We aimed to design a rapid and reliable method to identify coronary lesions at high risk for the no-reflow phenomenon before elective coronary stent implantation using integrated backscatter intravascular ultrasound (IB-IVUS). The no-reflow phenomenon occurring during elective percutaneous coronary intervention (PCI) worsens patient prognosis, regardless of whether the phenomenon is transient or persistent. We retrospectively studied 353 coronary lesions to identify factors potentially promoting the no-reflow phenomenon, including lesion location and severity. We also performed component analysis by two- and three-dimensional IB-IVUS before elective stent implantation. The cutoff values of the true lipid volume and estimated lipid volume (lipid area at the minimal lumen diameter site × total stent length) for the no-reflow phenomenon were determined by receiver operating curve analysis. Type C lesions, regardless of location and a thrombolysis in myocardial flow grade of 0, were risk factors for the no-reflow phenomenon during PCI. The estimated lipid volume was significantly correlated with the true lipid volume (R 2 = 0.778, p < 0.0001). The cutoff value of the estimated lipid volume for the no-reflow phenomenon was 132.6 mm3 (area under the curve = 0.719), and the predictive value was equivalent to that of the true lipid volume. Lesions with an estimated lipid volume of ≥132.6 mm3 had a significantly higher risk of the no-reflow phenomenon during elective stent implantation (odds ratio, 4.35; 95 % confidence interval, 1.67-12.7; p = 0.0024). The simple and rapid measurement of the estimated lipid volume immediately before stenting during PCI constitutes a reliable predictor of lesions at high risk for the no-reflow phenomenon.
Keywords: Elective percutaneous coronary intervention; Integrated backscatter intravascular ultrasound; Lipid-rich plaque; No-reflow phenomenon.