Version 2.77


The summed rest score (SRS), summed stress score (SSS) and summed difference score (SDS) are variables used to measure cardiac perfusion and ischemia on cardiac SPECT studies. The SRS and SSS are calculated during the rest and stress parts of the study, respectively, and the SDS is the difference between the two.
A five-point scoring system is used to assign a perfusion value to each of the 17 or 20 myocardial segments (depending on which segmentation model is used), each of which corresponds to a coronary artery segment territory, as follows: 0 = normal tracer uptake; 1 = equivocal tracer uptake; 2 = moderate reduction in uptake; 3 = severe reduction of uptake; and 4 = absence of detectable tracer uptake. The values for all of the segments are summed, giving a total possible SRS and SSS of 68 for the 17-segment model and 80 for the 20-segment model. The sum of the differences between the score at rest and score with stress for each segment is the SDS, which represents the amount of ischemia.
The SRS, SSS and SDS can be converted to a percent of the total myocardium involved with stress, ischemic, or fixed defects by dividing the summed scores by either 68 or 80 (the maximum possible score for the 17 and 20-segment model, respectively), and multiplying by 100.
PMID: 12771008 Source: Regenstrief LOINC, PMID: 12771008

Basic Part Properties

Part Display Name
Summed stress score
Part Type
Component (Describes the core component or analyte measured)
Created On
Construct for LOINC Short Name

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Language Variants Get Info

Tag Language Translation
it-IT Italian (Italy) Punteggio sommato delle immagini da sforzo
zh-CN Chinese (China) 总负荷评分
Synonyms: 总负荷(负荷灌注)评分(分值、得分、分数);总负荷评分;总和负荷分数;负荷灌注总评分(总分数、总得分、总分值、总分);summed stress score;SSS