A comparison between two different definitions of contrast-induced acute kidney injury in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

Abstract

BackgroundContrast-induced acute kidney injury (CI-AKI) is associated with significantly increased mortality after primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI). The prognostic value of CI-AKI depends on the definitions used to define it. We compare the predictive accuracy of long-term mortality of two definitions of CI-AKI on consecutive patients undergoing pPCI for STEMI. MethodsIncidence, risk factors and long-term prognosis of CI-AKI were assessed according to two different definitions: the first as an increase in serum creatinine ≥25% or ≥0.5mg/dl from baseline within 72h after pPCI (contrast-induced nephropathy (CIN) criteria), the second one according to Acute Kidney Injury Network (AKIN) classification system. ResultsA total of 402 patients were enrolled. The median follow-up period was 12±4months. Long-term mortality rate was 9.5%. Independent predictors of long-term mortality were: older age, basal renal impairment, left ventricular ejection fraction <40%, in-hospital major bleedings and CI-AKI. A significant correlation was found between mortality and CI-AKI as assessed by both CIN (HR 4.84, 95% CI: 2.56–9.16, p=0.000) and AKIN (HR 9.70, 95% CI: 5.12–18.37, p=0.000) definitions. The area under the receiver operating curve was significantly larger for predicting mortality with AKIN classification than with CIN criteria (0.7984 versus 0.7759; p=0.0331). ConclusionsIn patients with STEMI treated by pPCI, CI-AKI is a frequent complication irrespective of the criteria used for its definition. AKIN, however, seems to provide a better accuracy in predicting long-term mortality than CIN criteria.