Left Main and Right Coronary Artery Diameter and Left Ventricular Mass associated with coronary artery collaterals in Ischaemic heart disease: A Cardiovascular Imaging Study

Purpose: Coronary artery collateral circulation is a novel factor in assessing ischemic heart disease (IHD). However, it requires specialised assessment and cannot be evaluated retrospectively. Theoretically, a ‘normalised’ coronary artery diameter would indicate the coronary artery collateral status. This study explores associations between coronary artery collaterals with left main and right coronary artery diameter, left ventricular mass, and a ratio of coronary artery diameters to left ventricular mass (CAA-LVM). We hypothesise an association between the status of coronary artery collaterals and the CAA-LVM ratio. Methods: A prospective study of 378 patients with suspected IHD to explore the association between the coronary artery collaterals and CAA-LVM ratio from angiograms and echocardiograms. Univariate and subsequent multivariable binary logistic regression were conducted to assess the associations. Results: The study's findings showed coronary artery collaterals was significantly associated with left main coronary artery (adjusted odds ratio, AOR: 16.321, 95% CI: 4.316, 61.713, p -value: <0.001), right coronary artery (AOR:6.056, 95% CI: 1.509, 24.305, p -value: 0.01), and CAA-LVM ratio (AOR: 3.256, 95% CI: 1.305, 8.125, p- value : 0.01). Conclusion: This study demonstrated that a larger CAA–LVM ratio was observed in patients with increased coronary collateral formation. This technique may serve as an adjunct to the currently available techniques in identifying collaterals and may also help assess collateral circulation amid limited resources.