Acute kidney injury based on the KDIGO criteria among ST elevation myocardial infarction patients treated by primary percutaneous intervention

Background: Acute kidney injury (AKI) following acute ST elevation myocardial infarction (STEMI) is associated with adverse outcomes. The recently proposed KDIGO criteria suggested modifications to the consensus classification system for AKI, namely lowering the threshold of increase in absolute serum creatinine and extending the time frame for AKI detection to 7 days. We evaluated the incidence, risk factors, and long-term mortality associated with AKI as classified by the KDIGO definition in a large single center cohort of consecutive STEMI patients. Methods: We retrospectively studied 2122 consecutive STEMI patients undergoing primary percutaneous coronary intervention (PCI). Recruited patients were admitted between January 2008 and May 2016 to the cardiac intensive care unit with the diagnosis of acute STEMI. We compared the utilization of the KDIGO and consensus criteria for the diagnosis of AKI and its relation to long term mortality. Results: The KDIGO criteria allowed the identification of more patients as having AKI (10.6 vs. 5.6%, p < 0.001) compared to the consensus criteria. Even mild elevation of serum creatinine (≥ 0.3 mg/dL) was associated with a marked increase in all-cause mortality (HR 4.7, 95% CI 3.1–6.43, p < 0.001). Patients with AKI whose renal function resolved prior to hospital discharge still had significantly higher mortality compared to patients with no AKI (23 vs. 8%, HR 3.1, 95% CI 2.09–4.90, p < 0.001). Conclusion: KDIGO criteria is more sensitive than the consensus criteria in defining AKI in STEMI patients and identifying populations at risk for long term adverse outcomes.