Abstract 14571: Role of Microwave Radiometry in the Prediction of Multivessel Coronary Artery Disease
Background: Intima-media thickness (IMT) of carotid arteries has been used as a surrogate marker for the extent of coronary artery disease (CAD). Nevertheless, IMT does not provide information regarding the functional properties of carotid plaques. Microwave Radiometry (MR) allows in vivo noninvasive measurement of the internal temperatures of tissues reflecting inflammation. The aim of this study was to evaluate whether carotid artery MR measurements show similar predictive accuracy with established risk prediction models in multivessel CAD detection.
Methods: Consecutive patients (n=321) scheduled for coronary angiography were included in the study. IMTmax was assigned as the maximal IMT value of both carotid arteries. Respectively, ΔTmax by MR was assigned as the maximal value of the temperature differences (ΔT) of both arteries. Multivessel CAD was defined as the presence of ≥50% stenosis in at least two major epicardial vessels. We further compared with the use of c-statistic two risk prediction models: 1) traditional risk factors (TRF - sex, age, smoking, dyslipidemia, arterial hypertension, diabetes mellitus and family history) plus IMTmax, and 2) TRF plus ΔTmax.
Results: Of 321 patients, 49 (15.26%) did not have significant CAD, 112 (34.89) had 1-vessel CAD, 106 (33.02%) patients had 2-vessel CAD and 53 patients (16.83%) had 3-vessel CAD. ΔTmax was higher in patients with multivessel CAD in comparison to patients with 1-vessel or no CAD (1.05±0.49 vs 0.80±0.48oC, p<0.001). In multiple logistic regression analysis, ΔTmax was an independent predictor for the presence of multivessel CAD, when adjusted for TRF and IMTmax (p=0.012, OR: 1.98, 95% CI 1.16-3.37). The risk prediction models TRF+ΔTmax and TRF+IMTmax showed similar predictive capacity for the presence of multivessel CAD (c-statistic=0.715, 95% CI 0.663-0.764, p<0.01 vs 0.718, 95% CI 0.665-0.766, p<0.01, pdiffer. =0.9)
Conclusions: The predictive value of ΔTmax was comparable to that of IMTmax. Thus, both functional and structural characteristics of the carotid plaques can be used for the prediction of extensive coronary artery disease.
- © 2013 by American Heart Association, Inc.