Predictors of outcomes of contrast-induced acute kidney injury after percutaneous coronary intervention in patients with chronic kidney disease

High-mobility group box 1 and its related receptors: potential therapeutic targets for contrast-induced acute kidney injury

Percutaneous coronary intervention (PCI) is a crucial diagnostic and therapeutic approach for coronary heart disease. Contrast agents' exposure during PCI is associated with a risk of contrast-induced acute kidney injury (CI-AKI). CI-AKI is characterized by a sudden decline in renal function occurring as a result of exposure to intravascular contrast agents, which is associated with an increased risk of poor prognosis. The pathophysiological mechanisms underlying CI-AKI involve renal medullary hypoxia, direct cytotoxic effects, endoplasmic reticulum stress, inflammation, oxidative stress, and apoptosis. To date, there is no effective therapy for CI-AKI. High-mobility group box 1 (HMGB1), as a damage-associated molecular pattern molecule, is released extracellularly by damaged cells or activated immune cells and binds to related receptors, including toll-like receptors and receptor for advanced glycation end product. In renal injury, HMGB1 is expressed in renal tubular epithelial cells, macrophages, endothelial cells, and glomerular cells, involved in the pathogenesis of various kidney diseases by activating its receptors. Therefore, this review provides a theoretical basis for HMGB1 as a therapeutic intervention target for CI-AKI.

Absolute and relative GFR and contrast medium dose/GFR ratio: cornerstones when predicting the risk of acute kidney injury

Glomerular filtration rate (GFR) is considered the best overall index of kidney function in health and disease and its use is recommended to evaluate the risk of iodine contrast medium-induced acute kidney injury (CI-AKI) either as a single parameter or as a ratio between the total contrast medium dose (gram iodine) and GFR. GFR may be expressed in absolute terms (mL/min) or adjusted/indexed to body surface area, relative GFR (mL/min/1.73 m2). Absolute and relative GFR have been used interchangeably to evaluate the risk of CI-AKI, which may be confusing and a potential source of errors. Relative GFR should be used to assess the GFR category of renal function as a sign of the degree of kidney damage and sensitivity for CI-AKI. Absolute GFR represents the excretion capacity of the individual and may be used to calculate the gram-iodine/absolute GFR ratio, an index of systemic drug exposure (amount of contrast medium in the body) that relates to toxicity. It has been found to be an independent predictor of AKI following percutaneous coronary angiography and interventions but has not yet been fully validated for computed tomography (CT). Prospective studies are warranted to evaluate the optimal gram-iodine/absolute GFR ratio to predict AKI at various stages of renal function at CT. Only GFR estimation (eGFR) equations based on standardized creatinine and/or cystatin C assays should be used. eGFRcystatin C/eGFRcreatinine ratio < 0.6 indicating selective glomerular hypofiltration syndrome may have a stronger predictive power for postcontrast AKI than creatinine-based eGFR. CLINICAL RELEVANCE STATEMENT: Once the degree of kidney damage is established by estimating relative GFR (mL/min/1.73 m2), contrast dose in relation to renal excretion capacity [gram-iodine/absolute GFR (mL/min)] may be the best index to evaluate the risk of contrast-induced kidney injury. KEY POINTS: • Relative glomerular filtration rate (GFR; mL/min/1.73 m2) should be used to assess the GFR category as a sign of the degree of kidney damage and sensitivity to contrast medium-induced acute kidney injury (CI-AKI). • Absolute GFR (mL/min) is the individual's actual excretion capacity and the contrast-dose/absolute GFR ratio is a measure of systemic exposure (amount of contrast medium in the body), relates to toxicity and should be expressed in gram-iodine/absolute GFR (mL/min). • Prospective studies are warranted to evaluate the optimal contrast medium dose/GFR ratio predicting the risk of CI-AKI at CT and intra-arterial examinations.

Clinical Outcomes of Patients with Chronic Kidney Disease Undergoing Percutaneous Coronary Interventions with a Novel Dynamic Coronary Roadmap System

Dynamic coronary roadmap (DCR) is a novel technology that creates a real-time overlay of the coronary arteries in percutaneous coronary intervention (PCI) and has the potential to reduce the contrast volume. However, the efficacy of DCR in terms of clinical outcomes in patients with chronic kidney disease (CKD) remains to be fully elucidated.This single center retrospective study enrolled 275 patients with CKD who underwent PCI, and divided them into a DCR group (n = 124) and Non-DCR group (n = 151). Propensity score matching was performed to minimize the differences in baseline characteristics in 113 patient pairs. The primary endpoint was a composite outcome of all-cause death, hospitalization for heart failure, nonfatal myocardial infarction, or the introductory rate of dialysis within 2 years. The secondary endpoints were contrast medium volume, the incidence of contrast-induced acute kidney injury (CI-AKI), and the introductory rate of dialysis within 2 years.Although there was no significant difference in the success rate (DCR group: 99.1% versus Non-DCR group: 98.2%; P = 0.561), contrast volume (92.20 mL versus 115.97 mL; P = 0.002) was significantly lower in the DCR group. CI-AKI incidence was 0.9% versus 6.2% in the DCR and Non-DCR groups, respectively (P = 0.031). The composite outcome defined as primary endpoint occurred in 10 patients in the DCR group and 20 patients in the Non-DCR group (8.8% versus 17.7%; P = 0.049).From the perspective of acute and long-term clinical outcomes, DCR use may be effective for patients with CKD.

A risk score model of contrast-induced acute kidney injury in patients with emergency percutaneous coronary interventions

Background

The previously built score models of contrast-induced acute kidney injury (CI-AKI) were principally founded on selective percutaneous coronary intervention (PCI) cases. Our study was to form a risk score model of CI-AKI and make a temporal validation in a population who underwent emergency PCIs.

Methods

We included patients who underwent emergency PCIs from 2013 to 2018 and divided them into the derivation and validation cohorts. Logistic regression analysis was harnessed to create the risk model. In this research, we defined CI-AKI as an increase in serum creatinine (SCr) ≥0.5 mg/dL (44.2 μmol/L) above baseline within seven days following exposure to contrast medium.

Results

A total of 3564 patients who underwent emergency PCIs were enrolled and divided into the derivation (2376 cases) and validation cohorts (1188 cases), with CI-AKI incidence of 6.61 and 5.39%, respectively. By logistic analysis, the CI-AKI risk score model was constituted by 8 variables: female (1 point), history of transient ischemic attack (TIA)/stroke (1 point), left ventricular ejection fraction (LVEF) classification (1 point per class), big endothelin-1 (ET-1) classification (1 point per class), estimated glomerular filtration rate (eGFR) classification (1 point per class), intra-aortic balloon pump (IABP) application (1 point), left anterior descending (LAD) stented (1 point), and administration of diuretic (2 points). The patients could be further divided into three groups: low-risk, moderate-risk, and high-risk groups, in accordance with the risk scores of 3–6, 7–10, and ≥11 points, and to the CI-AKI rates of 1.4, 11.9, and 42.6%. The CI-AKI risk score model performed well in discrimination (C statistic = 0.787, 95% CI: 0.731–0.844) and calibration ability, and showed a superior clinical utility.

Conclusion

We developed a simple CI-AKI risk score model which performs well as a tool for CI-AKI prediction in patients who underwent emergency PCIs.

Anemia is associated with increased risk of contrast‑induced acute kidney injury: A Systematic Review and Meta-analysis

Previous studies have identified numerous risk factors of contrast-induced acute kidney injury (CI-AKI) in patients undergoing coronary angiography. However, the association between anemia and CI-AKI remains conflicting. Thus, we conducted a meta-analysis to further clarify the relationship between anemia and CI-AKI. PubMed, EMBASE and Web of Science were systematically searched from inception to June 2020 to identify eligible studies. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the correlation between anemia and CI-AKI. The potential publication bias was estimated using funnel plot and Begg's test. A total of 13 studies (five case-control studies and eight cohort studies) comprising 27,135 patients were included. The pooled results showed that anemia was a significant risk factor of CI-AKI (OR, 1.82; 95% CI, 1.27-2.61). Moreover, the results of subgroup analyses and sensitivity analyses were basically consistent with the overall pooled result. Funnel plot and Begg's test indicated that there existed potential publication bias, but the result of trim and filled analysis showed that the pooled results kept stable after adding 'missing' studies. This meta-analysis suggested that anemia may be correlated with an increased incidence of CI-AKI in patients undergoing coronary angiography. However, our conclusions should be interpreted with caution due to some limitations. Therefore, further high-quality trials should be conducted to confirm our findings.

Midkine as an Early Biomarker of Contrast-induced Acute Kidney Injury in Chronic Kidney Disease Patients Undergoing Percutaneous Coronary Intervention for Acute Coronary Syndrome: A Single-center Prospective Study

Background: Contrast-induced acute kidney injury (CI-AKI), is an important complication of percutaneous coronary intervention (PCI). We aimed to study the role of serum midkine (MK) as an early biomarker of CI-AKI. Methods: We conducted a prospective observational cohort study. It includes 100 chronic kidney disease (CKD) patients with an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73m2. All patients were undergoing PCI for ACS. We measured serum midkine before, 2 and 24 hours after PCI.  Results: The mean age of the patients was 70.32±3.62 years, 74% males. Twenty-seven patients developed CI-AKI. The CI-AKI group has a history of diabetes mellitus (DM) and/or dyslipidemia, history of diuretics, metformin and/or angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers (ACEI/ARBs) use. The CI-AKI patients have low left ventricular ejection fraction (LVEF) (EF < 45%) and low Creatinine Clearance (CrCl) before PCI. The CI-AKI received more contrast volume, had a longer duration of PCI  and had high Mehran risk score after PCI. Comparison between the two studied groups regarding serum MK showed that there was a statistically significant difference regarding serum MK 2 hours after PCI. Receiver operating characteristic (ROC) curve analysis for serum MK showed that serum MK measured 2 hours after PCI was statistically significant to predict CI-AKI. Conclusion: An early Serum MK after PCI can be used as an early predictor of CI-AKI in ACS patients.

C-Reactive Protein/Albumin Ratio Predicts Acute Kidney Injury in Patients With Moderate to Severe Chronic Kidney Disease and Non-ST-Segment Elevation Myocardial Infarction

In this study, we aimed to evaluate the predictive value of admission C-reactive protein/albumin ratio (CAR) for acute kidney injury (AKI) in cases with moderate to severe chronic kidney disease (CKD) not on dialysis who presented with non-ST-segment elevation myocardial infarction (NSTEMI) and underwent coronary angiography (CAG). This cross-sectional and observational study included 420 NSTEMI patients. The study population was categorized based on the CAR tertiles as groups T1, T2, and T3. The primary outcome of the study was AKI development; 92 (21.9%) cases developed AKI. The frequency of AKI was significantly higher in the T3 group compared with the T2 and T1 groups (34% vs 17% vs 14%, P < .001). Age, estimated glomerular filtration rate, contrast media volume, and CAR (odds ratio: 1.36; 95% CI: 1.17-1.57; P < .01) were significant predictors of AKI. In a receiver operating characteristic curve analysis, CAR levels >0.20 predicted AKI development with a sensitivity of 74% and a specificity of 45%. We observed that the CAR may be a promising inflammatory parameter for AKI in NSTEMI patients with moderate to severe CKD after CAG.

Transradial Access for High-Risk Percutaneous Coronary Intervention: Implications of the Risk-Treatment Paradox

[Figure: see text].

Long-term renal outcomes after elective percutaneous coronary intervention in patients with advanced renal dysfunction

The aim of the present study was to evaluate the renal outcomes, including the time course of renal function, after elective PCI in patients with advanced renal dysfunction and to assess the predictors of renal dysfunction progression. This is a subanalysis of a previous observational multicenter study that investigated long-term clinical outcomes in patients with advanced renal dysfunction (eGFR < 30 mL/min/1.73 m²), focusing on 151 patients who underwent elective PCI and their long-term renal outcomes. Renal dysfunction progression was defined as a 20% relative decrease in eGFR at 1 year from baseline or the initiation of permanent dialysis within 1 year. Progression of renal dysfunction at 1 year occurred in 42 patients (34.1%). Among patients with renal dysfunction progression, the decrease of renal function from baseline was not observed at 1 month but after 6 months of the index PCI. Baseline eGFR and serum albumin level were significant predictors of renal dysfunction progression at 1 year. Among 111 patients who had not been initiated on dialysis within 1 year, those with renal dysfunction progression had a significantly higher incidence of dialysis initiation more than 1 year after the index PCI than those with preserved renal function (p < 0.001). Among patients with advanced renal dysfunction who underwent elective PCI, 34.1% showed renal dysfunction progression at 1 year. The decrease in renal function was not observed at 1 month but after 6 months of the index PCI in patients with renal dysfunction progression. Furthermore, patients with renal dysfunction progression had poorer long-term renal outcomes.

Prophylactic hemodialysis following coronary angiography and one-year outcomes in non-dialysis patients with chronic kidney disease: A propensity-matched study

BACKGROUND/PURPOSE

Prophylactic hemodialysis after coronary angiography in patients with chronic kidney disease (CKD) prevents contrast nephropathy; however, the one-year outcomes are unclear. This study aimed to investigate the one-year outcomes of prophylactic hemodialysis against standard treatment in patients with CKD who underwent coronary angiography.

METHODS

A cohort study of 359 patients with CKD, coronary artery disease (CAD), and serum creatinine levels of 176.8-530.4 μmol/L, who were referred for elective coronary angiography was conducted. Propensity score matching identified 118 patient pairs for outcome comparisons. The hemodialysis group underwent prophylactic hemodialysis after coronary angiography, whereas the control group received standard treatment. The study's primary outcome was free from dialysis was considered the primary outcome, whereas the secondary outcome was overall survival. Unadjusted estimates of the probability of free from dialysis and overall survival were computed using Kaplan-Meier survival curves and log-rank tests. Cox proportional-hazards regression models were used in determining the risk factors associated with ESRD and mortality.

RESULTS

During a mean 9.3 months follow-up duration, the hemodialysis group had significantly better free from dialysis (85.6% vs. 64.4%; P = 0.002) and overall survival (85.4% vs. 78.5%; P = 0.008) rates than the control group. Cox proportional-hazards regression analyses of the propensity score-matched patients showed that the hemodialysis group had reduced risks for ESRD and mortality (hazard ratios, 0.32 and 0.48, respectively).

CONCLUSION

Prophylactic Hemodialysis following coronary angiography was associated with reduced ESRD and mortality risks in CKD patients with CAD, who did not routinely undergo dialysis.

Predictors of contrast-induced acute kidney injury in patients with coronary artery disease receiving contrast agents twice within 30 days

BACKGROUND

None of study mentioned about contrast-induced acute kidney injury (CI-AKI) in people who have received contrast agents twice within in a short period of time. This study is trying to identify the predictors.

METHODS

We enrolled 607 patients between Oct. 2010 and Jul. 2015 who received contrast agents twice within 30 days in the Department of Cardiology of the General Hospital of Shenyang Military Region. The primary outcome was CI-AKI within 72 h after contrast agent exposure. Patients were divided into groups A (n = 559) and group B (n = 48) according to whether CI-AKI occurred after the second agent.

RESULTS

Patients in group B (CI-AKI occurred after the second agent) had a more rapid heart rate and more usage of diuretics and digitalis. In group B, CI-AKI occurred more frequently after the first agent. Multivariate logistic regression showed that diuretic (P = 0.006) and intra-aortic balloon pump (IABP) usage (P = 0.012) were independent predictors of CI-AKI after the first agent. Angiotensin-converting enzyme inhibitor/Angiotensin II receptor antagonist (ACEI/ARB) usage (P = 0.039), IABP usage (P = 0.040) and CI-AKI occurring after administration of the first agent (P = 0.015) were independent predictors of CI-AKI after the second. Furthermore, dividing the patients into tertiles of the time interval between the two agents showed that CI-AKI occurred more frequently when the second agent was administered within 1-3 days after the first exposure than within 4-6 days (12.4% vs. 5.0%, P = 0.008) or ≥ 7 days (12.4% vs. 6.4%, P = 0.039).

CONCLUSIONS

Diuretic and IABP usage are independent predictors of CI-AKI following exposure to a first contrast agent. The major predictors of CI-AKI after exposure to a second agent are time since the first contrast exposure, ACEI/ARB usage, and IABP usage. More importantly, a three-day interval between the two agents is associated with a higher incidence of CI-AKI following the second administration.

Efficacy of Oral Nicorandil to Prevent Contrast-Induced Nephropathy in Patients with Chronic Renal Dysfunction Undergoing an Elective Coronary Procedure

Objectives: This prospective, randomized study was to investigate the role of nicorandil in the prevention of contrast-induced nephropathy (CIN) in patients with chronic renal dysfunction undergoing an elective coronary procedure. Methods: A total of 252 eligible patients were enrolled in this study and allocated into the control group (n = 125) or nicorandil group (n = 127). Both groups received the standard hydration treatment, and patients in the nicorandil group were orally administrated 10 mg of nicorandil (t.i.d.) beginning 2 days before and continuing for 2 days after an elective coronary procedure. Serum creatinine (SCr) and cystatin C (CysC) were measured at 24 h before and 24, 48, and 72 h after the procedure. The occurrences of CIN and adverse events within 1 year were recorded. Results: The nicorandil group had relatively lower SCr and CysC levels and a higher eGFR at 24 and 48 h after the procedure than the control group (p < 0.05). The incidence of CIN was significantly decreased in the nicorandil group compared to the control group. The multivariate logistic regression model revealed that nicorandil treatment was an independent protective factor for CIN (OR 0.669, 95% CI 0.522–0.857, p = 0.001). The multivariate COX proportional hazard model showed that nicorandil treatment was an independent protective predictor for adverse events (HR 0.881, 95% CI 0.781–0.993, p = 0.037). Conclusions: Nicorandil could exhibit a protective effect against CIN in patients with chronic renal dysfunction undergoing an elective coronary procedure and reduce the adverse events within 1 year after the procedure, which is superior to hydration treatment only.

Association between Contrast Media Volume and 1-Year Clinical Outcomes in Patients Undergoing Coronary Angiography

Background:

The excess volume of contrast media (CM) is a marker of a more severe coronary culprit lesion and longer intervention duration in patients undergoing cardiac procedures. However, it is unclear whether the contrast volume is directly correlated with worse clinical outcomes. The aim of this study was to investigate the association between contrast dose and the incidence of 1-year major adverse cardiac and cerebrovascular events (MACCE) and all-cause bleeding events in patients undergoing cardiac catheterization and coronary angiography (CAG).

Methods:

We prospectively enrolled 10,961 consecutive patients diagnosed with coronary heart disease expecting CAG from 2012 to 2013. The study population was pursued with a follow-up duration of 1 year. The predictive value of contrast volume, divided into quartiles, for the risk of MACCE and all-cause bleeding events was assessed using logistic regression analysis.

Results:

The cumulative incidence of 1-year MACCE was 8.65%, which was directly associated with increasing contrast volume. In particular, MACCE was observed in 7.16%, 7.89%, 9.31%, and 11.73% of cases in the contrast volume quartile Q1 (≤100 ml), Q2 (101–140 ml), Q3 (141–200 ml), and Q4 (>200 ml), respectively (P < 0.001). Moreover, the incidence of 1-year all-cause bleeding events was noted in 4.70%, 5.93%, 7.28%, and 8.21% of patients in Q1, Q2, Q3, and Q4, respectively (P < 0.001). The survival analysis showed that the 1-year MACCE rate was higher in patients using greater CM volume during the CAG. CM volume used >140 ml was associated with the occurrence of 1-year MACCE, and the incidence was dramatically elevated in patients exceeding a contrast volume of 200 ml (P = 0.007).

Conclusion:

Our data suggested that higher contrast volume was significantly correlated with an increased risk of MACCE and all-cause bleeding events in patients undergoing cardiac catheterization.

Trial Registration:

ClinicalTrials.gov, NCT01735305; https://clinicaltrials.gov/ct2/show/NCT01735305?id=NCT017353057rank=1.

Contrast-Induced Nephropathy and Long-Term Clinical Outcomes Following Percutaneous Coronary Intervention in Patients With Advanced Renal Dysfunction (Estimated Glomerular Filtration Rate <30 ml/min/1.73 m2)

The incidence of contrast-induced nephropathy (CIN) increases with the progression of renal dysfunction. Recent reports have shown that percutaneous coronary intervention (PCI) can be safely performed even in patients with advanced renal dysfunction by appropriate CIN-prevention strategies. However, data are limited regarding the occurrence and prognostic influence of CIN in patients with advanced renal dysfunction. We examined the data obtained from 323 consecutive patients with advanced renal dysfunction (eGFR <30 ml/min/1.73 m²) who underwent PCI at 5 hospitals. CIN was defined as a ≥25% increase in baseline serum creatinine levels and/or a ≥0.5 mg/dl increase in absolute serum creatinine levels within 72 hours after PCI. Incidence of all-cause death and the initiation of permanent dialysis were examined during follow-up. The prevalence of emergency/urgent PCI was 53.3%. Intravascular ultrasound was used in 266 patients (82.4%), and the volume of contrast used was 71.7 ± 57.2 ml. CIN was observed in 31 patients (9.7%). The median follow-up duration was 656 days (interquartile range 257-1143 days). The cumulative rates of all-cause death or the initiation of permanent dialysis, all-cause death, and the initiation of permanent dialysis were 38.1%, 25.9%, and 18.2%, respectively, at 2 years. A comparison between patients with and without CIN showed no significant intergroup differences in the occurrence of the aforementioned events. In conclusion, the incidence of CIN was not high in Japanese patients with advanced renal dysfunction in routine clinical practice. Whereas, the long-term prognosis following PCI is observed to be poor in this studied population, and CIN did not show a significant prognostic influence.

Evaluation of neutrophil gelatinase-associated lipocalin and cystatin C as biomarkers of acute kidney injury after ST-segment elevation myocardial infarction treated by percutaneous coronary intervention

BACKGROUND

Two biomarkers of early acute kidney injury-plasmatic neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C-are not used in routine clinical practice in patients with ST-segment elevation myocardial infarction (STEMI) treated by percutaneous coronary intervention (PCI) because of a lack of supporting data.

AIMS

To evaluate the predictive value of NGAL and cystatin C regarding the incidence of contrast-induced acute kidney injury (CI-AKI) and clinical outcomes after STEMI in patients treated by primary PCI.

METHODS

Plasmatic NGAL and cystatin C were measured on admission, before any contrast exposure, in 701 unselected patients with STEMI. Associations between biomarker concentrations and incidence of CI-AKI (assessed at 48h), haemodialysis requirement at 1 year and all-cause mortality at 1 year were assessed by logistic regression analyses and receiver operating characteristic area under the curve analysis (c-statistic). Discrimination performance comparison was performed using the DeLong test.

RESULTS

NGAL and cystatin C had mild discrimination regarding CI-AKI, with c-statistics of 0.60 (P=0.001) and 0.60 (P=0.002), respectively. Combining NGAL and cystatin C did not improve their discrimination (c-statistic 0.61; P=0.001). There was no significant difference in discrimination between NGAL, cystatin C and baseline creatinine (P=0.57). Regression analyses showed no independent association between NGAL and CI-AKI, haemodialysis or 1-year mortality. Similarly, cystatin C was not associated with these clinical outcomes.

CONCLUSIONS

In this cohort of patients with STEMI treated by primary PCI, plasmatic NGAL and cystatin C did not provide additional value regarding CI-AKI prediction compared with known risk factors such as baseline creatinine.

Anemia (Hemoglobin ≤ 13 g/dL) as a Risk Factor for Contrast-Induced Acute Kidney Injury Following Coronary Angiography

Contrast-induced acute kidney injury (CI-AKI) following coronary angiography is associated with increased mortality. The association between severity of anemia and CI-AKI following coronary angiography is not well-established. In this retrospective study, we aimed at assessing the association of anemia of various severity with the risk of CI-AKI in patients who underwent coronary angiography. We included all patients who underwent coronary angiography with or without percutaneous coronary intervention from January 2012 to December 2016 at a single tertiary care hospital. CI-AKI was defined as ≥0.3 mg/dL increase in creatinine from baseline and anemia was defined as baseline hemoglobin ≤13 g/dL. Patients were stratified into three subgroups-mild (11.1 to 13.0 g/dL), moderate (9.1 to 11.0 g/dL) and severe anemia (7.0 to 9.0 g/dL). Crude and adjusted odds ratios (AOR) were calculated using univariate multiple logistic regression analysis. Of 2,055 patients (females = 30.7%, mean age 58.0 ± 12.5 years) who underwent coronary angiography, 293 (14.3%) developed CI-AKI. Presence of anemia was associated with increased risk of developing CI-AKI (AOR = 5.3, 95% confidence interval [CI] = 3.8 to 7.3, p < 0.001). Risk of CI-AKI was increasingly higher with increasing severity of the anemia; mild (AOR = 3.4, 95% CI = 2.5 to 4.7, p < 0.001), moderate (AOR = 9.8, 95% CI = 6.9 to 14.2, p < 0.001) and severe (AOR = 13.7, 95% CI = 8.2 to 23.1, p < 0.001). In conclusion, severity of anemia is a strong predictor of CI-AKI following coronary angiography.

Relationship between High Level of Estimated Glomerular Filtration Rate and Contrast-Induced Acute Kidney Injury in Patients who Underwent an Emergency Percutaneous Coronary Intervention

Background

Mounts of studies have shown that low estimated glomerular filtration rate (eGFR) is associated with increased risk of adverse outcomes in patients with coronary artery disease. However, high level of eGFR was less reported. In the study, we aimed to explore the relationship between the baseline eGFR, especially the high level, and contrast-induced acute kidney injury (CI-AKI) in a Chinese population who underwent an emergency percutaneous coronary intervention (PCI).

Methods

Patients who underwent an emergency PCI from 2013 to 2015 were enrolled and divided into five groups as eGFR decreasing. Baseline characteristics were collected and analyzed. The rates of CI-AKI and the composite endpoint (including nonfatal myocardial infarction, revascularization, stroke, and all-cause death) at 6- and 12-month follow-up were compared. Logistic analysis for CI-AKI was performed.

Results

A total of 1061 patients were included and the overall CI-AKI rate was 22.7% (241/1061). The separate rates were 77.8% (7/9) in Group 1 (eGFR ≥120 ml·min^-1·1.73 m^-2), 26.0% (118/454) in Group 2 (120 ml·min^-1·1.73 m^-2> eGFR ≥90 ml·min^-1·1.73m^-2), 18.3% (86/469) in Group 3 (90 ml·min^-1·1.73 m^-2> eGFR ≥60 ml·min^-1·1.73 m^-2), 21.8% (26/119) in Group 4 (60 ml·min^-1·1.73 m^-2> eGFR ≥30 ml·min^-1·1.73 m^-2), and 40.0% (4/10) in Group 5 (eGFR <30 ml·min^-1·1.73 m^-2), with statistical significance (χ² = 25.19, P < 0.001). The rates of CI-AKI in five groups were 77.8%, 26.0%, 18.3%, 21.8%, and 40.0%, respectively, showing a U-typed curve as eGFR decreasing (the higher the level of eGFR, the higher the CI-AKI occurrence in case of eGFR ≥60 ml·min^-1·1.73 m^-2). The composite endpoint rates in five groups were 0, 0.9%, 2.1%, 6.7%, and 0 at 6-month follow-up, respectively, and 0, 3.3%, 3.4%, 16.0%, and 30.0% at 12-month follow-up, respectively, both with significant differences (χ² = 16.26, P = 0.009 at 6-month follow-up, and χ² = 49.05, P < 0.001 at 12-month follow-up). The logistic analysis confirmed that eGFR was one of independent risk factors of CI-AKI in emergency PCI patients.

Conclusions

High level of eGFR might be associated with increased risk of CI-AKI in patients with emergency PCI, implying for future studies and risk stratification in clinical practice.

Contrast-Induced Acute Kidney Injury after Coil Embolization for Aneurysmal Subarachnoid Hemorrhage

PURPOSE

Contrast-induced acute kidney injury (CI-AKI) is associated with poor outcomes after percutaneous coronary intervention. However, CI-AKI has rarely been evaluated within the neurovascular field. The aim of this study was to investigate the incidence and clinical implication of CI-AKI after coil embolization in patients with an aneurysmal subarachnoid hemorrhage (aSAH).

MATERIALS AND METHODS

Between January 2005 and March 2016, 192 patients who underwent coil embolization were enrolled in this study. CI-AKI was defined as an increase from baseline serum creatinine concentration of >25% or >0.5 mg/dL within 72 hours after coil embolization. A poor clinical outcome was defined as a score of ≥3 on the modified Rankin Scale at one-year post-treatment.

RESULTS

A total of 16 patients (8.3%) died as a result of medical problems within one year. CI-AKI was identified in 14 patients (7.3%). Prominent risk factors for one-year mortality included CI-AKI [odds ratio (OR): 16.856; 95% confidence interval (CI): 3.437-82.664] and an initial Glasgow Coma Scale (GCS) score ≤8 (OR: 5.565; 95% CI: 1.703-18.184). A poor clinical outcome was associated with old age (≥65 years) (OR: 7.921; 95% CI: 2.977-21.076), CI-AKI (OR: 11.281; 95% CI: 2.138-59.525), an initial GCS score ≤8 (OR 31.02; 95% CI, 10.669-90.187), and a ruptured aneurysm (p=0.016, OR: 4.278) in posterior circulation.

CONCLUSION

CI-AKI seems to be an independent predictor of the overall outcomes of aSAH after endovascular treatment.

Does contrast media volume affect long-term survival in patients with chronic kidney disease?

Introduction

The aim of this study was to investigate the relationships between survival and related features in patients with chronic kidney disease undergoing cardiac catheterization and coronary angiography.

Material and methods

Three hundred and seven consecutive patients with an estimated glomerular filtration rate (e-GFR) less than 60 ml/min/1.73 m² undergoing coronary angiography were enrolled in the study. The study population was pursued with a median follow-up duration of 41.5 months.

Results

In the Cox proportional hazards regression model, age (HR = 1.047, 95% CI: 1.011-1.084, p = 0.01), contrast media volume (HR = 1.004, 95% CI: 1.001-1.007, p = 0.008), angiotensin II receptor blocker (ARB) use (HR = 0.485, 95% CI: 0.261-0.901, p = 0.02), and e-GFR (HR = 0.978, 95% CI: 0.940-1.016, p = 0.04) were found to be independent predictors of long-term all-cause mortality. The survival analysis showed that the long-term all-cause mortality rate was higher in patients using contrast media volume greater than 140 ml compared to patients given less than or equal to 140 ml during the coronary angiography (3.6% vs. 11.6% log-rank, p = 0.001).

Conclusions

In patients with chronic kidney disease undergoing cardiac catheterization, age, contrast media volume, e-GFR and low ARB use were found to be independent predictors of long-term all-cause mortality. Contrast media volume used > 140 ml was independently associated with long-term all-cause mortality compared to less than or equal to 140 ml during cardiac catheterization.

Image quality and radiation dose of low-tube-voltage CT with reduced contrast media for right adrenal vein imaging

OBJECTIVES

To compare image quality and radiation dose of right adrenal vein (RAV) imaging computed tomography (CT) among conventional, low kV, and low kV with reduced contrast medium protocols.

METHODS

One-hundred-and-twenty patients undergoing adrenal CT were randomly assigned to one of three protocols: contrast dose of 600mgI/kg at 120-kV tube voltage setting (600-120 group), 600mgI/kg at 80kV (600-80 group), and 360mgI/kg at 80kV (360-80 group). Iterative reconstruction was used for 80-kV groups. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the RAV and size-specific dose estimates (SSDE) were measured. Three radiologists evaluated 4-point visualisation scores of RAV by consensus reading.

RESULTS

The RAV detectability was 95%, 97.2%, and 97.3% for 600-120, 600-80, and 360-80 groups, respectively (p=1.000). Visualisation scores were not significantly different among the groups (p=0.152). There were no significant differences in CNR or SNR between the 600-120 and 360-80 groups. SSDE of the 360-80 group was significantly lower than that of the 600-120 group (5.86mGy±1.44 vs. 7.27mGy±1.81, p<0.001).

CONCLUSIONS

80-kV scans with 360 mgI/kg contrast media showed comparable detectability of RAV to conventional scans, while reducing 19% of SSDE.

A New Risk Factor Profile for Contrast-Induced Acute Kidney Injury in Patients Who Underwent an Emergency Percutaneous Coronary Intervention

We developed a new risk factor profile for contrast-induced acute kidney injury (CI-AKI) under a new definition in patients who underwent an emergency percutaneous coronary intervention (PCI). Consecutive patients (n = 1061) who underwent an emergency PCI were divided into a derivation group (n = 761) and a validation group (n = 300). The rates of CI-AKI were 23.5% (definition 1: serum creatinine [SCr] increase ≥25% in 72 hours), 4.3% (definition 2: SCr increase ≥44.2 μmol/L in 72 hours), and 7.0% (definition 3: SCr increase ≥44.2 μmol/L in 7 days). Due to the high sensitivity of definition 1 and the high rate of missed cases for late diagnosis of CI-AKI under definition 2, definition 3 was used in the study. The risk factor profile included body surface area <1.6 m2 ( P = .030), transient ischemic attack/stroke history ( P = .001), white blood cell count >15.00 × 109/L ( P = .047), estimated glomerular filtration rate <60 mL/min/1.73 m2 ( P = .002) or baseline SCr >133 μmol/L ( P = .007), intra-aortic balloon pump application ( P = .006), and diuretics administration ( P < .001), showing a significant predictive power in the derivation group and validation group. The new risk factor profile of CI-AKI under a new CI-AKI definition in emergency PCI patients is easily applicable with a useful predictive value.

ESRD After Heart Failure, Myocardial Infarction, or Stroke in Type 2 Diabetic Patients With CKD

BACKGROUND

How cardiovascular (CV) events affect progression to end-stage renal disease (ESRD), particularly in the setting of type 2 diabetes, remains uncertain.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

4,022 patients with type 2 diabetes, anemia, and chronic kidney disease from the Trial to Reduce Cardiovascular Events With Aranesp Therapy (TREAT).

PREDICTOR

Postrandomization CV events.

OUTCOMES

ESRD (defined as initiation of dialysis for >30 days, kidney transplantation, or refusal or nonavailability of renal replacement therapy) and post-ESRD mortality within 30 days and during overall follow-up after an intercurrent CV event.

LIMITATIONS

Population limited to clinical trial participants with diabetes and anemia.

RESULTS

155 of 652 (23.8%) ESRD cases occurred after an intercurrent CV event; 110 (16.9%) cases followed heart failure, 28 (4.3%) followed myocardial infarction, 12 (1.84%) followed stroke, and 5 (0.77%) followed multiple CV events. ESRD rate was higher within 30 days in individuals with an intercurrent CV event compared with those without an intercurrent event (HR, 22.2; 95% CI, 17.0-29.0). Compared to no intercurrent CV events, relative risks for ESRD were higher after the occurrence of heart failure overall (HR, 3.4; 95% CI, 2.7-4.2) and at 30 days (HR, 20.1; 95% CI, 14.5-27.9) than after myocardial infarction or stroke (P<0.001). Compared with individuals without pre-ESRD events, those with ESRD following intercurrent CV events were older, were more likely to have prior CV disease, and had higher (24.4 vs 23.1mL/min/1.73m²; P=0.01) baseline estimated glomerular filtration rates (eGFRs) and higher eGFRs at last measurement before ESRD (18.6 vs 15.2mL/min/1.73m²; P<0.001), whereas race, sex, and medication use were similar. Post-ESRD mortality was similar (P=0.3) with and without preceding CV events.

CONCLUSIONS

Most ESRD cases occurred in individuals without intercurrent CV events who had lower eGFRs than individuals with intercurrent CV events, but similar post-ESRD mortality. Nevertheless, intercurrent CV events, particularly heart failure, are strongly associated with risk for ESRD. These findings underscore the need for kidney-specific therapies in addition to treatment of CV risk factors to lower ESRD incidence in diabetes.

Contrast-induced acute kidney injury: A review of practical points

Contrast-induced acute kidney injury (CI-AKI) is one of the most common causes of AKI in clinical practice. CI-AKI has been found to be strongly associated with morbidity and mortality of the patients. Furthermore, CI-AKI may not be always reversible and it may be associated with the development of chronic kidney disease. Pathophysiology of CI-AKI is not exactly understood and there is no consensus on the preventive strategies. CI-AKI is an active research area thus clinicians should be updated periodically about this topic. In this review, we aimed to discuss the indications of contrast-enhanced imaging, types of contrast media and their impact on nephrotoxicity, major pathophysiological mechanisms, risk factors and preventive strategies of CI-AKI and alternative non-contrast-enhanced imaging methods.

Contrast-Induced Acute Kidney Injury: An Update

Contrast-induced acute kidney injury (CI-AKI) is defined as an abrupt deterioration in renal function associated with the administration of iodinated contrast media. This type of acute kidney injury is frequently encountered as a complication of percutaneous coronary intervention (PCI) and is associated with adverse short- and long-term outcomes including mainly mortality, cardiovascular morbidity and prolongation of hospitalization. The incidence of CI-AKI after PCI ranges from 2 to 20 % according to baseline kidney function. It may also range according to the clinical setting, being higher after emergency PCI. The primary manifestation is a small decline in kidney function, occurring 1 to 3 days after the procedure. Kidney function usually returns to preexisting levels within 7 days. Incidence of acute renal failure requiring dialysis following PCI is rare (<1 %). The present article aims to review up-to-date published data concerning diagnosis, definition, epidemiology and prognosis of this novel in-hospital epidemic.

Acute kidney injury in cirrhotic patients undergoing contrast-enhanced computed tomography

Contrast medium administration is one of the leading causes of acute kidney injury (AKI) in different clinical settings. The aim of the study was to investigate occurrence and predisposing factors of AKI in cirrhotic patients undergoing contrast-enhanced computed tomography (CECT).Datasets of 1279 consecutively hospitalized cirrhotic patients were retrospectively analyzed. Two hundred forty-nine of 1279 patients (mean age 64 ± 11 years, 165 male) who had undergone CECT were selected on the basis of the availability of serum creatinine (sCr) values evaluated before and after CECT (CECT group). In analogy, 203/1279 cases (mean age 66 ± 10 years, 132 male) who had not undergone CECT and had been tested twice for sCr in 7 days were also included as controls (Control group). AKI network criteria were employed to assess contrast-induced AKI (CI-AKI) development. Apart from lack of narrowed double sCr measurements, additional exclusion criteria were active bacterial infections, nephrotoxic drugs intake, and estimated glomerular filtration rate <30 mL/min.AKI developed in 22/249 (8.8%) and in 6/203 (3%) of the CECT and the Control groups, respectively (P = 0.01). The multivariate logistic regression analysis showed that AKI was significantly associated with contrast medium administration (odds ratio [OR]: 3.242, 95% confidence interval [CI]: 1.255-8.375; P = 0.015), female sex (OR: 0.339, 95% CI: 0.139-0.827; P = 0.017), and sCr values (OR: 0.124, 95% CI: 0.016-0.975; P = 0.047). In the CECT group, presence of ascites (OR: 2.796, 95% CI: 1.109-7.052; P = 0.029), female sex (OR: 0.192, 95% CI: 0.073-0.510; P = 0.001), and hyperazotemia (OR: 1.018, 95% CI: 1.001-1.037; P = 0.043) correlated with CI-AKI development at multivariate analysis.CI-AKI is a quite frequent occurrence in cirrhotic patients with female sex, presence of ascites, and hyperazotemia being the predisposing factors.

Acute kidney damage induced by low- and iso-osmolar contrast media in rats: Comparison study with physiologic MRI and histologic-gene examination

PURPOSE

To investigate the physiopathological effects of low- and iso-osmolar contrast media (CM) on renal function with physiologic MRI and histologic-gene examination.

MATERIALS AND METHODS

Forty-eight rats underwent time-course DWI and DCE-MRI at 3.0 Tesla (T) before and 5-15 min after exposure of CM or saline (Iop.370: 370 mgI/mL iopromide; Iod.320: 320 mgI/mL iodixanol; Iod.270: 270 mgI/mL iodixanol; 4 gI/kg body weight). Intrarenal viscosity was reflected by apparent diffusion coefficient (ADC). Renal physiologies were evaluated by DCE-derived glomerular filtration rate (GFR), renal blood flow (RBF), and renal blood volume (RBV). Potential acute kidney injury (AKI) was determined by histology and the expression of kidney injury molecule 1 (Kim-1).

RESULTS

Iop.370 mainly increased ADC in inner-medulla (△ADC_IM : 12.3 ± 11.1%; P < 0.001). Iod.320 and Iod.270 mainly decreased ADC in outer-medulla (△ADC_IM ; Iod.320: 16.8 ± 7.5%; Iod.270: 18.1 ± 9.5%; P < 0.001) and inner-medulla (△ADC_IM ; Iod.320: 28.4 ± 9.3%; Iod.270: 30.3 ± 6.3%; P < 0.001). GFR, RBF and RBV were significantly decreased by Iod.320 (△GFR: 45.5 ± 24.1%; △RBF: 44.6 ± 19.0%; △RBV: 35.2 ± 10.1%; P < 0.001) and Iod.270 (33.2 ± 19.0%; 38.1 ± 15.6%; 30.1 ± 10.1%; P < 0.001), while rarely changed by Iop.370 and saline. Formation of vacuoles and increase in Kim-1 expression was prominently detected in group of Iod.320, while rarely in Iod.270 and Iop.370.

CONCLUSION

Iso-osmolar iodixanol, given at high-dose, produced prominent AKI in nonhydrated rats. This renal dysfunction could be assessed noninvasively by physiologic MRI.

LEVEL OF EVIDENCE

1 J. Magn. Reson. Imaging 2017;45:291-302.

AKI and Long-Term Risk for Cardiovascular Events and Mortality

AKI associates with increased long-term risk of mortality, but the prognostic significance of AKI in terms of long-term cardiovascular disease remains unconfirmed. We conducted a systematic review and meta-analysis to assess whether AKI associates with long-term cardiovascular disease. We included cohort studies that examined adults with and without AKI and reported a multivariable-adjusted relative risk (RR) for the association between AKI and cardiovascular mortality, major cardiovascular events, and disease-specific events: congestive heart failure, acute myocardial infarction, and stroke. Twenty-five studies involving 254,408 adults (55,150 with AKI) were included. AKI associated with an 86% and a 38% increased risk of cardiovascular mortality and major cardiovascular events, respectively ([RR 1.86; 95% confidence interval (95% CI), 1.72 to 2.01] and [RR 1.38; 95% CI, 1.23 to 1.55], respectively). For disease-specific events, AKI associated with a 58% increased risk of heart failure (RR 1.58; 95% CI, 1.46 to 1.72) and a 40% increased risk of acute myocardial infarction (RR 1.40; 95% CI, 1.23 to 1.59). The elevated risk of heart failure and acute myocardial infarction persisted in subgroup analyses on the basis of AKI severity and the proportion of adults with baseline ischemic heart disease. Finally, AKI was associated with a 15% increased risk of stroke (RR 1.15; 95% CI, 1.03 to 1.28). In conclusion, AKI associates with an elevated risk of cardiovascular mortality and major cardiovascular events, particularly heart failure and acute myocardial infarction.

Comparison of Intravenous and Oral Hydration in the Prevention of Contrast-Induced Acute Kidney Injury in Low-Risk Patients: A Randomized Trial

AIMS

Contrast-induced acute kidney injury (CI-AKI) is a common cause of renal failure. We evaluated the effectiveness of oral sodium citrate versus intravenous (IV) sodium bicarbonate for CI-AKI prophylaxis as well as their influence on kidney injury biomarkers.

MATERIAL AND METHODS

A randomized, controlled, single-center study including 130 hospitalized patients (62.3% men), who were randomized to receive sodium bicarbonate (1/6 men, 3 ml/kg/h for 1 h; n = 43), oral sodium citrate (75 ml/10 kg divided into 4 doses; n = 43) or nonspecific hydration (n = 44) before contrast administration, was conducted. Serum creatinine and kidney injury biomarkers (cystatin C, neutrophil gelatinase-associated lipocalin, interleukin-8, F2-isoprostanes and cardiotrophin-1 [CT-1]) were assessed.

RESULTS

Incidence of CI-AKI was 9.2% with no differences found between hydration groups: 7.0% in sodium bicarbonate group, 11.6% in oral sodium citrate group and 9.1% in the nonspecific hydration group. Urinary creatinine and urinary CT-1/creatinine ratio decreased 4 h after contrast infusion (p < 0.001), but none of the biomarkers assessed were affected by the treatments.

CONCLUSIONS

There were no differences in hydration with oral sodium citrate and IV sodium bicarbonate for the prophylaxis of CI-AKI. Therefore, oral hydration represents a safe, inexpensive and practical method for preventing CI-AKI in low-risk patients. No effect on biomarkers for kidney injury could be demonstrated.

Preconditioning With Tauroursodeoxycholic Acid Protects Against Contrast-Induced HK-2 Cell Apoptosis by Inhibiting Endoplasmic Reticulum Stress

To investigate whether tauroursodeoxycholic acid (TUDCA) could attenuate contrast media (CM)-induced renal tubular cell apoptosis by inhibiting endoplasmic reticulum stress (ERS), we exposed HK-2 cells to increasing doses of meglumine diatrizoate (20, 40, and 80 mg I/mL) for 2 to 16 hours, with/without TUDCA preconditioning for 24 hours. Cell viability test, Hoechst 33258 staining, and flow cytometry were used to detect meglumine diatrizoate-induced cell apoptosis, while real-time polymerase chain reaction and Western blot analysis were used to measure the expressions of ERS markers of glucose-regulated protein 78 (GRP78), activating transcription factor 4 (ATF4), and the apoptosis-related marker of caspase 12. Cell apoptosis and messenger RNA (mRNA) expression of GRP78 ( P = .005), ATF4 ( P = .01), and caspase 12 ( P = .001) were significantly higher in the CM 4 hours group than the control as well as the protein expressions. The TUDCA preconditioning reduced the mRNA expression of GRP78, ATF4, and caspase 12 in the CM 4 hours groups ( P = .009, .019, and .003, respectively) as well as the protein expression. In conclusion, TUDCA could protect renal tubular cells from meglumine diatrizoate-induced apoptosis by inhibiting ERS.