Augmentation index relates to progression of aortic disease in adults with Marfan syndrome.

BACKGROUND: Noninvasive applanation tonometry (APT) is useful to assess aortic stiffness and pulse wave reflection. Moreover, APT can predict outcome in many conditions such as arterial hypertension. In this study, we test whether APT measurements relate to progression of aortic disease in Marfan syndrome (MFS).
METHODS: We performed APT in 50 consecutive, medically treated adults with MFS (19 men and 31 women aged 32 +/- 13 years), who had not undergone previous cardiovascular surgery. During 22 +/- 16 months of follow-up, 26 of these patients developed progression of aortic disease, which we defined as progression of aortic root diameters >or=5 mm/annum (18 individuals), aortic surgery >or=3 months after APT (seven individuals), or onset of acute aortic dissection any time after APT (one individual).
RESULTS: Univariate Cox regression analysis suggested an association of aortic disease progression with age (P = 0.001), total cholesterol levels (P = 0.04), aortic root diameter (P = 0.007), descending aorta diameter (P = 0.01), aortic root ratio (P = 0.02), and augmentation index (AIx@HR75; P < 0.006). Multivariate Cox regression analysis confirmed an independent impact on aortic disease progression exclusively for baseline aortic root diameters (hazard ratio = 1.347; 95% confidence interval (CI) 1.104-1.643; P = 0.003) and AIx@HR75 (hazard ratio = 1.246; 95% CI 1.029-1.508; P = 0.02). In addition, Kaplan-Meier survival curve analysis illustrated significantly lower rates of aortic root disease progression both with lower AIx@HR75 (P = 0.025) and with lower pulse wave velocity (PWV) values (P = 0.027).
CONCLUSIONS: We provide evidence that APT parameters relate to aortic disease progression in medically treated patients with MFS. We believe that APT has a potential to improve risk stratification in the clinical management of MFS patients.