Small proximal aortic diameter is associated with higher central pulse pressure and poor outcome in patients with congestive heart failure

Background: A small proximal aortic diameter (AoD) is thought to be associated with a higher characteristic impedance of the proximal aorta. However, there has been no evidence of a relationship between directly evaluated AoD and directly measured central aortic pressure or the outcome of patients with cardiovascular diseases. Methods and Results: (a) In 135 patients without heart failure (HF), who underwent coronary catheterization, we retrospectively examined the relationship between the AoD and the central aortic pressure or aortic elastance. The AoD adjusted with covariates was inversely correlated with the central pulse pressure (cPP; coefficient=−0.75; P= 0.04; model R 2 =0.575) and the effective arterial elastance index (coefficient=−0.12; P= 0.001; model R 2 =0.366). (b) In 197 patients who were hospitalized due to HF, we examined the relationship between the AoD (evaluated using echocardiography) and the outcome using a Cox proportional hazard model. Fifty-three patients died from various causes during the follow-up period (2.2±1.1 years). Multivariable analysis revealed that the AoD remained an independent risk factor for all-cause death (hazard ratio for 1 s.d. increase of the AoD: 0.68, 95% confidence interval: 0.50–0.92, P =0.013) and cardiovascular death (hazard ratio for 1 s.d. increase of the AoD: 0.63, 95% confidence interval: 0.43–0.93, P =0.019). Conclusions: A small AoD was associated with a higher cPP and aortic stiffening in the patients without HF, as well as with a poor outcome for HF patients. Although it is easy to evaluate the AoD, it may offer important information regarding the pulsatile load and may be useful for risk stratification of HF patients.