A new classification system for LM bifurcation/ trifurcation lesions has been proposed. 1. Following nomenclature has been suggested: A/a for LM coronary artery B/b for LAD artery C/c for left circumflex coronary artery D/d for ramus intermedius artery (intermediate branch) Whether a capital or small letter would be used, depends upon the diameter of the vessel as explained below. 2. Each artery is given one of the above-mentioned letters if the stenosis is considered to be significant (i.e., >70% in lumen reduction visually, or based on FFR or other resting indices, cCT-cFFR, IVUS, OCT). 3. If the stenosis is not considered significant, no letter would be assigned. 4. A capital letter is used if the vessel diameter is ≥3.5 mm, while a small letter is used if the diameter is smaller than 3.5. 5. The image below has significant stenosis in all three vessels i.e LM, LAD and LCx...