High Risk Of Contrast-induced Acute Kidney Injury Research Articles

Association of plasma free triiodothyronine levels with contrast-induced acute kidney injury and short-term survival in patients with acute myocardial infarction.

ObjectivePost-treatment contrast-induced acute kidney injury (CI-AKI) is associated with poor outcomes in patients with acute myocardial infarction (AMI). A lower free triiodothyronine (FT3) level predicts a poor prognosis of AMI patients. This study evaluated the effect of plasma FT3 level in predicting CI-AKI and short-term survival among AMI patients.MethodsCoronary arteriography or percutaneous coronary intervention was performed in patients with AMI. A 1:3 propensity score (PS) was used to match patients in the CI-AKI group and the non-CI-AKI group.ResultsOf 1480 patients enrolled in the study, 224 (15.1%) patients developed CI-AKI. The FT3 level was lower in CI-AKI patients than in non-CI-AKI patients (3.72 ± 0.88 pmol/L vs 4.01 ± 0.80 pmol/L, P < 0.001). Compared with those at the lowest quartile of FT3, the patients at quartiles 2–4 had a higher risk of CI-AKI respectively (P for trend = 0.005). The risk of CI-AKI increased by 17.7% as FT3 level decreased by one unit after PS-matching analysis (odds ratio: 0.823; 95% CI: 0.685–0.988, P = 0.036). After a median of 31 days of follow-up (interquartile range: 30–35 days), 78 patients died, including 72 cardiogenic deaths and 6 non-cardiogenic deaths, with more deaths in the CI-AKI group than in the non-CI-AKI group (53 vs 25, P < 0.001). Kaplan–Meier survival analysis showed that patients at a lower FT3 quartile achieved a worse survival before and after matching.ConclusionLower FT3 may increase the risk of CI-AKI and 1-month mortality in AMI patients.

Incidence and Risk Factors of Contrast-Induced Acute Kidney Injury in Sudanese Patients Undergoing Coronary Angiography: A Descriptive Prospective Study.

Background: Contrast-induced acute kidney injury (CI-AKI) has been reported to be the third most common cause of hospital-acquired acute kidney injury (AKI) and is associated with significant morbidity and mortality.Objectives: This study aimed to assess the incidence and risk factors of CI-AKI in Sudanese patients undergoing coronary angiography.Methods: The study was a descriptive, prospective, hospital-based study conducted at Alshaab Hospital between January and April 2019. A total of 163 patients undergoing coronary angiography were enrolled, and a checklist was used to collect data. Chi-square and regression analyses were performed to identify the risk factors of CI‑AKI. CI‑AKI was defined as a rise in serum creatinine ≥25% above baseline within three days after percutaneous coronary angiography (PCA).Results: CI‑AKI incidence in patients undergoing coronary angiography was 31.9% (52/163). Among independent variables, diabetes mellitus, the type of coronary angiography, and the volume of contrast medium were statistically significantly (p-value ˂ 0.05) associated with CI-AKI development. Logistic analysis showed that diabetes (odds ratio (OR): 15.2; 95% CI: 6.771-33.974; p = 0.001), percutaneous coronary intervention (PCI) (OR: 2.4; 95% CI: 1.168-4.901; p = 0.017), and the volume of contrast medium (OR 2.1; 95% CI: 1.440-3.054; p = 0.001) were independent predictors correlated to CI‑AKI development.Conclusion: The incidence of CI-AKI is 31.9%, and diabetes mellitus, PCI, and high volume of contrast medium are associated with a higher risk of CI-AKI in patients undergoing coronary angiography.

Continuous use of metformin in patients receiving contrast medium: what is the evidence? A systematic review and meta-analysis.

Substantial inconsistencies exist in current guidelines regarding recommendations of metformin usage with the administration of a contrast medium. We aimed to perform a meta-analysis to determine whether the risks of contrast-induced acute kidney injury (CI-AKI) and lactic acidosis increase with metformin use in diabetic patients receiving a contrast medium. Studies were retrieved from databases from inception to May 15, 2021. Studies that compared the outcomes of using metformin with not using metformin during contrast medium administration were included. The primary outcomes were incidence of CI-AKI and lactic acidosis. The secondary outcomes were renal function changes from baseline. Data analysis was using risk ratio (RR) for dichotomous outcomes and mean differences (MD) with 95% confidence intervals (CI) for continuous outcomes. Analyses of two randomized controlled trials and four retrospective cohorts examining a total of 1459 patients revealed no significant differences in the incidence of CI-AKI (RR = 1.08; 95% CI, 0.72 to 1.63) and in changes in renal function measurements (serum creatinine: MD = 0.00mg/dL, 95% CI, - 0.05 to 0.05; estimated glomerular filtration rate: MD = 0.22, 95% CI, - 2.47 to 2.91) after contrast medium administration between patients using and not using metformin. There is no evidence that continuing metformin during contrast medium administration is associated with a higher risk of CI-AKI, lactic acidosis, or renal function deterioration compared to patients who discontinued metformin or who were not metformin users. The limited quality of the included studies may compromise the strength of evidence provided in this meta-analysis. There is no need to discontinue metformin either before or after intravenous contrast medium exposure in patients with eGFR > 30mL/min/1.73 m2. In patients receiving intra-arterial contrast medium with first-pass renal exposure, there is no need to withhold metformin if eGFR is above 60mL/min/1.73 m2. For patients who have an eGFR level between 30 and 60mL/min/1.73 m2 and are receiving intra-arterial contrast medium with first-pass renal exposure, no case of lactic acidosis was observed based on present data, but further evidence is needed to make a strong suggestion regarding its safety.

Comparative analysis of four established risk scores for predicting contrast induced acute kidney injury after primary percutaneous coronary interventions.

This study aimed to compare Mehran Risk Score (MRS) with three well -known scoring systems namely CHA2DS2-VASc score, Canada Acute Coronary Syndrome Risk Score (C-ACS), and Thrombolysis in Myocardial Infarction risk index (TRI) to predict the contrast-induced acute kidney injury (CI-AKI) after primary percutaneous coronary intervention (PCI). CI-AKI is a common complication after primary PCI associated with an adverse prognosis. In this study consecutive patients of primary PCI were included. Patients with chronic kidney diseases, exposure to the contrast medium within the past 7days, and Killip class IV at presentation were excluded. MRS along with three risk scores namely CHA2DS2-VASc, C-ACS, and TRI were calculated for all patients and CI-AKI was defined as either 0.5mg/dL or 25% relative increase in post-procedure serum creatinine. The area under the curve (AUC) curve was reported. Post primary PCI CI-AKI was observed in 63 (9.1%) patients out of 691 patients. The AUC was 0.745 [0.679-0.810] for MRS, 0.725 [0.662-0.788] for CHA2DS2-VASc, 0.671 [0.593-0.749] for C-ACS, and 0.734 [0.674-0.795] for TRI. Sensitivity and specificity were 61.9% [48.8-73.8%] and 76.0% [72.4-79.3%] for MRS≥6.5, 66.7% [53.7-78.0%] and 66.7% [62.9-70.4%] for CHA2DS2-VASc≥2, 52.4% [39.4-65.1%] and 79.9% [76.6-83.0%] for C-ACS≥1, and 87.3% [76.5-94.4%] and 49.2% [45.2-53.2%] for TRI≥16 respectively. The MRS has shown higher discriminating power than CHA2DS2-VASc, C-ACS, and TRI. However, the TRI can be of good value in clinical practice due to its simplicity and high sensitivity in detecting patients at higher risk of CI-AKI after primary PCI.

Usefulness of Adding Pre-procedural Glycemia to the Mehran Score to Enhance Its Ability to Predict Contrast-induced Kidney Injury in Patients Undergoing Percutaneous Coronary Intervention Development and Validation of a Predictive Model

The Mehran score is the most widely accepted tool for predicting contrast-induced acute kidney injury (CI-AKI), a major complication of percutaneous coronary intervention (PCI). Similarly, abnormal fasting pre-procedural glycemia (FPG) represents a modifiable risk factor for CI-AKI, but it is not included in current risk models for CI-AKI prediction. We sought to analyze whether adding FPG to the Mehran score improves its ability to predict CI-AKI following PCI. We analyzed 671 consecutive patients undergoing PCI (age 69 [63,75] years, 23% females), regardless of their diabetic status, to derive a revised Mehran score obtained by including FPG in the original Mehran score (Derivation Cohort). The new risk model (GlyMehr) was externally validated in 673 consecutive patients (Validation Cohort) (age 69 [62,76] years, 21% females). In the Derivation Cohort, both FPG and the original Mehran score predicted CI-AKI (AUC 0.703 and 0.673, respectively). The GlyMehr score showed a better predictive ability when compared with the Mehran score both in the Derivation Cohort (AUC 0.749, 95%CI 0.662 to 0.836; p=0.0016) and the Validation Cohort (AUC 0.848, 95%CI, 0.792 to 0.903; p=0.0008). In the overall population (n=1344), the GlyMehr score confirmed its independent and incremental predictive ability regardless of diabetic status (p ≤0.0034) or unstable/stable coronary syndromes (p ≤0.0272). In conclusion, adding FPG to the Mehran score significantly enhances our ability to predict CI-AKI. The GlyMehr score may contribute to improve the clinical management of patients undergoing PCI by identifying those at high risk of CI-AKI and potentially detecting modifiable risk factors.

Intravascular ultrasound-guided zero-contrast percutaneous coronary intervention: The next frontier in coronary interventions

Chronic kidney disease (CKD), diabetes mellitus, older age, acute coronary syndrome, and cardiogenic shock are the common predisposing factors for contrast-induced acute kidney injury (CI-AKI) after percutaneous coronary intervention (PCI). Apart from intravenous normal saline administration, other measures to prevent CI-AKI have not been consistently beneficial. More recently, intravascular ultrasound (IVUS)-guided zero-contrast PCI has emerged as an important method to prevent CI-AKI in experienced centers. Technical expertise in complex PCI and meticulous analysis of IVUS are required for this procedure. In this review, the authors have described the basic details of the steps involved in this technique. The authors believe that clinical implementation of this technique has the potential for mortality benefit in patients who are at high risk of CI-AKI.

A hospital-based study on risk factors and outcomes of Contrast Induced Acute Kidney Injury (CI-AKI)

Background: Contrast-induced acute kidney injury (CI-AKI) is one of the most common causes of hospital-acquired AKI. This study was aimed to analyse the incidence of CI-AKI and associated risk factors in hospitalized patients undergoing CT or Catheter related contrast based procedures. Materials and Methods: This cross-sectional observational study was conducted between September 2016 and August 2018. Hospitalized patients of either sex, aged >18 years scheduled for contrastenhanced computed tomography (CECT), peripheral angiography (PAG), percutaneous transluminal coronary angioplasty (PTCA), or coronary angiography (CAG), with eGFR >30 were evaluated for CIAKI after excluding other causes of AKI. Results: A total of 300 patients were enrolled, of which 266 patients completed the study (CECT/PAG, n=138; PTCA/CAG, n=128). The mean age of the patients was 45.85 15.14 years and the majority of patients were males (n=164, 61.6%). The incidence of CI-AKI was 15.6% (n=41). A total of 28.8% of patients with diabetes and 31.1% patients aged >60 years developed CI-AKI. Overall, the increasing contrast volume significantly (p=0.002) increased the incidence of CI-AKI. The incidence of CI-AKI in patients mild renal dysfunction increased significantly (from 5.5% at Conclusion: Results showed that radio-contrast related procedure carries a significant risk of nephropathy and patients with diabetes, pre-existing renal dysfunction, and advanced age are at higher risk of CI-AKI. Keywords: Chronic kidney disease contrast-induced acute kidney injury contrast media estimated glomerular filtration rate.

Results of the multicenter, prospective, randomised STRENGTH (Study To evaluate the use of RENalGuard to proTect patients at High risk of acute kidney injury) study

Abstract Aim Radio-contrast agents are widely used in coronary, peripheral and structural interventions. Use of these iodine-containing agents can be associated with contrast-induced acute kidney injury (CI-AKI) that can cause substantial morbidity and mortality. The RenalGuard system induces a forced diuresis with a matched hydration and has been shown beneficial in patients requiring coronary angiogram and PCI. Methods STRENGTH is a prospective, randomised (1:1), open-labeled, parallel-group, multicenter (10 centers in Germany and France) study where patients at high risk of CI-AKI were randomly assigned to RenalGuard® therapy or conventional strategy including preventive hydration before complex percutaneous cardiovascular intervention (PCI, peripheral and structural). In the RenalGuard arm, matched fluid replacement was started 60 minutes pre-procedure and maintained for up to 4 hours afterwards. Patients were given an initial i.v. bolus of up to 250 ml of normal saline over 30 minutes and then an i.v. bolus of furosemide (0.5 mg/kg). To be enrolled, patients had to have moderate to severe renal failure (defined as 15≤eGFR≤40 mL/min/m2) and a high-volume contrast requiring cardiovascular procedure (estimated contrast volume&amp;gt;3 times eGFR value). The main exclusion criterion was administration of iodine contrast media within 5 days before index procedure. The primary endpoint was CI-AKI defined as an increase in sCr ≥0.3 mg/dL or an increase of 25% of basal value or requiring dialysis within 5 days after procedure. The primary analysis for efficacy is performed in a modified intention-to-treat basis. The trial was designed and monitored by an independent CRO (Cardiovascular European Research Center, CERC, Massy, France). Results A total of 259 patients aged 79.1±8.8 yrs were included in the study. Among them, 129 were assigned to RenalGuard therapy and 130 to preventive saline hydration. Their mean baseline eGFR was 32 (25; 37) vs. 33 (25; 39) mL/min/m2, respectively (p=0.88). Total fluid intake volume within 24hrs before the procedure was 2383±1146 vs. 1386±842mL, respectively (p&amp;lt;0.0001). Procedure type was complex PCI (48%), TAVI (25%), peripheral intervention (18%), other structural intervention (9%) with no difference between groups (p=0.56). The total amount of contrast used for the procedure was 116.3±68.2mL in the RenalGuard arm vs. 104.1±56.7 mL in the conventional arm (p=0.26). A staged procedure was performed in 24 patients, including 16 in the RenalGuard and 8 in the control arm with a mean interval from the first intervention of 43±29 days and 24±19 days, respectively. For this second procedure, the total amount of contrast was 80±59 vs. 87±73mL. Conclusion The primary and secondary endpoints of the Study To evaluate the use of RENalGuard to proTect patients at High risk of CI-AKI comparing RenalGuard therapy to conventional hydration in 259 patients requiring complex percutaneous cardiovascular intervention will be presented. Funding Acknowledgement Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): CERC

Avoiding the emergence of contrast-induced acute kidney injury in acute coronary syndrome: routine hydration treatment.

Patients with acute coronary syndrome (ACS) have about a three-fold risk for developing contrast-induced acute kidney injury(CI-AKI). Investigating studies on routine hydration therapy have frequently included patients with stable coronary artery disease and high risk of CI-AKI [estimated glomerular filtration rate (eGFR) < 60 ml/min]. However, data on routine hydration treatment in non-ST segment elevation myocardial infarction (NSTEMI) patients with eGFR ≥60 ml/min are insufficient. We aimed to investigate the association between routine hydration therapy and CI-AKI development in NSTEMI patients at low risk for nephropathy. We randomly assigned a total of 401 NSTEMI patients to two groups: the routine hydration group (198 patients) and the nonhydration group (control group) (203 patients). Intravenous hydration with isotonic saline (1 ml/kg/h, 0.9% sodium chloride) was given for 3-12 h before and 24 h after contrast exposure to the hydration group. CI-AKI was defined as the increase in serum creatinine values 0.5 mg/dl or 25% between 48 and 72 h after the invasive procedures. In our study, the incidence of CI-AKI development in the routine hydration group (7.1%) was significantly lower than in the nonhydration group (14.1%) (P: 0.02). This study revealed that older age, amount of contrast media, and routine hydration were independent risk factors for developing CI-AKI (P < 0.01, P: 0.04, P < 0.01, respectively). We found that preprocedural and postprocedural intravenous hydration therapy reduces the development of CI-AKI in patients with NSTEMI at low risk for CI-AKI. We suggest administering routine hydration therapy in all ACS patients regardless of eGFR values.

A preprocedural risk score predicts acute kidney injury following primary percutaneous coronary intervention

Reliable preprocedural risk scores for the prediction of Contrast-Induced Acute Kidney Injury (CI-AKI) following Percutaneous Coronary Intervention (pPCI) in patients with ST-elevation myocardial infarction (STEMI) are lacking. Aim of this study was to derive and validate a preprocedural Risk Score in this setting. Two prospectively enrolled patient cohorts were used for derivation and validation (n=3,736). CI-AKI was defined as creatinine increase ≥0.5mg/dl <72 h postpPCI. Odds ratios from multivariable logistic regression model were converted to an integer, whose sum represented the Risk Score. Independent CI-AKI predictors were: diabetes, Killip class II-III (2 points each), age > 75 years, anterior MI (3 points), Killip class IV (4 points), estimated GFR< 60 ml/min/1.73m2 (5 points). The Risk Score c-statistic was 0.84 in both cohorts. Compared with patients with Risk Score ≤ 4, the relative risks of CI-AKI among patients scoring 5-9 were 6.2 (derivation cohort) and 7.1 (validation cohort); among patients scoring ≥10, 19.8, and 21.4, respectively. Among STEMI patients, a simple preprocedural Risk Score accurately and reproducibly predicted the risk of CI-AKI, identifying ¼ of patients with a seven-fold risk and 1/10 of patients with a 20-fold risk. This knowledge may help tailored strategies, including delaying revascularization of nonculprit vessels in patients at high risk of CI-AKI.

Risk factors and incidence of contrast-induced acute kidney injury associated with diagnostic or interventional coronary angiography

Background and Aims: Coronary angiography/ interventions depend on iodinated contrast media (CM) and consequently pose risk of contrast-induced acute kidney injury (CI-AKI). This is an important complication that accounts for a significant number of cases of hospital-acquired kidney injury, with adverse effects on prognosis and health care. This study aimed to assess incidence and evaluate risk factor CI-AKI associated with diagnostic or interventional coronary angiography.&#x0D; Methods: A prospective cross sectional observational hospital based study was conducted. All patients undergoing percutaneous coronary angiography in Manipal Teaching Hospital from May 1, 2019 to April 31, 2020 were included in this study. Appropriate statistical tests were used to analyse results and P &lt;0.05 was considered statistically significant.&#x0D; Results: We evaluated a total of 155 patients. Among them, 90 (58%) were male and 65 (42%) female. The mean age of patients was 62.74 ± 13.9 years. Overall incidence of contrast induced acute kidney injury was 15.48%. CI-AKI was observed to be more common in patient with advance age and diabetes. Apart from advance age and diabetes, none of the other conventional risk factors such as hypertension, anaemia, volume of contrast, baseline chronic kidney disease found to have a significant association with incidence of CI-AKI. None of the patients in our study required renal replacement therapy, and there was no mortality.&#x0D; Conclusion: The overall incidence of CI-AKI after coronary intervention in this study is high. Patients with advance age and diabetes were at high risk of CI-AKI.

Contrast medium induced acute kidney injury: a narrative review.

Contrast-induced acute kidney injury (CI-AKI) is the third leading cause of hospital-acquired acute kidney injury. It is more commonly observed following intra-arterial administration of iodinated contrast media (CM) for cardiac procedures in patients with pre-existing chronic kidney disease (CKD), and is associated with increased short- and long-term morbidity and mortality. This review investigates the key current evidence on CI-AKI definition, epidemiology and pathogenesis, as a basis for recommending preventive measures that can be implemented in clinical practice. An extensive literature search was performed to identify the relevant studies describing the epidemiology, pathogenesis, outcome and prevention of CI-AKI. Pre-existing CKD, intra-arterial administration and CM volume are the most important risk factors for CI-AKI. Since risk factors for CI-AKI are well defined, and the timing of renal insult is known, patients should be carefully stratified before the administration of CM, in order to reduce the negative impact of modifiable risk factors on renal function. The intravenous administration of moderate amounts of isotonic saline solution or bicarbonate solution still represents the principal intervention with documented and acceptable effectiveness for CI-AKI prevention. More data are needed on aggressive volume expansion strategies along with diuretics, targeting forced diuresis with high urinary output. The role of antioxidant agents remains controversial, and only moderate evidence exists in favour of N-acetylcysteine. Statins could contribute to reducing the incidence of CI-AKI, although their mechanism of action is not fully ascertained. No robust data demonstrate a reduction of CI-AKI incidence by peri-procedural hemodialysis/hemofiltration; renal replacement therapies may carry instead unnecessary risks. Remote ischemic preconditioning might represent a simple, non-invasive and cost effective preventive measure for CI-AKI prevention, but few data are currently available about its clinical application in patients at high risk of CI-AKI.

Risk of contrast-induced acute kidney injury in ST-elevation myocardial infarction patients undergoing multi-vessel intervention-meta-analysis of randomized trials and risk prediction modeling study using observational data.

Ascertaining risk of contrast induced acute kidney injury (CI-AKI) in ST-segment elevation myocardial infarction (STEMI) patients undergoing multi-vessel percutaneous coronary intervention (MV-PCI). Complete revascularization may improve outcomes in STEMI patients with multi-vessel disease. However, a practice of MV-PCI may be associated with a higher risk of CI-AKI. We aimed to evaluate the risk of CI-AKI in patients with STEMI and MV-PCI and examine the accuracy of a validated risk score. We searched PubMed, Cochrane Library, EMBASE, EBSCO, Web of Science, and CINAHL databases from inception through August 31, 2016 for randomized studies comparing CI-AKI rates with MV-PCI and infarct-related artery (IRA) only PCI during index hospitalization. A random effects model was used to estimate the risk ratio (RR) and respective 95% confidence intervals (CI). We queried the Nationwide Inpatient Sample (NIS) to assess the ability of the Mehran risk score to accurately predict the incidence of CI-AKI in patients undergoing MV-PCI. Four randomized studies (N = 1,602) were included in the final analysis. The risk of CI-AKI was low and no difference was observed with MV-PCI (1.45%) compared with IRA-only (1.94%) (RR 0.73, 95% CI 0.34-1.57; P = 0.57). From 2009 to 2012, excluding shock, there were 11,454 MV-PCI for STEMI patients in the NIS. The Mehran risk score accurately discriminated 78% of the patients who developed CI-AKI in this cohort (c-statistic of 0.78, P = 0.002). MV-PCI in STEMI is not associated with a higher risk of CI-AKI and the Mehran risk score can identify patients at higher risk for this complication. © 2017 Wiley Periodicals, Inc.

Short-term rosuvastatin therapy prevents contrast-induced acute kidney injury in female patients with diabetes and chronic kidney disease: a subgroup analysis of the TRACK-D study.

Female patients are at higher risk of contrast-induced acute kidney injury (CIAKI) compared to males. In the multicenter, prospective, TRACK-D study, short-term rosuvastatin has proven effectively reduce CIAKI in patients with type 2 diabetes mellitus and stage 2-3 chronic kidney disease (CKD). This study aimed to explore the efficacy of rosuvastatin in the female TRACK-D population. This study was a gender-based analysis of 2,998 patients (1,044 females) enrolled in the TRACK-D study and were randomized to short-term (2 days before and 3 days after procedure) rosuvastatin therapy or standard of care. The primary outcome was the incidence of CIAKI and the secondary outcome was a composite of death, dialysis/hemofiltration or worsening heart failure at 30 days. CIAKI incidence was comparable between male and female patients in the overall study population (2.5% vs. 3.4%, P=0.165) and in the rosuvastatin group (2.4% vs. 2.1%, P=0.72), while it was higher in females than in males in the control group (3.1% vs. 5.3%, P=0.04). Female gender was an independent risk factor of CIAKI [odds ratio (OR) =1.65; 95% confidence interval (CI), 1.03-2.63; P=0.036]. Rosuvastatin treatment vs. control lowered CIAKI rate in females [2.1% vs. 5.3%; relative risk (RR) =0.39; 95% CI, 0.19-0.77; number needed to treat (NNT) =31], particularly among those with CKD stage 2 (1.2% vs. 4.1%, P=0.011). Secondary outcome incidence was similar for females in the rosuvastatin and control groups (3.7% vs. 4.9%, P=0.37). Compared to males, untreated females with diabetes mellitus and CKD had a higher risk of CIAKI, which can be reduced by short-term rosuvastatin treatment.

Elevated serum fibrinogen levels and risk of contrast-induced acute kidney injury in patients undergoing a percutaneous coronary intervention for the treatment of acute coronary syndrome.

Contrast-induced acute kidney injury (CI-AKI) is a common complication of diagnostic and therapeutic catheterizations, especially in the setting of acute coronary syndrome (ACS). Fibrinogen is a well-known cardiovascular risk factor. We evaluated whether serum fibrinogen level is associated independently with CI-AKI in patients with ACS who underwent a percutaneous coronary intervention (PCI). Patients (n=710, aged 61 ± 13, 69% men) were classified into two groups: CI-AKI and non-CI-AKI. CI-AKI was defined as an increase of at least 0.5 mg/dl or at least 25% in the serum creatinine level within 72 h following PCI. CI-AKI occurred in 75 (10.6%) patients. We found significantly higher serum fibrinogen levels in patients who developed CI-AKI than in those who did not (498 ± 152 vs. 386 ± 96 mg/dl, P<0.001). Multivariate logistic regression analysis showed that serum fibrinogen level (odds ratio 1.006, 95% confidence interval 1.003-1.009, P<0.001), age, glomerular filtration rate, female sex, and white blood cell count were correlated with the development of CI-AKI. Serum fibrinogen level is associated independently with a higher risk of CI-AKI in patients with ACS undergoing PCI.

Limb ischemic preconditioning protects against contrast-induced acute kidney injury in rats via phosphorylation of GSK-3β

Contrast-induced acute kidney injury (CI-AKI) resulting from the use of intravascular iodinated contrast media for diagnostic and interventional cardiovascular procedures is associated with substantial morbidity and mortality. Despite preventative measures intended to mitigate the risk of CI-AKI, there remains a need for a novel and effective therapeutic approach. Limb ischemic preconditioning (LIPC), where short-term ischemia/reperfusion is applied to an arm prior to administration of the contrast agent, has been shown in several trials to preserve renal function in patients at high risk for CI-AKI. However, the underlying mechanism by which this procedure provides renoprotection against contrast media insults is not known. Here, we explored the molecular mechanism(s) of LIPC-induced protection of the kidneys from CI-AKI, particularly the role of phosphorylated glycogen synthase kinase-3β (GSK-3β). We used a novel CI-AKI model consisting of 5/6 nephrectomized (NE) rats at 6 weeks after the ablative surgery. LIPC- or sham-treated rats were administered iohexol (10 ml/kg, 3.5 gI) via the tail vein. The results showed that LIPC protected the kidneys against iohexol-induced injury. This protective effect was accompanied by the attenuation of renal dysfunction, tubular damage, apoptosis, mitochondrial swelling, oxidative stress, and inflammation. Furthermore, LIPC-induced renoprotection was blocked via treatment with inhibitors of PI3K (wortmannin or LY294002), but not ERK (U0126 or PD98059). LIPC also increased the protein expression levels of phospho-Akt, phospho-GSK-3β, and nuclear Nrf2, and decreased the levels of nuclear NF-κB. A specific GSK-3β inhibitor (SB216763) mimicked this effect of LIPC, by inhibiting the opening of the mitochondrial permeability transition pore and reducing the levels of oxidative stress and inflammation via activation of Nrf2 and suppression of NF-κB. The above results demonstrate that LIPC induces protection against CI-AKI, making this procedure a promising strategy for preventing CI-AKI. In particular, this renoprotective effect involves the phosphorylation of GSK-3β.

Clinical Predictors of Contrast-Induced Acute Kidney Injury in Patients Undergoing Emergency Versus Elective Percutaneous Coronary Intervention

To evaluate the incidence and clinical predictors of contrast-induced acute kidney injury (CI-AKI) in patients with ST-segment elevation myocardial infarction (STEMI), unstable angina pectoris/non-STEMI (UAP/NSTEMI), and stable AP (SAP) undergoing percutaneous coronary intervention (PCI). We enrolled 1,954 patients (SAP, n=1,222; UAP/NSTEMI, n=277; STEMI, n=455) who underwent PCI. Patients were categorized according to contrast media volume/estimated glomerular filtration rate ratio (CV/eGFR low: <2.0, mid: 2.0-2.9, high: ≥3.0). CI-AKI was defined as an increase in serum creatinine of 0.5mg/dl or 25% within 1 week from contrast-medium injection. The incidence of CI-AKI was highest among the STEMI patients (SAP, 4.24%; UAP/NSTEMI, 10.7%; STEMI, 16.1%, P<0.01). Significant predictors of CI-AKI were emergency PCI (odds ratio [OR] 3.70; 95% confidence interval [CI] 2.55-5.37; P<0.001), ejection fraction <40% (OR 2.04; 95% CI 1.24-3.36; P=0.005), and hemoglobin <10g/dl (OR 0.02; 95% CI 1.17-4.55; P=0.02) after multivariate logistic regression analysis. In the SAP group, a CV/eGFR ratio ≥3.0 was a significant predictor of CI-AKI (P=0.048), but not in UAP/NSTEMI and STEMI patients. UAP/NSTEMI and STEMI patients undergoing emergency PCI were at high risk for CI-AKI regardless of CV/eGFR ratio. Minimizing the dose of contrast medium based on eGFR might be valuable in reducing the risk of CI-AKI in SAP patients.

A simple preprocedural score for risk of contrast‐induced acute kidney injury after percutaneous coronary intervention

To develop a simple scoring system based on preprocedural clinical features that is capable of predicting contrast-induced acute kidney injury (CI-AKI) before percutaneous coronary intervention (PCI). CI-AKI is associated with increased in-hospital morbidity and mortality, prolonged hospitalization, and long-term renal impairment. Although several scoring methods have been developed to determine risk of CI-AKI, no simple scoring method based on PCI preprocedural clinical features yet exists for Chinese patients. A total of 2,500 Chinese patients were randomly and retrospectively assigned in a 3:2 manner to create a training and validation dataset, respectively. CI-AKI was defined as an increase of ≥25% or ≥0.5 mg/dL serum creatinine within 5 days after PCI. Preprocedural clinical variables showing independent correlation to CI-AKI were used to derive the risk score from the training dataset and then subsequently tested in the validation dataset. The odds ratios from multivariate logistic regression were used to assign a weighted integer to age ≥70 years = 4, history of myocardial infarction = 5, diabetes mellitus = 4, hypotension = 6, left ventricular ejection fraction ≤45% = 4, anemia = 3, creatinine clearance rate <60 mL/min = 7, decreased high-density lipoprotein <1 mmol/L= 3, and urgent PCI = 3. Summation of the integers represented the total risk score. The overall incidence of CI-AKI in the training dataset was 16.4% [246/1500; 5.4% for low (≤7) and 61.3% for very high (≥17) risk scores]. The rates of CI-AKI, 1-year dialysis, and 1-year mortality increased significantly with each group (Cochran-Armitage test of trend, P < 0.001). The risk score facilitated appropriate classification of patients with low and high risk for CI-AKI after PCI in the validation dataset (c-statistic = 0.82). Risk classification based on the most significantly correlated parameters is useful for predicting CI-AKI before contrast exposure. The simple preprocedural score showed excellent predictive ability for identifying patients at high risk of nephropathy and those with deteriorative prognosis after PCI.

Early High-Dose Rosuvastatin for Contrast-Induced Nephropathy Prevention in Acute Coronary Syndrome: Results From the PRATO-ACS Study (Protective Effect of Rosuvastatin and Antiplatelet Therapy On Contrast-Induced Acute Kidney Injury and Myocardial Damage in Patients With Acute Coronary Syndrome)

This study sought to determine if in addition to standard preventive measures on-admission, high-dose rosuvastatin exerts a protective effect against contrast-induced acute kidney injury (CI-AKI).Patients with acute coronary syndrome (ACS) are at high risk for CI-AKI, and the role of statin pre-treatment in preventing renal damage remains uncertain.Consecutive statin-naïve non-ST elevation ACS patients scheduled to undergo early invasive strategy were randomly assigned to receive rosuvastatin (40 mg on admission, followed by 20 mg/day; statin group n = 252) or no statin treatment (control group n = 252). CI-AKI was defined as an increase in creatinine concentration of ≥0.5 mg/dl or ≥25% above baseline within 72 h after contrast administration.The incidence of CI-AKI was significantly lower in the statin group than in controls (6.7% vs. 15.1%; adjusted odds ratio: 0.38; 95% confidence interval [CI]: 0.20 to 0.71; p = 0.003). The benefits against CI-AKI were consistent, even applying different CI-AKI definition criteria and in all the pre-specified risk categories. The 30-day incidence of adverse cardiovascular and renal events (death, dialysis, myocardial infarction, stroke, or persistent renal damage) was significantly lower in the statin group (3.6% vs. 7.9%, respectively; p = 0.036). Moreover, statin treatment given on admission was associated with a lower rate of death or nonfatal myocardial infarction at 6 month follow-up (3.6% vs. 7.2%, respectively; p = 0.07).High-dose rosuvastatin given on admission to statin-naïve patients with ACS who are scheduled for an early invasive procedure can prevent CI-AKI and improve short-term clinical outcome. (Statin Contrast Induced Nephropathy Prevention [PRATO-ACS]; NCT01185938).

Remote Ischemic Pre-Conditioning Alleviates ContrastInduced Acute Kidney Injury in Patients With Moderate Chronic Kidney Disease

Although remote ischemic preconditioning (RIPC) is shown to preserve kidney function in patients at high risk of contrast-induced acute kidney injury (CI-AKI), the effect in patients at low-moderate risk remains unknown. The preventive effects of RIPC in patients not at high risk of CI-AKI were examined, and biomarkers with anticipated roles in renal protection via RIPC investigated. Sixty patients who had moderate chronic kidney disease and who underwent angiography were randomly assigned to the control (n=30) or RIPC (intermittent arm ischemia, n=30) group. The baseline characteristics in the 2 groups did not differ significantly. CI-AKI was evaluated by measuring urinary liver-type fatty acid-binding protein (L-FABP). Biomarkers were measured before and 24 and 48 h after angiography. Twenty-four hours after angiography, the percent change in urinary L-FABP level in the RIPC group was significantly smaller than in the control group (41.3±15.6 vs. 159±34.1%, P=0.003). L-FABP-based CI-AKI developed in 8 control patients (26.9%) vs. only 2 patients in the RIPC group (7.7%), suggesting that RIPC prevents CI-AKI. Factors contributing to CI-AKI were analyzed. Neither high-sensitivity C-reactive protein nor pentraxine-3 level differed significantly between the 2 groups, while the percent change in asymmetrical dimethy larginine (ADMA) level and blood derivatives of reactive oxidative metabolite levels were significantly smaller in the RIPC group. RIPC alleviates CI-AKI in patients at low-moderate risk. This effect might be mediated partly by decreasing oxidative stress and plasma ADMA level.