Criteria of complex bifurcation lesions
| Criteria | Lesion characteristics |
| Major 1 | Distal LM bifurcation: SB-DS ≥70% and SB lesion length ≥10 mm |
| Major 2 | Non-LM bifurcation: SB-DS ≥90% and SB lesion length ≥10 mm |
| Minor 1 | Moderate to severe calcification |
| Minor 2 | Multiple lesions |
| Minor 3 | Bifurcation angle <45° or >70° |
| Minor 4 | Main vessel RVD <2.5 mm |
| Minor 5 | Thrombus-containing lesions |
| Minor 6 | MV lesion length ≥25 mm |
| Major 1+any 2 minor 1–6=complex bifurcation lesion | |
| Major 2+any 2 minor 1–6=complex bifurcation lesion | |
DS, diameter stenosis; LM, left main; MV, main vessel; RVD, reference vessel diameter; SB, side branch.