3D printing: a useful tool for safe clinical practice in children with complex vasculature.

BACKGROUND: 3D printing has been used in different medical contexts, although it is underutilised in paediatrics. We present the first use of 3D printing in the management of three paediatric patients with complex renovascular disease. METHODS: Patient-specific 3D models were produced from conventional 2D imaging and manufactured using 3D polyjet printing technology. All three patients had different underlying pathologies, but all underwent multiple endovascular interventions (renal artery balloon angioplasty) prior to 3D printing and subsequent vascular surgery. The models were verified by an expert radiologist and then presented to the multidisciplinary team to aid with surgical planning. RESULTS: Following evaluation of the 3D-printed models, all patients underwent successful uni/bilateral renal auto-transplants and aortic bypass surgery. The 3D models allowed more detailed preoperative discussions and more focused planning of surgical approach, therefore enhancing safer surgical planning. It influenced clinical decision-making and shortened general anaesthetic time. The families and the patients reported that they had a significantly improved understanding of the patient's condition and had more confidence in understanding proposed surgical intervention, thereby contributing to obtaining good-quality informed consent. CONCLUSION: 3D printing has a great potential to improve both surgical safety and decision-making as well as patient understanding in the field of paediatrics and may be considered in wider surgical areas.

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.

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.

Open bypass revascularisation for endovascular-resistant transplant renal artery stenosis secondary to mechanical renal artery kinking.

Transplant renal artery stenosis (TRAS) represents a significant vascular complication subsequent to renal transplantation. This pathology is associated with grave implications including graft dysfunction and mortality. Early identification and therapeutical intervention are imperative for preserving graft longevity and achieving optimal clinical outcomes. We detail the case of a male in his 20s, following renal transplantation, who encountered recurrent TRAS, aetiologically linked to mechanical arterial kinking. Initial management using endovascular techniques yielded insufficient resolution. Consequently, the persistence of endovascular-resistant stenosis necessitated a surgical bypass intervention using the great saphenous vein, granting a 2-year period devoid of restenosis. The existing literature emphasises the indispensability of discerning the appropriate juncture for transitioning from endovascular to surgical management in TRAS cases. The robustness and durability of bypass grafts present an efficacious therapeutical strategy in contemporaneous practice.

Renal Autotransplantation for Uncontrolled Hypertension in Nonatherosclerotic Renal Artery Stenosis-2 Case Reports and a Brief Review of the Literature.

Fibromuscular dysplasia is the most common cause of renovascular hypertension in young adults under 40 years old. It is potentially amenable to renal artery angioplasty, which frequently normalizes blood pressure. However, limited options exist if angioplasty is not technically possible, or restenosis occurs. Here, we describe 2 patients who presented with hypertension secondary to renal artery stenosis. In the first case, a young adult with hypertension secondary to renal artery stenosis (fibromuscular dysplasia), developed restenosis 11 weeks after an initially successful renal artery angioplasty. In the second case, a patient with neurofibromatosis type 1 was diagnosed with hypertension secondary to renal artery stenosis. Angioplasty was not possible due to multiple branch occlusions. Both individuals went on to have successful renal autotransplantations, which ultimately cured their hypertension. In this article, we review the background, indications, and blood pressure outcomes in relation to renal autotransplantation in nonatherosclerotic renal artery stenosis.

A Case Report of Concurrent Transplant Renal Artery Stenosis, Renal Cell Carcinoma, and Papillary Thyroid Cancer After Renal Transplantation: A Literature Review.

BACKGROUND: Kidney transplantation is the preferred treatment option for eligible patients with end-stage renal disease. With advanced transplantation technology and novel immunosuppressive agents, kidney transplant recipients survive significantly longer. However, the chance of developing malignant tumors has increased, posing a serious challenge to the survival of transplanted kidneys and patients. CASE PRESENTATION: We report a male patient (the patient's informed consent has been obtained) who underwent kidney transplantation 23 years ago. Subsequently, he developed transplant renal artery stenosis, primary renal clear cell carcinoma, and papillary thyroid cancer. The narrowed blood vessels were dilated through percutaneous transluminal angioplasty, and the malignant tumor was removed surgically. Currently, antirejection drugs are regularly taken, and the transplanted kidney function is good. The patient is satisfied with his living conditions. CONCLUSIONS: Hypertension that is difficult to control after kidney transplantation should be suspected as a possibility of graft vascular stenosis. When B-ultrasound cannot accurately diagnose it, magnetic resonance angiography should be used as early as possible to clarify the diagnosis and relieve the stenosis before graft dysfunction. Transplantation patients have a high incidence of malignant tumors after surgery, and the risk increases with the prolongation of the disease course. The focus should be on symptomatic treatment of related diseases, and antirejection drugs can be reduced or not reduced as appropriate.

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.

Endovascular treatments of atherosclerotic renovascular disease: a narrative review and literature search.

In recent years, endovascular treatments have become more common in patients with renal artery stenosis and aneurysm. Although the treatment algorithms are not universally accepted, endovascular therapy can be readily utilized for the appropriate indications in the context of surgical treatment for renovascular diseases. The most important factor to consider is that the correct indication is applied for such treatment. Although the applied procedures are believed to have minimal risk, any complications that occur may result in major problems. Moreover, the pathology that is being treated (e.g., hypertension, high serum creatinine concentration, or low glomerular filtration rate) must be well defined. As stent and balloon technologies continue to be developed, more positive results are expected in the coming years. In the present study, we reviewed the endovascular treatment algorithms for atherosclerotic renovascular disease and performed a narrative review of the current literature.

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.

Atherosclerotic renovascular disease.

This review investigates patients with renovascular disease due to atherosclerotic renal artery stenosis. This group of patients has a very high risk of cardiovascular events. Randomised trials have failed to show that renal artery stenting is more effective than medical therapy alone in most patients but did not enroll patients with high-risk clinical syndromes. Recent cohort studies have observed a beneficial effect of renal artery stenting on blood pressure and kidney function in high-risk patients with atherosclerotic renovascular disease. Therefore, a Danish randomised trial has been initiated to explore these observations further.

Updated trends in percutaneous renal arteriography among radiologists and other specialties.

PURPOSE: Prior studies have demonstrated an overall decline in percutaneous renal artery angioplasty with and without stenting from 1988 to 2009. We evaluated the recent utilization trends in percutaneous renal arteriography (PTRA) among radiologists and non-radiologist providers from 2010 to 2018. METHODS: Data from the 2010-2018 nationwide Medicare Part B fee-for-service database were used to tabulate case volumes for PTRA. Annual utilization rates per 10,000 Medicare beneficiaries were calculated and aggregated based on physician specialty: radiologists, cardiologists, vascular surgeons, general surgeons, or others. RESULTS: From 2010 to 2018, the overall utilization rate of PTRA markedly declined (-72% change; from 15.5 to 4.3 cases per 10,000 Medicare beneficiaries). Proportionally, the cardiologist share of PTRA saw the greatest decline, falling from 74% market share in 2010 (11.4/15.5 cases) to only 36% market share in 2018 (1.6/4.3 cases). The market share of PTRA performed by radiologists grew from 12% market share in 2010 (1.9/15.5 cases) to 28% in 2018 (1.2/4.3 cases); despite this, the absolute number of PTRA performed by radiologists saw a smaller decline over this period (-34%; 1.9 to 1.2 cases). CONCLUSION: The total utilization rates of PTRA in the Medicare population has continued to decline from 2010 to 2018, likely due to clinical trials suggesting limited efficacy of angioplasty and stenting in the treatment of renovascular hypertension and other factors such as declining reimbursement. The overall and per-specialty rates continue to decline, reflecting an overarching trend away from procedural management of renovascular hypertension.

[Effect of renal artery stenting on the clinical and geriatric status of elderly patients with vasorenal hypertension.]

The study consists in determining the effect of renal artery stenting in patients with arterial hypertension in combination with renal artery stenosis on the dynamics of clinical and geriatric status in terms of such indicators as the number of drugs taken, cognitive status, determined by the MMSE scale, prevalence of the frequency of falls, psycho-emotional status by the Beck scale, the quality of sleep on the VAS scale, the index of age discrimination according to the E.Palmore ageism questionnaire, the quality of life according to the SF 36 questionnaire. The study involved 72 elderly patients with arterial hypertension in combination with renal artery stenosis. According to the results of the study, as a result of stenting of the renal arteries, there is a decrease in the number of drugs taken, an improvement in the cognitive status on the MMSE scale, a decrease in the frequency of falls, an improvement in the psycho-emotional status on the Beck scale, an improvement in the quality of sleep on the VAS scale, a decrease in the level of age discrimination, an increase in the quality of life according to questionnaire SF-36 on all scales.

[An Unusual Complication in 3 Cases: Renal��Subcapsular Hematoma Following Percutaneous Angioplasty]. / ���� Olguda Nadir Bir Komplikasyon: Perk��tan Anjioplasti Sonras�� Renal Subkaps��ler Hematom.

Renal artery stenosis is the leading cause of secondary hypertension. Percutaneous treatment options are safe and e���ective but can, in rare cases, entail possible complications such as renal subcapsular hematoma. Awareness of such complications will enable better management. Although post-intervention subcapsular hematomas are believed to occur secondary to wire perforation, in this report, we present 3 cases demonstrating reperfusion injury ���ndings rather than wire perforation.

The impact of renal artery stenting on therapeutic aims.

Renal artery stenosis manifests as poorly-controlled hypertension, impaired renal function or pulmonary oedema, therefore the success of treatment is dependent on indication. This study aims to determine the outcomes of patients undergoing renal artery stenting (RASt) based on therapeutic aim compared to criteria used in the largest randomised trial. Retrospective case-note review of patients undergoing RASt between 2008-2021 (n = 74). The cohort was stratified by indication for intervention (renal dysfunction, hypertension, pulmonary oedema) and criteria employed in the CORAL trial, with outcomes and adverse consequences reported. Intervention for hypertension achieved significant reduction in systolic blood pressure and antihypertensive agents at 1 year (median 43 mmHg, 1 drug), without detrimental impact on renal function. Intervention for renal dysfunction reduced serum creatinine by a median 124 µmol/L, sustained after 6 months. Intervention for pulmonary oedema was universally successful with significant reduction in SBP and serum creatinine sustained at 1 year. Patients who would have been excluded from the CORAL trial achieved greater reduction in serum creatinine than patients meeting the inclusion criteria, with equivalent blood pressure reduction. There were 2 procedure-related mortalities and 5 procedural complications requiring further intervention. 5 patients had reduction in renal function following intervention and 7 failed to achieve the intended therapeutic benefit. Renal artery stenting is effective in treating the indication for which it has been performed. Previous trials may have underestimated the clinical benefits by analysis of a heterogenous population undergoing a procedure rather than considering the indication, and excluding patients who would maximally benefit.

Percutaneous revascularization for atherosclerotic renal artery stenosis: a meta-analysis.

OBJECTIVE: This study investigates whether medication therapy alone is as effective and safe as percutaneous revascularization (PR) in patients with atherosclerotic renal artery stenosis (ARAS). MATERIALS AND METHODS: The Embase, PubMed, and Cochrane Library databases were searched from their inception to July 31, 2021, for randomized controlled trials (RCTs) reporting PR for ARAS. RevMan 5.3 was employed to analyze the retrieved articles. RESULTS: Eight studies with a total of 2,225 ARAS patients were included in this analysis, demonstrating that PR and medication therapy alone had a similar effect on both systolic [mean difference (MD)= 0.19, 95% CI: -1.64- 2.02] and diastolic blood pressure (MD= -0.44, 95% CI: -1.68-0.80). Meanwhile, there were no differences in all-cause mortality [Odds ratio (OR) = 0.89, 95% CI: 0.70-1.14], stroke (OR = 0.84, 95% CI: 0.55-1.31), congestive heart failure (OR = 0.89, 95% CI: 0.67-1.19), and perioperative complications (OR = 0.87, 95% CI: 0.68-1.12). CONCLUSIONS: Medication therapy alone is as effective and safe as PR.

Renal Artery Stenosis due to Entrapment.

BACKGROUND: Common etiologies of renovascular occlusive disease include atherosclerosis disease, developmental fibrotic conditions such as fibromuscular dysplasia, and vasculitis. Extrinsic compression of the renal artery is a rarely reported phenomenon but can lead to similar clinical manifestations. METHODS: We report recent experience with 2 patients who presented with extrinsic renal artery compression due to entrapment. Diagnosis was made with a constellation of findings on computed tomography angiography, dynamic duplex sonography, and catheter angiography. Both patients had hypertension and 1 had downstream subsegmental renal infarcts. The patients, both with right-sided renal artery entrapment, were treated with open surgical decompression. Exposure was achieved via extended Kocher maneuver followed by mobilization of the right kidney and, in 1 patient, detachment of the right lobe of liver to allow circumferential exposure of the proximal right renal artery to the aorta. All entrapping tissue was circumferentially released. RESULTS: Both operations were uncomplicated. Intraoperative sonography was used to confirm luminal patency of the released segments. Follow-up of renal artery duplex in both patients demonstrated resolution of dynamic compression. Renal artery peak systolic velocity and accelerations indices were all within normal limits. In both patients, improvement in blood pressure control was noted and discontinuation of anticoagulation was possible in the patient who had recurrent episodes of renal infarct. CONCLUSIONS: Extrinsic compression of renal artery by diaphragmatic crura is rare but should be considered in younger patients or otherwise any patients with no vascular risk factors when renovascular hypertension workup yields no demonstrable intrinsic disease. A high index of suspicion should be raised when an anomalously high origin of the renal artery or proximity to the diaphragmatic crura is seen on cross-sectional imaging. Work-up should include dynamic imaging to assess compression of renal arteries during expiration. Open surgical or laparoscopic decompression of the involved renal arteries can be curative.

Percutaneous cutting balloon angioplasty for the treatment of renovascular hypertension in children and adolescents.

OBJECTIVE: Percutaneous transluminal renal angioplasty (PTRA), the recommended treatment in children with renovascular hypertension (RVH), often has unsatisfactory outcomes. Cutting balloons may improve the results of angioplasty in different vascular beds with complex and resistant lesions. We retrospectively analysed the effects of percutaneous cutting balloon angioplasty (PCBA) on blood pressure, cardiac mass and renal artery acceleration time in children/adolescents referred to our centre for RVH. PATIENTS AND METHODS: Thirteen patients (aged 9-19 years) with renal artery stenosis (RAS) and severe hypertension were identified. RASs were focal fibromuscular (FMD) or FMD-like dysplasia (in six cases bilateral, in five associated with mid aortic syndrome). Ten patients had uncontrolled hypertension, in nine cases associated with left ventricular hypertrophy (LVH). Acceleration time was abnormal in all stenotic arteries. Eighteen PCBA were performed, in three arteries associated with stent implantation. RESULTS: PCBA was technically successful in all individuals without major complications. In one patient, an intra-stent restenosis occurred, successfully redilated with conventional angioplasty without recurrence at 4 years distance. One year after PCBA, mean SBP and DBPs were markedly reduced from 146 ±â€Š25 to 121 ±â€Š10 mmHg and from 87 ±â€Š11 to 65 ±â€Š12 mmHg, respectively ( P  < 0.001 for both). At that time, hypertension was cured in seven children and controlled in five individuals. This favourable outcome was confirmed with ambulatory blood pressure measurement in four patients. At the latest follow-up, left ventricular mass and acceleration time were normal in all patients. CONCLUSION: PCBA proved to be a well tolerated and effective procedure that can be considered as an alternative to PTRA to treat hypertensive children/adolescents with recurrent or resistant RAS.

Perfusion and oxygenation in allografts with transplant renal artery stenosis: Evaluation with functional magnetic resonance imaging.

BACKGROUND: Transplant renal artery stenosis (TRAS) has been shown to reduce kidney perfusion leading to post-operative hypertension. We aimed to measure the perfusion and oxygenation changes in TRAS with arterial spin labeling (ASL) and blood oxygen level-dependent (BOLD) imaging, respectively. METHODS: In this single-center prospective study, a total of seven patients with TRAS and seven age- and sex-matched normal kidney transplant recipients underwent both ASL and BOLD imaging. Moreover, measurements of ASL and BOLD were also performed in five patients after successful angioplasty for TRAS. RESULTS: Allograft cortical perfusion as measured by ASL in the TRAS group was significantly decreased as compared with normal control group (129.9 ± 46.6 ml/100 g vs. 202.4 ± 47.7 ml/100 g, P = .01). Interestingly, allograft oxygenation as indicated by R2* derived from BOLD in both the cortex (16.42 ± 1.90 Hz vs. 18.25 ± 4.34 Hz, P = .33) and the medulla (30.34 ± 2.35 Hz vs. 30.43 ± 6.85 Hz, P = .97) showed no statistical difference between the TRAS and normal control group. In addition, both cortical and medullary oxygenation remained unchanged despite significantly improved cortical perfusion in those undergone successful angioplasty. CONCLUSION: Cortical and medullary oxygenation were preserved in the presence of reduced allograft perfusion in clinically significant TRAS. Prospective larger studies are needed to conclusively establish perfusion and oxygenation changes in TRAS.

Shockwave lithotripsy for treatment of calcific renal artery stenosis after an inadequately expanded renal artery stent.

Renal artery calcifications can be associated with insufficient stent expansion and in-stent restenosis. Intravascular lithotripsy (IVL) uses shockwaves to disrupt calcium and treat calcific renal in-stent restenosis. Herein, the authors present a case to treat resistant reno-vascular hypertension and in-stent restenosis of an inadequately expanded renal stent in a patient with severe calcific renal artery stenosis. The patient was treated with IVL and stent dilation. The patient was followed subsequently, and her home blood pressure was well controlled on anti-hypertensive medications. In conclusion, IVL promises pronounced success in the modification of severely calcified renal artery lesions and can be used to treat renal artery stenosis even in the context of inadequately expanding renal artery stents.

Extensive calcifications can contribute to the blockages of the arteries of the kidney. These can be associated with insufficient stent expansion in patients undergoing stent placement. Intravascular lithotripsy uses high-energy shockwaves to disrupt calcium deposits of renal arteries. Herein, the authors present a case of high blood pressure refractory to four blood pressure medications associated with blockage of previously placed stent of the artery of the left kidney. This case demonstrates that lithotripsy is an effective procedure to modify calcifications in order to facilitate expansion of the stent to restore blood flow to kidneys.