MPI Summed Score Calculator
SDS, % myocardium, and severity from the summed stress and rest scores
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From the 17-segment summed stress score (SSS) and summed rest score (SRS), this computes the summed difference score (ischemia), the percent of myocardium ischemic and scarred, and the conventional severity category. Cutoffs are the widely-cited ranges; confirm against your lab's software and normal database (see MPI Interpretation & Grading).
17-segment MPI scorer — click each segment to cycle 0→4
Stress
Rest
%
SSS=Σstress, SRS=Σrest, SDS=SSS−SRS (ischemia). %myocardium = score÷68. Territories — LAD: 1,2,7,8,13,14,17 · LCx: 5,6,11,12,16 · RCA: 3,4,9,10,15. TID > ~1.2 and a post-stress LVEF drop are high-risk. Confirm against your lab software/normal database.
Evidence & sources
BBerman/ASNC quantitative perfusion scoring — 17-segment SSS/SRS/SDS, % myocardium, and severity ranges.
CThresholds are software/lab-specific — confirm against your normal database.