Coronary artery bifurcation lesion is a common lesion subset in PCI accounting for 15-20% of the total number of interventions. Treatment of coronary artery bifurcation lesions represents a challenging area in interventional cardiology. When compared with non-bifurcation interventions, bifurcation interventions have a lower rate of procedural success, higher procedural costs, longer hospitalization and a higher clinical and angiographic restenosis. Factors contributing to this adverse outcome include limitations of angiography in assessment of side-branch (SB) disease severity and the lack of established angiographic predictors of SB patency and lumen compromise. Better understanding of the underlying plaque morphology and plaque composition may facilitate more effective treatment of bifurcation lesions.