Early thoracic aorta enlargement in asymptomatic individuals at risk for cardiovascular disease: determinant factors and clinical implication

Objectives We analyzed, in above-average risk asymptomatic individuals, the factors determining early thoracic aorta enlargement. Methods Ascending aortic diameter (AAD) was measured with noncontrast multidetector computed tomography in 345 participants (mean age 56 years; 78% men) without cardiovascular disease. We analyzed the associations of AAD with risk factors and Framingham risk score (FRS), multidetector computed tomography-assessed coronary artery calcium (CAC), and ultrasound interrogation of plaque presence at five sites (right and left carotid arteries, right and left femoral arteries, and abdominal aorta), the number of diseased sites with presence of plaque being counted from 0 to 5. Results AAD was positively associated with age (P<0.001), male sex (P<0.01), body surface area (BSA; P<0.001), hypertension (P<0.001), systolic and diastolic blood pressures in individuals without antihypertensive medication (P<0.05, P<0.01), and FRS (P<0.001). AAD was positively associated with CAC score after adjusting for age, sex, and BSA (P<0001) or for FRS and BSA (P<0.001). AAD was higher in the presence of three, four, or five than in the presence of no, one, or two diseased sites with plaque, after adjusting for age, sex, and BSA (P<0.05) or for FRS and BSA (P<0.001). When participants were divided into subsets by AAD tertiles and by number of sites with plaque, FRS and CAC score were greatest in individuals with AAD top tertile and 3-5 sites with plaque and lowest in those with AAD bottom tertile and 0-2 sites with plaque (P<0.001). Conclusion These findings suggest that thoracic ascending aorta dilatation is related to hypertension and represents a part of a generalized atherosclerotic process of the entire vasculature. (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.