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

Iodixanol-associated acute kidney injury and prognosis in patients undergoing elective percutaneous coronary intervention: a prospective, multi-center study

OBJECTIVE

To evaluate iodixanol-associated acute kidney injury (AKI) and prognosis in patients undergoing elective percutaneous coronary intervention (PCI).

METHODS

Patients undergoing elective PCI and iodixanol administration were prospectively enrolled in 8 centers between May 2020 and November 2021. The primary endpoint was AKI, defined as an increase in SCr of ≥ 0.3 mg/dL (26.4 μmol/L) or relative elevation ≥ 50% from baseline in the 48-72 h after PCI. Prognosis evaluations included the major adverse renal and cardiovascular events (MARCE): all-cause mortality, new-onset renal replacement therapy (NRRT), non-fatal myocardial infarction, and non-fatal stroke. AKI predictors were identified using multivariable logistic regression and associations between AKI and outcomes were examined using Cox regression.

RESULTS

A total of 3630 patients were included in the final analysis and 2.9% of patients (107/3,630) suffered AKI. Among them, 95.3% (102/107) of AKI were stage 1, and 4.6% (5/107) of stage 2. The multivariable analysis indicated that age over 75-year-old, diabetes, NT-pro-BNP > 300 pg/mL, hemoglobin < 110 g/L, eGFR < 60 mL/min/1.73m2, and diuretics were independently associated with AKI (p < 0.05). After a median follow-up of 13 months, MARCE occurred in 3.6% (131/3630) of the study population, and their incidence was higher in AKI (9.4%, 10/107) vs. non-AKI patients (3.4%, 121/3,523). However, after multivariable adjustment, there was no statistically significant association between AKI and MARCE (p = 0.382).

CONCLUSIONS

In patients undergoing elective PCI, cases of iodixanol-associated AKI were mostly mild and, after multivariable adjustment, held no statistically significant association with MARCE on mid-term follow-up.

CLINICAL RELEVANCE STATEMENT

The incidence of iodixanol-associated AKI was low and mainly limited to mild renal impairment in patients undergoing elective PCI. Physicians should provide adequate contrast for coronary artery evaluation and, at the same time, minimize the contrast volume.

KEY POINTS

• The incidence of iodixanol-associated acute kidney injury was low and mostly limited to mild renal impairment. • Iodixanol administration had no statistically significant impact on the major adverse renal and cardiovascular events in patients undergoing elective percutaneous coronary intervention.

Key Considerations regarding the Renal Risks of Iodinated Contrast Media: The Nephrologist's Role

BACKGROUND

The administration of iodinated contrast medium during diagnostic and therapeutic procedures has always been associated with the fear of causing acute kidney injury (AKI) or an exacerbation of chronic kidney disease. This has led, on the one hand, to the deterrence, when possible, of the use of contrast medium (preferring other imaging methods with the risk of loss of diagnostic power), and on the other hand, to the trialling of multiple prophylaxis protocols in an attempt to reduce the risk of kidney injury.

SUMMARY

A literature review on contrast-induced (CI)-AKI risk mitigation strategies was performed, focussing on the recognition of individual risk factors and on the most recent evidence regarding prophylaxis.

KEY MESSAGES

Nephrologists can contribute significantly in the CI-AKI context, from the early stages of the decision-making process to stratifying patients by risk, individualising prophylaxis measures based on the risk profile, and ensuring appropriate evaluation of kidney function and damage post-procedure to improve care.

Iso-osmolar versus low-osmolar contrast media and outcomes after percutaneous coronary intervention: Insights from the VA CART Program

OBJECTIVES

To assess whether contrast media type is associated with outcomes in veterans undergoing percutaneous coronary intervention (PCI).

BACKGROUND

There is uncertainty about the impact of iso-osmolar contrast medium (IOCM) versus low-osmolar contrast medium (LOCM) on acute kidney injury (AKI) and other major adverse renal or cardiovascular events (MARCE) after PCI. We assessed the association between contrast media type and MARCE in patients who underwent PCI within the Veterans Administration Healthcare System.

METHODS

We reviewed PCIs performed between 2009 and 2019 using data from the Veterans Affairs Clinical Assessment, Reporting, and Tracking Program. The primary endpoint was MARCE, a composite of myocardial infarction, stroke, all-cause death, AKI, and dialysis onset at 30 days.

RESULTS

The analysis cohort consisted of 50,389 patients of whom 25,555 received LOCM and 24,834 received IOCM. There was significant variation in contrast type across sites. After adjustment for comorbidities, no significant association between contrast media type and MARCE was observed in both site-unadjusted (odds ratio [OR] for IOCM: 0.99; 95% confidence interval [CI]: 0.92-1.08; p = 0.97) and site-adjusted (OR: 1.06; 95% CI: 0.95-1.18; p = 0.30) analyses. Similar results were obtained when contrast volume was imputed or the data was subset to individuals with available contrast volume.

CONCLUSION

In a large cohort of veterans undergoing PCI, we found considerable site variation in the type of contrast media used but no significant association between contrast media type and the incidence of MARCE, both before and after adjustment for the site.

Three-Dimensional Kidney-on-a-Chip Assessment of Contrast-Induced Kidney Injury: Osmolality and Viscosity

Increased viscosity of concentrated contrast media (CM) in the renal tubules can perturb renal hemodynamics and have a detrimental effect on tubular epithelial cells. However, the effects of viscosity on contrast-induced nephropathy (CIN) remain poorly understood. Conventional in vitro culture studies do not reflect the rheological properties of CM. Therefore, we investigated the effects of CM viscosity on renal tubules using a kidney-on-a-chip and two different types of CM. Renal proximal tubule epithelial cells (RPTEC) were cultured in a three-dimensional microfluidic culture platform under bidirectional fluid shear stress. We treated the RPTEC with two types of CM: low- (LOCM, iopromide) and iso-osmolar contrast media (IOCM, iodixanol). Renal tubular cell injury induced by LOCM and IOCM was examined under different iodine concentrations (50–250 mgI/mL) and shear-stress conditions. LOCM showed a significant dose-dependent cytotoxic effect, which was significantly higher than that of IOCM under static and low-to-moderate shear stress conditions. However, high shear-stress resulted in reduced cell viability in IOCM; no difference between IOCM and LOCM was found under high shear-stress conditions. The cytotoxic effects were pronounced at a mean shear stress of 1 dyn/cm2 or higher. The high viscosity of IOCM slowed the fluid flow rate and augmented fluid shear-stress. We suggest an alternative in vitro model of CIN using the three-dimensional kidney-on-a-chip. Our results indicate a vital role of viscosity-induced nephrotoxicity under high shear-stress conditions, contrary to the findings of conventional in vitro studies.

The Pathophysiology and the Management of Radiocontrast-Induced Nephropathy

Contrast-induced nephropathy (CIN) is an impairment of renal function that occurs after the administration of an iodinated contrast medium (CM). Kidney dysfunction in CIN is considered transient and reversible in most cases. However, it is the third most common cause of hospital-acquired acute kidney injury and is associated with increased morbidity and mortality, especially in high-risk patients. Diagnostic and interventional procedures that require intravascular CM are being used with increasing frequency, especially among the elderly, who can be particularly susceptible to CIN due to multiple comorbidities. Therefore, identifying the exact mechanisms of CIN and its associated risk factors is crucial not only to provide optimal preventive management for at-risk patients, but also to increase the feasibility of diagnostic and interventional procedure that use CM. CM induces kidney injury by impairing renal hemodynamics and increasing the generation of reactive oxygen species, in addition to direct cytotoxicity. Periprocedural hydration is the most widely accepted preventive strategy to date. Here, we review the latest research results on the pathophysiology and management of CIN.

Different outcomes between iso-osmolar and low-osmolar contrast media in acute myocardial infarction with renal impairment

BACKGROUND

The selection of appropriate contrast media (CM) remains an important issue in terms of renal preservation in patients with acute myocardial infarction (AMI) and renal impairment scheduled for percutaneous coronary intervention (PCI). We compared the clinical outcomes of patients with AMI and renal impairment, depending on the CM type (iso-osmolar CM [IOCM] vs. low-osmolar CM [LOCM]) that was used during PCI.

METHODS

From the Convergent Registry of Catholic and Chonnam University for Acute Myocardial Infarction, 3174 post-PCI patients with AMI and renal impairment were subdivided into two groups (IOCM [n = 2101] and LOCM [n = 1073]).

RESULTS

Regarding in-hospital clinical outcomes, the IOCM group had a higher peak creatinine (Cr) level and lower "Cr differential" than the LOCM group. A higher proportion of dialysis was noted in the IOCM group. In 30-day clinical outcomes, the IOCM group showed higher incidence of new-onset heart failure (HF) but lower incidence of revascularization than the LOCM group. The differences in in-hospital and 30-day clinical outcomes were attenuated after inverse probability of treatment weighting, except for new-onset HF. All other variables in 30-day clinical outcomes, including all-cause death, non-fatal myocardial infarction, cerebrovascular accidents, stent thrombosis, and any dialysis events, were similar between the two groups.

CONCLUSIONS

IOCM use did not prevent future incidence of dialysis compared to LOCM use in AMI patients with renal impairment.

CHIPS: Prevention of contrast-induced nephropathy before and after cardiac catheterization

ABSTRACT

Contrast-induced nephropathy is the leading cause of acute kidney injury in hospital settings. Practitioners must have a comprehensive understanding of preventive interventions. This article provides a mnemonic NPs can use to prevent contrast-induced nephropathy. The mnemonic, CHIPS, addresses Contrast minimizations, Hemofiltration, Iso-osmolar/low osmolar contrast, Pharmacologic interventions, and Saline I.V. hydration.