Abstract 11388: The Ratio of Contrast Medium Dose and Estimated Glomerular Filtration Predicts Contrast-Induced Acute Kidney Injury Among Patients for Elective Percutaneous Coronary Intervention
Background: The occurrence of contrast-induced acute kidney injury (CI-AKI) among patients undergoing percutaneous coronary intervention (PCI), is proven to be related to increased mortality and morbidity. Major risk factors associated with CI-AKI are often non-modifiable. Recent studies show that by adjusting the contrast media (CM) dose, which is one of the few modifiable risk factors, based on renal function reduces the incidence of CI-AKI.
Objective: To determine if CM dose, in grams of Iodine, to the estimated glomerular filtration rate ratio (g-I/eGFR) of greater than 1.42 predicts CI-AKI among patients who underwent elective PCI.
Methods and Results: This is a retrospective study of all patients who underwent elective PCI from January 1, 2008 to September 30, 2012 in our institution. Out of 1376 patients who had elective PCI, only 675 patients met the inclusion criteria and were eligible for analysis. The prevalence of CI-AKI is 8.4%. A g-I/eGFR of >1.42 has a sensitivity of 79% and specificity of 80% in predicting CI-AKI, with a positive and negative predictive values of 27% and 98%, respectively. Among patients with g-I/eGFR of >1.42 who developed CI-AKI, the relative risk is 11.41 (95% CI, 6.18 [[Unable to Display Character: –]] 21.04), p <0.0001, furthermore those with diabetes, hypertension and left ventricular ejection fraction (LVEF) of <45% have the relative risks of 9.98 (95% CI, 4.50 [[Unable to Display Character: –]] 22.16), p <0.0001, 10.99 (95% CI, 5.80 [[Unable to Display Character: –]] 20.81), p <0.0001 and 4.28 (95% CI, 1.50 [[Unable to Display Character: –]] 12.21), p 0.006 respectively. LVEF is predictive of CI-AKI, those with LVEF of >45% has the best g-I/eGFR cut-off value of 1.42 based on ROC-AUC (0.841), and although with lesser sensitivity, those with LVEF <45% with decreased eGFR has the best g-I/eGFR cut-off value of 1.56 at ROC-AUC (0.661). By deriving the contrast media dose from the g-I/GFR ratio of 1.42 for the general population or those with LVEF >45%, we can be guided to administer the safe limit of contrast volume during PCI:
Contrast volume (mL) = (1.42 x eGFR) / 0.37g/mL where, 0.37g/mL [[Unable to Display Character: –]] Iodine concentration of contrast media
Conclusion: The ratio of CM dose to creatinine clearance is predictive of CI-AKI. A g-I/eGFR ratio of <1.42 is a useful guide in limiting the contrast dose based on the baseline eGFR values before an elective PCI.
- © 2013 by American Heart Association, Inc.