Case 1


Case 1 should be described in the SYNTAX Score as one lesion in segment 5 – lesion characteristic: aorto ostial Left Main Coronary Artery (LMCA).
(Definition: a lesion is classified as aorto ostial when it is located immediately at the origin of the vessel from the aorta)

Case 2



Case 2 should be described in the SYNTAX score as one lesion in segment 5 – lesion characteristic: long lesion (20mm or more).

Case 3



Case 3 should be described in the SYNTAX score as one lesion in segment 5 – lesion characteristic: Bifurcation class 1,0,0.

Case 4

Case 4a (concentric):


Case 4b (eccentric):


Case 4 should be described in the SYNTAX score as one lesion involving segment 5 and segment 6 – lesion characteristic: Bifurcation class 1,1,0.

Case 5

Case 5a:


Case 5b:


Case 5a should be described in the SYNTAX score as one lesion involving segment 5 and segment 11 – lesion characteristic: Bifurcation class 1,0,1.
Note that the main distal vessel should be the branch with the largest diameter. In 5A, the LAD (segment 6) is the main distal vessel.

Case 5b should be described in the SYNTAX score as one lesion involving segment 5 and segment 11 – lesion characteristic: Bifurcation class 1,1,0
Note that the main distal vessel should be the branch with the largest diameter. In 5B, the LCX (segment 11) is the main distal vessel.

Case 6



Case 6 should be described in the SYNTAX score as one lesion involving segments 5, 6 and 11 – lesion characteristic: ‘true bifurcation’ class 1,1,1.

Case 7

Case 7a:


* 3 or more vessel reference diameters

Case 7b:


* less than 3 vessel reference diameters

NB: Serial stenoses which are less than 3 reference vessel diameters apart, should be scored as one lesion. Stenoses at a greater distance from each other (more than 3 reference vessel diameters), are considered as separate lesions.

Case 7a should be described in the SYNTAX score as two lesions:
1) one lesion involving segments: 5, 6 and 11 (lesion characteristic: ‘true bifurcation’ class 1,1,1) and
2) one lesion involving segment 6.

Case 7b should be described in the SYNTAX score as one lesion: 1) one lesion involving segments: 5, 6 and 11 (lesion characteristic: ‘true bifurcation’ class 1,1,1)

Case 8





Case 8 should be described in the SYNTAX score as one lesion involving segment 6 and segment 11 – lesion characteristic: bifurcation class 0,1,1.
Note that the main distal vessel should be the branch with the largest diameter. In these examples, the LAD (segment 6) is the main distal vessel.