Ostial side branch stenosis in non-stenotic coronary segments: a characteristic finding in diabetes mellitus.

2.BackgroundOstial stenosis, a narrowing at the origin of coronary side branches, is commonly observed in branches diverging from stenotic coronary segments. However, it may also occur in branches diverging from non-stenotic segments, and the factors contributing to this phenomenon remain unclear. ObjectivesThis study aimed to assess the incidence of ostial stenosis in coronary side branches diverging from non-stenotic segments and to identify associated risk factors. MethodsWe conducted a retrospective analysis of first-time, elective coronary angiograms (CAGs) from 884 patients. Side branches with a diameter larger than 2mm were included. Ostial stenosis was defined by two criteria: 1) the side branch diverged from a coronary segment with less than 25% diameter stenosis, and 2) the side branch exhibited ostial narrowing with more than 50% diameter stenosis. Clinical factors, including diabetes mellitus and lipid profiles, were assessed. Multivariate logistic regression was used to identify independent predictors of ostial stenosis. ResultsOf the 4,739 side branches analyzed, 508 (10.7%) exhibited ostial stenosis. Ostial stenosis was present in 285 (32.2%) patients. Patients with ostial stenosis had a significantly higher prevalence of diabetes mellitus (60.0% vs. 33.0%, p<0.00001) and lower high-density lipoprotein (HDL) cholesterol levels (48.5 {+/-} 14.6 mg/dL vs. 52.0 {+/-} 14.9 mg/dL, p<0.01) compared to those without stenosis. No significant differences were found in other clinical factors. Multivariate analysis identified diabetes mellitus as an independent predictor of ostial stenosis (odds ratio: 0.29, 95% CI: 0.20-0.43, p<0.0001). ConclusionsOstial stenosis in side branches diverging from non-stenotic coronary segments is significantly associated with diabetes mellitus. In diabetic patients, factors such as negative arterial remodeling, insulin resistance, and endothelial dysfunction likely play key roles in the development of this condition. These findings suggest that ostial stenosis could be an additional marker of advanced coronary artery disease in diabetes.