A Meta-Analysis of the Renal Safety of Isosmolar Iodixanol Compared With Low-Osmolar Contrast Media

Microvascular changes following exposure to iodinated contrast media in vitro. A qualitative comparison to serum creatinine concentrations in post-cardiac catheterization patients

INTRODUCTION

Contrast-associated acute kidney injury (CA-AKI) is characterized as a loss of renal function following radiological contrast media administration. While all contrast media induce variable changes in microvascular endothelial cells in vitro, only few studies report clinical significance of their findings. A comprehensive assessment of the effect of iodinated contrast media on the renal function in vitro and in vivo is essential. The aim of our study was to morphometrically quantify the effect of two different contrast media (Iobitridol and Iodixanol) on vascular endothelial capillaries in vitro and to analyze their effect on the renal function of patients who underwent cardiac catheterization including the intra-arterial administration of contrast media, by measuring serum creatinine concentration (SCr), a byproduct of muscle metabolism, primarily excreted by the kidneys. Our hypothesis suggests that conducting a qualitative comparison of both outcomes will enable identification of differences and similarities between in vitro and in vivo exposure.

MATERIAL AND METHODS

In vitro, co-cultures of human dermal fibroblasts and human dermal microvascular endothelial cells forming capillary beds were exposed to a mixture of phosphate buffered saline and either Iobitridol, Iodixanol, or one of their supplements EDTA or Trometamol for 1.5 or 5 min. Negative control co-cultures were exposed exclusively to phosphate buffered saline. Co-cultures were either directly fixed or underwent a regeneration time of 1, 3 or 7 days. An artificial intelligence software was trained for detection of labeled endothelial capillaries (CD31) on light microscope images and measurements of morphometric parameters. In vivo, we retrospectively analyzed data from patients who underwent intra-arterial administration of contrast media and for whom SCr values were available pre- and post-contrast exposition (1, 3, and 7 days following procedure). Temporal development of SCr and incidence of CA-AKI were assessed. Both exposure types were qualitatively compared.

RESULTS

In vitro, Iobitridol, Iodixanol and EDTA induced a strong decrease of two morphometric parameters after 3 days of regeneration. In vivo, a significant increase of SCr and incidence of CA-AKI was observed 3 days following procedure in the post-contrast media patients. No difference was observed between groups.

DISCUSSION

Two of the morphometric parameters were inversely proportional to the SCr of the patients. If the endothelial damages observed in vitro occur in vivo, it may result in renal hypoxia, inducing a loss of kidney function clinically translated into an increase of SCr. Further development of our in vitro model could allow closer replication of the internal structure of a kidney and bridge the gap between in vitro studies and their clinical findings.

Repurposing naproxen as a potential nucleocapsid antagonist of beta-coronaviruses: targeting a conserved protein in the search for a broad-spectrum treatment option

Ongoing mutations in the coronavirus family, especially beta-coronaviruses, raise new concerns about the possibility of new unexpected outbreaks. Therefore, it is crucial to explore new alternative treatments to reduce the impact of potential future strains until new vaccines can be developed. A promising approach to combat the virus is to target its conserved parts such as the nucleocapsid, especially via repurposing of existing drugs. The possibility of this approach is explored here to find a potential anti-nucleocapsid compound to target these viruses. 3D models of the N- and C-terminal domains (CTDs) of the nucleocapsid consensus sequence were constructed. Each domain was then screened against an FDA-approved drug database, and the most promising candidate was selected for further analysis. A 100 ns molecular dynamics (MD) simulation was conducted to analyze the final candidate in more detail. Naproxen was selected and found to interact with the N-terminal domain via conserved salt bridges and hydrogen bonds which are completely conserved among all Coronaviridae members. MD analysis also revealed that all relevant coordinates of naproxen with N terminal domain were kept during 100 ns of simulation time. This study also provides insights into the specific interaction of naproxen with conserved RNA binding pocket of the nucleocapsid that could interfere with the packaging of the viral genome into capsid and virus assembly. Additionally, the in-vitro binding assay demonstrated direct interaction between naproxen and recombinant nucleocapsid protein, further supporting the computational predictions.Communicated by Ramaswamy H. Sarma.

Thyroid dysfunction associated with iodine-contrast media: A real-world pharmacovigilance study based on the FDA adverse event reporting system

Objective

To comprehensively analyze characteristics of thyroid dysfunction associated with iodine contrast media (ICM) based on data from the FDA adverse event reporting system (FAERS).

Methods

Disproportionate analysis was employed to identify signals of thyroid dysfunction caused by ICM, and descriptive analysis was performed to examine the clinical characteristics of reported cases involving ICM-related thyroid dysfunctions.

Results

A total of 83 adverse event reports were identified, documenting thyroid dysfunctions associated with ICM agents. Treatment with ICM was significantly associated with higher reporting of hypothyroidism ([ROR] = 2.21, 95 % CI: 1.59-3.08; IC025 = 0.58) and hyperthyroidism (ROR = 3.49, 95 % CI: 2.37-5.13; IC025 = 1.14). Among the six ICM agents investigated, iodixanol demonstrated the highest signal strength in both hypothyroidism (ROR = 9.47) and hyperthyroidism (ROR = 5.44). Hypothyroidism and hyperthyroidism almost occurred in the first 30 days after ICM administration (76.9 % and 70 % of patients, respectively). Furthermore, the proportion of severe outcomes in hyperthyroidism was significantly higher than that in hypothyroidism (12/26 vs. 2/35, P = 0.009).

Conclusion

The present study highlights the varying risks of thyroid dysfunction associated with different ICM agents, with iodixanol exhibiting the highest signal intensity. Hypothyroidism and hyperthyroidism associated with ICM generally manifest within the first month following administration. Consequently, monitoring of thyroid function during this period is strongly recommended for ICM agents presenting higher risk profiles.

Efficacy and Safety of Iodixanol in Computed Coronary Tomographic Angiography and Cardiac Catheterization

Iodixanol is an iso-osmolar non-ionic dimeric hydrophilic contrast agent with a higher viscosity than the monomeric agents. It is the only Food and Drug Administration (FDA)-approved iso-osmolar agent in the United States, and it is the only contrast agent with an FDA-approved indication for use in cardiac computed tomographic angiography (CCTA), to assist in the diagnostic evaluation of patients with suspected coronary artery disease. In clinical studies, it has been noted to have fewer side effects and similar image quality when compared to low-osmolar contrast media. This can be attributed to the pharmacological properties of iodixanol. These contrast agents are used for coronary computed tomography angiography and cardiac catheterization. In this article, the use, tolerability, and efficacy of iodixanol are reviewed, specifically evaluating the use of CCTA and coronary angiography, including outcome studies, randomized trials, and comparisons to other contrast agents.

Acute Kidney Injury Management Strategies Peri-Cardiovascular Interventions

In many countries, the aging population and the higher incidence of comorbid conditions have resulted in an ever-growing need for cardiac interventions. Acute kidney injury (AKI) is a common complication of these interventions, associated with higher mortalities, chronic or end-stage kidney disease, readmission rates, and hospital and post-discharge costs. The AKI pathophysiology includes contrast-associated AKI, hemodynamic changes, cardiorenal syndrome, and atheroembolism. Preventive measures include limiting contrast media dose, optimizing hemodynamic conditions, and limiting exposure to other nephrotoxins. This review article outlines the current state-of-art knowledge regarding AKI pathophysiology, risk factors, preventive measures, and management strategies in the peri-interventional period.

Contrast removal from coronary sinus for prevention of contrast-induced nephropathy: a review

The occurrence of contrast-induced-nephropathy (CIN) is related to the amount of contrast administration. Any removal of contrast from systemic circulation before reaching the kidneys might be beneficial using a device that removes contrast from a coronary sinus (CS). This manuscript aims to review the available literature regarding contrast removal from CS during coronary angiography or intervention for the prevention of CIN.

Management of Patients With Kidney Disease in Need of Cardiovascular Catheterization: A Scientific Workshop Cosponsored by the National Kidney Foundation and the Society for Cardiovascular Angiography and Interventions

Patients with chronic kidney disease (CKD) are at an increased risk of developing cardiovascular disease (CVD), whereas those with established CVD are at risk of incident or progressive CKD. Compared with individuals with normal or near normal kidney function, there are fewer data to guide the management of patients with CVD and CKD. As a joint effort between the National Kidney Foundation and the Society for Cardiovascular Angiography and Interventions, a workshop and subsequent review of the published literature was held. The present document summarizes the best practice recommendations of the working group and highlights areas for further investigation.

Evaluation of contrast-induced acute kidney injury using IVIM and DKI MRI in a rat model of diabetic nephropathy

Objective

To assess the potential of intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) in monitoring renal changes in a diabetic nephropathy (DN) rat model with acute kidney injury (CI-AKI) induced by iso-osmotic contrast media (IOCM) and low-osmotic contrast media (LOCM).

Methods

A diabetic nephropathy rat model was established, and the animals were randomly split into the LOCM group and IOCM group (n = 13 per group), with iopamidol and iodixanol injection, respectively (4 g iodine/kg). MRI including IVIM and DKI was performed 24 h before contrast medium injections (baseline) and 1, 24, 48, and 72 h after injections. Changes in pure molecular diffusion (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), mean diffusion (MD), mean kurtosis (MK), serum creatinine (SCr) and urea nitrogen (BUN), histopathology alterations, and α-smooth muscle actin (α-SMA) expression were assessed. Inter-observer agreement was evaluated using the intraclass correlation coefficient (ICC).

Results

Compared against baseline levels, significant decreases in D, D*, and f were observed in all anatomical kidney compartments after contrast injection (p < 0.05). MD in the cortex (CO) and outer medullary (OM) gradually decreased, and MK in OM gradually increased 24–72 h after injection. D, D*, f, and MD were negatively correlated with the histopathologic findings and α-smooth muscle actin (α-SMA) expression in all anatomical kidney compartments. Inter-observer reproducibility was generally good (ICCs ranging from 0.776 to 0.979).

Conclusions

IVIM and DKI provided noninvasive imaging parameters, which might offer effective detection of CI-AKI in DN.

Low-Osmolar vs. Iso-Osmolar Contrast Media on the Risk of Contrast-Induced Acute Kidney Injury: A Propensity Score Matched Study

Objective:

Among the various risk factors associated with contrast-induced acute kidney injury (CI-AKI), the importance of osmolality and viscosity is emerging among the characteristics of contrast media (CM) itself. High osmolality CM (HOCM) is deprecated and low osmotic pressure (LOCM) and iso-osmotic pressure (IOCM) are mainly used in clinical situations where the results of studies on their effect on the development of CI-AKI are contradictory. We evaluated the association between the type of CM and the risk of CI-AKI.

Materials and Methods

A retrospective observational cohort study to analyze the effect of the type of CM on the development of CI-AKI. Using propensity score (PS) matching, 2,263 LOCM and IOCM groups were paired for analysis from 5,267 patients and fulfilled the inclusion criteria among 12,742 patients who underwent CAG between 1 January 2007, and 31 December 2016. LOCM included iopromide and iopamidol, IOCM was iodixanol. CI-AKI, which was the primary endpoint, was defined based on the Kidney Disease Improving Global Outcomes criteria within 48 h after exposure to the CM. A multivariable logistic regression analysis was used in the unmatched and matched cohorts, respectively. In addition, a stratified model on clinically important variables, including a high Mehran score (≥ 6), was also used in the matched cohort.

Results

LOCM users showed an increased incidence of CI-AKI (11.7% vs. 9.3%; p = 0.006), but it lost statistical significance after PS matching (9.9% vs. 9.5%, p = 0.725). In multivariable analyses, the adjusted odds ratio for CI-AKI in the LOCM group were 1.059 [95% confidence interval (CI) = 0.875–1.282; p = 0.555] in unmatched cohort and 0.987 (95% CI = 0.803–1.214; p = 0.901) in matched cohort. These results were also consistent with the high-risk (high Mehran score) group.

Conclusions

Although the role of CM types in the development of CI-AKI has been debated, our observation shows that the selection between LOCM and IOCM during CAG has no influence on the incidence of CI-AKI.

Effects of a High Dose of the Contrast Medium Iodixanol on Renal Function in Patients Following Percutaneous Coronary Intervention

Iodixanol is associated with lower rates of contrast-induced acute kidney injury (CI-AKI). However, the effects of high volumes of iodixanol on renal function after percutaneous coronary intervention (PCI) have not been fully elucidated. This study evaluates the effects of high-dose (>300 mL) iodixanol on renal function within 72 hours of PCI. We retrospectively reviewed 676 consecutive patients who received high-dose (>300 mL) iodixanol during PCI between October 2015 and December 2017 in 4 centers. Logistic regression analysis was used to identify significant independent predictors for CI-AKI. The incidence of CI-AKI was 3.5% (23/651). In patients administered 300 to 500 mL and >500 mL iodixanol, the incidence of CI-AKI was 3.9% and 1.7%, respectively. In patients with an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m², the incidence of CI-AKI was 2.6%. In high-risk and very high-risk patients, stratified by the Mehran risk score, the incidence of CI-AKI was 3.3% and 4.3%, respectively. In patients received high-dose iodixanol (>300 mL), logistic regression analysis demonstrated that female sex, chronic kidney disease, and eGFR were independent risk factors for CI-AKI, but contrast volume was not. The administration of high (300-500 mL) and very high (>500 mL) dose of iodixanol is associated with low rates of CI-AKI.

Contrast Media-Different Types of Contrast Media, Their History, Chemical Properties, and Relative Nephrotoxicity

History of contrast dates back to the 1890s, with the invention of the radiograph. Nephrotoxicity has been a main limitation in ideal contrast media (CM). High-osmolar contrast media no longer are in clinical use due to overwhelming evidence supporting greater nephrotoxicity with these CM compared with current CM. Contrast-induced nephropathy (CIN) remains a common cause of in-hospital acute kidney injury. The choice contrast agent is determined mainly by cost and institution practice. This review focuses on the history, chemical properties, and experimental and clinical studies on the various groups of CM and their role in CIN.

Application of low-concentration contrast agents and low-tube-voltage computed tomography to chest enhancement examinations: A multicenter prospective study

To evaluate the influence of low-concentration contrast agents and low-tube-voltage computed tomography on chest enhancement examinations, we conducted a multicenter prospective study. A total of 216 inpatients enrolled from 12 different hospitals were randomly divided into four groups: A: voltage, 120 kVp; iohexol, 350 mgI/mL; B: voltage, 100 kVp, iohexol, 350 mgI/mL; C: voltage, 120 kVp, iodixanol, 270 mgI/mL; and D: voltage, 100 kVp, iodixanol, 270 mgI/mL. Subjective image quality was assessed by two radiologists and compared by weighted kappa test. The objective image scores, scanning radiation doses, and pathological coincidence rates were analyzed. There were no significant differences in gender, age, height, weight, and body mass index between the four groups (p > 0.05). The consistency of the radiologists' ratings were good, with kappa value ranging from 0.736 (95% confidence interval: 0.54-0.933) to 0.809 (95% confidence interval: 0.65-0.968), and there was no difference in subjective image score between the four groups. The computed tomography value of group D had no difference with group A. The volume computed tomography dose index, dose length product, and effective dose of group D (6.93 ± 3.03, 241.55 ± 104.75, and 3.38 ± 1.47, respectively) were all significantly lower than those of group A (10.30 ± 4.37, 359.70 ± 152.65, and 5.04 ± 2.14, respectively). There was no significant difference in the imaging diagnosis accuracy rate between the four groups (p > 0.05). The results indicated that low-concentration contrast agents (270 mgI/mL) and low-tube-voltage (100 kVp) computed tomography can not only decrease radiation dose but also guarantee the image quality and meet the needs of imaging diagnosis in chest enhancement examinations, which make it possible for its generalization and application.

Contrast Induced Nephropathy and 2-Year Outcomes of Iso-Osmolar Compared with Low-Osmolar Contrast Media after Elective Percutaneous Coronary Intervention

Background and Objectives

This study investigated the relative incidence of contrast induced nephropathy (CIN) and long-term outcomes between iso-osmolar contrast media (IOCM) and low-osmolar contrast media (LOCM) undergoing elective percutaneous coronary intervention (PCI).

Methods

A total of 9,431 patients receiving elective PCI were enrolled in the cohort. The patients were divided into IOCM group and LOCM group. Propensity score matching (PSM) was applied to minimize the selection bias between groups.

Results

The multivariate analysis showed that the use of IOCM compared with LOCM did not affect the CIN incidence (odds ratio [OR], 0.912; 95% confidence interval [CI], 0.576–1.446; p=0.696). After PSM, the incidence of CIN was 1.5% and 4.0% in IOCM group (n=979) and LOCM group (n=979), respectively, p=0.001. IOCM significantly reduced the incidence of CIN compared with LOCM (OR, 0.393; 95% CI, 0.214–0.722; p=0.003). After 2 years of follow-up, the all-cause mortality was higher in IOCM group than LOCM group (2.1% vs. 0.9%, p<0.001). Cox regression analysis showed IOCM was not independent risk factor of 2-years all-cause mortality (OR, 0.849; 95% CI, 0.510–1.412; p=0.528). After PSM, the difference of all-cause death between groups disappeared (1.7% vs. 1.9%, p=0.739). Cox regression analysis showed that the use of IOCM compared with LOCM did not affect the incidence of 2-year all-cause mortality (OR, 1.037; 95% CI, 0.534–2.014; p=0.915).

Conclusions

Compared with LOCM, IOCM significantly reduced the incidence of CIN after elective PCI, but had no significant effect on 2-year all-cause mortality.

Routine iso-osmolar contrast media use and acute kidney injury following percutaneous coronary intervention for ST elevation myocardial infarction

BACKGROUND

Temporal changes in contrast-induced acute kidney injury (CI-AKI) incidence following primary percutaneous coronary intervention (PPCI) are poorly defined. Additionally, the benefits of iso-osmolar contrast media (IOCM) compared to low osmolar CM (LOCM) are uncertain.

METHODS

Using data from a regional PPCI service, temporal changes in baseline risk and annual incidence of CI-AKI were studied. A CM protocol change occurred in 2013 allowing a comparison of the incidence of CI-AKI between LOCM (2012-13) and IOCM (2013-15).

RESULTS

Between 2012 and 2015, 208 of 1310 patients experienced CI-AKI (15.9%). The Mehran AKI risk score did not change during the study period although there was an increase in the incidence of CI-AKI in later study years (P<0.001 for trend) when IOCM was used. Factors independently associated with CI-AKI were IOCM use (OR=1.96, [95% CI: 1.39-2.75]), age per year (OR=1.02, 95% CI: 1.01-1.04), baseline creatinine per µmol/L (OR=1.006, 95% CI: 1.003-1.01) and contrast volume per milliliter (OR=1.002, 95% CI: 1.001-1.004). The baseline characteristics of patients treated using IOCM (N.=783) vs. LOCM (N.=527) were similar (Mehran Score 6.6 vs. 6.9, P=0.173) but CI-AKI occurred more frequently with IOCM compared to LOCM (19.2% vs. 11.2%, P<0.001). Use of IOCM was independently associated with CI-AKI (OR=1.98, 95% CI: 1.339-2.774, P<0.001) with consistency across all sub-groups of age, gender, baseline creatinine, contrast volume, shock and diabetes. The adjusted in-hospital mortality was increased with IOCM compared to LOCM (OR=3.03, 95% CI: 1.313-6.994, P=0.009).

CONCLUSIONS

IOCM use was observed to be associated with an increased occurrence of CI-AKI, and an increase in in-hospital mortality after primary PCI.

Ultra-low contrast coronary angiography and zero-contrast percutaneous coronary intervention for prevention of contrast-induced nephropathy: step-by-step approach and review

Contrast-induced nephropathy is a serious complication after intravascular administration of iodinated contrast media and is associated with numerous adverse outcomes. Its prevalence is particularly high in patients with multiple comorbidities who undergo coronary angiography and percutaneous coronary intervention (PCI). Currently, the only effective method to prevent contrast-induced kidney injury is adequate hydration and a reduction of contrast volume during the intervention. Recently, new approaches aiming to minimize contrast usage have been proposed, i.e., ultra-low contrast angiography and zero-contrast PCI. However, neither tutorials for these techniques nor reviews of their outcomes exist in the literature, and therefore dissemination of these approaches among the interventional community may be limited. This article presents a step-by-step description on how to perform ultra-low coronary angiography and zero-contrast PCI, which should help invasive cardiologists to adopt these techniques in daily practice. A review of clinical studies, case series and single case reports regarding these methods is also provided. Despite the promising results, such procedures still require some improvements and confirmation of their effectiveness as well as safety in large clinical studies. This article aims to spread these new techniques throughout the interventional community, which is paramount for their further development and wider utilization.

Comparative effect of iso-osmolar versus low-osmolar contrast media on the incidence of contrast-induced acute kidney injury in diabetic patients: a systematic review and meta-analysis

BACKGROUND

Contrast-induced acute kidney injury (CI-AKI) is a major adverse effect caused by intravascular administration of iodinated contrast medium. Whether there is a difference in CI-AKI incidence between iso-osmolar (IOCM) and low-osmolar contrast media (LOCM) among diabetic patients is controversial.

METHODS

Randomized controlled trials comparing the nephrotoxic effects between IOCM and LOCM in diabetic patients with or without CKD (eGFR< 60 ml/min/1.73 m2) were included in the analysis. The incidence of CI-AKI was defined as an initial increase in serum creatinine (SCr) concentration of at least 0.5 mg/dl or a rise in creatinine of 25% from baseline.

RESULTS

A total of 2190 patients were included, among whom 1122 patients received IOCM and 1068 received LOCM. When compared to LOCM, IOCM had no significant benefit in preventing CI-AKI (OR = 1.66, [CI: 0.97-2.84], P = 0.06, I2 = 54%). However, the difference between IOCM and LOCM was found when CI-AKI was defined as an absolute SCr increase (≥0.5 mg/dl) rather than a relative SCr increase (≥25%). Further analysis showed that LOCM resulted in more adverse events.

CONCLUSIONS

Whether there is a difference of CI-AKI incidence between IOCM and LOCM in diabetic patients was related to the selected diagnostic criteria. The incidence of adverse events was significantly lower with IOCM when compared with LOCM. Therefore, we suggest that IOCM may be used in diabetic and CKD (eGFR< 60 ml/min/1.73 m2) patients.

Differences in Adverse Reactions Among Iodinated Contrast Media: Analysis of the KAERS Database

BACKGROUND

The various adverse drug reactions (ADRs) arise from different types of iodinated contrast media (ICM).

OBJECTIVE

Thus, we investigated the occurrence rate and types of ADRs according to the total usage cases of the 7 most common ICM.

METHODS

We retrospectively reviewed 74,242 causal ADRs caused by ICM from the Korea Adverse Event Reporting System database between January 2014 and December 2016. The 11,712,796 total usage cases that represent all administrations of ICM reported from individual medical institutions were received from the Health Insurance Review and Assessment Service. A proportionality test was used to examine the differences in the frequency ratio of causal ADRs to total usage cases.

RESULTS

Immediate hypersensitivity (44,467 cases, 88.56%) occurred more frequently than delayed hypersensitivity (5,725 cases, 11.4%; P < .001). The overall occurrence rate of causal ADRs and serious ADRs considering total usage cases was 0.37% and 0.02%, respectively (P < .001). The ICM most commonly resulting in ADRs were iomeprol (0.7%) and iopromide (0.59%). The serious ADRs were most common for iomeprol (0.05%). When ADRs were classified according to the system organ class, "skin and appendages disorders" (47,065 cases, 63.4%) occurred most common. Iodixanol resulted in the highest frequency of "urinary system disorders."

CONCLUSIONS

By comparison of the ADRs considering total usage cases, the incidence and classification of ADRs were different for each contrast medium. A prospective study is needed because the differences in these 7 major contrast media may assist in the selection of ICM tailored for each patient.

Iodixanol versus iopromide in patients with renal insufficiency undergoing coronary angiography with or without PCI

BACKGROUND

The use of contrast agents during coronary angiography can result in contrast-induced nephropathy (CIN), particularly in patients with renal dysfunction. On the contrary, different contrast agents can induce different degree of changes in cardiac function. The objective of our meta-analysis was to compare the clinical safety of iso-osmolar contrast medium iodixanol to low-osmolar contrast medium iopromide in patients with renal insufficiency undergoing coronary angiography with or without percutaneous coronary intervention (PCI).

METHODS

We searched Medline, Embase, Cochrane Library, and reference lists to identify randomized controlled trials that compared iodixanol to iopromide with the incidence of CIN as an endpoint in renal impaired patients undergoing coronary angiography. Outcome measures were the incidence of CIN, absolute peak serum creatinine (Scr) increase from baseline and a composite of cardiovascular adverse events.

RESULTS

A total of 8 trials with 3532 patients were pooled; 1759 patients received iodixanol and 1773 patients received iopromide. There was no significant difference in the incidence of CIN (summary odds ratio [OR] 0.50, 95% confidence interval [CI] 0.19-1.35, P = .17) and peak Scr increase (mean difference -0.01 mg/dL, 95% CI -0.08 to 0.05, P = .69) when iodixanol was compared with iopromide. But iodixanol was associated with a statistically significant reduction in cardiovascular adverse events when compared with iopromide (OR 0.47, 95% CI 0.30-0.73, P = .0009).

CONCLUSIONS

Analysis of pooled data from 8 randomized controlled trials of iodixanol against iopromide in patients with renal insufficiency undergoing coronary angiography with or without PCI showed that iodixanol nonsignificantly reduced the incidence of CIN, but was associated with a significantly reduced risk of cardiovascular adverse events when compared with iopromide.

Are iso-osmolar, as compared to low-osmolar, contrast media cost-effective in patients undergoing cardiac catheterization? An economic analysis

PURPOSE

Contrast-induced acute kidney injury is a prominent complication following cardiac catheterization, though the risk has progressively decreased in recent times with appropriate risk stratification and use of safer contrast agents. Despite data supporting further lowering of risk with the iso-osmolar agent, iodixanol, uptake has lagged, perhaps due to increased upfront cost of this agent. We undertook an economic analysis to estimate the cost-effectiveness of a strategy utilizing iodixanol compared to using a low-osmolar contrast agent.

METHODS

We created a Markov model to evaluate the two strategies, and included a differential relative risk of contrast-induced acute kidney injury, based on a systematic review of the literature. Downstream clinical events, including need for dialysis and mortality, were modeled using data from existing published literature. A third-party payer perspective was utilized for the analysis and presentation of the primary economic analysis.

RESULTS

The strategy of using iodixanol dominated in both the low-risk and high-risk base case analyses. However, the difference was quite small in the low-risk scenario (lifetime cost: C$678,034 vs. C$678,059 and life expectancy: 19.80 vs. 19.72 years). The difference was more marked (life expectancy 15.65 vs. 14.15 years and cost C$680,989 vs. C$682,023) in the high-risk case analysis. This was robust across most of the variables tested in sensitivity analyses.

CONCLUSION

The use of iodixanol, compared with low-osmolar contrast agents, for cardiac catheterization, results in a small benefit clinical outcomes, and in a savings in direct healthcare costs. Overall, our analysis supports the use of iodixanol for cardiac catheterization, especially in patients at high risk of acute kidney injury.

Iso-Osmolar Iodixanol Induces Less Increase in Circulating Endothelial Microparticles In Vivo and Less Endothelial Apoptosis In Vitro Compared with Low-Osmolar Iohexol

Background and Aims

There is no consensus on whether iodixanol is superior to iohexol. This study aimed to compare the effects of iodixanol and iohexol on circulating endothelial microparticles (EMPs) in stable coronary artery disease (CAD) patients with diabetes mellitus (DM), and also their cytotoxic effects on human umbilical vein endothelial cells (HUVECs) in vitro.

Methods

100 CAD patients with DM were randomly assigned to receive iso-osmolar contrast medium iodixanol (group I) or low-osmolar iohexol (group II) during coronary angioplasty. An additional 49 CAD patients without DM receiving iohexol were recruited as group III. Circulating CD31+/CD41a- EMPs, CD62E+ EMPs, and CD31+/CD41a+ platelet microparticles (PMPs) were determined by flow cytometry. In vitro, the cytotoxic effects of iodixanol and iohexol on HUVECs were determined.

Results

Circulating CD31+/CD41a- EMPs and PMPs were significantly increased after angioplasty in all 3 groups, while CD62E+ EMPs significantly decreased in group I. CD31+/CD41a- EMPs and PMPs were significantly higher in group II than group I or III. In vitro, both contrast media induced EMP release and inhibited the viability and induced apoptosis of HUVECs, as well as increasing Bax and cleaved caspase-3 and decreasing Bcl-2. The above effects were less evident in iodixanol than in iohexol.

Conclusions

Compared with iohexol, iodixanol induces less release of EMPs in both CAD patients with DM during angioplasty and in vitro HUVEC culture, which is associated with less pronounced proapoptotic effects of iodixanol on HUVECs.

Clinical Study Registration Number

This study is registered with ChiCTR-TRC-14005183.

Iso-osmolar contrast media and adverse renal and cardiac events after percutaneous cardiovascular intervention

Aim: To assess the relationship between type of contrast media (CM), iso-osmolar contrast media (IOCM) or low-osmolar contrast media (LOCM), and major adverse renal and cardiovascular events (MARCE). Materials & methods: Coronary or peripheral angioplasty visits were stratified into CM cohorts: IOCM or LOCM. Multivariable regression analysis used hospital fixed effects to assess the relationship between MARCE events and type of CM. Results: Among 333,533 visits (357 hospitals), the incidence of MARCE was 7.41%. After controlling for observable and unobservable time invariant within-hospital characteristics, administration of IOCM versus LOCM was associated with a 0.69% absolute and 9.32% relative risk reduction in MARCE rate. Conclusion: Our study indicates that as compared with LOCM, IOCM may be associated with reduction of MARCE events in coronary or peripheral angioplasty patients.

Contrast-induced nephropathy in patients with diabetes mellitus between iso- and low-osmolar contrast media: A meta-analysis of full-text prospective, randomized controlled trials

Purpose

This study was conducted to compare iso-osmolar contrast medium, iodixanol, with low-osmolar contrast media (LOCM) for assessing contrast-induced nephropathy (CIN) incidence, exclusively in the diabetic population.

Method

A systematic search was conducted for full-text, prospective, randomized controlled trials (RCTs). The primary outcome was incidence of CIN. Medline, Cochrane Central Register of Controlled Trials, and other sources were searched until May 31, 2017.

Results

Twelve RCTs finally met the search criteria. Iodixanol did not significantly reduce the risk of CIN (risk ratio [RR]: 0.72, 95% confidence interval (CI): [0.49, 1.04], p = 0.08). However, there was significantly reduced risk of CIN when iodixanol was compared to a LOCM agent iohexol (RR: 0.32, 95% CI [0.12, 0.89]). There were no differences between iodixanol and the other non-iohexol LOCM (RR: 0.92, 95% CI [0.68, 1.25]).

Conclusion

In diabetic populations, iodixanol is not associated with a significant reduction of CIN risk. Iodixanol is associated with a reduced risk of CIN compared with iohexol, whereas no significant difference between iodixanol and other LOCM could be found.

Prediction of contrast induced acute kidney injury using novel biomarkers following contrast coronary angiography

BACKGROUND/INTRODUCTION

Chronic kidney disease (CKD) is a risk factor for contrast induced acute kidney injury (CI-AKI). Contrast angiography in CKD patients is a common procedure. Creatinine is a delayed marker of CI-AKI and delays diagnosis which results in significant morbidity and mortality.

AIM

Early diagnosis of CI-AKI requires validated novel biomarkers.

DESIGN

A prospective observation study of 301 consecutive CKD patients undergoing coronary angiography was performed.

METHODS

Samples for plasma neutrophil gelatinase-associated lipocalin (NGAL), serum liver fatty acid-binding protein (L-FABP), serum kidney injury marker 1, serum interleukin 18 and serum creatinine were taken at 0, 1, 2, 4, 6 and 48 h post-contrast. Urinary NGAL and urinary cystatin C were collected at 0, 6 and 48 h. Incidence of major adverse clinical events (MACE) was recorded at 1 year. CI-AKI was defined as an absolute delta rise in creatinine of ≥26.5 µmol/l or a 50% relative rise from baseline at 48 h following contrast.

RESULTS

CI-AKI occurred in 28 (9.3%) patients. Plasma NGAL was most predictive of CI-AKI at 6 h. L-FABP performed best at 4 h. A combination of Mehran score > 10, 4 h L-FABP and 6 h NGAL improved specificity to 96.7%. MACE was statistically higher at 1 year in CI-AKI patients (25.0 vs. 6.2% in non-CI-AKI patients).

DISCUSSION/CONCLUSION

Mehran risk score, 4 h serum L-FAPB and 6 h plasma NGAL performed best at early CI-AKI prediction. CI-AKI patients were four times more likely to develop MACE and had a trebling of mortality risk at 1 year.

Current Radiographic Iodinated Contrast Agents

Millions of radiologic examinations requiring the use of iodinated contrast are performed yearly in North America. Triiodobenzoic acid, the contrast agent molecule currently in use, is a benzene ring covalently bonded to the 3 iodine atoms. Iodinated contrast media can be divided in 4 categories: ionic monomers, ionic dimers, nonionic monomer, and nonionic dimers. Currently, second- and third-generation nonionic low-osmolar and iso-osmolar contrast media are used in clinical practice. The search for a safer and more effective iodinated contrast agents remains an ongoing challenge and important research topic.

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.

Intravenous Contrast: Friend or Foe? A Review on Contrast-Induced Nephropathy

Intravenous iodinated contrast is used in many contrasted imaging studies ranging from computed tomography to angiography. The risks of contrast-induced nephropathy (CIN) and its incidence have not been clearly defined. Most iodinated contrast media used today are hypertonic compared with serum osmolality and pose biological risks. However, the risk of CIN in the general population may be overestimated. Confounding risk factors may contribute to acute kidney injury other than attributable risk of contrast exposure. In high-risk populations such as in those with CKD, CIN risk may be higher and thus caution should be exerted with contrast exposure. The volumes of contrast should be minimized as much as possible and hemodynamic status should be optimized before contrast administration.

Comparison of the nephrotoxic effects of iodixanol versus iohexol in patients with chronic heart failure undergoing coronary angiography or angioplasty

OBJECTIVES

The aim of this clinical trial is to compare iodixanol with iohexol for the incidence of contrast-induced nephropathy in patients with chronic heart failure with reduced ejection fraction who are currently undergoing coronary angiography or angioplasty.

METHODS

The clinical trial included 220 consecutive patients with chronic heart failure with reduced ejection fraction undergoing coronary angiography or angioplasty. Study participants were administered either iodixanol (n = 110) or iohexol (n = 110). The primary study endpoint was the incidence of contrast-induced nephropathy within 72 h after the procedure. The secondary endpoints were to determine the peak increase in serum creatinine levels and Cystatin C, and the peak decrease in estimated glomerular filtration rate at 72 h post-contrast medium.

RESULTS

Baseline demographic and clinical characteristics of the patients were similar between the two groups. Our study showed that the overall incidence of contrast induced nephropathy in patients with chronic heart failure was 20.9%. The incidence of contrast induced nephropathy was significantly lower in iodixanol group than in iohexol group (29.1% vs 12.7%, P = 0.041). The peak increase in serum creatinine levels and the peak decrease in estimated glomerular filtration rate after the procedure were statistically significant between the two groups. Moreover, there was statistically significance in the peak increase of Cystatin C levels after the procedure.

CONCLUSIONS

In patients with chronic heart failure with reduced ejection fraction who are currently undergoing coronary angiography with or without percutaneous coronary intervention, the iso-osmolar contrast iodixanol was associated with a lower incidence of contrast induced nephropathy than low-osmolar contrast iohexol.

Lower incidence of contrast-induced nephropathy in patients undergoing fluorescent angiography

Background

To evaluate the incidence and risk factors of contrast-induced nephropathy (CIN) in patients undergoing fluorescein angiography (FA).

Methods

One hundred sixty patients who underwent FA as a part of ophthalmic examination and had serum creatinine (SCr) results within 24 h before FA and within 72 h after FA between 2005 and 2013 at a tertiary medical center were included. According to baseline SCr levels, the subjects were divided into low-risk group (<1.5 mg/dL), intermediate-risk group (1.5–2.0 mg/dL), and high-risk group (>2.0 mg/dL) for CIN development. The CIN incidence, and changes in renal function defined by SCr levels and estimated glomerular filtration rate (eGFR) were evaluated. Demographics and comorbidities were analyzed to investigate an association with CIN development.

Results

Of 160 patients, 91 were males (56.9%). The mean age was 52.46 ± 17.81 years. Two (1.3%) patients developed CIN after FA, whose SCr levels returned to normal within 10 days without hemodialysis. Overall, there were no changes before and after FA in SCr level (1.52 ± 1.31 mg/dL vs. 1.51 ± 1.28 mg/dL, respectively; p = 0.93) and eGFR (67.02 ± 36.62 mL/min/1.73 m² vs. 66.41 ± 36.54 mL/min/1.73 m², respectively; p = 0.54). SCr level and eGFR remained unchanged after FA in low-risk and intermediate-risk groups. In high-risk group, eGFR remined unchanged, but SCr level decreased after FA (from 3.64 ± 1.59 mg/dL to 3.53 ± 1.60 mg/dL; p = 0.04). Basline SCr and cormorbidities did not predict CIN development.

Conclusions

Acute renal function deterioration was not evident in patients undergoing FA regardless of baseline renal function and comorbidities.

Comparison of 270 Versus 320 mg I/mL of Iodixanol in 1 Image Assessment of Both Renal Arteries and Veins With Dual-Energy Spectral CT Imaging in Late Arterial Phase and Their Influence on Renal Function

OBJECTIVE

The objective of this study was to compare the image quality of renal arteries and veins with dual-energy spectral computed tomography (CT) imaging in late arterial phase using 270 and 320 mg I/mL of iodixanol and their influence on renal function.

METHODS

A total of 1062 patients underwent renal CT angiography with 270 or 320 mg I/mL of iodixanol with dual-energy spectral CT imaging in late arterial phase. Image quality and their influence on renal function were compared.

RESULTS

There were no significant differences of CT value, signal-to-noise ratio, contrast-to-noise ratio, and subjective score of renal vessels between 2 groups (all P > 0.05). The incidence of contrast-induced nephropathy in patients with abnormal renal function using 320 mg I/mL of iodixanol was significantly higher than using 270 mg I/mL of iodixanol (P = 0.043).

CONCLUSIONS

The renal arteries and veins can be fully assessed in late arterial phase with 270 mg I/mL of iodixanol using dual-energy spectral CT scan with better preserved renal function.

Microvascular resistance in response to iodinated contrast media in normal and functionally impaired kidneys

Contrast‐induced nephropathy (CIN) is considered to result from intrarenal vasoconstriction, and occurs more frequently in impaired than in normal kidneys. It was hypothesized that iodinated contrast media would markedly change renal blood flow and vascular resistance in functionally impaired kidneys. Thirty‐six patients were enrolled (32 men; mean age, 75.3 ± 7.6 years) undergoing diagnostic coronary angiography and were divided into two groups based on the presence of chronic kidney disease (CKD), defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min per 1.73 m² (CKD and non‐CKD groups, n = 18 in both). Average peak velocity (APV) and renal artery resistance index (RI) were measured by Doppler flow wire before and after administration of the iodinated contrast media. The APV and the RI were positively and inversely correlated with the eGFR at baseline, respectively (APV, R = 0.545, P = 0.001; RI, R = −0.627, P < 0.001). Mean RI was significantly higher (P = 0.015) and APV was significantly lower (P = 0.026) in the CKD than in the non‐CKD group. Both APV (P < 0.001) and RI (P = 0.002) were significantly changed following contrast media administration in the non‐CKD group, but not in the CKD group (APV, P = 0.258; RI, P = 0.707). Although renal arterial resistance was higher in patients with CKD, it was not affected by contrast media administration, suggesting that patients with CKD could have an attenuated response to contrast media.

Blunted renal vasoconstriction in patients with subclinical contrast-induced renal injury

Contrast media are considered to cause acute kidney injury by activating various factors that induce renal vasoconstriction. We analysed the renal microvascular haemodynamic response using the Doppler flow wire method. Then changes in urinary liver-type fatty acid-binding protein levels following contrast medium administration were compared between groups with or without a micro-injury of the kidney. In the group without renal micro-injury, the average peak velocity (APV) decreased significantly, whereas the renal artery resistance index (RI) increased significantly following contrast medium administration. In contrast, there was no significant change in either the APV or RI in the group with a renal micro-injury. A blunted microvascular response was found in the micro-injury group, whereas microvascular resistance increased in the non-micro-injury group.

Utility of dual-energy spectral CT and low-iodine contrast medium in DIEP angiography

OBJECTIVE

To evaluate the utility of dual-energy spectral computed tomography (CT) and low-iodine intake in CT angiography (CTA) of deep inferior epigastric perforator (DIEP) flaps.

METHODS

In this prospective study, 40 patients with a BMI <28.0 kg/m(2) underwent CTA examination for breast reconstruction and were randomly assigned into two groups (n=20 for each group) as follows: Group A was submitted to dual-energy spectral CT and iodixanol (270 mg I/mL) and Group B was submitted to conventional high iodine contrast agent iohexol (350 mg I/mL). The volume CT dose index (CTDIvol ) and dose length product were recorded and the effective dose (ED) was calculated. The best mono-spectrum images of Group A were selected according to the optimal contrast to noise ratio (CNR). Both mono-spectrum images of Group A and polychromatic images of Group B were used to reconstruct maximum intensity projection (MIP) and volume rendering (VR) images of the perforating artery, respectively. Two radiologists evaluated subjective image quality using a 4-point score. The diameter of the perforating artery, CT value and SD value for the common femoral artery were measured and the CNR was calculated. The total iodine intake and radiation doses of the two groups were calculated and compared.

RESULTS

The best mono-spectrum energy with the optimal CNR of the perforating artery was 63 keV. The CT value of common femoral artery in Group A (380.96±42.75HU) was 7.40% higher than in Group B (354.71±42.01 HU) but with no statistical significance (P>.05). The CNR of the common femoral artery in Group A (23.84±6.73) was 6.88% lower than in Group B (25.60±6.20), with no significant difference (P>.05). The diameters of the perforator vessels were 2.44±0.15 and 2.49±0.14 mm, respectively, with no significant difference (P>.05). Subjective image qualities for the two groups were both good for diagnostics, and the scores for Group A and Group B were (3.88±0.28) and (3.93±0.18), respectively. The scores of the two radiologists were consistent (kappa=0.634). The effective radiation dose in Group A (9.09±0 mSv) was 10.62% lower than in Group B (10.17±1.91 mSv). The total iodine intake in Group A (27 000 mg) was 22.86% lower than in Group B (35 000 mg).

CONCLUSIONS

The combination of dual-energy spectral CT and low-iodine intake in CTA of DIEP flap examination with the optimal CNR technology can meet the requirements of clinical diagnostics, with a 22.86% reduction in total iodine intake and an 11.01% reduction in radiation dose.

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.

Coronary artery calcification scores improve contrast-induced nephropathy risk assessment in chronic kidney disease patients

BACKGROUND

Coronary artery calcification (CAC) is an independent predictor of cardiovascular morbidity and mortality in chronic kidney disease (CKD) patients. The aim of the present study was to evaluate the predictive value of CAC scores for the incidence of contrast-induced nephropathy (CIN) after cardiac catheterization in non-dialyzed CKD patients.

METHODS

The present study evaluated a total of 140 CKD patients who underwent cardiac catheterization. Patients were stratified into two groups based on the optimal cut-off value of the CAC score, which was graded by a non-triggered, routine diagnostic chest computed tomography scan: CAC score ≥8 (high CAC group); and CAC score <8 (low CAC group). CIN was defined as an increase of >10 % in the baseline serum cystatin C level at 24 h after contrast administration.

RESULTS

The mean estimated glomerular filtration rate levels were 41.1 mL/min/1.73 m², and the mean contrast dose administered was 37.5 mL. Patients with high CAC scores exhibited a higher incidence of CIN than patients with low CAC scores (25.5 vs. 3.2 %, p < 0.001). After multivariate adjustment for confounders, the CAC score predicted CIN (odds ratio 1.68, 95 % confidence interval 1.28-2.21, p < 0.001). Moreover, the C-index for CIN prediction significantly increased when the CAC scores were added to the Mehran risk score (0.855 vs. 0.760, p = 0.023).

CONCLUSION

CAC scores, as evaluated using semi-quantitative methods, are a simple and powerful predictor of CIN. Incorporating the CAC score in the Mehran risk score significantly improved the predictive ability to predict CIN incidence.

Imaging patients with renal impairment

Imaging with intravascular contrast media is generally considered safe, particularly in patients without renal failure. However, as renal function deteriorates, the potential risk of nonallergic-type adverse events increases. This presents a unique challenge, particularly when the use of intravenous contrast media is deemed essential for diagnostic purposes. Following a discussion regarding the definition and epidemiology of kidney injury, this review focuses on the evolving understanding of both contrast-induced nephropathy and nephrogenic systemic fibrosis and discusses preventative strategies aimed at minimizing the risk of developing these entities. Alternative non-contrast imaging techniques are also discussed.

Effect of Angiotensin-Converting Enzyme Inhibitors in Contrast-Induced Nephropathy: A Meta-Analysis

AIMS

The purpose of this study was to evaluate the effect of angiotensin-converting enzyme inhibitors (ACEIs) on contrast-induced nephropathy (CIN) in patients undergoing coronary angiography or percutaneous coronary intervention (PCI).

METHODS

We searched the Medline, Embase, Cochrane Library, China National Knowledge Infrastructure, Chongqing VIP database and Wanfang database up to December 2014. Pooled risk ratios (RRs) or weighted mean difference (WMD) with their 95% CIs for the CIN incidence, serum creatinine (SCr), estimated glomerular filtration rate (eGFR) and blood urea nitrogen (BUN) of the patients were collected and calculated using the software Review Manager 5.2.

RESULTS

A total of 12 separate studies including 1,868 patients (1,011 ACEI cases and 857 controls) were considered in the meta-analysis. The overall RR of the incident CIN in the ACEI group vs. the control group was 0.95 (95% CI 0.57-1.58), and the total WMDs of the x0394;SCr, x0394;eGFR and x0394;BUN were -0.01 (95% CI -0.04 to 0.02), 5.71 (95% CI -0.66 to 12.09) and 0.78 (95% CI -0.16 to 1.73), respectively. Besides, the RR of CIN incidence in the captopril group vs. the control group was 0.72 (95% CI 0.25-2.05, p = 0.54), and the pooled WMD of the x0394;SCr was -0.13 (95% CI -0.21 to -0.06, p < 0.01).

CONCLUSION

This meta-analysis suggests that ACEIs administration has no significant influence in the CIN of patients undergoing coronary angiography or PCI; however, captopril might have the potential to prevent CIN.

Novel Biomarkers of Acute Kidney Injury After Contrast Coronary Angiography

Acute kidney injury (AKI), defined as a rise in serum creatinine of greater than 25% from baseline measured at 48 hours after renal insult, may follow iodinated contrast coronary angiography. Termed contrast-induced nephropathy, it can result in considerable morbidity and mortality. Measurement of serum creatinine as a functional biomarker of glomerular filtration rate is widely used for detection of AKI, but it lacks sensitivity for the early diagnosis of AKI (typically rising 24 hours after functional loss) and, as a solely functional marker of glomerular filtration rate, is unable to differentiate among the various causes of AKI. These intrinsic limitations to creatinine measurement and the recognition that improved clinical outcomes are linked to a more timely diagnosis of AKI, has led investigators to search for novel biomarkers of "early" kidney injury. Several studies have investigated the utility of renal injury biomarkers in a variety of clinical settings including angiography/percutaneous coronary intervention, coronary artery bypass graft surgery, sepsis in intensive care patients, and pediatric cardiac surgery. In this article, we discuss the use of iodinated contrast for coronary procedures and the risk factors for contrast-induced nephropathy, followed by a review the potential diagnostic utility of several novel biomarkers of early AKI in the clinical settings of coronary angiography/percutaneous coronary intervention. In particular, we discuss neutrophil gelatinase associated lipocalin in depth. If validated, such biomarkers would facilitate earlier AKI diagnosis and improve clinical outcomes.