Left main coronary artery diameter – A correlation between intravascular ultrasound and quantitative coronary angiography

Coronary angiography mostly underestimates coronary artery size. Indian data is scarce on correlating quantitative angiographic coronary diameter (DQCA) to intravascular ultrasound derived coronary diameter (DIVUS). We retrospectively analyzed 10-year data (2008–2017) of patients undergoing IVUS guided left main percutaneous coronary intervention (LM-PCI). LM, ostio-proximal LAD (op-LAD), and ostio-proximal LCX (op-LCX) were analyzed in 186, 177 and 44 patients, respectively. A linear correlation was noted between D IVUS and D QCA with derived equations for LM DIVUS = 1.68 + 0.69 × DQCA, op-LAD DIVUS = 1.91 + 0.53 × DQCA, op- LCX DIVUS = 1.93 + 0.49 × DQCA. We conclude that our equations could be used for an approximate estimation of true vessel size in the absence of IVUS assessment.