The co-existence of expansive arterial remodelling in both coronary arteries (CAs) and the abdominal aorta has already been reported, although the clinical indicators and quantitative analysis have not been well studied. We therefore aimed to clarify the clinical and anatomical characteristics of patients with abdominal aortic aneurysms (AAAs). 123 AAA patients who underwent coronary angiography were compared to 123 control patients selected by propensity score matching. CA diameters of all 3 vessels were measured by quantitative coronary angiographic analysis. Coronary artery ectasia (CAE) was defined as local or generalized aneurysmal change of the CAs. Excessive expansive CA remodelling was defined as the maximal diameter of the right or left circumflex artery in the upper 75th percentile (>4.8 mm). Multivariable logistic regression analyses were used to determine predictors of CAE and excessive expansive CA remodelling. The prevalences of CAE and excessive expansive CA remodelling were significantly higher in the AAA group than in the non-AAA group (28% vs. 8% and 31% vs. 19%; both p<0.05). On multivariable analysis, the presence of AAA (odds ratio (OR), 4.56; 95% confidence intervals (95%CI) 2.18-10.4) and body mass index (BMI) (OR, 1.11; 95%CI 1.03-1.21) were independently associated with CAE, and higher high-sensitivity C-reactive protein (OR, 2.19; 95%CI 1.08-4.52) and BMI (OR, 1.11; 95%CI 1.02-1.21) were independently associated with excessive expansive CA remodelling. In conclusions, this study showed a higher prevalence of ectatic CA disease in AAA patients and suggests that higher inflammation and obesity are associated with expansive arterial remodelling in coronary arteries.