Cutting Balloon Angioplasty in Children with Resistant Renal Artery Stenosis

Pediatric Transplant Interventions

The field of pediatric organ transplantation has grown significantly in recent decades, with interventional radiology (IR) playing an essential role in managing pre and post-transplant complications. Pediatric transplant patients face unique challenges compared to adults, including donor-recipient size mismatch, and complications of a growing child with changing physiology. Interventional radiologists play a major role in pediatric renal and liver transplant. IR interventions begin early in the child's pretransplant journey, with diagnostic procedures such as biopsies, angiograms, and cholangiograms. These procedures are essential for understanding the etiology of organ failure and identifying potential transplant candidates. Minimally invasive therapeutic procedures may serve as bridges to transplant and may include vascular access optimization for hemodialysis, transjugular intrahepatic portosystemic shunts (TIPS) creation, and tumor embolization or ablation. After transplant, image-guided biopsies for the surveillance of graft rejection and treatment of vascular or luminal stenoses, pseudoaneurysms, and anastomotic leaks can maintain the function and longevity of the transplant organ. Careful consideration must be given to patient size and evolving anatomy, radiation exposure, and the need for deeper sedation for pediatric patients. Despite these challenges, the integration of IR in pediatric transplant care has proven beneficial, offering minimally invasive alternatives to surgery, faster recovery times, and improved outcomes.

Pediatric Renovascular Hypertension: A Pediatric Interventional Radiologist's Perspective

Renovascular hypertension (RVH) contributes close to one-fourth of the secondary etiologies of hypertension in children and a delay in diagnosis can result in adverse clinical outcomes. RVH in children is clinically silent with elevations in blood pressure measurements sometimes as its sole manifestation. Only a high index of suspicion by the clinician can prompt its detection. Despite the availability of other imaging modalities like ultrasound, computed tomography, and magnetic resonance imaging, digital subtraction angiography is still considered the gold standard to make a diagnosis of RVH. Angioplasty is considered the treatment of choice in appropriately selected patients. In this article, we shall focus on the various imaging findings, and management of RVH in children, which requires a multidisciplinary approach with a special focus on the role of interventional radiology.

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 ± 25 to 121 ± 10 mmHg and from 87 ± 11 to 65 ± 12 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.

Renovascular hypertension in pediatric patients: update on diagnosis and management

Renovascular hypertension (RVH) is defined as an elevated blood pressure caused by kidney hypoperfusion, generally as a result of anatomic stenosis of the renal artery with consequent activation of the Renin Angiotensin-Aldosterone System. The main causes include genetic and inflammatory disorders, extrinsic compression, and idiopathic alterations. RVH is often asymptomatic and should be suspected in any child with refractory hypertension, especially if other suggestive findings are present, including those with severe hypertension, abdominal bruit, and abrupt fall of glomerular filtration rate after administration of angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers. There is a consensus that digital subtraction angiography is the gold standard method for the diagnosis of RVH. Nevertheless, the role of non-invasive imaging studies such as Doppler ultrasound, magnetic resonance angiography, or computed tomographic angiography remains controversial, especially due to limited pediatric evidence. The therapeutic approach should be individualized, and management options include non-surgical pharmacological therapy and revascularization with percutaneous transluminal renal angioplasty (PTRA) or surgery. The prognosis is related to the procedure performed, and PTRA has a higher restenosis rate compared to surgery, although a decreased risk of complications. This review summarizes the causes, physiopathology, diagnosis, treatment, and prognosis of RVH in pediatric patients. Further studies are required to define the best approach for RVH in children.

Hypertension in Children and Adolescents with Turner Syndrome (TS), Neurofibromatosis 1 (NF1), and Williams Syndrome (WS)

PURPOSE OF REVIEW

Turner syndrome (TS), neurofibromatosis type 1(NF1), and William Syndrome (WS) are 3 genetic conditions that are all associated with a substantial increase in risk of hypertension. In this review, we focus on factors leading to hypertension and on clinical manifestations and management of hypertension in children and adolescents with these genetic conditions RECENT FINDINGS: In most instances, hypertension is secondary. There is a high prevalence of masked hypertension in TS; however, the extent to which control of the BP helps reduce the risk of aortic dissection/aneurysm in TS is not yet fully elucidated. Vasculopathies are the least emphasized but most important manifestation of NF1. Of note, routine screening for pheochromocytoma in NFI is not recommended as it is not cost-effective. Cardiovascular complications are the major cause of death in patients with WBS. ABPM identifies patients without overt aortic or renovascular narrowing. Antihypertensive agents such as ARBs that have direct vascular wall effects and agents that inhibit oxidative stress (minoxidil) should be considered, even in those who do not exhibit overt hypertension. Elevated blood pressure in children and adolescence manifests early with end-organ changes and when left untreated, increases risk for premature onset of cardiovascular disease. Vigilant monitoring of the blood pressure is recommended. Accurate early diagnosis and management of hypertension will delay or prevent target organ damage and ensure a healthier transition to adulthood among children afflicted with these conditions.

Renovascular hypertension in children

Paediatric hypertension, defined as systolic blood pressure > 95th percentile for age, sex and height is often incidentally diagnosed. Renovascular hypertension (RVH) is responsible for 5-25% of hypertension in children. Renal artery stenosis and middle aortic syndrome can both can be associated with various conditions such as fibromuscular dysplasia, Williams syndrome & Neurofibromatosis type 1. This paper discusses the approaches to diagnosis and interventional management and outcomes of renovascular hypertension in children. Angiography is considered the gold standard in establishing the diagnosis of renovascular disease in children. Angioplasty is beneficial in the majority of patients and generally repeated angioplasty is considered more appropriate than stenting. Surgical options should first be considered before placing a stent unless there is an emergent requirement. Given the established safety and success of endovascular intervention, at most institutions it remains the preferred treatment option.

Treatment of Renal Artery Stenosis in a Solitary Kidney Using Cutting Balloon Angioplasty in a Paediatric Patient

Aims:

Renovascular hypertension is a rare cause of paediatric hypertension. It is however, a potentially treatable cause particularly when caused by renal artery stenosis (RAS).

Materials and Methods:

We present the case of an 11-month-old girl presenting with cardiac dysfunction. She was found to be hypertensive with a systolic blood pressure >180mmHg. DMSA demonstrated a small right kidney and a divided renal function of 6% on the right and 94% on the left. Spectral analysis demonstrated abnormal waveforms suggestive of RAS of the left kidney.

Results:

Angioplasty with a cutting balloon was successful. Blood pressure measurements, renal function and left ventricular function improved.

Conclusion:

RAS can be successfully treated with cutting balloon angioplasty after failure of convention balloon angioplasty to relieve the narrowing. In our case, there was an immediate successful angiographic result that on mid-term follow-up demonstrated significant improvement in clinical and biochemical outcomes and cessation of all anti-hypertensive medication.

Cutting Balloon Angioplasty (CBA) for the Treatment of Renal Artery Fibromuscular Dysplasia (FMD) in Six Patients: 5-Year Long-Term Results

PURPOSE

To evaluate long-term outcomes in terms of hypertension control, recurrent stenosis, and reinterventions from patients who underwent cutting balloon angioplasty (CBA) for symptomatic renal artery fibromuscular dysplasia (FMD).

MATERIALS AND METHODS

From 2011, six consecutive renal artery FMD women underwent CBA for poorly controlled hypertension, despite antihypertensive therapy. Follow-up consisted of blood pressure monitoring and duplex ultrasonography at 1, 6, and 12 months and thereafter annually for 5 years.

RESULTS

All treatments were technically successful. Recurrence of hypertension was found in two patients within 12 months, and reinterventions were performed using CBA.

CONCLUSION

Results show the efficacy of CBA for renal artery FMD.

Successful cutting balloon angioplasty in a child with resistant renal artery stenosis

Background

Although renovascular hypertension is a rare disease, it is associated with 5–10 % of cases of childhood hypertension. It is a potentially treatable cause of hypertension, and is often caused by renal artery stenosis (RAS). The most common cause of RAS in children is fibromuscular dysplasia (FMD). The options for treating RAS depend on the location, severity and abnormality underlying the condition.

Case presentation

A previously healthy 7-year-old Korean boy presented to our clinic with hypertension and headache. Renal ultrasonography and multi-detector computed tomography (MDCT) showed severe focal stenosis at the middle portion of the left renal artery (LRA) and multiple collateral vessels. Percutaneous balloon angioplasty was performed as an initial treatment, but yielded unsatisfactory results. The presence of intimal-type FMD was suspected based on his clinical features, angiographic appearance, and resistance to percutaneous transluminal renal angioplasty. Thereafter, his blood pressure was normalized using antihypertensive medication. Follow-up multi-detector computed tomography at 11 years of age showed persistent severe stenosis of the LRA. After unsuccessful attempts to perform balloon angioplasty, 3.5-mm cutting balloon angioplasty (CBA) was performed and yielded satisfactory results. He was discharged without any medication. At 1 year and 6 months after the intervention, he has been normotensive and had not required any antihypertensive medication.

Conclusion

The author describes a case of resistant RAS that was detected on MDCT and successfully treated using percutaneous (CBA). Although cutting balloon angioplasty is useful in many clinical conditions, including the current case, clinicians should carefully consider the associated risk of arterial disruption and pseudoaneurysm formation.

European consensus on the diagnosis and management of fibromuscular dysplasia

The main objectives of this expert consensus are to raise awareness about fibromuscular dysplasia, which is more frequent and more often systemic than previously thought and can sometimes have devastating consequences; to provide up-to-date recommendations for the diagnosis, evaluation, and management of the disease; and to identify research priorities. The emphasis has been put on recommendations for daily practice. The main topics covered include definition, classification, diagnosis, and management of fibromuscular dysplasia in adult patients with symptomatic involvement of the renal arteries, supra-aortic trunks, and digestive and peripheral arteries.

Angioplasty for renovascular hypertension in 78 children

OBJECTIVES

To evaluate the outcome of percutaneous transluminal angioplasty (PTA) in children with renovascular hypertension (RVH) treated at a single centre over 29 years.

METHODS

A retrospective study of the medical charts of all children with RVH who underwent PTA between 1984 and 2012. The primary outcome measurement was blood pressure (BP) achieved after the procedure. The BP before the procedure was compared with that at last available follow-up, 6 (range 0.6-16) years after the initial procedure.

RESULTS

Seventy-eight children with median (range) age of 6.5 (0.5-17) years were studied. Twenty-three (29.5%) had an underlying syndrome, 35 (44.9%) children had bilateral renal artery stenosis (RAS), 18 (23%) intrarenal disease and 11(14%) showed bilateral RAS and intrarenal disease. Twenty (25.6%) children had mid-aortic syndrome and 14 (17.9%) cerebrovascular disease. One hundred and fourteen PTA procedures were carried out including 31 stent insertions. Following PTA, BP was improved in 49 (62.8%) children and of those 18 (23.1%) were cured. Children with involvement of only the main renal arteries showed improved BP control in 79.9% of the children with cure in 39.5%. BP was intentionally maintained above the 95th centile for age and height in four children with coexistent cerebrovascular disease. No change in BP was seen in 18 children despite observed technical success of the PTA, and in seven children due to technical failure of the procedure.

CONCLUSIONS

PTA provided a clinical benefit in 62.8% of children with RVH.

Diagnostic and medical strategy for renovascular hypertension: report from a monocentric pediatric cohort

Renovascular hypertension accounts for 5-10 % of hypertension cases in children; there is currently no consensus on treatment. Here, we report on our clinical experience with this disease and outline the different pathways in which to investigate it. We report retrospectively on ten children diagnosed with renovascular hypertension at the University Hospital of Nantes from 2001 to 2012. The main findings were obtained by fortuitous screening of children aged 2 months to 14 years old with neurofibromatosis (n = 2) and fibromuscular dysplasia (n = 8). The hypertension was always severe yet asymptomatic. Lesions were complicated in nine out of ten cases and included bilateral, multiple, mid-aortic syndrome and aneurysm. Doppler ultrasound associated with computed tomography allowed for a precise diagnosis in seven out of ten cases. Where ambiguities persisted, they were highlighted by arteriography, the gold standard investigation. Medical treatment was insufficient, leading to invasive procedures in nine out of ten children: 2 nephrectomies, 2 autotransplantations, and 21 repetitive percutaneous transluminal angioplasties. After invasive procedures, blood pressure control improved in four cases and was resolved in three.

CONCLUSION

Arteriography remains to be the gold standard technique for renovascular hypertension in children and can be combined with angioplasty when medical treatment is rendered obsolete. The role of computed tomography is controversial. Despite the heterogeneity of the children studied, we present a general medical and therapeutic management pathway for the treatment of this disease.

Aortic bypass and bilateral renal autotransplantation for mid-aortic syndrome

BACKGROUND

Middle aortic syndrome (MAS) is a rare condition characterized by stenosis of the proximal abdominal aorta and the origin of the renal and digestive arteries. When medical therapy and interventional radiology fail to control threatening reno-vascular arterial hypertension (AHT), surgery is required and may need several interventions, which are usually delayed until late childhood.

CASE

We report on a 3-year-old girl with severe AHT (180/130 mmHg) caused by MAS. There was no evidence of generalized vascular disease or complications of AHT. AHT failed to respond to medical therapy (five drugs), endovascular dilatation, and stenting was considered unfeasible due to the complex multiple strictures. Surgery consisted of: explantation of the two kidneys; aortic bypass between the lower thoracic and lower abdominal aorta using a prosthetic graft; reimplantation of the kidneys onto the normal iliac arteries. The post-operative course was uneventful. Owing to recurrent stenosis of the re-implanted renal arteries, endoluminal dilatations were performed 4 and 5 months after surgery. Two years after surgery, the child is alive and well, off anti-hypertensive therapy, with normal blood pressure.

CONCLUSION

Mild aortic syndrome can be treated with a one-stage surgical repair with aorto-aortic bypass and bilateral auto-transplantation, even in young children.

Renal autotransplantation for the treatment of renovascular hypertension in the pediatric population

PURPOSE

To evaluate the effectiveness of renal autotransplantation (RA) for the treatment of renovascular hypertension (RVH) in a selected group of children in whom medical care, a percutaneous transluminal angioplasty or vascular reconstruction failed or was technically impossible, in addition to the short-term and long-term morbidity.

MATERIALS AND METHODS

A retrospective case review of 13 pediatric patients with severe or complicated RVH who underwent RA between May 1993 and August 2008 was conducted. We defined blood pressure (BP) response as follows: Cured: normal BP values with no need of antihypertensive medication (AM); Improved: normal BP values with AM requirements; Failed: abnormal BP values despite treatment with AM.

RESULTS

16 RA were performed in 7 female and 6 male patients. Bilateral RA were performed in 2 females and in 1 male. The average age at consultation for hypertension was 8.5 years (range 4-12 years) and the time of transplantation was 9.12 years (range 6-13 years). Etiological diagnoses were: Takayasu disease (n = 5); renal artery fibrodysplasia (n = 3); mid-aortic syndrome (n = 3) and neurofibromatosis type I (n = 2). Results after RA were: Cured: 61.5%; Improved: 38.5%. No patient presented therapeutic failure during follow up time (median = 53.4 months). Only 1 case presented a postoperative complication.

CONCLUSIONS

RA is a procedure with no mortality and low morbidity rates that renders very satisfactory therapeutic results in the pediatric population.

Spectrum of renal findings in pediatric fibromuscular dysplasia and neurofibromatosis type 1

BACKGROUND

Fibromuscular dysplasia (FMD) and neurofibromatosis type 1 (NF1) are the most common causes of pediatric renal artery stenosis (RAS) in western countries, and characterization of their angiographic features could aid in an accurate diagnosis and in treatment.

OBJECTIVE

This study characterizes renal angiographic findings in pediatric fibromuscular dysplasia (FMD) and neurofibromatosis type 1(NF1).

MATERIALS AND METHODS

We reviewed 68 angiograms performed over 11 years on 43 children with renovascular hypertension (20 male, 23 females; ages 1 month to -19 years; median/average 9.8 years). Ten patients were diagnosed with NF1, and 33 had presumed FMD. The frequency, extent and distribution of lesions were determined and analyzed.

RESULTS

Stenosis was found in 91% of patients (n=39/43), with 86% showing stenosis of 1st or 2nd order arteries, and 12% distal to 2nd order. Stenoses in multiple 1st/2nd order arteries were found in 32% of patients, and 36/43 patients had 1-2 stenoses. The most common lesion was a ≤ 5 mm stenosis in a 1st/2nd order artery, in 42%. Mean percentage of stenosis in a 1st/2nd order vessel was 62%; ≥ 70% stenosis was found in 53%, and ≥ 90% stenosis in 29%. Bilateral disease was noted in 30% of patients. Intraparenchymal disease, distal to 2nd order branches, was seen in 30%. Aneurysms were seen in 28%, beading in 19% and collaterals in 51% (associated with ≥ 70% stenosis). Mid-aortic narrowing was seen in 16%, more often in patients with NF1.

CONCLUSION

We provide a descriptive characterization of renal angiographic findings in pediatric FMD and NF1.

[State of the art: interventional radiology management of renovascular hypertension]

The management of renal artery stenosis (RAS) has been the subject of numerous clinical studies and recommendations, most frequently with regards to atherosclerotic RAS. We present the current recommendations from the French Society of Cardiac and Vascular Imaging updated from a recent literature review (April 2008) with regards to medical, endovascular and surgical management of atheroscletotic and non-atherosclerotic RAS. The evidence-based recommendations are ranked by level.

Renal artery rupture following cutting balloon angioplasty for fibromuscular dysplasia: a case report

Introduction

Angioplasty with the use of cutting balloons has been suggested by some case reports and small series for the treatment of renal artery stenoses that are resistant to conventional balloon catheters. Based on this limited experience, the use of this technology has been suggested as safe. Herein, we report a renal artery rupture following angioplasty with a cutting balloon. The complication was salvaged with a stent graft.

Case presentation

A 30-year-old white female patient with resistant hypertension caused by a severe renal artery stenosis attributed to fibromuscular dysplasia, was submitted to conventional balloon angioplasty without success. Dilatation of the lesion with a cutting balloon resulted in arterial rupture, with concomitant retroperitoneal hematoma.

Conclusion

Cutting balloon angioplasty of renal artery lesions resistant to conventional balloon angioplasty should not be considered as safe as previously thought. When proceeding with such a procedure, a stent graft should be available for immediate use.

Renal artery rupture following cutting balloon angioplasty for fibromuscular dysplasia: a case report

INTRODUCTION

Angioplasty with the use of cutting balloons has been suggested by some case reports and small series for the treatment of renal artery stenoses that are resistant to conventional balloon catheters. Based on this limited experience, the use of this technology has been suggested as safe. Herein, we report a renal artery rupture following angioplasty with a cutting balloon. The complication was salvaged with a stent graft.

CASE PRESENTATION

A 30-year-old white female patient with resistant hypertension caused by a severe renal artery stenosis attributed to fibromuscular dysplasia, was submitted to conventional balloon angioplasty without success. Dilatation of the lesion with a cutting balloon resulted in arterial rupture, with concomitant retroperitoneal hematoma.

CONCLUSION

Cutting balloon angioplasty of renal artery lesions resistant to conventional balloon angioplasty should not be considered as safe as previously thought. When proceeding with such a procedure, a stent graft should be available for immediate use.

Cutting balloon angioplasty of bilateral renal artery stenosis due to Takayasu arteritis in a 5-year-old child with midterm follow-up

The aim of this report is to demonstrate the successful endovascular treatment of bilateral renal artery stenosis due to Takayasu arteritis by cutting balloon angioplasty in a 5-year-old child with mid-term follow-up.

Restoration of failed renal graft function after successful angioplasty of pressure-resistant renal artery stenosis using a cutting balloon: a case report

This study is the report of a 37-year-old male with a transplanted kidney from a 3.5-year-old donor: the graft had two arteries transplanted with an aortic patch to an external iliac artery. Four months after transplantation, the graft function deteriorated, together with the development of hypertension. Stenosis of both graft arteries was detected and the patient was referred for angioplasty. The angiographic result was suboptimal, nevertheless, the graft function improved and was more or less stable (serum creatinine, 160-200 micromol/l) for 4 years, along with persistently difficult-to-control hypertension. Five years after transplantation, the graft function deteriorated again and severe graft artery restenosis was detected. The restenosis did not respond to dilatation, graft function failed, hypertension decompensated, and left ventricular failure developed. The patient required dialysis. A cutting balloon angioplasty opened the artery, and kidney function was restored after a few days: the serum creatinine level dropped to 140-160 micromol/l, and the glomerular filtration rate (creatinine clearance) to 0.65 ml/min/1.73 m(2). The graft function has now been stable for more than 2 years, however, the hypertension is still difficult to control.

Renovascular hypertension in children

Renovascular disease is an uncommon but important cause of hypertension in children. It is usually diagnosed after a long delay because blood pressure is infrequently measured in children and high values are generally dismissed as inaccurate. Many children with renovascular disease have abnormalities of other blood vessels (aorta, cerebral, intestinal, or iliac). Individuals suspected of having the disorder can be investigated further with CT, MRI, or renal scintigraphy done before and after administration of an angiotensin-converting-enzyme inhibitor, but angiography is still the gold standard. Most children with renovascular disease will need interventional or surgical treatment. Endovascular treatment with or without stenting will cure or reduce high blood pressure in more than half of all affected children. Surgical intervention, if needed, should be delayed preferably until an age when the child is fully grown. Modern treatment provided by a multidisciplinary team of paediatric nephrologists, interventional radiologists, and vascular surgeons offers good long-term treatment results.