Ischemic Heart Diseases (IHD) among Asian Indian migrants in the western world are documented with high prevalence. We aimed to assess population specific variation in artery dimensions among normal and Single Vessel Disease (SVD) patients among four states of Southern India: Telangana, Karnataka, Kerala and Tamil Nadu using Quantitative Coronary Angiography (QCA) in the disease presentations. QCA of four thousand patients of Indian origin were studied prospectively after procuring the ethical clearance. Informed consents were obtained. Post Percutaneous Coronary Angioplasty (PCI) as well as Post Coronary Bypass Operations (CABG) and patient being diabetic for ≥5 years were excluded. Principal Component Analysis (PCA) was performed with samples to identify region-specific clustering.

Purpose of research: To validate the Multiple Linear Regression Equation (MLR) of predicted dimensions of left anterior descending coronary artery (LAD-o, p) and left circumflex artery (LCx-o, p) by remodelling the equation based on the percentage of stenosis present in the artery segments. This helped us to go forward with an objective to explore the possibility of explaining the relationship with a MLR formula, to estimate the reference diameter of a stenosed coronary artery when the other two arteries are normal. Materials and methods: Patients who undergo Percutaneous Coronary Angioplasty (PCI) procedure were included from single study centre of South India after obtaining the ethical clearance through proper channels. Total n=104 cases who have undergone PCI in LAD-p were studied prospectively. Informed consent was obtained. Exclusion criteria’s were post CABG and post PCI patients. The parameters assessed and categorized were coronary artery measurements of non-diseased segments from Single Vessel Diseased Coronaries (SVD) after excluding the diseased segments. Results and conclusions: The initial participant predicted equation for LAD-p was remodelled after validation by considering the difference between stent size estimated (calculated) and stent reduction category. Participant predicted equation: LAD-p=1.092+0.302*LMCA+0.379 * LCx-p. F (2,101) = 1340, p<0.0001; with an R2 of 0.9637. Age and gender had no significant change while taking in to consideration for remodelling (p =0.17). PCI was found to be safe and effective in our routine clinical setting during the validation of the estimated MLR formula and was valuable in detecting the artery diameter in stenosed SVD of LAD-p. Keywords: Percutaneous coronary angioplasty; Multiple linear regression equation; Left anterior descending artery; Single vessel diseased coronaries; Stenting strategies.