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.

Evaluation and Management of Resistant Hypertension: Core Curriculum 2024.

Resistant hypertension is defined as blood pressure above goal despite confirmed adherence to 3 first-line antihypertensive agents or when blood pressure is controlled with 4 or more medications at maximal or maximally tolerated doses. In addition to meeting these criteria, identifying patients with true resistant hypertension requires both accurate in-office blood pressure measurement as well as excluding white coat effects through out-of-office blood pressure measurements. Patients with resistant hypertension are at higher risk for adverse cardiovascular events and are more likely to have a potentially treatable secondary cause contributing to their hypertension. Effective treatment of resistant hypertension includes ongoing lifestyle modifications and collaboration with patients to detect and address barriers to optimal medication adherence. Pharmacologic treatment should prioritize optimizing first-line, once daily, longer acting medications followed by the stepwise addition of second-, third-, and fourth-line agents as tolerated. Physicians should systematically evaluate for and address any underlying secondary causes. A coordinated, multidisciplinary team approach including clinicians with experience in treating resistant hypertension is essential. New treatment options, including both pharmacologic and device-based therapies, have recently been approved, and more are in the pipeline; their optimal role in the management of resistant hypertension is an area of ongoing research.

Effect of fenestration configuration on renal artery outcomes during fenestrated-branched endovascular aortic repair.

OBJECTIVE: The aim of this study was to evaluate the effect of fenestration configuration and fenestration gap on renal artery outcomes during fenestrated-branched endovascular aortic repair (F/BEVAR). METHODS: A retrospective multicenter analysis was performed, including patients with complex aortic aneurysms treated with F/BEVAR that incorporated at least one small fenestration to a renal artery. The renal fenestrations were divided into groups 1 (8 × 6 mm) and 2 (6 × 6 mm). Primary patency, target vessel instability (TVI), freedom from secondary interventions (SIs), occurrence of type IIIc endoleak, all related to the renal arteries, were analyzed at 30-day, 1-year, and 5-year landmarks. The fenestration gap (FG) distance was analyzed as a modifier, and clustering was addressed at the patient level. RESULTS: A total of 796 patients were included in this study, 71.7% male, with a mean age of 73.3 ± 8.1 years. The mean follow-up was 30.0 ± 20.6 months. Of the 1474 small renal fenestrations analyzed, 47.6% were 8 × 6 mm, and 52.4% were 6 × 6 mm. At the 30-day landmark, primary patency (99.9% vs 98.0%; P value < .001 for groups 1 and 2, respectively), freedom from TVI (99.6% vs 97.1%; P value < .001 for groups 1 and 2, respectively), and freedom from SI (99.8% vs 98.4%; P value = .022 for groups 1 and 2, respectively) were higher in 8 × 6 compared with 6 × 6 fenestrations, and the incidence of acute kidney injury was similar across the groups (92.6% vs 92.7%; P value = .953 for groups 1 and 2 respectively). The primary patency at 1 and 5 years was higher in 8 × 6 fenestrations (1-year: 98.8% vs 96.9%; 5-year: 97.8% vs 95.7%, for groups 1 and 2, respectively, P values = .010 and .021 for 1 and 5 year comparisons, respectively). The freedom from SIs was significantly higher among 6 × 6 fenestrations at 5 years (93.1% vs 96.4%, for groups 1 and 2, respectively, P value = .007). The groups were equally as likely to experience a type Ic endoleak (1.3% and 1.6% for 8 × 6 and 6 × 6mm fenestrations, respectively, P = .689). The 6 × 6 fenestrations were associated with higher risk of kidney function deterioration (17.8%) when compared with 8 × 6 fenestrations (7.6%) at 5 years (P < .001). The risk of type IIIc endoleak was significantly higher among 8 × 6 fenestrations at 5 years (4.9% and 2% for 8 × 6 and 6 × 6 mm fenestrations, respectively; P = .005). A FG ≥5 mm negatively impacted the cumulative 5-year freedom from TVI (group 1: FG ≥5 mm = 0.714, FG <5 mm = 0.857; P < .001; group 2: FG ≥5 mm = 0.761, FG <5 mm = 0.929; P < .001) and the cumulative 5-year freedom from type IIIc endoleak (group 1: FG ≥5 mm = 0.759, FG <5 mm = 0.921; P = .034; group 2: FG ≥5 mm = 0.853, FG <5 mm = 0.979; P < .001) in both groups and the cumulative 5-year patency in group 2 (group 1: FG ≥5 mm = 0.963, FG <5 mm = 0.948; P = .572; group 2: FG ≥5 mm = 0.905, FG <5 mm = 0.938; P = .036). CONCLUSIONS: Fenestration configuration for the renal arteries impacts outcomes. The 8 × 6 small fenestrations have better patency at 30 days, 1 year, and 5 years, whereas 6 × 6 small fenestrations are associated with lower rates of SIs, primarily due to a lower incidence of type IIIc endoleaks. FG ≥5 mm at the level of the renal arteries significantly impacts the freedom from TVI, freedom from type IIIc endoleak, and 5-year patency independently of the fenestration size or vessel diameter.

Natural history of visceral branch artery dissections and the influence of concurrent aortic dissection on overall and intervention-free survival.

OBJECTIVE: Visceral branch artery dissection (VBAD) is uncommon and may occur with or without an associated aortic dissection (AD). We hypothesized that isolated VBAD would have a more benign clinical course than those with concurrent AD and compared survival outcomes stratified based on aortic involvement. METHODS: VBAD over a 5-year period were identified using International Classification of Diseases codes. Data related to patient demographics, comorbid conditions, clinical presentation, management (including procedural interventions), and survival were obtained from medical records. Anatomic imaging studies were reviewed to characterize anatomy, including the presence or absence of concurrent AD. Overall survival and intervention-free survival were evaluated using Kaplan-Meier and Cox proportional hazards models. RESULTS: A total of 299 VBAD were identified, 174 of which were isolated VBAD and 125 were associated with concurrent AD. Seventy-one percent of patients were men, 77% were White, and 85% were non-Hispanic. The mean age was 61.1 ± 14.4 years. The mean follow-up was 53.2 ± 50.0 months. The estimated overall survival was 88.2% and the estimated overall intervention-free survival was 55.6% at 12 months. Isolated VBAD had better overall survival than those with concurrent AD (69.2% vs 32.4%; P < .001). Concurrent AD was also associated with inferior intervention-free survival (57.5% vs 7.3%; P < .001). Acute presentation was associated with decreased intervention-free survival (86.1% vs 13.4%; P < .001). Acute presentation was also associated with decreased overall survival in patients with isolated VBAD (60.8% vs 80.0% at 180 months; P < .001) and inferior intervention-free survival (48.4% vs 69.5% at 180 months; P < .001) in the subgroup of patients with isolated VBAD. Multivariable Cox models identified that age (hazard ratio [HR]: 1.05, standard deviation [SD]: 0.02; P = .001) was associated with inferior survival and renal dissections (HR: 3.08, SD: 0.99; P = .001) or mesenteric and renal dissections (HR: 3.39, SD: 1.44; P = .004) were associated with inferior intervention-free survival. CONCLUSIONS: Isolated VBAD has superior overall and intervention-free survival to those associated with concurrent AD. The absence vs presence of aortic involvement is useful for risk stratification and may support tailored approaches to the frequency of imaging surveillance.

Effect of Hypoxia Preconditioning on the Regenerative Capacity of Adipose Tissue Derived Mesenchymal Stem Cells in a Model of Renal Artery Stenosis.

Atherosclerotic renal artery stenosis (ARAS) is associated with irreversible parenchymal renal disease and regenerative stem cell therapies may improve renal outcomes. Hypoxia preconditioning (HPC) may improve the regenerative functions of adipose tissue-derived mesenchymal stem cells (AMSC) by affecting DNA 5-hydroxymethylcytosine (5hmC) marks in angiogenic genes. Here, we investigated using a porcine ARAS model, whether growth of ARAS AMSCs in hypoxia (Hx) versus normoxia (Nx) would enhance renal tissue repair, and comprehensively analyze how HPC modifies DNA hydroxymethylation compared to untreated ARAS and healthy/normal pigs (n=5 each). ARAS pigs exhibited elevated serum cholesterol, serum creatinine and renal artery stenosis, with a concomitant decrease in renal blood flow (RBF) and increased blood pressure (BP) compared to healthy pigs. Renal artery injection of either autologous Nx or Hx AMSCs improved diastolic BP, reduced kidney tissue fibrosis, and inflammation (CD3+ T-cells) in ARAS pigs. In addition, renal medullary hypoxia significantly lowered with Nx but not Hx AMSC treatment. Mechanistically, levels of epigenetic 5hmC marks (which reflect gene activation) estimated using DNA immunoprecipitation technique were elevated in profibrotic and inflammatory genes in ARAS compared with normal AMSCs. HPC significantly reduced 5hmC levels in cholesterol biosynthesis and oxidative stress response pathways in ARAS AMSCs. Thus, autologous AMSCs improve key renovascular parameters and inflammation in ARAS pigs, with HPC mitigating pathological molecular effects on inflammatory and profibrotic genes which may play a role in augmenting regenerative capacity of AMSCs.

Interventions for renal artery stenosis: Appraisal of novel physiological insights and procedural techniques to improve clinical outcome.

Randomized clinical trials failed to show additional benefit of renal artery stenting on top of medical therapy. Instead of writing an obituary on renal artery stenting, we try to explain these disappointing results. A transstenotic pressure gradient is needed to reduce renal perfusion and to activate the renin-angiotensin-aldosterone system. In only a minority of patients included in trials, a transstenotic pressure gradient is measured and reported. Like the coronary circulation, integration of physiological lesion assessment will allow to avoid stenting of non-significant lesions and select those patients that are most likely to benefit from renal artery stenting. Renal artery interventions are associated with peri-procedural complications. Contemporary techniques, including radial artery access, no-touch technique to engage the renal ostium and the use of embolic protection devices, will minimize procedural risk. Combining optimal patient selection and meticulous technique might lead to a netto clinical benefit when renal artery stenting is added to optimal medical therapy.

A new notable compression source of left renal vein entrapment: right renal artery.

PURPOSE: To estimate the incidences of left renal vein (LRV) entrapment by right renal artery (RRA), a phenomenon primarily reported as case reports. METHODS: The cross-sectional study consecutively screened renal vessel CT data of 38 (Renal) patients with nephropathy and 305 (Non-renal) patients with peripheral arterial diseases in a teaching hospital in northeast China between November 2018 and March 2023. The LRV compression by adjacent anatomical structures, including but not limited to RRA and multiple compression-related parameters, were investigated through multiplanar analysis of the CT data. RESULTS: The overall LRV entrapment rates by adjacent structures were 41.93% (12/31) and 24.00% (6/25), the rates of RRA-sourced LRV compression 22.58% (7/31) and 20.00% (5/25), and the rates of compression by superior mesenteric artery (SMA) 16.13% (5/31) and 4.00% (1/25) in the Renal and Non-renal groups, respectively, with no significance. The venous segments distal to the RRA-compressed site had a significantly larger transectional lumen area than those of the non-compressed veins in both groups (3.09 ± 1.29 vs. 1.82 ± 0.23, p < 0.001 and 4.30 ± 2.65 vs. 2.12 ± 0.55, p = 0.006; maximum-to-minimum area ratios in Renal and Non-renal groups, respectively). Nearly 80% of RRAs were found arising anteriorly rightwards instead of passing straight to the right. CONCLUSION: RRA-sourced LRV compression was not rare, and its incidence was higher than that of the compression by SMA in both patient cohorts. RRA could be a more common compression source than SMA concerning LRV entrapment. Further investigations involving different populations, including healthy individuals, are needed.

Ultrasound-guided renal artery balloon catheter occluded hybrid partial nephrectomy (UBo-HPN) with branch renal artery occlusion: a single arm trial.

BACKGROUND: One key focus of partial nephrectomy is preserving renal function. Segmental renal artery occlusion with microdissection at the renal hilum confines ischemia, effectively reducing warm ischemic injury. Ultrasound-Guided Renal Artery Balloon Catheter Occluded Hybrid Partial Nephrectomy (UBo-HPN) can achieve branch occlusion without the need for dissecting the renal hilum. OBJECTIVE: To investigate the feasibility and safety of UBo-HPN of branch renal artery occlusion in the treatment of localized renal tumors. SUBJECT AND METHODS: A prospective single-arm analysis involving 20 patients with renal localized tumors underwent robot assisted UBo-HPN with branch renal artery occlusion from August 2021 to July 2023, with an average follow-up of 12 months. RESULTS: All patient was successfully operated on without conversion to conventional arterial clamping or radical nephrectomy. One case (5%) of minor complication occurred in the whole cohort, which was bruising around the puncture site. The mean total operative time was 95.8 min, with a mean operative time of 21.25 min for vascular intervention. The mean warm ischemia time was 20.35 min, and the median estimated blood loss was 50 ml. The median eGFR preservation percentage at postoperative 48 h, 30 days, and the latest follow-up were 87.52%, 91.47%, and 92.2%, respectively. After a median follow-up of 10.2 (2.3-19.2) months, no patients had radiological tumor recurrence or died from tumor-related causes. CONCLUSIONS: UBo-HPN with renal artery branch occlusion emerges as an efficient alternative to partial nephrectomy (PN), which achieved branch artery occlusion without dissecting the renal hilum. Long-term follow-up is expected for functional outcomes.

An Anatomic Classification Scheme for Surgical Planning of Renal Artery Aneurysms.

PURPOSE: Renal artery aneurysm (RAA) is a rare disease. This study proposed and evaluated a new classification for RAA to assist in surgical decision-making. MATERIALS AND METHODS: Single-center data of 105 patients with RAAs from the vascular department of vascular surgery were collected retrospectively. A new classification scheme was proposed. Type I aneurysms arise from the main trunk, accessory branch, or first-order branches away from any bifurcation. Type II aneurysms arise from the first bifurcation with narrow necks (defined as dome-to-neck ratio >2) or from intralobular branches. Type III aneurysms with a wide neck arise from the first bifurcation and affect 2 or more branches that cannot be sacrificed without significant infarction of the kidney. RESULTS: There was 50 (47.62%) type I, 33 (31.43%) type II, and 22 (20.95%) type III aneurysms. The classification assigned endovascular repair as first-line treatment (for type I or II), while open techniques were conducted if anatomically suitable (for type III). A kappa level of 0.752 was achieved by the classification compared with a level of 0.579 from the classic Rundback classification. Technical primary success was achieved in 100% and 96.05%, and symptoms were completely resolved in 100% and 84.85%, while hypertension was relieved in 84.21% and 72.92% of patients receiving open surgery or endovascular repair, respectively. No significant difference was observed for perioperative or long-term complications among the 3 classification types. CONCLUSION: The new classification proved to be a convenient and effective method for facilitating choice of intervention for RAAs. CLINICAL IMPACT: This study proposed and evaluated a new classification scheme for renal artery aneurysms, which proved to be a convenient and effective method for facilitating surgical decision-making. Coil embolization was the first-line treatment if suitable, while aneurysm resection and reconstruction with vein graft were conducted for some complex lesions. The safety and efficacy of both open and endovascular methods were validated.

Antithrombotic Therapy and Freedom From Bridging Stent Occlusion After Elective Branched Endovascular Repair: A Multicenter International Cohort Study.

CLINICAL IMPACT: Based on our study, no antithrombotic therapy is significantly associated with bridging stent occlusion, and no evidence of the superiority of other antithrombotic therapy exists. Nevertehless, due to the low number of bridging stent occlusions, this study can neither support nor reject the PRINCE2SS recommendations. Further studies with larger cohorts are needed to determine clear guideliness of the best antithrombotic treatment regimen after complex enfovascular aortic repair.

Hybrid Stent Graft Technique in Bridging Hostile Renal Arteries in Thoracoabdominal Branched Endografting.

OBJECTIVE: Patency of target arteries is crucial for fenestrated and branched endovascular aortic repair (F/B-EVAR) in thoracoabdominal aortic aneurysms (TAAAs). Occlusions more frequently occur in renal arteries (RAs) than in coeliac and superior mesenteric arteries, especially in patients with hostile anatomy treated by BEVAR. This study aimed to report RA outcomes using a hybrid bridging stent graft technique with distal self expandable (SE) combined with proximal balloon expandable (BE) stent graft during BEVAR with hostile RA anatomies. METHODS: Clinical data from consecutive patients treated for TAAA by F/B-EVAR in three aortic centres (two in the USA, one in Europe) from 2016 to 2022 were prospectively collected. Renal artery orientation was defined as hostile in case of upward (type B) or downward + upward (type D) orientation. Hostile RAs accommodated by BEVAR and combination of SE + BE stent grafts were retrospectively evaluated. Intra-operative RA related complications, technical success, and branch occlusions were assessed as early outcomes. Primary and secondary RA patency, freedom from RA related re-interventions, and freedom from RA instability were assessed during follow up. RESULTS: Of 584 TAAAs managed by F/B-EVAR, 83 patients (14.2%) had 125 hostile RAs (type B, 45.6%; type D, 54.4%) managed by BEVAR with hybrid SE + BE stent grafts. Intra-operative complications occurred in three RAs (2.4%), including two dissections and one disconnection, all successfully managed with additional stent. Technical success was achieved in all cases, with no RA occlusions at 30 days. The median follow up was 21 (interquartile range 4, 38) months. Estimated three year RA primary patency was 97 ± 2%. Re-interventions were performed in five RAs (4.0%), including two RA branch embolisations for bleeding, two catheter thrombectomies with stent relining (bilateral occlusion in one patient), and one revision of type Ic endoleak. Freedom from RA related re-interventions and RA instability was 95 ± 2% and 91 ± 3% at three years, respectively. Renal artery secondary patency was 99 ± 1% at three years. CONCLUSION: In hostile RA anatomies, a combination of distal SE and proximal BE stent grafts as bridging stenting in BEVAR is safe and effective, with low rates of occlusion, re-interventions, and branch instability at midterm follow up.

Patterns of cortical oxygenation may predict the response to stenting in subjects with renal artery stenosis: A radiomics-based model.

BACKGROUND: Percutaneous-transluminal renal angioplasty (PTRA) and stenting aim to halt the progression of kidney disease in patients with renal artery stenosis (RAS), but its outcome is often suboptimal. We hypothesized that a model incorporating markers of renal function and oxygenation extracted using radiomics analysis of blood oxygenation-level dependent (BOLD)-MRI images may predict renal response to PTRA in swine RAS. MATERIALS AND METHODS: Twenty domestic pigs with RAS were scanned with CT and BOLD MRI before and 4 weeks after PTRA. Stenotic (STK) and contralateral (CLK) kidney volume, blood flow (RBF), and glomerular filtration rate (GFR) were determined, and BOLD-MRI R2 * maps were generated before and after administration of furosemide, a tubular reabsorption inhibitor. Radiomics features were extracted from pre-PTRA BOLD maps and Robust features were determined by Intraclass correlation coefficients (ICC). Prognostic models were developed to predict post-PTRA renal function based on the baseline functional and BOLD-radiomics features, using Lasso-regression for training, and testing with resampling. RESULTS: Twenty-six radiomics features passed the robustness test. STK oxygenation distribution pattern did not respond to furosemide, whereas in the CLK radiomics features sensitive to oxygenation heterogeneity declined. Radiomics-based model predictions of post-PTRA GFR (r = 0.58, p = 0.007) and RBF (r = 0.68; p = 0.001) correlated with actual measurements with sensitivity and specificity of 92% and 67%, respectively. Models were unsuccessful in predicting post-PTRA systemic measures of renal function. CONCLUSIONS: Several radiomics features are sensitive to cortical oxygenation patterns and permit estimation of post-PTRA renal function, thereby distinguishing subjects likely to respond to PTRA and stenting.

Risks and benefits of renal artery stenting in fibromuscular dysplasia: Lessons from the ARCADIA-POL study.

INTRODUCTION: Although renal stenting is the standard revascularization method for atherosclerotic renal artery stenosis (RAS) (FMD-RAS), stenting in fibromuscular dysplasia (FMD) RAS is usually limited to periprocedural complications of angioplasty and primary arterial dissection. The main aim of the study was to retrospectively analyze the immediate and long-term results of renal stenting versus angioplasty in patients with FMD. METHODS: Of 343 patients in the ARCADIA-POL registry, 58 patients underwent percutaneous treatment due to FMD-RAS (in 70 arteries). Percutaneous transluminal renal angioplasty (PTRA) was performed as an initial treatment in 61 arteries (PTRA-group), whereas primary stenting was undertaken in nine arteries (stent-group). Stent-related complications were defined as: in-stent restenosis > 50% (ISR); stent fracture; under-expansion; or migration. RESULTS: In the PTRA-group, the initial restenosis rate was 50.8%. A second procedure was then performed in 22 arteries: re-PTRA (12 arteries) or stenting (10 arteries). The incidence of recurrent restenosis after re-PTRA was 41.7%. Complications occurred in seven of 10 (70%) arteries secondarily treated by stenting: two with under-expansion and five with ISR. In the stent-group, stent under-expansion occurred in one case (11.1%) and ISR in three of nine stents (33.3%). In combined analysis of stented arteries, either primarily or secondarily, stent-related complications occurred in 11/19 stenting procedures (57.9%): three due to under-expansion and eight due to ISRs. Finally, despite several revascularization attempts, four of 19 (21%) stented arteries were totally occluded and one was significantly stenosed at follow-up imaging. CONCLUSION: Our study indicates that renal stenting in FMD-RAS may carry a high risk of late complications, including stent occlusion. Further observational data from large-scale registries are required.

Cerebral arteriopathies of childhood and stroke - A focus on systemic arteriopathies and pediatric fibromuscular dysplasia (FMD).

Systemic vascular involvement in children with cerebral arteriopathies is increasingly recognized and often highly morbid. Fibromuscular dysplasia (FMD) represents a cerebral arteriopathy with systemic involvement, commonly affecting the renal and carotid arteries. In adults, FMD diagnosis and classification typically relies on angiographic features, like the 'string-of-beads' appearance, following exclusion of other diseases. Pediatric FMD (pFMD) is considered equivalent to adult FMD although robust evidence for similarities is lacking. We conducted a comprehensive literature review on pFMD and revealed inherent differences between pediatric and adult-onset FMD across various domains including epidemiology, natural history, histopathophysiology, clinical, and radiological features. Although focal arterial lesions are often described in children with FMD, the radiological appearance of 'string-of-beads' is highly nonspecific in children. Furthermore, children predominantly exhibit intimal-type fibroplasia, common in other childhood monogenic arteriopathies. Our findings lend support to the notion that pFMD broadly reflects an undefined heterogenous group of monogenic systemic medium-or-large vessel steno-occlusive arteriopathies rather than a single entity. Recognizing the challenges in categorizing complex morphologies of cerebral arteriopathy using current classifications, we propose a novel term for describing children with cerebral and systemic vascular involvement: 'cerebral and systemic arteriopathy of childhood' (CSA-c). This term aims to streamline patient categorization and, when coupled with advanced vascular imaging and high-throughput genomics, will enhance our comprehension of etiology, and accelerate mechanism-targeted therapeutic developments. Lastly, in light of the high morbidity in children with cerebral and systemic arteriopathies, we suggest that investigating for systemic vascular involvement is important in children with cerebral arteriopathies.

Endovascular Treatment for Transplant Renal Artery Stenosis: 10 Years' Experience from a Single Center.

INTRODUCTION: Transplant renal artery stenosis (TRAS) is a common post-renal transplant complication. Although endovascular treatment is widely used to treat TRAS, previous research has been limited by small sample sizes. This article aimed to present the clinical outcomes of endovascular treatment for TRAS in a large sample. METHODS: Between January 2010 and December 2019, this study included patients with TRAS who were admitted to our center. All patients' clinical symptoms, comorbidities, imaging data, treatment, and follow-up results were reviewed retrospectively. RESULTS: Seventy two patients participated in this study. The median time between renal transplantation and TRAS was 5.25 months. Out of 72 patients, 55 (76.4%) received balloon dilatation in conjunction with stent deployment, 10 (13.9%) received drug-coated balloon dilatation alone, and 7 (9.7%) received balloon dilatation alone. The median follow-up period was 27 months. Primary patency rates were 100%, 81.8%, 74.5%, 64.6%, and 61.8% at 1, 3, 6, 12, and 24 months. A total of 23 patients were found to have restenosis during follow-up, with 6 (26.1%) requiring reintervention and none remaining restenosis after the second treatment. In the subgroup analysis of the three types of stenosis, patients with transplant renal stenosis at the anastomosis had a significantly higher rate of primary patency. Between endovascular treatments, the primary patency rate, postoperative creatinine clearance, and mean systolic blood pressure did not differ significantly. CONCLUSION: Endovascular treatment resulted in favorable short-term patency as well as effective relief of renal dysfunction and renal hypertension in TRAS patients.

A rare cause and an even rarer treatment of hypertension in a 5-year-old boy: Mid-aortic syndrome.

Renal artery stenosis is one of the common vascular diseases that cause hypertension in children. However, renal artery aneurysms and abdominal aortic aneurysms, which may be components of mid-aortic syndrome, are rarely associated with renal artery stenosis. Despite its rarity, early diagnosis and treatment are critical to prevent fatal complications. Currently, non-surgical invasive techniques are considered the first choice for treatment, but in some cases, surgery is inevitable. Here, we present a 5-year-old boy with a mid-aortic syndrome. The patient presented with a history of severe headache and epistaxis 5-6 times a day and was diagnosed with hypertension. A 9 × 9 mm saccular aneurysm on the anterior surface of the abdominal aorta at the level of the left renal artery ostium, and a 12 mm aneurysm in the left renal artery after a stenotic segment at the hilum level was detected in the doppler USG and contrast-enhanced imaging techniques. The patient was operated on electively. We used a PTFE patch to repair the abdominal aorta and, saphenous vein which was taken from his father to repair the renal artery. The patient recovered well and was discharged on the 18th day.

Severe hypertension in tuberous sclerosis complex caused by renal artery stenosis: A case report.

Tuberous sclerosis complex (TSC) is a rare autosomal dominant neurocutaneous disease. Arterial hypertension is one of its uncommon complications, which is supposed to be caused by renal cysts or angiomyolipomas. Few studies have been reported in the literature on renal artery stenosis (RAS) as the cause of hypertension in TSC. Hence, we reported a boy who presented with uncontrolled hypertension under five anti-hypertension drugs and was diagnosed with TSC complicated with left RAS. His high blood pressure was relieved by percutaneous transluminal renal angioplasty (PTRA). In one and a half years follow-up, his blood pressure was normal whilst he took four anti-hypertensive drugs. In conclusion, children with TCS complicated with hypertension should be carefully screened for RAS, which might be relieved by percutaneous balloon dilatation.

Clinical Practice Report of Contrast-Enhanced Ultrasound in Renal Artery Disease.

OBJECTIVES: To evaluate the diagnostic performance of renal artery contrast-enhanced ultrasound (CEUS) with modified inspection section and summarize subsequent changes in imaging assessment of renal artery disease. METHODS: A total of 1015 patients underwent renal artery CEUS were included in the study. Among them, 79 patients (156 renal arteries) suspected with renal artery stenosis (RAS) underwent digital subtraction angiography (DSA) subsequently. DSA was used as the gold standard to evaluate the diagnostic performance of CEUS in detecting RAS (≥30%) and severe stenosis (≥70%), as well as the diagnostic accuracy of classification of stenosis degree. Besides, 127 of the 1015 patients underwent other imaging examinations such as computed tomography angiography (CTA) or magnetic resonance angiography (MRA) after CEUS and annual proportion of these imaging examinations was assessed. RESULTS: The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of CEUS for detecting RAS (≥30%) was 96.4%, 88.6%, 94.2%, 95.6% and 90.7%, respectively and the kappa value was .857 (P < .01). CEUS had a good performance in distinguishing severe stenosis (≥70%) with a sensitivity of 91.1%, specificity of 95.5%, accuracy of 92.9%, PPV of 96.5%, NPV of 88.7% and the kappa value was 0.857(P < .01). There was no significant difference between CEUS and DSA in detecting stenosis (P = 1.0) and severe stenosis (P = .227). The diagnostic accuracy of CEUS in grading RAS was 85.3% and the kappa value was 0.753 (P < .01). Besides, the annual proportion of other imaging examinations decreased for 4 consecutive years. CONCLUSIONS: CEUS is a non-invasive, safe and valuable technique for the assessment of renal artery disease and worthy of promotion.

Doppler Ultrasound of the Renal Vasculature.

Ultrasound is the first-line imaging modality used in patients with suspected renovascular disease. Common indications include renovascular hypertension and unexplained renal dysfunction. We review the ultrasound imaging findings of various pathologies involving the renal vessels, including the renal arteries (atherosclerotic stenosis, fibromuscular dysplasia, dissection, arteriovenous fistula, and aneurysm) and veins (tumor and bland thrombus as well as vascular compression syndromes). The current role of renal artery stent placement for atherosclerotic stenosis is also discussed.

Renal artery occlusion in a young woman - a tale of mysterious thrombosis.

BACKGROUND: Renal artery thrombosis is rare and limited reports exist in the young population. The most common aetiology is thromboembolic disease or abdominal trauma in this population and isolated occurrences are extremely rare. We present the case of an 18-year-old woman with spontaneous unilateral renal artery thrombosis and infarction for whom reperfusion was achieved through endovascular intervention. The aetiology of her thrombosis remains unclear and is under investigation with differential diagnoses being fibromuscular dysplasia, large and medium vessel vasculitis, and thromboembolic causes. OBJECTIVE: To demonstrate the value in attempting salvage of an ischaemic kidney in a young patient with an unexplained spontaneous renal thrombosis. METHOD: JM is an 18-year-old woman who presented to a large regional tertiary hospital with 3 days of right flank pain. She had no infective symptoms and no urinary or bowel changes before admission. She was not pregnant, and her only medication was the oral contraceptive pill commenced 3 months prior. A CT angiogram demonstrated right renal artery thrombosis with renal infarction. The kidney was deemed potentially salvageable, and ultrasound defined adequate vessel calibre to access for thrombectomy in the context of a negative coagulopathy screen. RESULTS: The patient underwent thrombolysis, thrombectomy and balloon angioplasty. Intraoperatively, a thin segment of distal stenosis was identified, and angiogram reperfusion was achieved with subsequent improvement in renal function. CONCLUSION: Renal artery thrombosis in young people is extremely rare and presents a diagnostic and management challenge requiring input from multiple teams including nephrology, rheumatology, paediatrics and vascular surgery. Systemic coagulopathy and vasculitis are differentials against anatomical aetiologies such as fibromuscular dysplasia. Our case adds to the limited literature regarding this in the young population. Renal artery thrombosis with occlusion in young people is very rare and is most often associated with a systemic coagulopathic disorder, such as antiphospholipid syndrome or structural pathology of the renal vasculature such as fibromuscular dysplasia. The work-up of a young female presenting with renal artery thrombosis without any previous medical history screens for a wide range of pathological processes.