Aortic Root Diameter and Arterial Stiffness: Conjoint Relations to the Incidence of Cardiovascular Disease in the Framingham Heart Study

Abstract

Higher central pulse pressure is associated with higher carotid-femoral pulse wave velocity (CFPWV) and an increased risk of cardiovascular disease (CVD). A smaller aortic root diameter (AoR) is associated with higher central pulse pressure. We hypothesized that the combination of a smaller AoR and higher CFPWV is associated with increased CVD risk (relative to a larger AoR and lower CFPWV). We tested this hypothesis in the community-based Framingham Study (N=1970, mean age 60 years, 57% women). We created sex-specific longitudinal echocardiographic AoR trajectories over 2 decades, categorizing participants into smaller versus larger AoR groups. We cross-classified participants based on their AoR trajectory and CFPWV (dichotomized at the sex-specific median). We used Cox regression to relate the cross-classified groups to CVD incidence on follow-up (median 17 years): lower CFPWV, larger AoR (referent group; 6.4/1000 person-years); lower CFPWV, smaller AoR (6.9/1000 person-years); higher CFPWV, larger AoR (23.1/1000 person-years); and higher CFPWV, smaller AoR (21.9/1000 person-years). In sex-pooled analyses, groups with higher CFPWV were associated with a multivariable-adjusted 1.8-fold risk of CVD ( P <0.01) regardless of AoR size. We observed effect modification by sex ( P for sex×AoR-CFPWV group interaction 0.04). In men, the group with smaller AoR and higher CFPWV was associated with a 2.5- to 2.8-fold risk of CVD ( P <0.001). In women, the group with larger AoR and higher CFPWV experienced a statistically nonsignificant 70% to 80% higher CVD risk. Our observations indicate that the prognostic significance of a smaller versus larger AoR varies in men versus women. Additional studies are warranted to confirm our findings.

Increased indexed proximal aortic diameter is a predictor of poor prognosis in maintenance hemodialysis patients

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Thoracic Aortic 3-Dimensional Geometry: Effects of Aging and Genetic Determinants

“…In addition to its conduit function, the aorta provides a cushioning function via its compliance, allowing for the near steady flow in the systemic microvasculature despite the intermittent left ventricular ejection. Aortic structural parameters (including geometry and wall stiffness) have been shown to be key determinants of pulsatile arterial hemodynamics 1,2 . A stiff aorta loses its cushioning function, resulting in excess arterial pulsatility and damage to the systemic microvasculature of target organs.…”

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