Abstract

Abstract


Objective: To find predictors, incidence and hospital mortality of acute kidney injury in ST elevation myocardial infarction patients undergoing percutaneous coronary interventions.

Methods: The retrospective cross-sectional study was conducted at Tabba Heart Institute Karachi, and comprised data from June 2013 to December 2017 of ST elevation myocardial infarction patients undergoing percutaneous coronary interventions during index admission. Acute kidney injury was defined as serum creatinine ≥0.3 mg/dl 48hrs after percutaneous coronary intervention, and was further graded into stages I-III and the need for haemodialysis. Predicted acute kidney injury risks were calculated using Mehran and National Cardiovascular Data Registry risk scores. Stata 14 was used for statistical analysis.

Results: Of the 2766 cases evaluated, the incidence of acute kidney injury was found in 543(19.6%) case. Diabetes, pre-percutaneous coronary intervention heart failure, ejection fraction 2-3-fold increase; stage 3: >3-fold or serum creatinine >4mg/dl with an acute increase of >0.5mg/dl). AKI requiring dialysis (AKI-D) was an in-hospital outcome identified using a pre-defined NCDR data element for acute or worsening renal failure necessitating new renal dialysis. Glomerular filtration rate (GFR) was calculated using Cockroft Gault equation [(140-age) × weight ÷ S creatinine × 0.72 × (0.85 if female)].12 STEMI or equivalents were characterised by the presence of both criteria: a. symptoms suggestive of acute coronary ischemia, and, b. ECG evidence of STEMI. New or presumed new STsegment elevation or new left bundle branch block (LBBB) were measured with cut-off points: >0.2 mV in men or >0.15mV in women in leads V2-V3, and/or >0.1mV in other leads, or true posterior infarcts. LBBB refers to new or presumed new LBBB on the initial ECG. Detailed demographics, clinical presentation characteristics, inhospital non-invasive and invasive evaluation, medical management, and revascularisation by PCI and inhospital outcome were recorded. Approval was obtained from the institutional ethics review committee. On admission, patients were thoroughly explained with respect to storage of individual information and its use for research purposes while ensuring confidentiality of their identity and informed consent had been taken from all patients. Mehran score for contrast induced nephropathy (CIN) related AKI was utilised to calculate predicted risk of AKI 9. The score assigns points for 8 risk factors: hypotension, use of intra-aortic balloon pump (IABP), congestive heart failure (CHF), age >75 years, anaemia (haematocrit