Relation of aortic wall thickness and distensibility to cardiovascular risk factors (from the Multi-Ethnic Study of Atherosclerosis [MESA])

Abstract

To determine the relation between aortic wall thickness (WT) and aortic distensibility (AD) with traditional cardiovascular risk factors in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort, 1,053 participants in MESA who underwent cardiac magnetic resonance imaging were consecutively selected for the measurement of aortic WT and AD. Double inversion-recovery fast spin-echo images of the thoracic aorta were obtained to measure average and maximum WT. AD was measured at the same level using a gradient-echo cine sequence. Average and maximum WT were positively correlated with increasing age, and AD was inversely related to age (p <0.01). Compared with normotensive participants, those with hypertension had significantly greater mean average WT (2.45 vs 2.23 mm, p <0.01) and maximum WT (3.61 vs 3.41 mm, p <0.01) and lower AD (0.15 vs 0.2 mm Hg(-1), p <0.01). In multiple regression analysis, older age and hypertension were significantly associated with higher mean average WT, while older age, male gender, and higher blood pressure were associated with higher mean maximum WT. AD was inversely related to older age, hypertension, current smoking, African American ethnicity, and lower high-density lipoprotein cholesterol level. In conclusion, in the MESA cohort, older age and higher blood pressure were associated with higher aortic WT and lower AD. Decreased AD was further associated with current smoking, African American ethnicity, and higher high-density lipoprotein cholesterol level.

Figure 1

Average and maximum aortic wall thickness (scale on the left) and aortic distensibility (scale on the right) cross different age categories (p <0.01).

Figure 2

Normal cross-section of the descending aortic wall in an 81-year old male without history of diabetes and hypertension, and no indication of atherosclerotic plaque (A). Descending aortic wall of a 67-year old male with history of hypertension (B) the area of increased wall thickness is shown by arrow.

Figure 2

Normal cross-section of the descending aortic wall in an 81-year old male without history of diabetes and hypertension, and no indication of atherosclerotic plaque (A). Descending aortic wall of a 67-year old male with history of hypertension (B) the area of increased wall thickness is shown by arrow.