Usefulness of the SYNTAX Score II to Predict In-Hospital and Long-Term Mortality in ST-Segment Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention

OBJECTIVES: The prognostic significance of SYNTAX Score II (SS-II) is well-known in patients with chronic coronary syndromes. However, its predictive ability for mortality in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (p-PCI) remains unclear. Therefore, we aimed to investigate the prognostic accuracy of SS-II in STEMI patients who underwent p-PCI. METHODS: A total of 743 STEMI patients treated with p-PCI were retrospectively analyzed. Study population was divided into three groups according to SS-II and defined as SS-IILOW ≤22.5 (n=245), 22.5 <SS-II MID ≤31 (n=243) and SS-II HIGH >31 (n=255). In-hospital and long-term mortality at long-term follow-up were defined as clinical endpoints of the study. RESULTS: The incidence of in-hospital (15% vs. 0.4% vs. 0.8%, p<0.001) and all-cause mortality (32.2% vs. 6.6% vs. 2.9%, p<0.001) were significantly higher in SS-IIHIGH group compared with the other two groups. In addition, Kaplan–Meier analysis showed statistically significantly increased incidence of death in SS-II > 31 group (P [log-rank] <0.001). SS-II >31 was defined as an independent predictor of all-cause mortality (hazard ratio 5.22 95% confidence interval 2.11–12.87 p<0.001). Area under the curve values derived from ROC analysis to evaluate the predictive accuracy of SS-II, anatomical and clinical SS, modified ACEF score, and Global Registry of Acute Coronary Events risk scores for all-cause mortality were 0.82, 0.71, 0.81, 0.82, and 0.82, respectively (p<0.001). CONCLUSION: SS-II has an increased predictive ability for in-hospital and long-term mortality in STEMI patients undergoing p-PCI.