St‐segment elevation acute myocardial infarction complicated by cardiogenic shock: Early predictors of very long‐term mortality

Background. Cardiogenic shock (CS) is the leading cause of in‐hospital mortality in ST-segment elevation myocardial infarction (STEMI). Only limited data are available on the long‐term outcome of STEMI patients with CS undergoing contemporary treatment. We aimed to investigate long‐term mortality and its predictors in STEMI patients with CS and to develop a risk score for long‐term mortality prediction. Methods and Results. We retrospectively included 465 patients with STEMI complicated by CS and treated with primary angioplasty and intra‐aortic balloon pump between 2005 and 2018. Long‐term mortality, including both in‐hospital mortality and all‐cause mortality following discharge from the index hospitalization, was the primary endpoint. The longterm mortality (median follow‐up 4 (2.0–5.2) years) was 60%, including in‐hospital mortality (34%). At multivariate analysis, independent predictors of long‐term mortality were age (HR 1.41, each 10‐ year increase), admission left ventricular ejection fraction (HR 1.51, each 10%‐unit decrease) and creatinine (HR 1.28, each mg/dl increase), and acute kidney injury (HR 1.81). When these predictors were pooled together, the area under the curve (AUC) for long‐term mortality was 0.80 (95% CI 0.75–0.84). Using the four variables, we developed a risk score with a mean (cross‐validation analysis) AUC of 0.79. When the score was applied to in‐hospital mortality, its AUC was 0.79, and 0.76 when the score was applied to all‐cause mortality following discharge. Conclusions. In STEMI patients with CS, the risk of death is still substantial in the years following the index event. A simple clinical score at the time of the index event accurately predicts long‐term mortality risk.