Acute kidney injury and in-hospital mortality in patients with ST-elevation myocardial infarction of different age groups.

BACKGROUND: Acute kidney injury (AKI) is a well-known complication of ST-elevation acute myocardial infarction (STEMI) with an adverse impact on prognosis. Since AKI develops more frequently in elderly patients, we hypothesized that its higher incidence in older STEMI patients might explain their increased in-hospital mortality. We assessed the relationship between AKI and in-hospital mortality in patients with STEMI of different age groups. METHODS: We retrospectively evaluated 5136 STEMI patients treated with primary percutaneous coronary intervention (pPCI). We defined AKI as ≥0.5 mg/dl creatinine increase in the first 72 h. Patients were grouped according to age (<75 [n = 4040] or ≥ 75 [n = 1096] years). The primary endpoint was in-hospital mortality. RESULTS: The incidence of AKI was 7%. It was 4.6% in patients <75 years and 15.1% in those ≥75 years (P < 0.0001). The overall in-hospital mortality was 4%. It was 2.6% and 8.5% in patients younger and older than 75 years, respectively (P < 0.0001). It was higher in AKI than in non-AKI patients, both in the overall population (27% vs. 2%) and in the two age groups (25% vs. 2% and 29% vs. 5% in younger and older patients, respectively; P < 0.0001). The adjusted odds ratio of in-hospital mortality associated with AKI progressively decreased in parallel with increasing age decades (from 24.7 [95% CI 11.2-54.1] in patients <65 years to 3.9 [95% CI 1.6-9.7] in those >85 years). CONCLUSIONS: In STEMI patients treated with pPCI, AKI incidence and in-hospital mortality steadily increase with age. However, the prognostic impact of AKI is progressively reduced as age increases.

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 long-term 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.