Contrast medium induced nephropathy: new insights into prevention and risk management

Utility of the SYNTAX Score in the risk stratification of patients undergoing rotational atherectomy

Introduction

The SYNTAX Score (SS) evaluates the angiographic complexity of coronary artery disease to assess the cardiovascular risk after coronary revascularization. The aim of the study was to evaluate whether SS results are associated with in-hospital and 1-year outcomes of patients undergoing percutaneous coronary intervention (PCI) requiring rotational atherectomy (RA).

Material and methods

We analyzed data of 207 consecutive patients who underwent PCI with RA. Patients were divided into two groups: those with high SS (> 33 points) and those with low/intermediate SS (0–33 points).

Results

In 21 (10%) patients SS was high and 186 (90%) patients had low/intermediate SS. Patients with high SS were older (76 vs. 71 years, p = 0.008) and more frequently diagnosed with chronic kidney disease (38% vs. 18%, p = 0.03) and heart failure (71% vs. 30%, p = 0.0001). In patients with high SS the RA procedure was longer (p = 0.004), required more contrast (p = 0.005) and higher radiation doses (p = 0.04), and contrast-induced nephropathy was more frequent (14% vs. 2%, p = 0.001).

Conclusions

In our RA patients there was no significant difference between the frequency of in-hospital and 1-year adverse cardiovascular events depending on the SS result. High SS correlates only with parameters describing the extensity and technical complexity of the procedure. However, the unavailability of other risk assessment tools in this population raises the need to create a new more specific risk score for patients requiring RA.

Effect of Alprostadil on the Prevention of Contrast-Induced Nephropathy: A Meta-Analysis of 36 Randomized Controlled Trials

Contrast-induced nephropathy (CIN) is the third leading cause of acquired acute renal injury in hospitalized patients. Alprostadil plays a role in the maintenance and redistribution of intrarenal blood flow and the excretion of electrolytes and water. However, the effectiveness of alprostadil in preventing CIN remains controversial. Thirty-six articles with a total of 5495 patients were included in this study. Both groups (experimental group and control group) received standard hydration therapy. In the experimental group, patients received different doses of alprostadil. Serum creatinine (SCr), blood urea nitrogen (BUN), estimated glomerular filtration rate (eGFR), cystatin C, creatinine clearance rate (CCr), and β2-microglobulin (β2-MG) were measured at 24, 48, and 72 hours after contrast media injection. The incidence of CIN in the experimental group was significantly lower than that in the control group (6.56% vs 16.74%). The level of SCr, cystatin C, BUN, and β2-MG in the experimental group was lower than those in the control group; CCr and eGFR in the experimental group were higher than those in the control group. This study demonstrated that alprostadil may reduce the incidence of CIN in patients undergoing coronary angiogram and/or percutaneous coronary intervention.

Computed tomography pulmonary angiography and venography with a low dose of contrast medium

The authors developed a method to ensure sufficient opacification of pulmonary vasculature for separate depiction of arteries and veins in three-dimensional form with a small dose of contrast medium utilizing a test injection to determine optimal timing of computed tomography (CT) scanning. The dose was determined by a simulation based on a pharmacokinetic model. The contrast medium was administered at a rate of 5.0 mL/s for 3 s, followed by helical scanning at the timing determined by a dynamic CT scanning following the test injection. Images of 20 consecutive patients acquired with a 64-row CT scanner were evaluated. Quality of vessel depiction was assessed on the basis of the following: HU values at the main pulmonary artery (MPA) and left atrium (LA), distance between the pleural surface and the distal end of the pulmonary vessels on three-dimensional CT pulmonary arteriography and venography (3D-CTPAV), and subjective visual assessment of quality of the 3D-CTPAV images. Time to generate the 3D-CTPAV images was recorded. The mean ± standard deviation (SD) of the HU values at MPA/LA and the distances to the pleural surface for pulmonary arteries/veins were 448.0 ± 123.1/277.3 ± 60.85 HU and 9.21 ± 3.60/10.7 ± 5.45 mm, respectively. The image quality was visually rated as excellent for all of the patients. The mean time ± SD to generate 3D-CTPAV images was 13.6 ± 6.7 min. In conclusion, three-dimensional images of the pulmonary vasculature can be created using 21 mL (including 6 mL for the test injection) of contrast medium.

Effect of trimetazidine on preventing contrast-induced nephropathy in diabetic patients with renal insufficiency

BACKGROUND

Our study sought to assess the effect of trimetazidine (TMZ) on preventing contrast-induced nephropathy (CIN) in diabetic patients with renal insufficiency.

MATERIALS AND METHODS

106 diabetic patients with renal insufficiency who were undergoing coronary angiography (CAG) and/or percutaneous coronary intervention (PCI) were enrolled in this study. Standard hydration was administered to both groups (the TMZ group and the control group). In the TMZ group, patients were orally administered TMZ for 48 hours before and 24 hours after CAG and/or PCI. Serum creatinine (Scr), cystatin C and the glomerular filtration rate (eGFR) were measured before as well as 24 hours, 48 hours and 72 hours after contrast media injection. The incidence of CIN and major cardiovascular events (MACE) was also evaluated in both groups.

RESULTS

Scr, cystatin C and the eGRF in the TMZ group were better than those in the control group after 24 hours (OR: 0.78, 95% CI: 0.54-0.82; OR: 0.66, 95% CI: 0.62-0.73; OR: 1.2, 95% CI: 1.02-1.53, respectively), 48 hours (OR: 0.69, 95% CI: 0.52-0.73; OR: 0.76, 95% CI: 0.69-0.84; OR: 1.5, 95% CI: 1.25-1.68, respectively) and 72 hours (OR: 0.82, 95% CI: 0.77-0.91; OR: 0.85, 95% CI: 0.71-0.92; OR: 1.67, 95% CI: 1.33-1.72, respectively). The incidence of CIN (9.26% vs 16.67%) and MACE (7.41% vs 18.51%) in the TMZ group was significantly lower than that in the control group (P < 0.05).

CONCLUSIONS

Our study suggests that TMZ could reduce the incidence of CIN and MACE in diabetic patients with renal insufficiency who are undergoing CAG and/or PCI.

Contrast media-induced nephropathy: how has Italy contributed in the past 30 years? A systematic review

Background and objective

The use of contrast media in Italy has exponentially increased in the past 3 decades. However, it is unknown whether there has been an increase in clinical research evaluating the risks associated with contrast media usage, especially regarding contrast-induced nephropathy. To fill this gap in knowledge, we performed a systematic review.

Study eligibility criteria

Meta-analyses, observational studies, and clinical trials assessing contrast media-induced nephropathy as the safety outcome, in which at least one author was affiliated with an Italian university/health care structure, were eligble.

Data sources

Ovid MEDLINE, Ovid Embase, Cochrane Methodology Register, and Web of Science were screened.

Participants

Men and women exposed to contrast media.

Results

In total, 60 original articles were retrieved with an incremental trend between 1990 and 2017. Cohort studies were the most common study design represented. In total, 45 of 60 (75.0%) studies were monocenter studies and 41 of 60 (68.3%) received no funding. In all, 91.7% of studies disclosed no conflicts of interest and 81.7% had no external collaboration. Most of the studies provided a level of evidence of III-2 (32/60; 53.3%) and II (23/60; 38.3%). In total, 50 of 60 studies (83.3%) were published in a scientific journal ranked in the first quartile of their subject area.

Conclusion

There was an increased number of studies evaluating contrast-induced nephropathy in Italy during the last three decades. These studies covered procedures to prevent contrast-induced nephropathy or aimed to identify risk factors, biomarkers, and scores, and their related prognosis.

Time- and dose-dependent cytotoxicities of ioxitalamate and indigocarmine in human nucleus pulposus cells

BACKGROUND CONTEXT

Ioxitalamate (Telebrix 300) is an ionic iodinated contrast medium commonly used for discography or percutaneous endoscopic lumbar discectomy (PELD), though it has side effects such as anaphylactic shock and renal toxicity. Indigocarmine is an organic compound dye with a distinctive blue color that is commonly used during PELD to stain the acidic, degenerated nucleus pulposus (NP). Although ioxitalamate and indigocarmine are widely used in spinal surgery, there have been no reports on their effects on NP cells. We studied the toxicities of both ioxitalamate and indigocarmine to NP cells.

PURPOSE

To determine the toxicities of both ioxitalamate and indigocarmine to NP cells in vitro.

STUDY DESIGN

In vitro, controlled study of the toxicities of both ioxitalamate and indigocarmine to human NP cells.

METHODS

Nucleus pulposus cells were obtained via discectomy from lumbar disc patients and isolated. Nucleus pulposus cells were cultured in three-dimensional (3D) alginate beads with 0.001, 0.1, 10, and 100 mg/mL ioxitalamate, 0.00001, 0.001, 0.1, and 10 mg/mL indigocarmine, or a mixture of both for 1, 2, or 3 days. The living cells were analyzed with trypan blue staining. Fluorescence Activated Cell Sorting analysis using Annexin V and propidium iodide and 3D alginate bead immunostaining was performed to identify live, apoptotic, and necrotic cells.

RESULTS

Ioxitalamate, indigocarmine, and their combination induced statistically significant NP cell injury that was both time- and dose dependent (p<.05). Also, at the same concentration, ioxitalamate was more cytotoxic than was indigocarmine or the combination (p<.05). All three treatments also showed dose-dependent cytotoxicity according to flow cytometry and immunostaining.

CONCLUSIONS

Ioxitalamate and indigocarmine are toxic to human NP cells in vitro in a time- and dose-dependent manner. We assume that ioxitalamate and indigocarmine may have similar effects in patients undergoing discography and PELD. Thus, we suggest that ioxitalamate and indigocarmine should be used carefully at low concentrations.

Coronary computed tomography angiography using ultra-low-dose contrast media: radiation dose and image quality

To analyze the invasiveness and image quality of coronary CT angiography (CCTA) with 80 kV. We enrolled 181 patients with low body weight and low calcium level. Of these, 154 patients were randomly assigned to 1 of 3 groups: 280 HU/80 kV (n = 51); 350 HU/80 kV (n = 51); or 350 HU/120 kV (n = 52). The amount of contrast media (CM) was decided with a CT number-controlling system. Twenty-seven patients were excluded because of an invalid time density curve by timing bolus. The predicted amount of CM, volume CT dose index, dose-length product, effective dose, image noise, and 5-point image quality were measured. The amounts of CM for the 80 kV/280 HU, 80 kV/350 HU, and 120 kV/350 HU groups were 10 ± 4 mL, 15 ± 7 mL, and 30 ± 6 mL, respectively. Although image noise was greater at 80 than 120 kV, there was no significant difference in image quality between 80 kV/350 HU and 120 kV/350 HU (p = 0.390). There was no significant difference in image quality between 80 kV/280 HU and 80 kV/350 HU (4.4 ± 0.7 vs. 4.7 ± 0.4, p = 0.056). The amount of CM and effective dose was lower for 80 kV CCTA than for 120 kV CCTA. CCTA at 80 kV/280 HU may decrease the amount of CM and radiation dose necessary while maintaining image quality.

Controlling intracoronary CT number for coronary CT angiography

BACKGROUND

Controlling intracoronary computed tomography (CT) number for coronary CT angiography (CCTA) has been difficult.

OBJECTIVE

The study assessed whether intracoronary CT number of CCTA could be estimated.

METHODS

One hundred twenty six patients were randomly assigned to either CCTA with 30 mL of contrast media (CM) following 5 mL of CM at timing bolus or CCTA with 50 mL of CM following 10 mL of CM at timing bolus. The relationships between intracoronary CT number and patients' characteristics and peak time and peak CT number at timing bolus in patients who showed valid time-density curve were analyzed in both groups. Then, the multiple regression equation best described was made. The prediction system was validated by 112 patients randomly targeted between 250 HU and 430 HU of CT number.

RESULTS

In group 5/30, intracoronary CT number was positively correlated with peak CT number at timing bolus (correlation coefficient, 1.42, p<0.001), negatively correlated with body surface area (-109.19, p<0.001) and peak time (-6.93, p<0.001). Whereas, intracoronary CT number was positively correlated with only peak CT number at timing bolus (1.33, p<0.001) in group 10/50. Then, CT number-controlling system using the simple equation best described CT number was established for CCTA following 5 mL of CM at timing bolus. Of 112 patients, there was good correlation between target CT number and measured CT number (r=0.85, p<0.0001) in 96 patients (85.7%), having valid time-density curve at timing bolus.

CONCLUSIONS

Controlling CT number may be enabled by CT number-controlling system following 5 mL of CM at timing bolus.

Aged rats are susceptible to nephrotoxicity induced by iodinated contrast media

OBJECTIVE

The objective of this study is to evaluate the effect and mechanism of aging on iodinated-contrast-media-induced nephropathy in male rats.

METHODS

Twenty-four healthy male rats were initially divided into 12-month-old and 24-month-old age groups (adult and older age groups, respectively; n = 12/group); subsequently, each age group was randomly divided into saline control (NS) and contrast media (CM) groups (n = 6/group). CM (76% diatrizoate, 10 mL/kg b.w.) was given through the caudal vein. Urinary creatinine (Ucr) and serum creatinine (Scr) were detected by an automatic biochemical analyzer. The activities of renal malondialdehyde (MDA), superoxide dismutase (SOD), angiotensin-converting enzyme (ACE), angiotensin II (Ang II), and reduced form of nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) were determined by spectrophotometric assays with commercially available kits according to the manufacturers' protocols. Renal histological changes were observed by hematoxylin and eosin staining and scored semiquantitatively.

RESULTS

In diatrizoate-injected aged rats, Scr, the activities of ACE, Ang II, MDA, and NADPH oxidase in renal tissues were significantly increased (p < 0.01). The histologic scores were higher in the aged animals with CM treatment than those of control or adult rats (p < 0.01). There was an increasing trend but no significant statistical difference in renal ACE, Ang II, MDA, and NADPH oxidase or histologic scores in adult CM-injected rats compared with control animals (p > 0.05).

CONCLUSIONS

Older age is an aggravating factor of iodinated-contrast-media-induced nephropathy in male rats. Oxidative stress and the renin-angiotensin system (RAS) may play an important role in nephrotoxicity induced by iodinated contrast media, especially in aged male rats.

What is the cell hydration status of healthy children in the USA? Preliminary data on urine osmolality and water intake

OBJECTIVE

Hyperosmotic stress on cells limits many aspects of cell function, metabolism and health. International data suggest that schoolchildren may be at risk of hyperosmotic stress on cells because of suboptimal water intake. The present study explored the cell hydration status of two samples of children in the USA.

DESIGN

Cross-sectional study describing the urine osmolality (an index of hyperosmotic cell shrinkage) and water intake of convenience samples from Los Angeles (LA) and New York City (NYC).

SETTING

Each participant collected a urine sample at an outpatient clinic on the way to school on a weekday morning in spring 2009. Each was instructed to wake, eat, drink and do as usual before school, and complete a dietary record form describing the type and amounts of all foods and beverages consumed after waking, before giving the sample.

SUBJECTS

The children (9-11 years) in LA (n 337) and NYC (n 211) considered themselves healthy enough to go to school on the day they gave the urine sample.

RESULTS

Elevated urine osmolality (>800 mmol/kg) was observed in 63 % and 66 % of participants in LA and NYC, respectively. In multivariable-adjusted logistic regression models, elevated urine osmolality was associated with not reporting intake of drinking water in the morning (LA: OR = 2·1, 95 % CI 1·2, 3·5; NYC: OR = 1·8, 95 % CI 1·0, 3·5). Although over 90 % of both samples had breakfast before giving the urine sample, 75 % did not drink water.

CONCLUSIONS

Research is warranted to confirm these results and pursue their potential health implications.

Current cardiac imaging techniques for detection of left ventricular mass

Estimation of left ventricular (LV) mass has both prognostic and therapeutic value independent of traditional risk factors. Unfortunately, LV mass evaluation has been underestimated in clinical practice. Assessment of LV mass can be performed by a number of imaging modalities. Despite inherent limitations, conventional echocardiography has fundamentally been established as most widely used diagnostic tool. 3-dimensional echocardiography (3DE) is now feasible, fast and accurate for LV mass evaluation. 3DE is also superior to conventional echocardiography in terms of LV mass assessment, especially in patients with abnormal LV geometry. Cardiovascular magnetic resonance (CMR) and cardiovascular computed tomography (CCT) are currently performed for LV mass assessment and also do not depend on cardiac geometry and display 3-dimensional data, as well. Therefore, CMR is being increasingly employed and is at the present standard of reference in the clinical setting. Although each method demonstrates advantages over another, there are also disadvantages to receive attention. Diagnostic accuracy of methods will also be increased with the introduction of more advanced systems. It is also likely that in the coming years new and more accurate diagnostic tests will become available. In particular, CMR and CCT have been intersecting hot topic between cardiology and radiology clinics. Thus, good communication and collaboration between two specialties is required for selection of an appropriate test.