Bilateral renal artery revascularisation in heart failure.

Renal artery stenosis can complicate the management of heart failure with reduced ejection fraction, as it is a conventional contraindication to the use of ACE inhibitors. We report a case in which bilateral renal artery revascularisation allowed the safe reintroduction of enalapril (and subsequently sacubitril valsartan) in a patient with severe left ventricular systolic dysfunction. There is a role for renal artery angioplasty in selected patients to allow optimal medical therapy for patients with heart failure due to impaired systolic function.

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.

Endovascular treatment of renal artery stenosis in Germany: a retrospective analysis of the DEGIR registry 2018-2021.

PURPOSE: To provide an overview of endovascular treatment of renal artery stenosis (RAS) using the data of the Deutsche Gesellschaft für interventionelle Radiologie (DeGIR) quality management system. MATERIALS AND METHODS: A retrospective analysis was performed. Pre-, peri- and postprocedural data, technical success rates, complication rates, and clinical success rates at dismissal were examined. RESULTS: Between 2018 and 2021, 2134 angiography examinations of the renal arteries were performed: diagnostic angiography in 70 patients (3 %), balloon angioplasty in 795 (37 %), stent implantation in 1166 (55 %) and miscellaneous procedures in 103 (5 %). The lesion length was less than or equal to 5 mm in 1837 patients (87 %), between 5 and 10 mm in 197 (9 %), and between 10 and 20 mm in 62 (3 %). The degree of stenosis was less than 50 % in 156 patients (7 %), greater than 50 % in 239 (11 %), and greater than 70 % in 1472 (70 %). Occlusion was treated in 235 patients (11 %). Symptoms at discharge resolved in 600 patients (29 %), improved in 1012 (49 %), were unchanged in 77 (4 %), and worsened in 5 (0.2 %). Complications were reported in 51 patients (2.5 %) and the mortality rate was 0.15 %. CONCLUSION: A substantial number of patients with RAS and occlusions were treated by radiologists in Germany, with high technical success rates and low complication rates. The indication should be determined carefully as the current European guidelines for the treatment of RAS suggest that only carefully selected groups of patients will benefit from recanalizing treatment. KEY POINTS: · Carefully selected patient groups may benefit from endovascular treatment of renal artery stenosis.. · Analysis of the DEGIR quality management database shows that treatment of renal artery stenosis was performed by radiologists in Germany with high technical success rates and low complication rates.. · Recanalization even led to symptom improvement in a large proportion of patients with occlusions..

A Rare Case of Focal Renal Fibromuscular Dysplasia Treated With Angioplasty: A Case Report.

BACKGROUND: Fibromuscular dysplasia is an idiopathic, segmental, nonatherosclerotic, noninflammatory vascular disease that can lead to arterial stenosis, tortuosity, occlusion, aneurysms, and dissection. Fibromuscular dysplasia is a rare cause of hypertension that can easily be missed. To date, there has been no definitive treatment for fibromuscular dysplasia. CASE REPORT: In this report, we present an uncommon case of renovascular hypertension in a 21-year-old non-white female with a 3-year history of hypertension secondary to fibromuscular dysplasia involving bilateral renal arteries. Computed tomography angiography during the arterial phase revealed distal focal narrowing of the right main renal artery, distal focal narrowing of the left main renal artery, and proximal focal narrowing of the left accessory lower renal artery. Percutaneous balloon dilatation of the stenotic lesion was performed successfully up to 1 year After the procedure, the arterial blood pressure was within the normal range (110/70 to 125/75 mmHg) without medication. After 1 year of follow-up, CTA revealed re-stenosis in left main renal artery without clinical symptoms and normal blood pressure. Repeated procedure was done successfully. CONCLUSIONS: This case report highlights the difficulty in the diagnosis and treatment of focal fibromuscular dysplasia in young non-white female patients. Computerized tomographic angiography is a useful tool for identifying the cause and showing the benefit of percutaneous transluminal renal angioplasty treatment for this rare entity, as an early percutaneous angioplasty intervention may have a clinical cure for hypertension.

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.

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.

Renal artery stenosis stenting with unmasking and embolisation of a renal arteriovenous fistula.

A man in his 70s was presented to the emergency department with uncontrollable hypertension and worsening renal function on a background of atherosclerosis-related bilateral renal artery stenosis. Following progressive deterioration in renal function and refractory hypertension, the patient was referred to interventional radiology for consideration of renal artery stenting. Following stenting of the right renal artery, a large renal arteriovenous fistula became apparent, which required emergent embolisation. Both procedures were successful, with excellent clinical and radiological responses.

Drug-coated balloon for treatment of non-atherosclerotic renal artery stenosis-a multi-center study.

INTRODUCTION: Renal artery stenosis (RAS) is a significant reason for secondary hypertension. Impaired renal function and subsequent cardiopulmonary dysfunction could also occur. Patients of non-atherosclerotic RAS has a relatively young age and long life expectancy. Revascularization with percutaneous transluminal angioplasty (PTA) is a viable treatment option. However, restenosis is unavoidable which limits its use. Drug-coated balloon (DCB) has been proven to be effective in restenosis prevention in femoropopliteal arterial diseases and in patients with renal artery stenosis. And PTA for Renal artery fibromuscular dysplasia is safe and clinically successful. Therefore, we could speculate that DCB might have potential efficacy in non-atherosclerotic RAS treatment. METHODS AND ANALYSIS: This will be a randomized multi-center-controlled trial. Eighty-four eligible participants will be assigned randomly in a 1:1 ratio to the control group (plain old balloon, POB) and the experimental group (DCB). Subjects in the former group will receive balloon dilatation alone, and in the latter group will undergo the DCB angioplasty. The DCB used in this study will be a paclitaxel-coated balloon (Orchid, Acotec Scientific Holdings Limited, Beijing, China). Follow-up visits will be scheduled 1, 3, 6, 9, and 12 months after the intervention. Primary outcomes will include controlled blood pressure and primary patency in the 9-month follow-up. Secondary outcomes will include technical success rate, complication rate, and bail-out stenting rate. TRIAL REGISTRATION: ClinicalTrials.gov (number NCT05858190). Protocol version V.4 (3 May 2023).

The Effect of Endovascular Treatment of Renal Artery Stenoses on Coexistent Aneurysms Associated with Fibromuscular Dysplasia.

PURPOSE: Endovascular data on patients with coexistent renal artery stenosis (RAS) and renal artery aneurysm (RAA) caused by fibromuscular dysplasia (FMD) are scarce, and the outcomes from RAS-specific treatment on RAA remain unclear. This study aimed to evaluate the safety and effectiveness of RAS-specific endovascular management in patients with coexisting RAA caused by FMD. MATERIALS AND METHODS: Clinical and endovascular data on 19 patients with coexistent RAS and RAA caused by FMD who underwent RAS-specific endovascular therapy were analyzed prospectively. An RAA located within 10 mm of the RAS was defined as a stenosis-related RAA (SRAA), and long-term outcomes were evaluated. RESULTS: Nineteen patients (24 RASs and 30 RAAs) underwent endovascular therapy. Twenty-one RASs were treated with balloon angioplasty alone, whereas 3 RASs were treated with stent implantation. None of the RAAs were treated directly. During an average of 4.2 years ± 3.2 of follow-up, systolic and diastolic blood pressures decreased from 183.0 mm Hg ± 19.5 and 120.2 mm Hg ± 19.0 to 127.9 mm Hg ± 10.3 and 80.9 mm Hg ± 6.9, respectively; the number of antihypertensive medications reduced from 1.7 ± 1.0 to 0.8 ± 0.3 (for all, P < .001). The serum creatinine level remained stable. The maximum diameter of all RAAs decreased from 14.6 mm ± 9.7 to 11.3 mm ± 8.4 (P < .001). There was a significant difference in the improvement rate of the maximum diameter between SRAAs (65.0%, 13 of 20) and non-SRAAs (20.0%, 2 of 10) (P = .019). CONCLUSIONS: RAS-specific endovascular therapy is safe and effective and possibly aids in preventing RAA progression in patients with FMD with coexistent RAS and RAA.

Atherosclerotic renovascular disease: a clinical practice document by the European Renal Best Practice (ERBP) board of the European Renal Association (ERA) and the Working Group Hypertension and the Kidney of the European Society of Hypertension (ESH).

Atherosclerotic renovascular disease (ARVD) is the most common type of renal artery stenosis. It represents a common health problem with clinical presentations relevant to many medical specialties and carries a high risk for future cardiovascular and renal events, as well as overall mortality. The available evidence regarding the management of ARVD is conflicting. Randomized controlled trials failed to demonstrate superiority of percutaneous transluminal renal artery angioplasty (PTRA) with or without stenting in addition to standard medical therapy compared with medical therapy alone in lowering blood pressure levels or preventing adverse renal and cardiovascular outcomes in patients with ARVD, but they carried several limitations and met important criticism. Observational studies showed that PTRA is associated with future cardiorenal benefits in patients presenting with high-risk ARVD phenotypes (i.e. flash pulmonary oedema, resistant hypertension or rapid loss of kidney function). This clinical practice document, prepared by experts from the European Renal Best Practice (ERBP) board of the European Renal Association (ERA) and from the Working Group on Hypertension and the Kidney of the European Society of Hypertension (ESH), summarizes current knowledge in epidemiology, pathophysiology and diagnostic assessment of ARVD and presents, following a systematic literature review, key evidence relevant to treatment, with an aim to support clinicians in decision making and everyday management of patients with this condition.

Endovascular Treatment of Transplant Renal Artery Stenosis: A Single-Center Retrospective Cohort Study.

OBJECTIVES: Endovascular therapy is the most common treatment for transplant renal artery stenosis; however, its long-term outcomes remain controversial, with no uniform standard for percutaneous transluminal angioplasty versus percutaneous transluminal stenting. MATERIALS AND METHODS: We retrospectively analyzed 26 patients with transplant renal artery stenosis who underwent endovascular therapy. We evaluated long-term efficacy of endovascular therapy and the reasonable choice of treatment. RESULTS: Serum creatinine increased significantly at onset of transplant renal artery stenosis (113.88 ± 37.573 before vs 279.31 ± 94.98 µmol/L during stenosis; P1 < .001), and endovascular therapy had a good short-term effect (279.31 ± 94.98 during stenosis vs 139.54 ± 124.40 µmol/L at 2 weeks posttreatment; P2 = .002). Long-term efficacy of endovascular therapy was stable (139.54 ± 124.40 at 2 weeks posttreatment vs 150.69 ± 180.72 at 6 months vs 161.58 ± 174.49 µmol/L at last follow-up; P3 > .05). Blood pressure increased significantly at onset of transplant renal artery stenosis (126.65 ± 16.11 before vs 159.62 ± 25.84 mm Hg during stenosis; P1 < .001). Moreover, the short-term effect of endovascular therapy was good (159.62 ± 25.84 during stenosis vs 128.73 ± 14.22 mm Hg at 2 weeks posttreatment; P2 < .001). Long-term effects remained stable (128.73 ± 14.22 at 2 weeks posttreatment vs 131.15 ± 14.55 at 6 months vs 138.50 ± 16.82 mm Hg at last follow-up; P3 > .05). Peak systolic velocity decreased significantly after endovascular therapy (176.6 ± 67.93 during stenosis vs 114.24 ± 67.93 cm/s at 2 weeks posttreatment; P < .001). CONCLUSIONS: Endovascular therapy is effective in transplant renal artery stenosis treatment and has a low incidence of complications. Percutaneous transluminal angioplasty should be performed routinely during endovascular therapy. After dilation, if stenosis remains >25% or retracted, then percutaneous transluminal stenting is recommended. Otherwise, percutaneous transluminal angioplasty is preferred.

Endovascular Versus Medical Management of Atherosclerotic Renovascular Disease: Update and Emerging Concepts.

Atherosclerotic renovascular disease is the most frequent cause of renovascular hypertension and its prevalence increases with age and in specific subset of patients, such as those with end-stage chronic kidney disease, heart failure, and coronary artery disease. Besides hypertension, atherosclerotic renovascular disease is responsible for several clinical manifestations, including life-threatening conditions, such as recurrent flash pulmonary edema, rapidly progressive chronic kidney disease, or acute kidney injury. Atherosclerotic renovascular disease is usually part of a more diffuse atherosclerotic process and requires a combination therapy including antihypertensive, antiplatelet and lipid-lowering agents, as well as optimization of antidiabetic treatment, if needed. Besides medical therapy, percutaneous renal angioplasty was supposed to be the most effective therapy for atherosclerotic renovascular disease, by leading to blood flow restoration. However, despite an apparently solid rationale, several randomized clinical trials failed to confirm the favorable effects of percutaneous renal angioplasty on blood pressure control, kidney function, cardiovascular and renal outcomes, previously reported in observational, retrospective and single-center cohorts, switching off the enthusiasm for this procedure. Several studies' limitations may partly account for this failure, including heterogeneity of diagnostic techniques, overestimation of the degree of renal artery stenosis, inappropriate timing of revascularization, multiple protocol revisions, frequent crossovers, and most importantly exclusion of patients at higher likelihood to respond to angioplasty. The purpose of this review is to summarize studies' potential weaknesses and provide guidance to the clinician for identification of patients who may benefit most from revascularization.

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.

Usefulness of selective percutaneous transluminal angioplasty using renal echo for a patient with bilateral renal artery stenosis and chronic renal failure.

A man in his 70s visited the hospital for chronic kidney disease with hypertension. He had anuria for several days before visiting the hospital. His creatinine level rose to 8.97 mg/dL (from 3 mg/dL) and his systemic blood pressure increased to 183 mm Hg. Other uraemic symptoms were also observed, and he was therefore admitted to the hospital and started continuous haemodiafiltration. MRI and angiography showed a highly stenotic lesion with calcification at the origin of the renal artery; a CT scan showed atrophy of the left kidney. Renal Doppler ultrasonography was performed and renal resistive indexes were: 0.92 for the left kidney and 0.68 for the right kidney. The viability of the right kidney was thought to be maintained, and percutaneous transluminal renal angioplasty (PTRA) for the right renal artery stenosis was performed; his creatinine level improved (3 mg/dL) and his systolic blood pressure decreased (120 mm Hg). We implanted a stent on the right stenotic lesion and the right renal artery blood flow improved. We experienced an effective PTRA for the right renal artery for bilateral renal artery stenosis. Although the indications of PTRA for renal artery stenosis are limited, the evaluation of renal function using ultrasonography could be a useful index for determining the culprit lesion.

Utilizing the balloon anchoring technique to improve device deliverability during stent revascularization for atherosclerotic renal artery stenosis.

INTRODUCTION: The stent revascularization for severely calcified renal artery lesions can be challenging, due to a deficiency in back-up force provided by the guide catheter. The aim of this report is to describe the use of the balloon anchoring technique to increase device maneuverability and deliverability after the failure of conventional renal artery revascularization. TECHNICAL NOTE: This technique was adopted in a patient with subtotal occlusive and severely calcified lesion in the proximal portion of the right main renal artery. Two guidewires were separately introduced into the proximal side branch (SB) and main branch (MB) of the renal artery. Anchor balloon inflated at low pressure in SB, anchoring the MB-wire and the guide catheter, thus giving us the ability to cross the tight calcified proximal cap of the MB lesion with a non-compliant balloon. After performing pre-dilatations and retrieving the anchor balloon, we implanted a balloon-expandable stent and achieved optimal final angiographic results. CONCLUSIONS: The balloon anchoring technique can improve device maneuverability and deliverability during various catheterization procedures. Our report firstly demonstrates how to perform the balloon anchoring technique in renal angioplasty treatment and then explains its effectiveness in revascularization of the renal artery with challenging anatomies.

"Coexistence of IgA nephropathy and renal artery stenosis in Takayasu arteritis: case report and literature review".

Although Takayasu arteritis (TAK) is a form of large vessel vasculitis, complications of glomerulonephritis have occasionally been observed, with mesangial proliferative glomerulonephritis as the most common. The aim of this work was to present a case-based review regarding the association of glomerulonephritis and IgA nephropathy (IgAN) with TAK. A literature search was carried out using the PubMed and Scopus databases for articles published in English, and the Ichu-shi Web for Japanese. A 34-year-old Japanese man was evaluated for proteinuria, and IgAN was diagnosed by renal biopsy. Simultaneously, aortic wall thickening and right renal artery stenosis confirmed a coexisting TAK. Prednisolone and methotrexate improved both diseases, and percutaneous transluminal renal angioplasty resulted in right renal artery reopening. Our case and literature review revealed that membranous proliferative glomerulonephritis and IgAN are common in eastern Asia, while focal segmental glomerulosclerosis and mesangial proliferative glomerulonephritis are common in other regions. The incidence of IgAN is higher in TAK cases and is mostly reported in Asia. Abdominal aortic involvement and renal artery stenosis are common in cases with preceding TAK. IgAN could be related to the cytokine network involving interleukin-6, suggesting the usefulness of tocilizumab in patients with TAK accompanied by IgAN. The type of glomerulonephritis complicated with TAK differs among regions, and patients with TAK are more likely to experience IgAN than the healthy population.

Long-term outcomes of angioplasty for pediatric renovascular hypertension: A single-center experience.

OBJECTIVES: We used single-center data to evaluate the long-term outcome of percutaneous transluminal angioplasty (PTA) for pediatric renovascular hypertension (RVH) and to analyze the factors that influence effectiveness. METHODS: We retrospectively evaluated 33 pediatric RVH patients (18 boys; mean age: 9.1 ± 4 years, range: 2-16) who underwent PTA from January 2007 to December 2019. 15 patients had Takayasu arteritis (TA) and 18 were non-TA. The median follow-up from the initial PTA was 69 months (range: 12-157; IQR: 25.5-89). RESULTS: The technical success rate of 52 PTA procedures was 90.4% in 33 children. Renal artery stents were implanted in two patients, external guidewires were used in two patients, and a drug-coated balloon was used in only one patient. The overall effective rate of PTA was 63.6%, including cured 39.4% and improved 24.2%, at the end of follow-up. Overall clinical outcomes were not statistically different between the TA and non-TA groups (p = 0.316), nor were cure rates (p = 0.072). 15 patients received reintervention due to restenosis after the first successful PTA; the interval was 2-56 months (median: 12 months). Four patients received reintervention due to a failed PTA. A total of four patients received open surgery. Binary logistics regression analysis showed that stenosis length and residual stenosis rate were strongly correlated with effective PTA (p = 0.045, p = 0.044). CONCLUSIONS: As a primary treatment for pediatric RVH, PTA can achieve satisfactory results, which are influenced by lesion length and residual stenosis rate.

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.

Use of Intravascular Lithotripsy in Heavily Calcified Renal Artery Stenosis: A Case Report.

Heavily calcified arterial lesions are difficult to treat in an endovascular manner with conventional techniques due to limited arterial compliance. Intravascular lithotripsy offers a novel minimally invasive therapeutic option through endovascular emission of acoustic waves, fracturing calcium deposits and facilitating lesion dilation. We present the case of a successful application of the Shockwave intravascular lithotripsy system (IVL®, Shockwave Medical Inc) in a heavily calcified stenosis of the right renal artery in a patient with a coral reef aorta.