SYNTAX Score Estimator Calculator

How it is calculated

This is a simple additive points scheme, not the clinical scoring done on a coronary angiogram. The score is built like this:

score = 2 × lesions + 5 (total occlusion) + 2 (bifurcation) + 2 (calcification) + 1 (thrombus)

Each feature adds its points only when it is switched on, and only once however many lesions have it. The lesion count must be a whole number from 1 to 20; anything else shows no result. The total is then placed in a tier: Low for 22 or below, Intermediate for 23 to 32, High for 33 or above. These cut-offs mirror the usual SYNTAX groupings, but the points per feature are fixed round numbers chosen for this estimator. The tool prints a note that it is not a clinical SYNTAX score and not medical advice, and it should never decide treatment.

Common mistakes

• Treating the number as a real SYNTAX score. A clinical score comes from a detailed, segment-by-segment reading of the angiogram by specialists; this tool only adds up a few flat points.
• Counting every narrowing as a lesion. Only significant lesions belong in the count, because each one is worth 2 points, so a loose count inflates the tier quickly.
• Ticking the same problem twice. A calcified lesion at a bifurcation is two separate feature boxes, but one lesion in the count.
• Forgetting that features are yes or no. Three occlusions still add 5 points once, not 15, so the score cannot show how many lesions have each feature.
• Entering a lesion count that is zero, fractional (such as 2.5) or above 20. The tool shows no result for these instead of a score.