Contrast volume to glomerular filtration ratio and acute kidney injury among ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention

Introduction The ratio between contrast media volume to glomerular filtration rate (contrast/GFR) has been shown to correlate with the occurrence of contrast induced acute kidney injury (CI-AKI) in unselected patient populations who underwent percutaneous coronary intervention (PCI). We evaluated the possible utilization of this marker and optimal cutoff among ST elevation myocardial infarction (STEMI) patients undergoing primary PCI.

Materials and methods We retrospectively included 419 patients with STEMI treated with primary PCI. The occurrence of CI-AKI was defined by the KDIGO criteria as an increase in serum creatinine of ≥0.3 mg/dl within 48 hours following PCI. A receiver-operator characteristic curve was used to identify the optimal cutoff value of contrast/GFR ratio to predict CI-AKI. This value was then assessed using multivariable logistic regression.

Results and discussion The overall incidence of CI-AKI was 9%. The contrast/GFR ratio was significantly higher among patients with CI-AKI (2.7 ± 1.2vs. 1.9 ± 0.9; p <0.001). According to the ROC curve analysis, the optimal cutoff value of contrast/GFR ratio to predict AKI was measured as ≥ 2.13, with 70% sensitivity and 60% specificity (AUC 0.65, 95%CI 0.56-0.74, p = 0.002). In a multivariate logistic regression model contrast/GFR ratio ≥ 2.13 was independently associated with CI-AKI (OR 2.46, 95% CI 1.09-5.57; P=0.03).

Conclusion Among STEMI patients undergoing primary PCI, contrast/GFR ratio ≥ 2.13 was independently associated with CI-AKI.