The primary results of our study reveal that the burden of angiographic disease detected by CTA provides both independent and incremental value in predicting all-cause mortality in symptomatic patients independent of age, gender, conventional risk factors, and CAC.

Objective-To establish the normal criterion of ascending aortic diameter (AAOD) measured by 64 Multi-Detector Computed Tomography (MDCT) and Electron Beam Computed Tomography (EBT) based on gender and age.Methods-1442 consecutive subjects who were referred for evaluation of possible coronary artery disease underwent coronary CT angiography (CTA) and coronary artery calcium scanning (CACS) (55+11 years, 65% male) without known coronary heart disease, hypertension, chronic pulmonary and renal disease, diabetes and severe aortic calcification. The ascending aortic diameter, descending aortic diameter (DAOD), pulmonary artery (PAD) and chest anterioposterior diameter (CAPD), posterior border of sternal bone to anterior border of spine, were measured at the slice level of mid right pulmonary artery by using end systolic trigger image. The volume of four chambers, ejection fraction of left ventricle, and cardiac output were measured in 56% of the patients. Patients demographic information, age, gender, weight, height and body surface area (BSA), were recorded. The mean value and age specific and gender adjusted upper normal limits (mean + 2 standard deviations) were calculated. The linear correlation analysis was done between AAOD and all parameters. The reproducibility, wall thickness and difference between end systole and diastole were calculated.Result-AAOD has significant linear association with age, gender, descending aortic diameter and pulmonary artery diameter (P<0.05). There is no significant correlation between AAOD and body surface area, four chamber volume, LVEF, CO and CAPD. The mean Intra-luminal AAOD was 31.1 ± 3.9mm and 33.6 ± 4.1 mm in females and males respectively. The upper normal limits (mean + 2 standard deviations) of Intra-luminal AAOD, mean+ standard deviation, was 35.6, 38.3 and 40 mm for females and 37.8, 40.5 and 42.6 mm for males in age group 20 to 40, 41 to 60, above 60 year respectively. Intra-luminal should parallel echocardiography and invasive angiography. Traditional cross sectional imaging (with computed tomography and magnetic resonance imaging) includes the vessel wall. The mean total AAOD was 33.5mm and 36.0 mm in females and males respectively. The upper normal limits (mean + 2 standard deviations) of Intra-luminal AAOD, mean+ standard Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Conclusion-The ascending aortic diameter increases with age and male gender. Gender specific and age adjusted normals for aortic diameters are necessary to differentiate pathologic atherosclerotic changes in the ascending aorta. Use of intra-luminal or...