Analyzing the prevalence of proximal aorta dilatation and its risk factors using Z-score

Abstract

Objective Using Z-score to assess the prevalence of proximal aorta dilatation in middle-aged and aged individuals during routine transthoracic echocardiogram examinations and to identify its risk factors. Methods A total of 823 middle-aged or elderly patients on routine transthoracic echocardiogram examinations were consecutively enrolled.The internal diameters of the sinus of Valsalva(SoV)and the ascending aorta(AA)were measured.Z-scores were calculated according to the proposed equation for SoV and AA.A dilated aortic root was defined as a Z-score ≥1.96 or the diameter of SoV or AA ≥40 mm.The prevalence of proximal aorta dilatation and associated factors were analyzed. Results The prevalences of proximal aorta dilatation, SoV dilatation, and AA dilatation were 26.1%(25/823), 6.0%(49/823), and 23.7%(195/823), respectively.In the aortic root dilatation group, age and the proportion of obesity were higher (both P<0.05), and there were more female subjects (30.5% or 117/384 vs.22.3% or 98/439, P<0.01). The incidences of left atrial dilation, left ventricular dilation, left ventricular hypertrophy, and aortic regurgitation in the aortic root dilatation group were higher than those in the non-aortic root dilatation group(P<0.05). Logistic regression analysis demonstrated that sex (OR=1.827, 95%CI: 1.248-2.673, P=0.002), hypertension (OR=1.441, 95%CI: 1.000-2.075, P=0.050)and left ventricular hypertrophy (OR=1.827, 95%CI: 1.248-2.673, P=0.002)were independently correlated with aortic root dilatation. Conclusions The prevalence of proximal aorta dilatation is high in middle-aged and aged individuals.Proximal aorta dilatation is related to sex, age, and body size, and it is often accompanied by structural abnormalities of the heart. Key words: Aorta; Dilatation, pathologic; Echocardiography