Baseline and residual SYNTAX score in predicting outcomes after acute infarct angioplasty

The aim of this study was to explore the utility of baseline SYNTAX score (bSS) and residual SYNTAX score (rSS) in predicting 12-month outcomes after primary percutaneous coronary intervention (PPCI).

Five hundred and ninety all-comers with acute STEMI presenting for PPCI over a two-year period were identified. Of these, 173 were excluded because of unsuitability for SYNTAX score calculation for this study. Two experienced observers calculated the bSS and rSS. Mortality data were sourced from the government registry. Logistic regression was used to assess the predictive power of bSS and rSS for mortality. Sensitivity analysis and a Cox proportional hazards model were used to evaluate the best cut-off for increased mortality. Of the 417 patients analysed (mean age 59 years), 81% were male and 18% were known diabetics. At 12 months, the overall mortality rate was 5.5% (23/417). An rSS of >12 was associated with a 13.95% mortality rate. The hazard ratio for mortality was 3.88 (95% CI: 1.49-10.09, p=0.005) for rSS of >12 and 3.01 (95% CI: 1.18-7.64, p=0.02) for bSS >12. The odds ratio (OR) for mortality was 1.06 (95% CI: 1.02-1.11, p=0.009) for rSS and 1.05 (95% CI: 1.02-1.1, p=0.007) for bSS.

In STEMI patients undergoing PPCI, both bSS and rSS can predict mortality at 12 months. Every point on the rSS confers an additional 6% mortality risk. Calculation of the rSS after culprit lesion intervention may help guide management of non-culprit lesions.