Long term impact of transjugular intrahepatic portosystemic shunt (TIPS) creation on hepatic morphology

PURPOSE

The purpose of this study was to evaluate long-term morphologic changes occurring in the liver after TIPS creation with correlation with hepatic function to gain insight on the physiologic impact of TIPS on the liver.

METHODS

This retrospective study included patients who underwent TIPS creation between 2005 and 2022 and had contrasted CT or MRI studies prior to and between 1 and 2 years post procedure. Strict exclusion criteria were applied to avoid confounding. Parenchymal volume and vessel measurements were assessed on the pre- and post-TIPS CT or MRI and MELD scores calculated.

RESULTS

Of 580 patients undergoing TIPS creation, 65 patients (mean age, 55 years; 36 males) had pre-TIPS and post-TIPS imaging meeting inclusion criteria at median 16.5 months. After TIPS, the mean MELD score increased (12.9 to 15.4; p = 0.008) and total liver volume decreased (1730 to 1432 mL; p < 0.001). However, the magnitude of volume change did not correlate with MELD change. Neither portosystemic gradient nor TIPS laterality correlated with total or lobar hepatic volume changes or MELD changes. The main portal vein diameter increased (15.0 to 18.7 mm; p < 0.001). Thrombosis of the hepatic vein used for TIPS creation resulted in a mean increase in MELD of +4.1 compared to -2.1 in patients who had a patent and normal hepatic vein (p = 0.007).

CONCLUSIONS

Given lack of correlation between portosystemic gradient, hepatic atrophy, hepatic function, and TIPS laterality, the alterations in portal flow dynamics after TIPS may not be impactful to hepatic function. However, hepatic vein patency after TIPS correlated with improved hepatic function.

Computed Tomography Volumetry of Bone Cement: Retrospective Blinded Validation of Commercially Available Semi-automated Edge Detection Software

OBJECTIVE

Cement volumes are increasingly linked to orthopedic oncology and neurosurgical outcomes (construct durability, adjacent fracture), but manual cement volumetry remains time prohibitive. The authors aim to report performance of PACS-integrated volumetric software specifically for barium-enhanced polymethylmethacrylate cement.

METHODS

Institutional review board-approved single-institution retrospective review of patients from 2019-2022 undergoing kyphoplasty for pathological compression fractures with a quantitative cement infuser providing true cement volume. An operator blinded to true cement volumes retrospectively performed software-assisted volumetry on follow-up computed tomography scans.

RESULTS

Included were 91 kyphoplasty levels in 56 patients: mean age, 62 years (range, 34-85 years), 73% female. True cement volume (available for 44 of 66 procedures) was mean 4.5 mL per level (range, 1.2-15.6 mL). Measured cement volume (available for all procedures) yielded a mean of 6.1 mL per level (range, 1.5-27.9 mL). For the 57 levels (39 patients) where both true and measured cement volumes were available, linear regression intercept and slope were 1.46 (95% CI = 0.97-1.95, P < 0.001) and 0.52 (CI = 0.47-0.57, P < 0.001), respectively, suggesting measured volume averaged 1.46 mL greater than true volume, with each additional milliliter of measured volume corresponding to approximately 0.52 mL of true volume. There was no significant difference in the relationship between estimated and actual cement volume in thoracic levels (intercept = -0.24, CI = -1.13 to 0.66, P = 0.61; slope = 0.03, CI = -0.14 to 0.19, P = 0.73) compared with lumbar levels. The goodness-of-fit of the regression model was strong (R2 = 0.81). Discrepancies ranged from 90% underestimation to 52% overestimation; average, 17% overestimation.

CONCLUSIONS

Semi-automated volumetry maintained a strong correlation with true volumes across the thoracic and lumbar curvatures, overestimating cement volume by a mean of 17% or 1.46 mL.

Fatty kidney: A possible future for chronic kidney disease research

BACKGROUND

Metabolic syndrome is a growing twenty-first century pandemic associated with multiple clinical comorbidities ranging from cardiovascular diseases, non-alcoholic fatty liver disease and polycystic ovary syndrome to kidney dysfunction. A novel area of research investigates the concept of fatty kidney in the pathogenesis of chronic kidney disease, especially in patients with diabetes mellitus or metabolic syndrome.

AIM

To review the most updated literature on fatty kidney and provide future research, diagnostic and therapeutic perspectives on a disease increasingly affecting the contemporary world.

MATERIALS AND METHOD

We performed an extensive literature search through three databases including Embase (Elsevier) and the Cochrane Central Register of Controlled Trials (Wiley) and PubMed/Medline Web of Science in November 2021 by using the following terms and their combinations: 'fatty kidney', 'ectopic fat', 'chronic kidney disease', 'cardiovascular event', 'cardio-metabolic risk', 'albuminuria' and 'metabolic syndrome'. Each study has been individually assessed by the authors.

RESULTS

Oxidative stress and inflammation, Klotho deficiency, endoplasmic reticulum stress, mitochondrial dysfunction and disruption of cellular energy balance appear to be the main pathophysiological mechanisms leading to tissue damage following fat accumulation. Despite the lack of large-scale comprehensive studies in this novel field of research, current clinical trials demonstrate fatty kidney as an independent risk factor for the development of chronic kidney disease and cardiovascular events.

CONCLUSION

The requirement for future studies investigating the pathophysiology, clinical outcomes and therapeutics of fatty kidney is clear.

Future of kidney imaging: Functional magnetic resonance imaging and kidney disease progression

INTRODUCTION

Chronic kidney disease (CKD) which is a common cause of death has an increasing trend, but there is no established approach for predicting CKD progression yet. Functional magnetic resonance imaging (fMRI) studies such as blood oxygenation level-dependent MRI (BOLD-MRI), diffusion-weighted MRI (DWI-MRI), diffusion-tensor MRI (DTI-MRI) and arterial spin labelling MRI (ASL-MRI) are rising methods for the assessment of kidney functions in native and transplanted kidneys as well as the estimation of CKD progression.

METHODS

Systematic literature review was performed through the Embase (Elsevier), Cochrane Central Register of Controlled Trials (Wiley), PubMed/Medline and Web of Science databases, and studies investigating the role of fMRI methods assessing kidney functions in native and transplanted kidneys, as well as the value of fMRI methods to predict CKD progression, were included. Working mechanisms, advantages and limitations of the fMRI modalities were reviewed, and three studies investigating the role of fMRI studies in kidney functions were analysed.

RESULTS AND CONCLUSION

BOLD-MRI signal was found to be inversely correlated with annual eGFR change, and DWI/ADC (apparent diffusion coefficient map) values were shown to be correlated with annual eGFR decline. fMRI methods which are currently used for other systems can be utilized to provide more detailed information about kidney functions, and doctors should be ready to interpret kidney MRIs.

Safety Profile of Particle Embolization for Treatment of Acute Lower Gastrointestinal Bleeding

PURPOSE

To assess ischemic adverse events following particle embolization when used as a second-line embolic to coil embolization for treatment of acute lower gastrointestinal bleeding(LGIB).

MATERIALS AND METHODS

This single-institution retrospective study examined 154 procedures where embolization was attempted for LGIB. In 122 patients (64 males, mean age 69.9 years), embolization was successfully performed using microcoils in 73 procedures, particles in 34 procedures, and both microcoils and particles in 27 procedures. Particles were used as second-line only when coil embolization was infeasible or inadequate. Technical success was defined as angiographic cessation of active extravasation after embolization. Clinical success was defined as absence of recurrent bleeding within 30 days of embolization.

RESULTS

Technical success for embolization of LGIB was achieved in 87.0% of cases (134/154), and clinical success was 76.1%(102/134) among technically successful cases. Clinical success was 82.2%(60/73) for coils alone and 68.9%(42/61) for particles +/- coils. Severe adverse events involving embolization-induced bowel ischemia occurred in 3 of 56 patients who underwent particle embolization +/- coils (5.3%) versus zero out of 66 patients when coils alone were used (P=0.09). In patients who had colonoscopy or bowel resection within 2 weeks of embolization, ischemic findings attributable to the embolization were found in 3 of 15 who underwent embolization with coils alone, versus 8 of 18 who underwent embolization with particles +/- coils (p=0.27).

CONCLUSION

Particle embolization for treatment of LGIB as second line to coil embolization was associated with a 68.9% clinical success rate and a 5.3% rate of ischemia-related adverse events.

Determinants of Pancreatic Steatosis: A Retrospective Observational Study

BACKGROUND Metabolic syndrome affects 35% of the adult population in developed countries associated with non-alcoholic steatohepatitis, insulin resistance, and cardiovascular events. Fatty infiltration of the pancreas, or pancreatic steatosis, is a risk factor for acute pancreatitis, pancreatic malignancies, and diabetes mellitus, yet its relationship with metabolic syndrome is not well defined. METHODS We performed a single-centered retrospective observational study of 322 healthy subjects (subjects volunteering to be kidney transplant donors, mean age=46.3±13.5, 163 men and 159 women) in the last 2 years (July 2018-February 2020) from our institution. Pancreatic steatosis and hepatosteatosis were confirmed by computed tomography. RESULTS Pancreatic steatosis was present in 26.3% (85/322) of the subjects, and this finding correlated with age, body mass index (BMI), male sex, a family history of diabetes, creatinine, cystatin C, uric acid, low-density lipoprotein (LDL) cholesterol, triglycerides, glycemia, hemoglobin, transverse body diameter, and subcutaneous fat thickness levels by univariable logistic regression. On multiple linear regression only age (95% CI 1.01, 1.06), BMI (95% CI 1.01, 1.19), male sex (95% CI 1.49-5.99), uric acid (95% CI 1.01, 1.76), and subcutaneous fat thickness levels (95% CI 1.21-2.36) remained independently associated with pancreatic steatosis. CONCLUSION Pancreatic steatosis is common and associated with obesity, elevated serum uric acid, subcutaneous fat thickness, and male sex. Future studies are needed to evaluate if there are specific clinical consequences to the presence of pancreatic steatosis.

A primer on metabolic memory: why existing diabesity treatments fail

Despite massive government and private sector investments into prevention of cardiovascular disease, diabetes mellitus and obesity, efforts have largely failed, and the burden of cost remains in the treatment of downstream morbidity and mortality, with overall stagnating outcomes. A new paradigm shift in the approach to these patients may explain why existing treatment strategies fail, and offer new treatment targets. This review aims to provide a clinician-centred primer on metabolic memory, defined as the sum of irreversible genetic, epigenetic, cellular and tissue-level alterations that occur with long-time exposure to metabolic derangements.

Evaluation of repeat distal transradial access in the anatomic snuffbox

PURPOSE

There is increasing interest in the distal radial artery in the anatomic snuffbox as an alternative arterial access point, but the durability of the distal radial artery to support repetitive accesses over multiple procedures is not well established. The purpose of this study was therefore to evaluate success rates for repeated left-sided distal transradial access (ldTRA) in the anatomic snuffbox.

METHODS

In this single institution retrospective study, all patients undergoing radioembolization treatments from January 1st, 2019 to May 1st, 2020 were prospectively evaluated for ldTRA. ldTRA was performed by 15 different operators. Exclusion criteria were a left radiocephalic hemodialysis fistula, inability to properly position the arm, Barbeau D waveform, or failed prior ldTRA due to tortuosity. Barbeau patterns, arterial sizes, and success rates at the first, second, and third ldTRA were compared.

RESULTS

Fifty patients were evaluated for ldTRA and 44, 39, and 10 underwent one, two, and three ldTRA attempts for a total of 93 procedures. There was no significant change in Barbeau patterns between the first and second (p = 0.13) or first and third (p = 1.0) ldTRA. There was no significant change in artery size between the first (mean, 2.3 mm; range, 1.5-3.4 mm) and second (mean, 2.3 mm; range, 1.6-3.3 mm) (p = 0.59) and first and third (mean, 2.4 mm; range, 1.9-3.3) (p = 0.45) ldTRA. The success rate was not significantly different between the first (93%, 41/44, 95% CI 81%-99%), second (95%, 37/39, 95% CI 83%-99%), and third (100%, 10/10, 95% CI 69%-100%) procedure (p = 1.0). The asymptomatic occlusion rate was 4.1% (2/49, 95% CI 0%-14%), and subsequent ldTRA was successfully completed in both patients with occlusions. There were no hemorrhagic or ischemic complications.

CONCLUSION

Success rates are indistinguishable among first, second, and third time ldTRA suggesting that this is a durable access point.

Intravascular Ultrasound-Guided Transvenous Biopsy of Abdominal and Pelvic Targets Difficult to Access by Percutaneous Needle Biopsy: Technique and Initial Clinical Experience

PURPOSE

To report initial clinical experience with intravascular ultrasound (US)-guided transvenous biopsy (TVB) for perivascular target lesions in the abdomen and pelvis using side-viewing phased-array intracardiac echocardiography catheters.

MATERIALS AND METHODS

In this single-institution, retrospective study, 48 patients underwent 50 intravascular US-guided TVB procedures for targets close to the inferior vena cava or iliac veins deemed difficult to access by conventional percutaneous needle biopsy (PNB). In all procedures, side-viewing phased-array intracardiac echocardiography intravascular US catheters and transjugular liver biopsy sets were inserted through separate jugular or femoral vein access sheaths, and 18-gauge core needle biopsy specimens were obtained under real-time intravascular US guidance. Diagnostic yield, diagnostic accuracy, and complications were analyzed.

RESULTS

Intravascular US-guided TVB was diagnostic of malignancy in 40 of 50 procedures for a diagnostic yield of 80%. There were 5 procedures in which biopsy was correctly negative for malignancy, with a per-procedure diagnostic accuracy of 90% (45/50). Among the 5 false negatives, 2 patients underwent repeat intravascular US-guided TVB, which was diagnostic of malignancy for a per-patient diagnostic accuracy of 94% (45/48). There were 1 (2%) mild, 2 (4%) moderate, and 1 (2%) severe adverse events, with 1 moderate severity adverse event (venous thrombosis) directly attributable to the intravascular US-guided TVB technique.

CONCLUSIONS

Intravascular US-guided TVB performed on difficult-to-approach perivascular targets in the abdomen and pelvis resulted in a high diagnostic accuracy, similar to accepted thresholds for PNB. Complication rates may be slightly higher but should be weighed relative to the risks of difficult PNB, surgical biopsy, or clinical management without biopsy.

Proton pump inhibitor use is associated with increased rates of post-TIPS hepatic encephalopathy: Replication in an independent patient cohort

PURPOSE

Proton pump inhibitor (PPI) use is a potential risk factor for hepatic encephalopathy (HE), but few studies have examined the effect on post-TIPS HE. The purpose of this study was to determine whether PPIs are associated with increased rates of post-TIPS HE in an independent patient cohort.

MATERIALS AND METHODS

This single-institution retrospective study analyzed 86 patients (54 male, mean age 58.2) following TIPS from 1/1/2017 to 12/31/2019. Dates of PPI usage and episodes of new or worsening HE were recorded. Poisson regression with generalized estimating equations was used to test for association between PPI use and post-TIPS HE and to test for dose dependence. Post-TIPS HE was also analyzed using the Andersen-Gill survival model for recurrent events.

RESULTS

There were 1.88 episodes of new or worsening post-TIPS HE per person-year among 35 patients on uninterrupted PPIs therapy, 1.95 on PPIs and 0.94 off PPIs among 35 patients on intermittent therapy, and 0.47 among 16 patients never on PPIs. PPI use was significantly associated with post-TIPS HE in both univariable (incidence rate ratio (IRR) = 2.62; CI = 1.41-4.84; p = 0.002) and multivariable (IRR = 2.31; CI = 1.37-3.89; p = 0.002) regression. Analysis of only those patients on PPIs showed increased rates of HE with higher doses (IRR = 1.17 per 10 mg omeprazole equivalent; CI = 1.04-1.33; p = 0.011). Recurrent events survival analysis supported the association between PPI use and HE in univariable (hazard ratio (HR) = 2.17; CI = 1.19-3.95; p = 0.011) and multivariable (HR = 1.87; CI = 1.12-3.13; p = 0.017) analysis.

CONCLUSION

In an independent patient cohort PPI use was associated with increased rates of new or worsening post-TIPS HE.

Polymer-assisted intratumoral delivery of ethanol: Preclinical investigation of safety and efficacy in a murine breast cancer model

Focal tumor ablation with ethanol could provide benefits in low-resource settings because of its low overall cost, minimal imaging technology requirements, and acceptable clinical outcomes. Unfortunately, ethanol ablation is not commonly utilized because of a lack of predictability of the ablation zone, caused by inefficient retention of ethanol at the injection site. To create a predictable zone of ablation, we have developed a polymer-assisted ablation method using ethyl cellulose (EC) mixed with ethanol. EC is ethanol-soluble and water-insoluble, allowing for EC-ethanol to be injected as a liquid and precipitate into a solid, occluding the leakage of ethanol upon contact with tissue. The aims of this study were to compare the 1) safety, 2) release kinetics, 3) spatial distribution, 4) necrotic volume, and 5) overall survival of EC-ethanol to conventional ethanol ablation in a murine breast tumor model. Non-target tissue damage was monitored through localized adverse events recording, ethanol release kinetics with Raman spectroscopy, injectate distribution with in vivo imaging, target-tissue necrosis with NADH-diaphorase staining, and overall survival by proxy of tumor growth. EC-ethanol exhibited decreased localized adverse events, a slowing of the release rate of ethanol, more compact injection zones, 5-fold increase in target-tissue necrosis, and longer overall survival rates compared to the same volume of pure ethanol. A single 150 μL dose of 6% EC-ethanol achieved a similar survival probability rates to six daily 50 μL doses of pure ethanol used to simulate a slow-release of ethanol over 6 days. Taken together, these results demonstrate that EC-ethanol is safer and more effective than ethanol alone for ablating tumors.

Serum glycated albumin predicts all-cause mortality in dialysis patients with diabetes mellitus: meta-analysis and systematic review of a predictive biomarker

BACKGROUND AND AIM

HbA1c, the traditional and current gold standard biomarker guiding diabetic management, has been scrutinized for low predictive value for patients with chronic kidney disease due to variables affecting erythrocyte number and turnover. Glycated albumin, the precursor to advanced glycation end products, reflects glycemic status over the preceding 2-3 week period and already outperforms HbA1c for glycemic monitoring. Our aim was to establish whether serum GA can be further used to predict mortality risk in dialysis patients with diabetes mellitus (DM) METHODS: We did systematic review of the literature in PubMed/Medline, Web of Science, Embase (Elsevier) and the Cochrane Central Register of Controlled Trials (Wiley) up to and including February 2020.

RESULTS

This meta-analysis included 25,932 dialysis patients across 12 studies with maximum follow-up of 11 years. Higher GA levels were associated with the risk of all-cause mortality in dialysis patients with DM (HR 1.02, 95% CI 1.01 to 1.03, P < 0.001) irrespective of the type of dialysis, whereas higher GA was not associated with cardiovascular mortality (HR 1.03, 95% CI 0.99 to 1.06, P = 0.15) and cardiovascular events (both fatal and non-fatal) (HR 1.03, 95% CI 0.97 to 1.09, P = 0.31) in dialysis patients with DM.

CONCLUSION

Serum glycated albumin predicts all-cause mortality risk in dialysis patients with DM. The endpoints of cardiovascular mortality and cardiovascular events trended similarly, but did not reach significance at the current sample size.

Percutaneous gastrojejunostomy tubes: Identification of predictors of retrograde jejunal limb migration into the stomach

PURPOSE

To identify whether technically modifiable factors during gastrojejunostomy (GJ) tube insertion are predictive of retrograde jejunal limb migration into the stomach.

MATERIALS AND METHODS

Retrospective review of our procedural database over a 5-year period revealed 988 successful primary GJ tube insertions. Medical records and imaging were reviewed for cases of retrograde jejunal limb migration. Primary analysis was performed on 74 patients with retrograde tip migration within 3 months after placement (37 males, mean age = 57). Comparison was performed on 67 control patients (34 males, mean age = 51) who had radiologically confirmed GJ tube stability for at least 6 months. Procedural fluoroscopic images were analyzed for multiple GJ tube configuration parameters. The stomach was designated into antrum, body, and fundus. Predictors of retrograde tip migration were analyzed with univariate and multivariate logistic regression analysis.

RESULTS

A total of 110 patients (11.1%) had retrograde jejunal limb migration, with 74 (7.5%) occurring within 3 months of placement. On multivariate analysis, the factors associated with a significantly lower risk of tip malposition included gastric puncture site in the antrum (OR: 0.27, 95% CI: 0.13-0.56, p < 0.001) and GJ tract angle less than 30 degrees away from the pylorus (OR: 0.35, 95% CI: 0.16-0.76, p = 0.008). No patient in either cohort had a major complication within 30 days of procedure.

CONCLUSION

To minimize the risk of retrograde tip migration, GJ tubes should be inserted into the gastric antrum with an entry tract oriented as directly towards the pylorus as possible.

Sweet dreams: therapeutic insights, targeting imaging and physiologic evidence linking sleep, melatonin and diabetic nephropathy

Melatonin is the main biochronologic molecular mediator of circadian rhythm and sleep. It is also a powerful antioxidant and has roles in other physiologic pathways. Melatonin deficiency is associated with metabolic derangements including glucose and cholesterol dysregulation, hypertension, disordered sleep and even cancer, likely due to altered immunity. Diabetic nephropathy (DN) is a key microvascular complication of both type 1 and 2 diabetes. DN is the end result of a complex combination of metabolic, haemodynamic, oxidative and inflammatory factors. Interestingly, these same factors have been linked to melatonin deficiency. This report will collate in a clinician-oriented fashion the mechanistic link between melatonin deficiency and factors contributing to DN.

Complications of metabolic acidosis and alkalinizing therapy in chronic kidney disease patients: a clinician-directed organ-specific primer

Chronic kidney disease is prevalent, affecting more than one in ten adults. In this population, metabolic acidosis is considered a key underlying pathophysiological feature, tying together bone mineral disorders, sarcopenia, insulin resistance, vascular calcification, pro-inflammatory and pro-thrombotic states. This review aims to address the paucity of literature on alkalinizing agents, a promising treatment option that has known adverse effects.

Length of Stay Predicts Risk of Early Infection for Hospitalized Patients Undergoing Central Venous Port Placement

PURPOSE

To compare early totally implantable central venous port catheter-related infection rates after inpatient vs outpatient placement and to determine whether the risk associated with inpatient placement is influenced by length of hospital stay.

MATERIALS AND METHODS

In this single-institution retrospective study, 5,301 patients (3,618 women; mean age 57 y) underwent port placement by interventional radiologists between October 2004 and January 2018. The 30-day infection rate was compared between inpatients and outpatients using survival analysis. Among inpatients, the effect of time from admission to port placement and from placement to discharge was analyzed using a survival regression tree.

RESULTS

The 30-day infection rate was 3.6% (95% confidence interval [CI] = 1.9%-6.1%) among 386 inpatients and 1.0% (95% CI = 0.7%-1.3%) among 4,915 outpatients (hazard ratio [HR] = 3.6, 95% CI = 2.0-6.6, P < .001). Inpatient placement was a significant risk factor after accounting for covariates in multivariate analysis (HR = 2.2, 95% CI = 1.0-4.7, P = .05) and controlling for demographic differences by propensity score matching (HR = 2.8, 95% CI = 1.0-7.8, P = .04). Infection rate was 11% (95% CI = 4.7%-22%) among 65 inpatients in whom time from admission to placement was ≥ 7 days, 5.1% (95% CI = 1.9%-11%) among 129 inpatients in whom admission to placement was < 7 days and time to discharge was > 3 days, and 0% (95% CI = 0%-2.1%) among 192 inpatients in whom admission to placement was < 7 days and time to discharge was ≤ 3 days (P < .001).

CONCLUSIONS

Inpatient port placement was associated with a higher risk of early infection. However, a clinical decision tree based on shorter length of stay before and after placement may identify a subset of hospitalized patients not at increased risk for infection.

Effect of Uric Acid-Lowering Agents on Cardiovascular Outcome in Patients With Heart Failure: A Systematic Review and Meta-Analysis of Clinical Studies

Several trials have been completed in patients with heart failure (HF) treated with uric acid (UA)-lowering agents with inconsistent results. We aimed to investigate whether lowering UA would have an effect on mortality and cardiovascular (CV) events in patients with HF in a systematic review and meta-analysis. The primary outcome measures were all-cause mortality, CV mortality, CV events, and CV hospitalization in patients with HF. We included 11 studies in our final analysis. Overall, allopurinol treatment was associated with a significant increase in the risk for all-cause mortality (hazard ratio [HR]: 1.24, 95% confidence interval [CI]: 1.04-1.49, P = .02). The trial heterogeneity is high (heterogeneity χ² = 37.3, I2 = 73%, P < .001). With regard to CV mortality, allopurinol treatment was associated with a 42% increased risk of CV mortality (HR: 1.42, 95% CI: 1.11-1.81, P = .005). There was a trend toward increased CV hospitalization in the same group (HR: 1.21, 95% CI: 0.95-1.53, P = .12). Uric acid-lowering treatments increase all-cause and CV mortality but did not increase CV hospitalization significantly in this study.

The Effect of Urine pH and Urinary Uric Acid Levels on the Development of Contrast Nephropathy

BACKGROUND

Hyperuricemia may cause acute kidney injury by activating inflammatory, pro-oxidative and vasoconstrictive pathways. In addition, radiocontrast causes an acute uricosuria, potentially leading to crystal formation. We therefore aimed to investigate the effect of urine acidity and urine uric acid level on the development of contrast-induced nephropathy (CIN) in patients undergoing elective coronary angiography.

METHODS

We enrolled 175 patients who underwent elective coronary angiography. CIN was defined as a >25% increase in the serum creatinine levels relative to basal values 48-72 h after contrast use. Prior to coronary angiography and 48-72 h later, serum uric acid, urea, creatinine, bicarbonate levels, and spot uric acid to creatinine ratio (UACR) were measured.

RESULTS

Of the 175 subjects included, 29 (16.6%) developed CIN. Those who developed CIN had a higher prevalence of diabetes, higher UACR (0.60 vs. 0.44, p = 0.014), higher contrast volume, and lower serum sodium level. With univariate analysis of a logistic regression model, the risk of CIN was found to be associated with diabetes (p = 0.0016, OR = 3.8 [95% CI: 1.7-8.7]), urine UACR (p = 0.0027, OR = 9.6 [95% CI: 2.2-42.2]), serum sodium (p = 0.0079, OR = 0.8 [95% CI: 0.77-0.96]), and contrast volume (p = 0.0385, OR = 1.8 [95% CI: 1.03-3.09]). In a multiple logistic regression model with stepwise method of selection, diabetes (p = 0.0120, OR = 3.2 [95% CI: 1.3-8.1]) and UACR (p = 0.0163, OR = 6.9 [95% CI: 1.4-33.4]) were the 2 risk factors finally identified.

CONCLUSIONS

We have demonstrated that higher urine UACR is associated with the development of CIN in patients undergoing elective coronary angiography.

Antidiuretic Hormone and Serum Osmolarity Physiology and Related Outcomes: What Is Old, What Is New, and What Is Unknown?

CONTEXT

Although the physiology of sodium, water, and arginine vasopressin (AVP), also known as antidiuretic hormone, has long been known, accumulating data suggest that this system operates as a more complex network than previously thought.

EVIDENCE ACQUISITION

English-language basic science and clinical studies of AVP and osmolarity on the development of kidney and cardiovascular disease and overall outcomes.

EVIDENCE SYNTHESIS

Apart from osmoreceptors and hypovolemia, AVP secretion is modified by novel factors such as tongue acid-sensing taste receptor cells and brain median preoptic nucleus neurons. Moreover, pharyngeal, esophageal, and/or gastric sensors and gut microbiota modulate AVP secretion. Evidence is accumulating that increased osmolarity, AVP, copeptin, and dehydration are all associated with worse outcomes in chronic disease states such as chronic kidney disease (CKD), diabetes, and heart failure. On the basis of these pathophysiological relationships, an AVP receptor 2 blocker is now licensed for CKD related to polycystic kidney disease.

CONCLUSION

From a therapeutic perspective, fluid intake may be associated with increased AVP secretion if it is driven by loss of urine concentration capacity or with suppressed AVP if it is driven by voluntary fluid intake. In the current review, we summarize the literature on the relationship between elevated osmolarity, AVP, copeptin, and dehydration with renal and cardiovascular outcomes and underlying classical and novel pathophysiologic pathways. We also review recent unexpected and contrasting findings regarding AVP physiology in an attempt to explain and understand some of these relationships.

A journey from microenvironment to macroenvironment: the role of metaflammation and epigenetic changes in cardiorenal disease

Chronic non-communicable diseases have become a pandemic public problem in the 21st century, causing enormous burden on the economy, health and quality of life of societies. The role of a chronic inflammatory state in the pathogenesis of chronic disease has been more comprehensively recognized by recent findings. The new paradigm ‘metaflammation’ focuses on metabolism-induced (high fat or fructose-based diet or excessive calorie intake) chronic inflammation. There is a close correlation between the increased incidence of chronic kidney disease (CKD) and chronic heart failure with both increased inflammatory marker levels and western-type diet. In this review we describe the concept of metaflammation, its role in the development of CKD and chronic heart disease, the molecular and signalling pathways involved and the therapeutic consequences.

No Increased Mortality After TIPS Compared with Serial Large Volume Paracenteses in Patients with Higher Model for End-Stage Liver Disease Score and Refractory Ascites

PURPOSE

To compare survival after transjugular intrahepatic portosystemic shunt (TIPS) creation versus serial large volume paracenteses (LVP) in patients with refractory ascites and higher Model for End-Stage Liver Disease (MELD) scores.

MATERIALS AND METHODS

In this retrospective study, from 1/1/2013 to 10/1/2018, 478 patients (294 male; mean age 58, range 23-89) underwent serial LVP (n = 386) or TIPS (n = 92) for ascites. Propensity-matched cohorts were constructed based on age, MELD, Charlson comorbidity index, varices, and hepatic encephalopathy. Survival was analyzed using a Cox proportional hazards model in which MELD score and TIPS were treated as time-dependent covariates. An interaction term was used to assess the impact of TIPS versus serial LVP on survival as a function of increasing MELD.

RESULTS

In the overall patient sample, higher MELD score predicted worse survival after either serial LVP or TIPS [hazard ratio (HR) = 1.13; p < 0.001], but there was no significant interaction between TIPS and higher MELD score conferring worse survival (HR = 1.01; p = 0.55). In 92 propensity-matched serial LVP and 92 TIPS patients, higher MELD score predicted worse survival after either serial LVP or TIPS (HR = 1.19; p < 0.001), but there was no significant survival interaction between TIPS and higher MELD (HR = 0.97; p = 0.22). In 30 propensity-matched serial LVP patients and 30 TIPS patients with baseline MELD greater than 18, TIPS did not predict worse survival (HR = 0.97; p = 0.94).

CONCLUSION

Higher MELD predicts poorer survival after either serial LVP or TIPS, but TIPS creation is not associated with worse survival compared to serial LVP in patients with higher MELD scores LEVEL OF EVIDENCE: Level 4, case series.

Can Incidental Vascular Calcifications at Mammography be Used as a Screening Biomarker for Heart and Kidney Disease?

Mammography is a screening test with extensive international application and financial infrastructure promoting accessibility and affordability. Designed specifically to detect microcalcifications, mammography is powered to detect calcifications in vessel walls. Breast arterial calcifications (BAC) are one of the most common incidental findings documented by mammography. This review considers the literature regarding BAC in relation to cardiovascular disease (CVD) and its risk factors. The aim is to assess the possibility of using BAC as an early surrogate imaging biomarker of CVD.

Renal artery intervention utilizing carbon dioxide angiography

Carbon dioxide angiography is an established non-nephrotoxic option for imaging of the infradiaphragmatic arteries and veins. Safe performance of the technique once required a somewhat cumbersome system, however, recent innovations have simplified implementation and expanded the user base for this technique. As such, patient access has also increased. In this issue, Hameed et al. provide initial feasibility data regarding carbon dioxide angiography and renal denervation therapy. This experience may be translated into future renovascular interventions in patients with limited renal reserve.

Revisiting angioplasty for renovascular hypertension

Following contemporary trends in arterial endovascular therapy of the lower extremities, recent major trials in anti-hypertensive renovascular revascularization have focused on outcomes after primary stenting of the renal artery. Angioplasty-only therapy has not been studied in a major trial since the year 2000. As such, the current study by Saeed et al. presents an updated data set on the technique with one unique aspect: patients underwent post-procedural physiologic scintigraphy to document the effects of unilateral intervention in patients with two kidneys. Although these physiologic changes should not supersede the clinically relevant outcome of blood pressure reduction (which was also accomplished in this study albeit to a modest but statistically significant degree), the physiologic consequences of unilateral intervention are elegantly presented in this short-term follow-up study. Furthermore, while current renovascular intervention is trending towards treatment of global renal ischemia (i.e. bilateral renal artery stenosis or renal artery stenosis in a congenitally or acquired solitary functional kidney scenario), the current study provides a useful data set for reference in guiding future renovascular revascularization studies and treatment algorithms.

Brain-kidney cross-talk: Definition and emerging evidence

Cross-talk is broadly defined as endogenous homeostatic signaling between vital organs such as the heart, kidneys and brain. Kidney-brain cross-talk remains an area with excitingly few publications despite its purported clinical relevance in the management of currently undertreated conditions such as resistant hypertension. Therefore, this review aims to establish an organ-specific definition for kidney-brain cross-talk and review the available and forthcoming literature on this topic.

The role of sodium intake in nephrolithiasis: epidemiology, pathogenesis, and future directions

The prevalence of nephrolithiasis has doubled over the last decade and the incidence in females now approaches that of males. Since dietary salt is lithogenic, a purported mechanism common to both genders is excess dietary sodium intake vis-a-vis processed and fast foods. Nephrolithiasis has far-reaching societal implications such as impact on gross domestic product due to days lost from work (stone disease commonly affects working adults), population-wide carcinogenic diagnostic and interventional radiation exposure (kidney stone disease is typically imaged with computed tomographic imaging and treated under imaging guidance and follow-up), and rising healthcare costs (surgical treatment will be indicated for a number of these patients). Therefore, primary prevention of kidney stone disease via dietary intervention is a low-cost public health initiative with massive societal implications. This primer aims to establish baseline epidemiologic and pathophysiologic principles to guide clinicians in sodium-directed primary prevention of kidney stone disease.

Acute and delayed bleeding requiring embolization after image-guided liver biopsy in patients with cancer

PURPOSE

To report incidence of acute versus delayed presentations of bleeding requiring embolization after focal liver biopsy, in correlation with angiographic findings and treatment success rates. The available literature will be reviewed as well.

MATERIALS AND METHODS

Health Insurance Portability and Accountability Act-compliant institutional review board approved retrospective review of 2180 consecutive patients undergoing 2335 targeted liver biopsies at a tertiary-care cancer center. Hepatic arterial embolization episodes within 30days from biopsy were identified via radiology PACS. Electronic medical record review was performed for indication of embolization and postembolization clinical course.

RESULTS

The incidence of postbiopsy bleeding requiring embolization was 0.5% (12/2335 biopsies). In those with bleeding, 1/12 (8%) had no hepatic arterial findings at angiography. Angiographic hepatic arterial findings resolved after embolization in 11/11 patients (100% technical success). Bleeding ceased after embolization in 10/12 patients (83% clinical success). Complications were seen in 2/12 (17%) patients: cholecystitis and hepatic infarct, respectively. Delayed presentation of bleeding (defined as >24h postbiopsy) occurred in 5/12 (42%) patients; the longest latency was 12days.

CONCLUSION

The overall incidence of bleeding requiring embolization in our population was 0.5%. This complication rate compares favorably to the 0-4.2% (median: 0.29%) rate quoted in the available, heterogeneous, literature on this topic. Delayed presentation occurred in almost half of patients. Arterial embolization carries excellent technical and clinical success rates.

Percutaneous image-guided ablation of breast tumors: an overview

Percutaneous non-surgical image-guided ablation is emerging as an adjunct or alternative to surgery in the management of benign and malignant breast tumors. This review covers the current state of the literature regarding percutaneous image-guided ablation modalities, clinical factors regarding patient selection, and future directions for research.