to the quartile with the lowest thickness (not significant for common or internal CIMT). Conclusions: Age-normalized measurement of bulb and internal but not common CIMT appear to predict which individuals would most benefit from aggressive risk-factor modification.