Prognostic impact of SYNTAX II score in patients with ST-elevation myocardial infarction undergoing Primary Percutaneous Coronary Intervention: analysis of a 4-year all-comers registry.

AIMS: This study aimed to investigate the prognostic impact of the SYNTAX II score (SS-II) of ST-segment elevation myocardial infarction (STEMI) patients undergoing a primary percutaneous coronary intervention (pPCI).

METHODS AND RESULTS: This retrospective cohort study included 1689 patients with STEMI who underwent pPCI between January 2008 and December 2016. The patients were categorized into three groups based on SS-II tertiles [SS-II low tertile < 24 (n=585), 25 ≤SS-II intermediate tertile ≤ 33 (n=567), and SS-II high tertile > 34 (n=537)]. In-hospital mortality was significantly lower in patients low and mid SS-II when compared with high SS-II (0.7% vs. 0.5% vs. 16.4%, p=0,001). During follow-up (median 2.35 years), high SS-II was positively correlated with MACE (12.3% for low SS-II vs. 18.3% for mid SS-II vs. 43.2% for high SS-II, p=0.001), all-cause mortality (1.5% vs. 3.9% vs. 14.2%, p=0.001) and heart failure (0.3% vs. 2.7% vs. 8.2%, p=0.001). The SS-II showed additive value on top of GRACE, anatomical SYNTAX score and residual SYNTAX score.

CONCLUSIONS: The SS-II in patients with STEMI undergoing pPCI adds important prognostic information regarding long-term adverse outcomes, being an independent and powerful predictor of MACE, heart failure and all-cause mortality during follow-up.