Quantifying the calcification of abdominal aorta and major side branches with deep learning

AIM

To explore the possibility of a neural network-based method for quantifying calcifications of the abdominal aorta and its branches.

MATERIALS AND METHODS

In total, 58 computed tomography (CT) angiography volumes were selected from a dataset of 609 to represent different stages of sclerosis. The ground truth segmentations of the abdominal aorta, coeliac trunk, superior mesenteric artery, renal arteries, common iliac arteries, and their calcifications were delineated manually. Two V-Net ensemble models were trained, one for segmenting arteries of interest and another for calcifications. The branches of interest were shortened algorithmically. The volumes of calcification were then evaluated from the arteries of interest.

RESULTS

The results indicate that automatic detection is possible with a high correlation to the ground truth. The scores for the ensemble calcification model were dice score of 0.69 and volumetric similarity (VS) of 0.80 and for the arteries of interest segmentations: aorta: dice 0.96, VS 0.98; aortic branches: dice 0.74, VS 0.87; and common iliac arteries: dice 0.72, VS 0.91.

CONCLUSIONS

The presented neural network model is the first to be capable of automatically segmenting, in addition to calcification, both the aorta and its branches from contrast-enhanced CT angiography. This technology shows promise in addressing limitations inherent in earlier methods that relied solely on plain CT.

free-flow cyanoacrylate glue embolization: Histological differences in an in vivo rabbit renal artery model

PURPOSE

The purpose of this in vivo animal study was to compare the acute histological effects on the arterial vessel wall of free-flow vs. blocked-flow embolization with metacryloxysulfolane-n‑butyl cyanoacrylate (MS-NBCA) in several concentrations.

MATERIALS AND METHODS

A total of 42 rabbit renal arteries were embolized using MS-NBCA mixed with ethiodized oil. The MS-NBCA concentration was 12.5%, 25%, or 50%. All mixtures were injected under both free-flow and blocked-flow conditions. The rabbits were euthanised 30 min after arterial embolization. Arterial-lumen distension, intimal inflammation and necrosis, peri‑arterial edema, and distality of MS-NBCA penetration were assessed histologically. Multivariable regression analyses were performed using a manual backward procedure, with linear, ordinal and logistic regression to search for factors associated with these outcomes RESULTS: Marked or severe dilatation was observed in 36 out of 42 arteries (86%) and marked or transmural intimal arteritis in all 42 arteries (42/42; 100%). Lumen dilatation caused focal vessel-wall flattening, which resulted in intimal necrosis. Multifocal necrosis extending from the intima to the media occurred in 23 out of 42 kidneys (55%) and peri‑arterial edema with multifocal vascular leakage in 19 out of 42 kidneys (45%). At multivariable analysis, blocked-flow MS-NBCA injection was associated with greater severity of vessel-wall lesions, including intimal arteritis (P = 0.003) and intimal necrosis (P = 0.014), compared to free-flow injection. Blocked-flow injection was also associated with peri‑arterial edema (P = 0.008) and greater distality of MS-NBCA penetration (P = 0.001).

CONCLUSION

Blocked-flow MS-NBCA injection during renal artery embolization is significantly associated with more acute arterial-wall damage and greater distality of glue penetration compared to free-flow injection in a rabbit model. These preliminary findings may have clinical implications, as blocked-flow injection is routinely used to treat specific vascular diseases or malformations in human.

Retrospective analysis of percutaneous intervention of the renal artery in transplanted kidneys in children and adolescents at a tertiary public hospital

BACKGROUND

This study evaluated the long-term effects of percutaneous intervention in children and adolescents with transplant renal artery stenosis (TRAS).

METHODS

Twenty patients had significant stenosis (>50%) and underwent percutaneous transluminal angioplasty (PTA/stenting) (TRAS group-intervention); 14 TNS (non-significant group -control) patients did not have significant stenosis (≤50%) and were treated clinically. The combined primary endpoints were death from all causes and late graft failure. The secondary endpoints were serum creatinine (SCr), systolic blood pressure (SBP), and diastolic blood pressure (DBP).

RESULTS

No statistically significant difference was found between TRAS-Intervention(N = 20) and TNS groups-Control (N = 14) for these clinical parameters: deaths, 1 (5.0%) vs. 0 (0.0%) (p = 1.000) and graft loss, 4 (20.0%) vs. 2 (14.3%) (p = 1.000). For the secondary endpoints, after 1 month and 1 year the values of SCr, SBP, and DBP were similar between the two groups but not statistically significant.

DISCUSSION

In the TRAS group (intervention), the stent implantation was beneficial for treating refractory hypertension and reducing blood pressure (BP) in children and adolescents. Despite the outcomes being similar in the two groups, it can be inferred that the patients in the TRAS group (intervention) would have had a worse outcome without the percutaneous intervention.

CONCLUSION

TRAS treatment with stenting can be considered for children and adolescents. Because the sample in the present study comprised of only a specific population, further studies are needed for generalization.

TRIAL REGISTRATION

The trial was registered at clinictrials.gov with trial registration number NCT04225338.

Effect of Accessory Renal Arteries on Essential Hypertension and Related Mechanisms

BACKGROUND

This case-control study aimed to determine whether there were differences between patients with essential hypertension with accessory renal arteries (ARAs) and those without ARAs.

METHODS AND RESULTS

The enrolled patients with essential hypertension were divided into the ARA group (n=200) and control group without ARAs (n=238). After propensity matching, 394 patients (197 in each of the 2 groups), were included. The 24-hour BP (4.33/2.43 mm Hg) and daytime BP (4.48/2.61 mm Hg) of patients in the ARA group were significantly higher than those of the control group (P<0.05). The flow-mediated dilation was lower in the ARA group (5.98±2.70 versus 5.18±2.66; P<0.05). In correlation analysis, the horizontal plasma aldosterone concentration had the highest correlation with 24-hour, daytime, and nighttime systolic BP (r=0.263, 0.247, and 0.243, respectively; P<0.05) and diastolic BP (r=0.325, 0.298, and 0.317, respectively; P<0.05). As for multivariate regression analysis, plasma aldosterone concentration was a significant risk factor for elevated 24-hour, daytime, and nighttime systolic BP (β=0.249 [95% CI, 0.150-0.349], 0.228 [95% CI, 0.128-0.329], and 0.282 [95% CI, 0.187-0.377], respectively; P<0.05) and elevated diastolic BP (β=0.289 [95% CI, 0.192-0.385], 0.256 [95% CI, 0.158-0.353], and 0.335 [95% CI, 0.243-0.427], respectively; P<0.05). Direct renin concentration was also a risk factor for 24-hour and daytime BPs, whereas heart rate was a risk factor correlated with 24-hour, daytime, and nighttime diastolic BP (all P<0.05). For the mixed-effects model for repeated measures, the results were similar to results of the multivariate regression analysis (all P<0.05).

CONCLUSIONS

ARAs could contribute a higher BP of patients with essential hypertension and might promote the development of essential hypertension. The mechanism might be related to overactivation of the renin-angiotensin-aldosterone system and sympathetic nervous system.

Altered immune cell phenotypes within chronically ischemic human kidneys distal to occlusive renal artery disease

Renal artery stenosis (RAS) is a major cause of ischemic kidney disease, which is largely mediated by inflammation. Mapping the immune cell composition in ischemic kidneys might provide useful insight into the disease pathogenesis and uncover therapeutic targets. We used mass cytometry (CyTOF) to explore the single-cell composition in a unique data set of human kidneys nephrectomized due to chronic occlusive vascular disease (RAS, n = 3), relatively healthy donor kidneys (n = 6), and unaffected sections of kidneys with renal cell carcinoma (RCC, n = 3). Renal fibrosis and certain macrophage populations were also evaluated in renal sections. Cytobank analysis showed in RAS kidneys decreased cell populations expressing epithelial markers (CD45-/CD13+) and increased CD45+ inflammatory cells, whereas scattered tubular-progenitor-like cells (CD45-/CD133+/CD24+) increased compared with kidney donors. Macrophages switched to proinflammatory phenotypes in RAS, and the numbers of IL-10-producing dendritic cells (DC) were also lower. Compared with kidney donors, RAS kidneys had decreased overall DC populations but increased plasmacytoid DC. Furthermore, senescent active T cells (CD45+/CD28+/CD57+), aged neutrophils (CD45+/CD15+/CD24+/CD11c+), and regulatory B cells (CD45+/CD14-/CD24+/CD44+) were increased in RAS. RCC kidneys showed a distribution of cell phenotypes comparable with RAS but less pronounced, accompanied by an increase in CD34+, CD370+, CD103+, and CD11c+/CD103+ cells. Histologically, RAS kidneys showed significantly increased fibrosis and decreased CD163+/CD141+ cells. The single-cell platform CyTOF enables the detection of significant changes in renal cells, especially in subsets of immune cells in ischemic human kidneys. Endogenous pro-repair cell types in RAS warrant future study for potential immune therapy.NEW & NOTEWORTHY The single-cell platform mass cytometry (CyTOF) enables detection of significant changes in one million of renal cells, especially in subsets of immune cells in ischemic human kidneys distal to renal artery stenosis (RAS). We found that pro-repair cell types such as scattered tubular-progenitor-like cells, aged neutrophils, and regulatory B cells show a compensatory increase in RAS. Immune cell phenotype changes may reflect ongoing inflammation and impaired immune defense capability in the kidneys.

A Case of Autosomal Dominant Polycystic Kidney Disease With Resolution of Massive Pericardial Effusion After Renal Transcatheter Artery Embolization

A 68-year-old woman being treated with hemodialysis for autosomal dominant polycystic kidney disease was admitted for progressive dyspnea over 6 months. On chest radiography, her cardiothoracic ratio had increased from 52.2% 6 months prior, to 71%, and echocardiography revealed diffuse pericardial effusion and right ventricular diastolic insufficiency. A resultant pericardial tamponade was thought to be the cause of the patient's dyspnea, and therefore a pericardiocentesis was performed, with a total of 2,000mL of fluid removed. However, 21 days later the same amount of pericardial fluid had reaccumulated. The second pericardiocentesis was performed, followed by transcatheter renal artery embolization (TAE). The kidneys, which were hard on palpation before TAE, softened immediately after TAE. After resolution of the pericardial effusion was confirmed, the patient was discharged after 24 days in hospital. Twelve months later, the patient was asymptomatic, the cardiothoracic ratio decreased to 48% on chest radiography and computed tomography revealed no reaccumulation of pericardial effusion. This case illustrates a potential relationship between enlarged kidneys in autosomal dominant polycystic kidney disease and pericardial effusion.

Role of the CCL20/CCR6 axis in tubular epithelial cell injury: Kidney-specific translational insights from acute kidney injury to chronic kidney disease

This study investigated the role of the axis involving chemokine receptor 6 (CCR6) and its ligand chemokine (C-C motif) ligand 20 (CCL20) in acute kidney disease (AKD) using an ischemia-reperfusion injury (IRI) model. The model was established by clamping the unilateral renal artery pedicle of C57BL/6 mice for 30 min, followed by evaluation of CCL20/CCR6 expression at 4 weeks post-IRI. In vitro studies were conducted to examine the effects of hypoxia and H2 O2 -induced oxidative stress on CCL20/CCR6 expression in kidney tissues of patients with AKD and chronic kidney disease (CKD). Tubular epithelial cell apoptosis was more severe in C57BL/6 mice than in CCL20 antibody-treated mice, and CCR6, NGAL mRNA, and IL-8 levels were higher under hypoxic conditions. CCL20 blockade ameliorated apoptotic damage in a dose-dependent manner under hypoxia and reactive oxygen species injury. CCR6 expression in IRI mice indicated that the disease severity was similar to that in patients with the AKD phenotype. Morphometry of CCL20/CCR6 expression revealed a higher likelihood of CCR6+ cell presence in CKD stage 3 patients than in stage 1-2 patients. Kidney tissues of patients with CKD frequently contained CCL20+ cells, which were positively correlated with interstitial inflammation. CCL20/CCR6 levels were increased in fibrotic kidneys at 4 and 8 weeks after 5/6 nephrectomy. These findings suggest that modulating the CCL20/CCR6 pathway is a potential therapeutic strategy for managing the progression of AKD to CKD.

Assessment of Angiography-Based Renal Quantitative Flow Ratio Measurement in Patients with Atherosclerotic Renal Artery Stenosis

Background

Quantitative flow ratio (QFR) is an angiography-based fractional flow reserve measurement without pressure wire or induction of hyperemia. A recent innovation that uses combined geometrical data and hemodynamic boundary conditions to measure QFR from a single angiographic view has shown the potential to measure QFR of the renal artery-renal QFR (rQFR).

Objective

The aim of this pilot study was to assess the feasibility of rQFR measurement and the contribution of rQFR in selecting patients with atherosclerotic renal artery stenosis (ARAS) undergoing revascularization.

Methods

This retrospective trial enrolled patients who had ARAS (50-90%) and hypertension. The enrolled patients were treated by optimal antihypertensive medication or revascularization, respectively, and the therapeutic strategies were based on rFFR measurement and/or clinical feature.

Results

A total of 55 patients underwent rQFR measurement. Among the enrolled patients, 18 underwent optimal antihypertensive medication and 37 underwent revascularization, 19 patients in whom rQFR and rFFR were both assessed. During the 180-day follow-up, 25 patients saw an improvement in their blood pressure among the 37 patients that underwent revascularization. ROC analysis revealed that rQFR had a high diagnostic accuracy for predicting blood pressure improvement (AUCrQFR = 0.932, 95% CI 0.798-0.998). The ideal cut-off value of rQFR for predicting blood pressure improvement after revascularization is ≤0.72 (sensitivity: 72.00%, specificity: 100%). The paired t test and Bland-Altman analyses demonstrated good agreement between rQFR and rFFR (t = 1.887, 95% CI -0.021 to 0.001, 95% limits of agreement: -0.035 to 0.055, p = 0.075). The Spearman correlation test reveals that there was a significant positive correlation between rQFR and rFFR (r = 0.952, 95% CI 0.874 to 0.982, p < 0.001).

Conclusion

The rQFR has the potential to enhance the ability of angiography to detect functionally significant renal artery stenosis during angiography and to produce results that are comparable to invasive hemodynamic assessment.

Spontaneous renal tumour regression following an aortic dissection

Spontaneous tumour regression is a rare but well-documented phenomenon, especially for renal cell carcinomas. We describe the case of a 60-year-old male who presented with chest pain and shortness of breath. He was diagnosed with a large type A aortic dissection and an incidental right renal mass, highly suspicious of a renal cell carcinoma. Following repair of the dissection, subsequent imaging showed that the renal mass had largely resolved. Spontaneous tumour regression is commonly thought to occur through immunological mechanisms. A vascular cause of tumour regression through infarction is postulated in this case. Although angioembolisation is a well-recognised management option in the context of palliative treatment of symptomatic renal tumours, this case suggests an extended role for angioembolisation in the treatment of small renal masses.

Advanced optical imaging reveals preferred spatial orientation of podocyte processes along the axis of glomerular capillaries

Mammalian kidneys filter enormous volumes of water and small solutes, a filtration driven by the hydrostatic pressure in glomerular capillaries, which is considerably higher than in most other tissues. Interdigitating cellular processes of podocytes form the slits for fluid filtration connected by the membrane-like slit diaphragm cell junction containing a mechanosensitive ion channel complex and allow filtration while counteracting hydrostatic pressure. Several previous publications speculated that podocyte processes may display a preferable orientation on glomerular capillaries instead of a random distribution. However, for decades, the controversy over spatially oriented filtration slits could not be resolved due to technical limitations of imaging technologies. Here, we used advanced high-resolution, three-dimensional microscopy with high data throughput to assess spatial orientation of podocyte processes and filtration slits quantitatively. Filtration-slit-generating secondary processes preferentially align along the capillaries' longitudinal axis while primary processes are preferably perpendicular to the longitudinal direction. This preferential orientation required maturation in development of the mice but was lost in mice with kidney disease due to treatment with nephrotoxic serum or with underlying heterologous mutations in the podocyte foot process protein podocin. Thus, the observation that podocytes maintain a preferred spatial orientation of their processes on glomerular capillaries goes well in line with the role of podocyte foot processes as mechanical buttresses to counteract mechanical forces resulting from pressurized capillaries. Future studies are needed to establish how podocytes establish and maintain their orientation and why orientation is lost under pathological conditions.

Abdominal aortic branches of red-rumped agouti (Dasyprocta leporina Linnaeus, 1758)

Understanding the cardiovascular system is fundamental in diagnosing pathologies and interpreting exams, such as contrast radiographs. In this context, the present study describes the collateral abdominal aorta artery branches of red-rumped agouti. Ten red-rumped agoutis, six males and four females, were assessed. The vascular system was perfused with Neoprene 450 latex coloured with a yellow pigment, dissected and analysed. Three euthanized animals were perfused with a barium sulfate solution (1 g mL-1 ) associated with latex Neoprene 450 at a 1:3 ratio to obtain contrast-enhanced radiographs. The abdominal aorta emitted the celiac artery, which in turn originated the left gastric, hepatic and splenic arteries. The second collateral branch comprised the cranial mesenteric artery, followed by the renal arteries, which emitted the adrenal arteries, with the caudal emergence of the gonadal arteries. The caudal mesenteric artery appeared in a caudal direction. The abdominal aorta divided after reaching the pelvic cavity entrance, originating the right and left common iliac arteries. Before its bifurcation, the abdominal aorta dorsocaudally emitted its last collateral branch, the median sacral artery. The collateral branches of the aorta, therefore, resemble previously described rodent patterns, with few variations.

Successful treatment of focal renal artery fibromuscular dysplasia by balloon dilatation demonstrated via fractional flow reserve

We present a rare case of fibromuscular dysplasia (FMD) manifesting in the mid segment of right renal artery, which led to the development of refractory hypertension. The patient received balloon angioplasty to a severe lesion on the middle of right renal artery and subsequently had normalisation of blood pressures. Fractional flow reserve (FFR) detection of the renal artery before and after balloon dilatation was 0.71 and 0.98, respectively. The patient showed renal artery stenosis (RAS) with distal tumour-like dilatation, and multiple tortuosity and stenosis in carotid artery and coronary artery. At follow-up 2 months later, her blood pressures had normalised.

The Effect of Maternal Lower Limb Compression on Amniotic Fluid Index, Uteroplacental Perfusion, and Fetal Blood Flow in Isolated Oligohydramnios

INTRODUCTION

The aim of this study was to examine the efficacy of pneumatic compression of the maternal lower extremities in increasing the amniotic fluid index (AFI) in pregnancies complicated by isolated oligohydramnios.

METHODS

Women with isolated oligohydramnios (AFI <5 cm) at 32-41 weeks of pregnancy were connected to a sequential compression device for 60 min. Prior and after the application, AFI and the pulsatility index (PI) of a number of arteries were measured.

RESULTS

The median (interquartile range) maternal age of the 21 women included was 29 years (26.50-32.00), the median parity was 1 (1-2), and the median gestational age at intervention was 37.60 weeks (37.00-39.40). The median AFI increased after the application from 4.00 (3.62-4.50) to 6.08 cm (4.90-7.03) (p < 0.001). The median PI of the fetal renal artery decreased from 2.30 (2.01-2.88) to 2.26 (1.68-2.71) (p = 0.01). The hourly fetal urine production did not increase. Changes were not significant in the PI of the umbilical artery, the middle cerebral artery, and the bilateral uterine arteries.

CONCLUSION

Short-term activation of pneumatic compression on maternal lower extremities could increase the AFI in women with isolated oligohydramnios.

Renal artery infarction in the SARS-Cov-2 era: A systematic review of case reports

AIM

Renal artery infarction (RI) is the presence of blood clot in the main renal artery or its branches causing complete or partial obstruction of the blood supply. Its etiology is either related with disorders of the renal vasculature or with cardiovascular diseases. Recently, the SARSCoV- 2 virus is an emerging cause of thromboembolic events and the incidence of RI is anticipated to increase after the pandemic.

METHODS

A systematic review based on COVID-19 associated RI was conducted.

PROTOCOL

A systematic review of the Medline/Pubmed and Scopus databases was conducted in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (the PRISMA statement). Search strategy and information sources: A hand-search was performed using the terms "SARS-Cov-2" OR "COVID-19" AND "renal thrombosis" OR "renal infarction" OR "renal "thromboembolism".

ELIGIBILITY CRITERIA

all types of publications (case reports, case series, letters to the editor, short communications) were evaluated for relevance. Inclusion criteria were: confirmed SARS-Cov-2 infection irrespectively of the age, diagnosis of RI during or after the onset of viral infection, and exclusion of other potential causes of thromboembolic event except of SARS-Cov-2. Patients with renal transplantation were also considered. Study criteria selection: after checking for relevance based on the title and the abstract, the full texts of the selected papers were retrieved and were further evaluated. Duplicated and irrelevant cases were excluded. Any disagreement was resolved by consensus with the involvement of a third reviewer. Quality of studies: The assessment of the quality case reports was based on four different domains: selection, ascertainment, casualty and reporting. Each paper was classified as "Good", "Moderate" and "Poor" for any of the four domains. Data extractions: Crucial data for the conduct of the study were extracted including: age, sex, time from SARS-Cov-2 infection till RI development, medical history, previous or current antithrombotic protection or treatment, laterality and degree of obstruction, other sites of thromboembolism, treatment for thromboembolism and SARS-Cov-2 and final outcome.

DATA ANALYSIS

methods of descriptive statistics were implicated for analysis and presentation of the data.

RESULTS

The systematic review retrieved 35 cases in 33 reports. In most cases, RI was diagnosed within a month from the SARSCov- 2 infection albeit 17 out of 35 patients were receiving or had recently received thromboprophylaxis. Right, left, bilateral and allograft obstruction was diagnosed in 7, 15, 8 and 5 patients respectively. 17 cases experienced additional extrarenal thromboembolism primarily in aorta, spleen, brain and lower limbs. Low molecular weight heparins (LMWH) (usually 60-80 mg enoxaparine bid) was the primary treatment, followed by combinations of unfractionated heparin and salicylic acid, apixaban and rivaraxaban, warfarin, acenocoumarol or clopidogrel. Kidney replacement therapy was offered to five patients while invasive therapies with thrombus aspiration or catheter directed thrombolysis were performed in two. Regarding the outcomes, five of the patients died. The total renal function was preserved in 17 cases and renal impairment with or without hemodialysis was recorded in 5 patients, two of them having lost their kidney allografts.

LIMITATIONS

The majority of included studies are of moderate quality. The results and the conclusions are based on case-reports only and crucial data are dissimilarly presented or missing through the relevant publications.

CONCLUSIONS

Thromboprophylaxis may not offer adequate protection against SARS-Cov-2 induced thrombosis. Most patients could be effectively treated with conservative measures, while in more severe cases aggressive treatment could be recommended.

IMPLICATIONS OF KEY FINDINGS

Therapeutic doses of LMWH could be considered for protection against RI in SARS-Cov-2 cases. Interventional treatment could be offered in a minority of more severe cases after carful balancing the risks and benefits.

Pickering Syndrome: An Overlooked Renovascular Cause of Recurrent Heart Failure

ABSTRACTRecurring and rapidly developing (flash) pulmonary edema is the hallmark of Pickering syndrome, affecting patients with hypertension and atherosclerotic renal artery stenosis (either bilateral or unilateral) in a solitary functioning kidney, and impaired renal function. We herein report on a series of consecutive patients with recurrent hospital admissions for pulmonary edema, impaired renal function (chronic kidney disease class 4-5), and atherosclerotic bilateral renal artery stenosis, in whom Pickering syndrome had been long neglected. We also describe a streamlined diagnostic strategy entailing little or no need for contrast medium, thus carrying no risks of further worsening of renal function. This allowed us to make the correct diagnosis and opened the way to revascularization by percutaneous transluminal renal angioplasty with stent, which provided swift recovery of kidney function with resolution of pulmonary congestion and long-term pulmonary edema- and dialysis-free survival in all cases. In summary, these findings support the following key messages: (1) considering the diagnosis of Pickering syndrome, followed by searching atherosclerotic renal artery stenosis, is an essential step toward a life-saving revascularization that avoids dialysis and an otherwise poor outcome; and (2) a simplified strategy entailing little or no need for contrast medium, carrying no associated risks of deteriorating renal function, permits the diagnosis of Pickering syndrome.

Successful treatment of multidrug-resistant hypertension with catheter-based renal denervation in a patient with a renal artery stent

Renal artery stenting (RAS) and its effectiveness in the treatment of atherosclerotic renal artery disease are controversial.1 Catheter-based renal denervation (RDN) has been shown to reduce blood pressure in the treatment of multidrug-resistant hypertension.2 In this case, we presented the successful regulation of multidrug resistant hypertension after renal denervation in a patient with renal artery stent.

Recurrent flash pulmonary edema in unilateral renal artery stenosis with contralateral kidney shrinkage: A case report

RATIONALE

Flash pulmonary edema is a critical medical condition characterized by sudden and severe fluid accumulation in the lungs, which poses an immediate and life-threatening emergency. This can arise from a variety of underlying causes. This manuscript presents a case of recurrent pulmonary edema that was successfully managed through the insertion of a renal artery stent.

PATIENT CONCERNS

A 78-year-old woman visited the emergency room with recurrent acute dyspnea. Computed tomography renal angiography revealed renal artery stenosis of a single-functioning kidney.

DIAGNOSES

Flash pulmonary edema caused by renal artery stenosis of a functioning single kidney.

INTERVENTIONS

Percutaneous transluminal angioplasty and stenting were performed for the renal artery stenosis.

OUTCOMES

The patient's kidney function rapidly improved, and she has been free of flash pulmonary edema for 2 years.

LESSONS

Flash pulmonary edema can have various causes and can immediately be a life-threatening emergency. However, it can be treated with percutaneous revascularization if it is caused by renal artery stenosis. This case report reinforces the importance of accurate and immediate diagnosis when dealing with flash pulmonary edema. This case emphasizes the potential therapeutic benefit of renal artery stenting in the management of flash pulmonary edema caused by renal artery stenosis in patients with a single-functioning kidney.

Effects of liraglutide on extraglycemic inflammatory markers and renal hemodynamic parameters in diabetic kidney disease (DKD)

Diabetic kidney disease (DKD) was the leading cause of kidney disease, which has been a crucial public health. Liraglutide is a drug, widely used for DKD treatment globally. However, the extraglycemic inflammatory markers and renal hemodynamic parameters of DKD patients treated with liraglutide has been not reported. In this study, 160 patients with early DKD were enrolled, 80 cases in the control group and 80 cases in the treatment group, respectively. The individuals in the control group were treated with metformin, while the individuals in the treatment group were treated with liraglutide and metformin for 3 months. The urinary microalbumin and urinary creatinine was measured to calculate the ratio (UACR), while the Doppler ultrasound were measured before and after treatment. After 3 months of treatment, body mass index (BMI), waist circumference (WC) and low-density lipoprotein cholesterol (LDL) in the treatment group were significantly decreased compared with before and after treatment in the control group; the levels of cystatin and UACR in treatment group were lower than before treatment and control group; The end-diastolic blood flow velocity (EDV) of renal artery and segment artery in treatment group was significantly higher than that before treatment and control group; The levels of CRP, TNF-α and IL-6 in the treatment group after treatment were lower than those before treatment and those in the control group. After 3 months of treatment, blood cystatin in the treatment group decreased significantly compared with before treatment and after treatment in the control group, with statistical significance After 3 months of treatment, the EDV of renal artery and renal segment in treatment group was significantly higher than that before treatment and control group, the peak systolic blood flow velocity (PSV) and EDV of renal interlobar artery in treatment group were significantly higher than those before treatment and control group. The resistance index (RI) was significantly lower than that before treatment and control group. Liraglutide can reduce inflammatory indicators, renal artery blood flow and renal function indicators in early DKD patients.

Endovascular Repair of Traumatic Infrarenal Aortic Injury in an 8-Year-Old

The patient is an 8 year-old male presenting to outside facility following high-speed motor vehicle collision in which he was a restrained passenger. CT imaging at that time demonstrated a traumatic infrarenal aortic pseudoaneurysm, extensive pneumoperitoneum and free fluid, and an unstable L2 vertebral body fracture. He underwent exploratory laparotomy with small bowel resection prior to transfer. The patient was left in discontinuity and temporary closed. Vascular surgery was consulted upon arrival to tertiary care children's hospital. The decision was made to proceed with emergent endovascular repair. An aortogram confirmed the location of the aortic disruption well below the renal arteries, superior to the bifurcation. An 11 mm × 5 cm Viabahn covered stent was placed across the injury with adequate proximal and distal seal. This is a case of seatbelt-related pediatric infrarenal aortic injury in the setting of polytrauma. Endovascular repair was pursued in this damage-control setting.

Renal hemodynamics in patients with resistant hypertension and type 2 diabetes mellitus

Aim    To study renal hemodynamics in patients with resistant arterial hypertension (RAH) in combination with type 2 diabetes mellitus (DM2) and to identify factors involved in the increase in intrarenal vascular resistance.Material and methods    This study included 59 patients (25 men) with RAH in combination with DM2. Mean age of patients was 60.3±7.9 years; 24-h blood pressure (24-BP) (systolic, diastolic, SBP/DBP) was 158.0±16.3 / 82.5±12.7 mm Hg during the treatment with 4.3 [4.0;5.0] antihypertensive drugs; glycated hemoglobin (HbA1c) was 7.5±1.5 %; estimated glomerular filtration rate (eGFR) was 73.1±21.8 ml/min / 1.73 m2 (CKD-EPI equation). Measurement of office BP, 24-h BP monitoring, renal artery (RA) Doppler, routine lab tests including determination of GFR (CKD-EPI), 24-h urine albumin excretion, and ELISA measurement of blood lipocalin-2, cystatin C, high-sensitive C-reactive protein (hsCRP), and asymmetric dimethylarginine (ADMA) were performed for all patients.Results    Incidence of increased RA resistive index (RI) was 39% despite the high rate of vasodilator treatment (93% for renin-angiotensin-aldosterone system inhibitors, 78% for calcium antagonists). According to a correlation and regression analysis, RA RI values were correlated with the kidney function (r=-0.46, p<0.001 for eGFR, r=0.56; p=0.006 for lipocalin-2), age (r=0.54, p<0.001), increases in concentrations of hsCRP (r=0.35, p<0.001) and ADMA (r=0.39, p=0.028), the increase in vascular stiffness (r=0.59, p<0.001 for pulse BP (PBP) as well as DM2 duration, and HbA1c (r=0.33, p<0.001 for both). The independent association of RA RI with the age, PBP, and duration of DM2 was confirmed by the results of multivariate regression analysis. According to the ROC analysis, the threshold level of RA RI corresponding to a decrease in GFR <60 ml / min / 1.73 m2 was ≥0.693 conv. units.Conclusion    In more than one third of patients with RAH in combination with DM2, increased renal vascular resistance was documented, which was closely associated with impaired kidney function, age, DM2 duration and severity, and markers of low-grade inflammation, endothelial dysfunction, and vascular stiffness. The value of RA RI ≥0.693 conv. units was a threshold for the development of chronic kidney disease (CKD).

Predicting renal function response to renal artery stenting

OBJECTIVE

The Cardiovascular Outcomes in Renal Atherosclerotic Lesions Trial found no benefit of renal artery stenting (RAS) over medical therapy, although it was underpowered to detect a benefit among patients with chronic kidney disease (CKD). A post hoc analysis demonstrated improved event-free survival after RAS for patients whose renal function improved by 20% or more. A significant obstacle to achieving this benefit is the inability to predict which patients' renal function will improve from RAS. The objectives of the current study were to identify predictors of renal function response to RAS.

METHODS

The Veteran Affairs Corporate Data Warehouse was queried for patients who underwent RAS between 2000 and 2021. The primary outcome was improvement in renal function (estimated glomerular filtration rate [eGFR]) after stenting. Patients were categorized as responders if the eGFR at 30 days or greater after stenting increased by 20% or more compared with before stenting. All others were nonresponders.

RESULTS

The study cohort included 695 patients with a median follow-up of 7.1 years (interquartile range, 3.7-11.6 years). Based on postoperative change in eGFR, 202 stented patients (29.1%) were responders, and the remainder (n = 493 [70.9%]) were nonresponders. Before RAS, responders had a significantly higher mean serum creatinine, lower mean eGFR, and higher rate of decline of preoperative GFR in the months before stenting. After stenting, responders had a 26.1% increase in eGFR, compared with before stenting (P < .0001), which remained stable during follow-up. In contrast, nonresponders had a progressive 5.5% decrease in eGFR after stenting. Logistic regression analysis identified three predictors of renal function response to stenting: (1) diabetes (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.44-0.91; P = .013), (2) CKD stages 3b or 4 (OR, 1.80; 95% CI, 1.26-2.57; P = .001), and (3) rate of decline in preoperative eGFR per week before stenting (OR, 1.21; 95% CI, 1.05-1.39; P = .008). CKD stages 3b and 4 and the rate of decline in preoperative eGFR are positive predictors of renal function response to stenting, whereas diabetes is a negative predictor.

CONCLUSIONS

Based on our data, patients in CKD stages 3b and 4 (eGFR 15-44 mL/min/1.73 m2) are the only subgroups with a significant probability of improved renal function after RAS. The rate of decline of preoperative eGFR over the months before stenting is a powerful discriminator of patients who are most likely to benefit from RAS. Specifically, patients with a more rapid decrease in eGFR before stenting have a significantly greater probability of improved renal function with RAS. In contrast, diabetes is a negative predictor of improved renal function, so interventionalists should be circumspect about RAS in diabetic patients.

Impaired renal ischemia reperfusion recovery after bilateral renal artery ligation in rats treated with adenine: role of renal mitochondria

Vascular calcification (VC) and ischemia reperfusion (IR) injury is characterised to have mitochondrial dysfunction. However, the impact of dysfunctional mitochondria associated with vascular calcified rat kidney challenged to IR is not explored and is addressed in the present study. Male Wistar rats were treated with adenine for 20 days to induce chronic kidney dysfunction and VC. After 63 days, renal IR protocol was performed with subsequent recovery for 24 h and 7 days. Various mitochondrial parameters and biochemical assays were performed to assess kidney function, IR injury and its recovery. Adenine-induced rats with VC, decreased creatinine clearance (CrCl), and severe tissue injury demonstrated an increase in renal tissue damage and decreased CrCl after 24 h of IR (CrCl in ml: IR-0.220.02, VC-IR-0.050.01). Incidentally, the 24 h IR pathology in kidney was similar in both VC-IR and normal rat IR. But, the magnitude of dysfunction was higher with VC-IR due to pre-existing basal tissue alterations. We found severed deterioration in mitochondrial quantity and quality supported by low bioenergetic function in both VC basal tissue and IR challenged sample. However, post 7 days of IR, unlike normal rat IR, VC rat IR did not improve CrCl and corresponding mitochondrial damage in terms of quantity and its function were observed. Based on the above findings, we conclude that IR in VC rat adversely affect the post-surgical recovery, mainly due to the ineffective renal mitochondrial functional restoration from the surgery.

A Case of Hypokalemia Caused by Left Native Renal Artery Stenosis in a Kidney Transplant Recipient

A 39-year-old woman with end-stage renal failure of unknown origin was on peritoneal dialysis for 10 years. One year ago, she underwent ABO-incompatible living-donor kidney transplantation from her husband. After the kidney transplantation, her serum creatinine level remained around 0.7 mg/dL, but her serum potassium level remained low at around 3.5 mEq/L despite potassium supplementation and spironolactone. The patient's plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were markedly elevated (20 ng/mL/h and 868 pg/mL, respectively). A CT angiogram of the abdomen performed 1 year previously suggested stenosis of the left native renal artery, which was considered responsible for the hypokalemia. Renal venous sampling was done on both the native kidneys and the transplanted kidney. Since renin secretion from the left native kidney was significantly elevated, a laparoscopic left nephrectomy was performed. Postoperatively, the renin-angiotensin-aldosterone system was markedly improved (PRA: 6.4 ng/mL/h, PAC: 147.3 pg/mL), and the serum potassium levels also improved. Pathological examination of the removed kidney showed many atubular glomeruli and hyperplasia of the juxtaglomerular apparatus (JGA) in residual glomeruli. In addition, renin staining showed strong positivity in the JGA of these glomeruli. Here, we report a case of hypokalemia caused by left native renal artery stenosis in a kidney transplant recipient. This valuable case study provides histological confirmation of maintained renin secretion in an abandoned native kidney after kidney transplantation.

Optimal Renal Artery-Aorta Angulation Revealed by Flow Simulation

INTRODUCTION

In the circulatory system, the vessel branching angle may have hemodynamic consequences. We hypothesized that there is a hemodynamically optimal range for the renal artery's branching angle.

METHODS

Data on the posttransplant kinetics of estimated glomerular filtration rate (eGFR) were analyzed according to the donor and implant sides (right-to-right and left-to-right position; n = 46). The renal artery branching angle from the aorta of a randomly selected population was measured using an X-ray angiogram (n = 44). Computational fluid dynamics simulation was used to elucidate the hemodynamic effects of angulation.

RESULTS AND DISCUSSION

Renal transplant patients receiving a right donor kidney to the right side showed faster adaptation and higher eGFR values than those receiving a left donor kidney to the right side (eGFR: 65 ± 7 vs. 56 ± 6 mL/min/1.73 m2; p < 0.01). The average branching angle on the left side was 78° and that on the right side was 66°. Simulation results showed that the pressure, volume flow, and velocity were relatively constant between 58° and 88°, indicating that this range is optimal for the kidneys. The turbulent kinetic energy does not change significantly between 58° and 78°.

CONCLUSION

The results suggest that there is an optimal range for the renal artery's branching angle from the aorta where hemodynamic vulnerability caused by the degree of angulation is the lowest, which should be considered during kidney transplantations.

Spontaneous Multiple Arterial Dissection in a COVID-19-Positive Decedent

ABSTRACT

Spontaneous multiple arterial dissection (SMAD) is a rarely reported phenomenon and has been previously linked to connective tissue diseases and specifically the genetic mutations in SMAD3 and COL3A1. Herein we describe a case of SMAD with scattered thrombi in a COVID-19-positive patient with a history of unspecified mitochondrial myopathy. Vasculopathy involved the splenic artery, inferior mesenteric artery, internal mammary arteries, omental arteries, mesenteric arteries, and small renal arteries. Dissections were confirmed by histology in the splenic artery, inferior mesenteric artery, and bilateral renal medullary arteries. Genetic studies were done to rule out SMAD3 and COL3A1 mutations. Because the Smad3 protein has been previously implicated in COVID-19-associated tissue fibrosis, it may play a role in endothelial dysfunction as well.

When Bodybuilding Goes Wrong—Bilateral Renal Artery Thrombosis in a Long-Term Misuser of Anabolic Steroids Treated with AngioJet Rheolytic Thrombectomy

Bilateral renal infarction is an extremely rare condition with only few cases reported in the literature. We present a case of bilateral renal infarction affecting an otherwise healthy 34 year old bodybuilder chronically misusing testosterone and stanozolol. The patient presented with severe flank pain mimicking renal colic and biochemical features of acute kidney injury. Diagnostic workup revealed thrombosis affecting both renal arteries. Subsequently, the patient underwent a percutaneous rheolytic thrombectomy with AngioJet catheter, along with catheter-directed thrombolysis. Right-sided retroperitoneal hematoma developed as an early complication, mandating surgical exploration and nephrectomy due to kidney rupture and the unstable condition of the patient. Intensive care and continuous renal replacement therapy were instigated until a gradual improvement of the patient status and a return of kidney function was achieved. No abnormalities were found in the cardiological and hematological evaluation. We believe this is a first report of bilateral renal infarction associated with anabolic steroid misuse in an otherwise healthy individual, and a first report of AngioJet thrombectomy in bilateral thrombosis of renal arteries. It stresses the importance of a thorough diagnostic workup of colic patients and emphasizes the need for sports medicine to reach out to amateur athletes with education on the harms of doping.

Long-Term Continuous Measurement of Renal Blood Flow in Conscious Rats

The kidneys play a crucial role in maintaining the homeostasis of body fluids. The regulation of renal blood flow (RBF) is essential to the vital functions of filtration and metabolism in kidney function. Many acute studies have been carried out in anesthetized animals to measure RBF under various conditions to determine mechanisms responsible for the regulation of kidney perfusion. However, for technical reasons, it has not been possible to measure RBF continuously (24 h/day) in unrestrained unanesthetized rats over prolonged periods. These methods allow the continuous determination of RBF over many weeks while also simultaneously recording blood pressure (BP) with implanted catheters (fluid-filled or by telemetry). RBF monitoring is carried out with rats placed in a circular servo-controlled rat cage that enables the unrestrained movement of the rat throughout the study. At the same time, the tangling of cables from the flow probe and arterial catheters is prevented. Rats are first instrumented with an ultrasonic flow probe placement on the left renal artery and an arterial catheter implanted in the right femoral artery. These are routed subcutaneously to the nape of the neck, and connected to the flowmeter and pressure transducer, respectively, to measure RBF and BP. Following surgical implantation, rats are immediately placed in the cage to recover for at least one week and stabilize the ultrasonic probe recordings. Urine collection is also feasible in this system. The surgical and post-surgical procedures for continuous monitoring are demonstrated in this protocol.

[Misdiagnosis of Acute Renal Artery Thrombosis as Acute Abdominal Disease:Report of One Case]

Renal artery thrombosis can cause acute occlusion of unilateral or bilateral renal arteries,and kidney failure would be induced if it is not diagnosed and treated in time.Therefore,rapid and correct treatment is especially important for renal artery thrombosis.Due to the lack of specificity of clinical manifestations,this disease in commonly misdiagnosed or missed and thus has a low early diagnosis rate.Here we report a case of acute renal artery thrombosis to improve the diagnosis and treatment.

Renal interstitial fibrosis is reduced in high-fat diet-induced obese pigs following renal denervation from the intima and adventitia of the renal artery

Background This study aims to compare whether two different routes of Renal denervation (RDN) from the intima and adventitia of the renal artery can reduce renal fibrosis in a pig model of hypertension induced by a high-fat diet and to explore possible molecular mechanisms. Methods Twenty-four Bama miniature pigs were randomly divided into a control group (normal diet, n=6) or a hypertension model group (high-fat diet, n=18). The model group was randomly divided into the intima-RDN group (n=6), the adventitia-RDN group (n=6), or the renal arteriography only group (sham group, n=6). All animals were fed separately. The model group was fed a high-fat diet after the operation, and the control group was fed conventionally for 6 months. After 6 months, renal artery angiography was performed again to observe the condition of the renal arteries, after which all animals were euthanized. The blood pressure (BP) and blood biochemical results of each group were evaluated 6 months after the operation; kidney tissue morphology and collagen fiber content were examined by hematoxylin-eosin (HE) staining and Masson staining; Superoxide dismutase (SOD) activity and the malondialdehyde (MDA) content of kidney tissue were assessed by a biochemical enzyme method; the protein expression level of transforming growth factor-β 1 (TGF-β1), α smooth muscle actin (αSMA) and Smad3 were assessed by Western blot; and electron microscopy was used to examine changes in kidney microstructure. Results After 6 months of a high-fat diet, the blood lipid levels of the model group were significantly higher compared to baseline and to that of the control group during the same period (all showed P<0.05); the blood lipid levels of the control group did not change significantly from baseline (P>0.05). The degree of glomerular damage caused by hyperlipidemia in the intima-RDN group and the adventitia-RDN group was significantly lower than that of the sham and control groups, and the renal fibrosis area percentage was also significantly lower (P<0.05). Electron microscopy showed that both the intima-RDN group and the adventitia-RDN group had a more even distribution of chromosomes and less mitochondrial swelling compared with the sham group. Conclusion RDN from the adventitia of the renal artery and RDN from the intima of the renal artery have the similar advantages of delaying high fat-induced renal fibrosis. The anti-fibrotic effect of RDN may be related to inhibition of the TGF-β1/smad3 pathway.

[Renal allograft transplant vascular complications. Diagnostic and treatment.]

Vascular complications remain common after renal transplantation, occurring in 3% to 15% of patients. These complications can compromise graft function,with graft loss rates ranging from 12.6 to 66.7%.Vascular abnormalities of the graft, specifically the presence of multiple vessels, represent the most frequently studied risk factor for the development of vascular complications. Other risk factors identified for the development of vascular complications are linked to the characteristics of the recipient, or thromboembolic diseasesharing atherosclerosis and/or hypercoagulant state aspathogenic features.Although the most frequent vascular complication is renal artery stenosis, we will also address the complications according to their early or late on set in order to highlightthe potentially more severe complications that may affectgraft survival during the follow-up period.Early vascular complications include mainly arterial and venous thrombosis and lacerations or disruptions of artery and/or vein, as well as arterio-venous fistulas or intrarenal pseudoaneurysms. In contrast, late-onset complications include stenosis or kinking of the renal artery-and less commonly of the renal vein-, as well as extrinsic compression as a consequence of the presence of perigraft fluid collections. Finally, extrarenal pseudoaneurysm is a potentially severe complication in the late post-transplant period.Finally, this article explores special transplant situations such as complications derived from the paediatric donor in adult recipients, transplantation in the paediatric recipient and emerging techniques like robotic renal transplantation.

[Management of abdominal aortic aneurysms]

MANAGEMENT OF ABDOMINAL AORTIC ANEURYSMS The abdominal aortic aneurysm is a permanent dilation of the aorta with a diameter of more than 30 mm. It can be strictly infra-renal or be located opposite the origin of the digestive and renal arteries (complex aneurysm). Most often fortuitous, the diagnosis must seek a secondary location of the aneurysmal disease (thoracic aorta, popliteal artery) as well as other manifestations of atheromatous disease. The natural course of the aneurysm is rupture, the severity of which is such that preventive and elective surgical treatment is warranted when the aneurysm reaches 55 mm or if it grows rapidly. Regular monitoring of the diameter by Doppler ultrasound is necessary when the diameter is less than 45 mm; beyond this threshold, a CT angiogram and a specialist consultation in vascular surgery are necessary. Flattening - graft and stent exclusion are the two possible surgical options; the anatomy of the aneurysm and the patient's comorbidities determine the choice of surgical technique.

Abdominal vessel depiction on virtual triphasic spectral detector CT: initial clinical experience

Purpose

To evaluate vessel assessment in virtual monoenergetic images (VMI_40keV) and virtual-non-contrast images (VNC) derived from venous phase spectral detector computed tomography (SDCT) acquisitions in comparison to arterial phase and true non-contrast (TNC) images.

Methods

Triphasic abdominal SDCT was performed in 25 patients including TNC, arterial and venous phase. VMI_40keV and VNC were reconstructed from the venous phase and compared to conventional arterial-phase images (CI_art), TNC and conventional venous-phase images (CI_ven). Vessel contrast and virtual contrast removal were analyzed with region-of-interest-based measurements and in a qualitative assessment.

Results

Quantitative analysis revealed no significant attenuation differences between TNC and VNC in arterial vessels (p-range 0.07–0.47) except for the renal artery (p = 0.011). For venous vessels, significant differences between TNC and VNC were found for all veins (p < 0.001) except the inferior vena cava (p = 0.26), yet these differences remained within a 10 HU range in most patients. No significant attenuation differences were found between CI_art/VMI_40keV in arterial vessels (p-range 0.06–0.86). Contrast-to-noise ratio provided by VMI_40keV and CI_art was equivalent for all arterial vessels assessed (p-range 0.14–0.91).

Qualitatively, VMI_40keV showed similar enhancement of abdominal and pelvic arteries as CI_art and VNC were rated comparable to TNC.

Conclusion

Our study suggests that VNC and VMI_40keV derived from single venous-phase SDCT offer comparable assessment of major abdominal vessels as provided by routine triphasic examinations, if no dynamic contrast information is required.

Long-Term Effects of Renal Artery Denervation

Background and Objectives: Renal artery denervation (RDN) procedure is a broadly discussed method in the treatment of resistant hypertension. Many studies report short-term (3-12 months) results for blood pressure and arterial stiffness. The primary endpoints were changes in 24 h mean systolic blood pressure (BP) and office systolic BP 48 months after RDN. The secondary endpoints were changes in aortic pulse wave velocity and impact of polypharmacy on these variables. Materials and Methods: Renal artery denervation was performed in 73 patients treated for resistant hypertension; 49 patients remained in final analysis. Patient examination was carried out before the procedure, and subsequently at 3, 6, 12, 24, and 48 months later. Patients' antihypertensive and overall medication regimens were carefully analysed. Results: Mean 24 h arterial blood pressure lowered and was sustained at lower levels for up to 48 months; median (interequartile range-IQR) from 158(23.5)/100(14.2) to 140(26.5)/86(16.2) mmHg. Mean reduction in 24 h ambulatory systolic BP was -11 ± 25 mmHg (95% CI, -20 to -2; p < 0.001), while office systolic BP reduced by -7 ± 23 mmHg (95%CI, -24 to -1; p < 0.02). A significant reduction in median aortic pulse wave velocity 12 months after the procedure (drop from baseline 11.2 [3.15] m/s (95%CI 6.1 to 16.2) to 9.8 [2.1] m/s (95%CI 6.1 to 13.7; p = 0.002)). After 48 months, there was no worsening compared to the baseline level of 10.3 [4.0] m/s (95% CI 6.9 to 17.8) (p > 0.05). The total mean number of antihypertensive drugs remained unchanged: 5.97(±1.1) vs. 5.24 (±1.45). A higher number of pills after 48 months was associated with higher aortic pulse wave velocity (1-5 pill group: 8.1 ± 1.6 m/s; 6-10 pill group: 10.9 ± 1.8 m/s; >11 pill group: 15.1 ± 2.6 m/s) (p = 0.003). Conclusions: Antihypertensive effect after renal denervation lasts up to 48 months with no worsening of arterial stiffness compared to baseline. In our study, polypharmacy was associated with increased arterial stiffness 48 months after the procedure.

Comparison of renal function after Endovascular Aneurysm Repair and Open Aneurysm Repair in patients treated with abdominal aortic aneurysm below the renal artery

INTRODUCTION

In addition to open endoaneurysmorrhaphy (EA) for treating the abdominal aortic aneurysm (AAA), other approaches such as endovascular aneurysm repair (EVAR) is gaining attention. Renal dysfunction could be a complication of these surgical techniques. We decided to compare renal function in EVAR vs. EA in patients operated for infrarenal AAAs.

METHODS

Two groups of patients with AAA were included in this retrospective study. The first group (28 cases) consisted of patients who underwent AAA repair by EA technique and the second group included 12 patients who underwent EVAR for AAA repair. Serum creatinine levels measured one week, one month, three months, six months, and one year after the surgeries were documented. Through calculating the glomerular filtration rate (GFR) and scoring by the RIFLE criteria (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease), the patients' renal function was evaluated.

RESULTS

Of 40 patients included, three cases had diabetes mellitus (7.5%), 16 cases had hypertension (40%), 16 were smokers (40%), and 12 cases had a ruptured AAA (30%). The mean time of onset or increase of renal dysfunction compared to baseline in both groups was 6.45 days. The lowest time for patients with renal dysfunction (GFR less than 60) was from the onset and the highest time was 90 days after surgery. GFR of patients before surgery (76.9 in the EVAR group, vs. 56.2 in the EA group; P = 0.015) and one year after the surgery (84.1 in the EVAR group, vs. 57.7 in the EA group; P = 0.027) was differed significantly. The RIFLE criterion also was significantly different at the end of the first year in the two groups (P = 0.042).

CONCLUSION

Based on the results, we concluded that the changes in renal function in EA group were more than EVAR group during one year. It may be necessary to follow patients undergoing these surgeries for a longer period to understand the prognosis of these patients better.

Renin Cells, the Kidney, and Hypertension

Renin cells are essential for survival perfected throughout evolution to ensure normal development and defend the organism against a variety of homeostatic threats. During embryonic and early postnatal life, they are progenitors that participate in the morphogenesis of the renal arterial tree. In adult life, they are capable of regenerating injured glomeruli, control blood pressure, fluid-electrolyte balance, tissue perfusion, and in turn, the delivery of oxygen and nutrients to cells. Throughout life, renin cell descendants retain the plasticity or memory to regain the renin phenotype when homeostasis is threatened. To perform all of these functions and maintain well-being, renin cells must regulate their identity and fate. Here, we review the major mechanisms that control the differentiation and fate of renin cells, the chromatin events that control the memory of the renin phenotype, and the major pathways that determine their plasticity. We also examine how chronic stimulation of renin cells alters their fate leading to the development of a severe and concentric hypertrophy of the intrarenal arteries and arterioles. Lastly, we provide examples of additional changes in renin cell fate that contribute to equally severe kidney disorders.

The effect of renal artery-only or renal artery-vein clamping during partial nephrectomy on short and long-term functional results: Is clamping technique important?

PURPOSE

To evaluate the effect of artery-only (AO) and artery-vein (AV) clamping during partial nephrectomy (PN) on short- and long-term renal function outcome.

METHODS

Medical records of 154 patients in the AO group and 192 patients in the AV group who underwent open and minimally invasive (laparoscopic/robotic) PN between January 2011 and January 2018 were retrospectively assessed. Preoperative patient and tumor-specific characteristics in addition to perioperative factors and renal function outcomes were compared. The change in the estimated glomerular filtration rate (eGFR) from postoperative 1-3 days, 12 and 24 months after surgery was calculated. Acute kidney injury (AKI) was defined a as a > 25% reduction in eGFR.

RESULTS

There were no statistically significant differences between the clamping techniques in terms of postoperative 1-3 days, 12 and 24 months eGFR change percentage and risk of progression to chronic kidney disease (CKD). No significant difference in short- and long-term renal functions was found between the minimally invasive or open AO and AV clamping subgroups at any time point. In multivariate analysis, the R.E.N.A.L score (AO group p = 0.026, AV group p < 0.001) and preoperative eGFR (AO group p < 0.001, AV group p = 0.010) were strong predictors of the acute kidney injury in both groups. Older age (AO group p = 0.045, AV group p = 0.010) and preoperative eGFR (AO group p = 0.008, AV group p = 0.002) were significantly associated with CKD progression at 2-year follow-up in both groups.

CONCLUSION

AV clamping does not adversely affect postoperative renal function compared to AO clamping. Preoperative patient- and tumor-related factors are more important for renal function regardless of the clamping technique.

Image-guided study of swine anatomy as a tool for urologic surgery research and training

PURPOSE

To describe the anatomy of the swine urinary system using computed tomography and to discuss the role of this animal as an experimental model for urological procedures.

METHODS

Three male Landrace pigs underwent computed tomography and the anatomy of the urinary system and renal circulation was analyzed and described.

RESULTS

In all animals, 2 kidneys, 2 ureters and one bladder were identified. Each kidney presented a single renal artery vascularization, with a mean diameter on the right of 4.45 and 5.31 mm on the left (p < 0.0001) and single renal vein drainage, with a mean diameter on the right of 5.78 and 5.82 mm on the left (p = 0.0336). The average renal length was 9.85 cm on the right and 10.30 cm on the left (p < 0.0001). The average renal volume was 113.70 cm3 on the right and 109.70 cm3 on the left (p < 0.0001). The average length of the ureter was 19.78 cm on the right and 22.08 cm on the left (p < 0.0001). The average bladder volume was 423.70 cm3.

CONCLUSIONS

The data obtained show similarities with human anatomy, suggesting the viability of the swine model for planning preclinical trials, basic research, refinement in experimental surgery and surgical training for urological procedures.

COVID-19 as the cause of thrombosis: recognising COVID-19 infection in apparently asymptomatic patients

COVID-19 has serious thrombotic complications in critically ill patients; however, thrombus is not a typical presenting symptom. This case report describes a patient with no respiratory symptoms who presented to the emergency department with abdominal pain. The pain was attributed to renal thrombosis, but the patient was found to have no risk factors for thrombotic disease and subsequent hypercoagulable work-up was unremarkable. Pulmonary manifestations of COVID-19 infection were detected incidentally on the abdominal CT scan and confirmed via PCR test. The patient was isolated and went on to develop mild respiratory failure secondary to COVID-19 infection. This case suggests that unexplained thrombus in otherwise asymptomatic patients can be a direct result of COVID-19 infection, and serves as a call to action for emergency department clinicians to treat unexplained thrombotic events as evidence of COVID-19.

Thrombolysis as a treatment for transplant renal artery thrombosis - a report of three unsuccessful cases and an overview of reported cases

INTRODUCTION

Thrombolysis has been suggested as a feasible method to treat arterial renal transplant thrombosis under conditions of short duration of ischemia. Data on maximal duration of ischemia that are still feasible to treat are scarce.

METHODS

We retrospectively analysed our experience involving three attempts to utilize thrombolysis to treat transplant renal artery thrombosis. We searched through literature on PubMed and compared the data we found with our own experience.

RESULTS

In case number 1 of our cohort, thrombolysis was initiated 12 hours after the onset of thrombosis and had to be ceased after five hours due to the formation of a haematoma. Perfusion of the graft was restored but it did not regain function, most likely due to long ischemia time. In case number 2, an attempt to use thrombolysis was unsuccessful due to failure to cross the graft artery occlusion with a guidewire. Thrombosis was most likely caused by chronic rejection of the graft. In case number 3, thrombolysis restored arterial patency but, due to an onset of ischemia, which lasted 2 to 3 days, did not lead to restoration of graft function. The prolonged ischemia period in case three occurred, at least in part, due to failure to perform an ultrasound scan when the patient was first admitted.

CONCLUSION

We can confirm that thrombolysis for transplant renal artery thrombosis seems to be feasible only when the condition has a short duration. In the event of sudden deterioration of graft function, the absence of perfusion must always be ruled out by ultrasound scan.