Risk Factors Of Contrast-induced Acute Kidney Injury In Patients Who Underwent An Emergency Percutaneous Coronary Intervention

Part One:Risk Factors of Contrast-induced Acute Kidney Injury in Patients who underwent an Emergency Percutaneous Coronary InterventionObjectives:Previous studies of contrast-induced acute kidney injury(CI-AKI)were mostly based on elective percutaneous coronary intervention(PCI)cases,and risk factors of CI-AKI after emergency PCI are unclear.The aim of this study was to explore the risk factors of CI-AKI in a Chinese population who underwent an emergency PCI.Methods:A total of 1061 consecutive patients who underwent an emergency PCI during January 2013 and June 2015 were enrolled and divided into CI-AKI and non-CI-AKI group.Univariate and multivariate analysis were used to identify the risk factors of CI-AKI in emergency PCI patients.CI-AKI was defined as an increase in serum creatinine(SCr)≥25%or≥0.5 mg/dL(44.2μmol/L)above baseline within 3 days after exposure to contrast medium.Results:The incidence of CI-AKI in patients who underwent an emergency PCI was 22.7%(241/1061).Logistic multivariate analysis showed body surface area(BSA)[OR 0.213,95%CI:0.075-0.607,P=0.004],history of myocardial infarction(MI)[OR 1.642,95%CI:1.079-2.499,P=0.021],preprocedural left ventricular ejection fraction(LVEF)[OR 0.969,95%CI:0.944-0.994,P=0.015],preprocedural hemoglobin(Hb)[OR 0.988,95%CI:0.976-1.000,P=0.045],preprocedural estimated glomerular filtration rate(eGFR)[OR 1.027,95%CI:1.018-1.037,P<0.001],left anterior descending(LAD)stented[OR 1.464,95%CI:1.000-2.145,P=0.050],and diuretics use[OR 1.850,95%CI:1.233-2.777,P=0.003]were independent predictors of CI-AKI in patients who underwent an emergency PCI.Conclusion:History of MI,low BSA,preprocedural LVEF and Hb levels,a high preprocedural eGFR,LAD stented and diuretics use are associated with increased risk of CI-AKI in patients who underwent an emergency PCI.Part Two:Relationship between the Level of Big Endothelin-1 and Contrast-induced Acute Kidney Injury in Patients who underwent an Emergency Percutaneous Coronary InterventionObjectives:With wide application of percutaneous coronary intervention(PCI)technology in patients with coronary artery disease,contrast-induced acute kidney injury(CI-AKI)has become one of serious complications.Dysfunction of vascular endothelium was proved to be a key mechanism in development of CI-AKI,and the aim of this study was to explore the relationship between the level of big endothelin-1 and CI-AKI in patients who underwent an emergency PCI.Methods:A total of 1061 consecutive patients who underwent an emergency PCI in Fuwai Hospital during January 2013 and June 2015 were enrolled and divided into low,moderate and high level groups according to the endothelin-1 value distribution.Baseline and procedural characteristics of three groups were analyzed,and the incidences of CI-AKI and composite endpoint events(including nonfatal myocardial infarction,revascularization,stroke,all-cause death)at 6 and 12 month follow-up of three groups were compared.The risk factors of CI-AKI were identified by logistic analysis.CI-AKI was defined as an increase in serum creatinine(SCr)≥25%or≥0.5 mg/dL(44.2μmol/L)above baseline within 3 days after exposure to contrast medium.Results:The incidence of CI-AKI in patients who underwent an emergency PCI was 22.7%(241/1061).The incidence of CI-AKI and composite endpoint events rates at 6 and 12 month follow-up in three groups were all with significant differences(P=0.001,<0.001 and =0.026,respectively).The CI-AKI rate in high level group was significantly higher than those in low level(P<0.001)and moderate level group(P=0.008).After adjustment for covariates,big endothelin-1 was still an independent risk factor of CI-AKI either as a continuous variate or a categorical variate.Conclusions:The high level of endothelin-1 is associated with an increased risk for CI-AKI in patients who underwent an emergency PCI.Vascular endothelial dysfunction might be a key mechanism in the development of CI-AKI.Part Three:A Novel Risk Model of Contrast-induced Acute Kidney Injury in Patients who underwent an Emergency Percutaneous Coronary InterventionObjectives:Prior risk scoring systems of contrast-induced acute kidney injury(CI-AKI)were mostly based on elective percutaneous coronary intervention(PCI)patients,which might be inappropriate for emergency cases.The risk factor profile and their cumulative effect in patients who underwent an emergency PCI have not been well studied in a large cohort.The aim of our study was to develop a novel risk model for predicting CI-AKI in patients who underwent an emergency PCI.Methods:A total of 1061 consecutive patients who underwent an emergency PCI in Fuwai Hospital during January 2013 and June 2015 were enrolled in our study.The included patients were divided into two groups chronologically:the derivation group(n=761)to establish the risk scoring system,and the validation group(n=300)to test it.CI-AKI was defined by 1 of 3 definitions:(1)serum creatinine(SCr)increase≥25%above baseline in 72 hours after procedure;(2)SCr increase ≥0.5 mg/dL(44.2μmol/L)in 72 hours after PCI;(3)SCr increase ≥0.5 mg/dL(44.2 μmol/L)in 7 days.The most appropriate one was to be explored and used during the establishment of the novel risk score model.Results:The rates of CI-AKI were 23.5%(SCr increase ≥25%in 72 hours),4.3%(SCr increase ≥0.5 mg/dL or 44.2 μmol/L in 72 hours),and 7.0%(SCr increase ≥0.5 mg/dL or 44.2 μmol/L in 7 days).Due to the high sensitivity of definition one and the high rate of missed diagnosis for late CI-AKI under definition two,the novel risk score model was established based on the definition three.The novel risk scoring system of CI-AKI was constituted by 6 variates:body surface area(BSA)<1.6 m2(3 points),history of transient ischemic attack(TIA)/stroke(3 points),white blood cell(WBC)count>15.00×109/L(2 points),preprocedural estimated glomerular filtration rate(eGFR)<60 ml/min·1.73m2(3 points)or baseline SCr>133μmol/L(4 points),intro-aortic balloon pump(IABP)(3 points)and use of diuretics(7 points),showing great discriminating power in derivation(c-statistic=0.847,95%CI:0.792-0.902)and validation dataset(c-statistic=0.845,95%CI:0.788-0.902).The emergency PCI patients could be stratificated into four CI-AKI risk level:low risk(≤5 points),moderate risk(6-10 points),high risk(11-15 points)and very high risk(≥16 points).The rates of CI-AKI increased exponentially with increasing risk classification(P<0.001).Conclusions:The newly developed risk scoring model is easily applicable and allows accurate prediction of CI-AKI in patients who underwent an emergency PCI.