BackgroundST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (pPCI) are at increased risk for contrast-induced nephropathy (CIN) than elective PCI procedures. Routine calculation of Mehran’s score is limited by its complexity and difficulty to memorize. This study evaluated CHA2DS2-VASc score predictive utility for CIN in STEMI patients before pPCI.ResultsConsecutive 500 acute STEMI patients presenting to two Egyptian pPCI centers were recruited. Exclusion criteria included cardiogenic shock or known severe renal impairment (baseline serum creatinine ≥ 3 mg/dL) or current or previous indication of hemodialysis. CHA2DS2VASCscore,Mehran’s score, baseline estimated glomerular filtration rate (eGFR), contrast media volume (CMV) and CMV/eGFR ratio were collected for all patients. Post-pPCI CIN (defined as 0.5 mg/dL absolute increase or 25% relative increase of serum creatinine from baseline) and predictive accuracy of CHA2DS2VASCand Mehran’s scores were evaluated. CIN occurred in 35 (7%) of the study group. Values of CHA2DS2VASCscore,Mehran’s score, baseline eGFR, CMV and CMV/eGFR ratio were significantly higher in those who developed CIN compared to those who did not. CHA2DS2VASCscore,Mehran’s score and CMV/eGFR were found to be independent predictors for CIN (P< 0.001 for all). ROC curve analysis revealed that CHA2DS2VASC≥ 4 had a superb predictive ability, comparable to Mehran’s score, for post-pPCI CIN.ConclusionsBeing practical, easily memorizable and applicable before proceeding to pPCI, routine CHA2DS2VASCscore calculation in STEMI patients can effectively predict CIN risk and guide preventive and/or therapeutic interventions.