Angioplasty for renovascular hypertension in children: 20-year experience

Successful emergency renal auto-transplantation in a child with renovascular disease

Renal artery occlusion is a rare but potentially catastrophic complication of paediatric endovascular renal artery intervention. Emergency auto-transplantation may be required to salvage the kidney; to date this has only been described in adults. We report our experience of performing emergency kidney auto-transplantation following acute renal artery thrombosis in a child undergoing redo renal artery angioplasty A 20-month-old boy presented with refractory hypertension and hypertensive cardiomyopathy secondary to multifocal fibromuscular dysplasia (FMD) with a single functioning kidney. Acute thrombosis of the renal artery during redo-endovascular balloon angioplasty necessitated emergency renal auto-transplantation. Subsequent acute kidney injury was reversible with benefit to renal function in the medium-term despite prolonged warm ischaemic time of two hours. We recommend that high-risk patients undergoing renal artery intervention do so at centres with on-site renal and vascular surgical backup.

Renal Artery Stenosis and Mid-Aortic Syndrome in Children-A Review

Background: Renal artery stenosis (RAS) and mid-aortic syndrome (MAS) are significant yet under-recognized causes of pediatric hypertension. RAS is characterized by the narrowing of the renal arteries, while MAS involves the stenosis of the abdominal aorta along with its associated vessels. The etiologies of RAS and MAS often involve genetic factors and acquired conditions such as fibromuscular dysplasia and Takayasu arteritis, contributing to their complex clinical presentations. Despite advancements in diagnostic imaging, challenges remain in effectively identifying these conditions. Pharmacological treatment can achieve partial blood pressure control, but it usually does not lead to complete recovery. Treatment options range from angioplasty to more definitive surgical interventions such as renal artery reimplantation and aorto-aortic bypass, tailored according to the specific pathology and extent of the disease. Methods: This review explores the diagnosis and management of RAS and MAS in children, highlighting the necessity for early detection and showcasing the evolving landscape of treatment. Conclusions: We advocate for a multidisciplinary approach that includes advanced imaging for effective diagnosis and tailored therapy. By integrating the latest research and clinical practices, this article provides valuable insights into managing complex vascular conditions in the pediatric population, ultimately aiming to enhance the quality of life for affected individuals.

Percutaneous Transluminal Renal Angioplasty for Pediatric Hypertension Secondary to Total Renal Artery Occlusion

PURPOSE

To assess the feasibility and effectiveness of percutaneous transluminal renal angioplasty (PTRA) for pediatric renovascular hypertension (RVH) secondary to total renal artery occlusion (RAO).

MATERIALS AND METHODS

From 2011 to 2021, 13 pediatric patients with RVH confirmed with 14 renal artery occlusions were reviewed. The mean age was 11.2 years (range, 4-16 years). Nine occlusions involved main artery occlusion, and 5 involved branch occlusion. Blood pressure ratio (BPR) was defined as the ratio of the actual measured blood pressure (BP) value to the 95th percentile value adjusted for age, sex, and height.

RESULTS

PTRA was performed in 9 patients (9/13, 69%). Technical success was achieved in 5 patients (5/9, 56%), with stent placement in 2 children (2/9, 22%). During the 12-month follow-up, restenosis was identified in both of the stent-receiving patients at the 12-month follow-up visit (2/9, 22%). Mean systolic BPR decreased from 1.20 (SD ± 0.07) to 0.96 (SD ± 0.06; P = .003), mean diastolic BPR decreased from 1.19 (SD ± 0.07) to 0.95 (SD ± 0.08; P = .005), and the number of medications required decreased from 3.8 (SD ± 0.8) to 2.4 (SD ± 0.9; P = .052) after PTRA. Subsequent to PTRA, the mean glomerular filtration rate of the occluded kidney improved from 19.5 mL/min (SD ± 12.3) to 36.3 mL/min (SD ± 10.8; P = .007), and the mean longitudinal dimension of the affected kidneys significantly increased from 8.2 cm (SD ± 1.5) to 9.2 cm (SD ± 1.7; P = .006).

CONCLUSIONS

Endovascular treatment is often feasible for pediatric patients with RAO, results in acceptable BP control, and preserves renal function.

Cardiovascular outcomes improve in children with renovascular hypertension following endovascular and surgical interventions

BACKGROUND

Renovascular hypertension (RenoVH) is a cause of hypertension in children. A common cause of RenoVH is renal artery stenosis which acts by reducing blood supply to renal parenchyma and activating the renin-angiotensin-aldosterone axis, often leading to cardiac remodelling. This longitudinal observational study aims to describe occurrence of cardiovascular changes secondary to RenoVH and also any improvement in cardiac remodelling after successful endovascular and/or surgical intervention.

METHODS

All patients with RenoVH referred to our centre, who received ≥ 1 endovascular intervention (some had also undergone surgical interventions) were included. Data were collected by retrospective database review over a 22-year period. We assessed oscillometric blood pressure and eight echocardiographic parameters pre- and post-intervention.

RESULTS

One hundred fifty-two patients met inclusion criteria and had on average two endovascular interventions; of these children, six presented in heart failure. Blood pressure (BP) control was achieved by 54.4% of patients post-intervention. Average z-scores improved in interventricular septal thickness in diastole (IVSD), posterior Wall thickness in diastole (PWD) and fractional shortening (FS); left ventricular mass index (LVMI) and relative wall thickness (RWT) also improved. PWD saw the greatest reduction in mean difference in children with abnormal (z-score reduction 0.25, p < 0.001) and severely abnormal (z-score reduction 0.23, p < 0.001) z-scores between pre- and post-intervention echocardiograms. Almost half (45.9%) had reduction in prescribed antihypertensive medications, and 21.3% could discontinue all antihypertensive therapy.

CONCLUSIONS

Our study reports improvement in cardiac outcomes after endovascular + / - surgical interventions. This is evidenced by BP control, and echocardiogram changes in which almost half achieved normalisation in systolic BP readings and reduction in the number of children with abnormal echocardiographic parameters. A higher resolution version of the Graphical abstract is available as Supplementary information.

SUPPLEMENTARY INFORMATION

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.

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.

Role of drug-eluting stent on Takayasu arteritis with renal artery stenosis

Takayasu arteritis (TA) is defined as granulomatous inflammation of large arteries involving the aorta and its primary branches. Takayasu arteritis with renal artery stenosis (TARAS) is a common cause of pediatric renovascular hypertension. The main purposes of TARAS management are to improve high blood pressure and recover renal function. When general medication fails to improve symptoms, renal revascularization may be attempted.  Implantation of a drug-eluting stent (DES) has been used as an alternative strategy for pediatric renal revascularization. Here, we report on a 10-year-old, female, Javanese patient with bilateral TARAS who underwent DES implantation. Her clinical presentation was hypertensive crisis and worsened renal function. Bilateral renal artery DES implantation was performed successfully without complications. The child’s blood pressure was controlled using two anti-hypertensive medications after DES implantation and her renal function recovered. Dual anti-platelet therapy was given to minimize the risk of stent thrombosis.

Hypertension crisis as the first symptom of renovascular hypertension in children

BACKGROUND

Renovascular hypertension (RVH) is one of the main causes of hypertensive crisis (HTN-C). It is characterized by acute onset and severe disease, and early diagnosis and treatment are difficult. The objective was to describe the characteristics of RVH and factors associated with RVH leading to HTN-C in children. At present, there are few clinical studies on RVH in children with large cases in China.

METHODS

This study retrospectively analyzed the clinical data of inpatient children with RVH. Patients were divided into non-hypertensive crisis (non-HTN-C) group, and HTN-C group according to the first symptoms and blood pressure. Further, HTN-C were classified as hypertensive urgency (HTN-U) or hypertensive emergency (HTN-E).

RESULTS

Fifty-four pediatric cases (41 boys and 13 girls) were included. 83.3% of the RVH cases were ≥ 6 years old. Three cases were classified into the non-HTN-C group. Of the 51 HTN-C cases, 18 cases were grouped as HTN-U and 33 as HTN-E. The HTN-U group were mainly asymptomatic (50.0%, 9/18) while the HTN-E group mainly presented with neurological symptoms (72.7%, 24/33). The number of unknown etiology children was 32 (59.2%). The top three known etiologies were Takayasu's arteritis (50.0%, 11/22), congenital renal dysplasia (27.3%, 6/22) and fibromuscular dysplasia (13.6%, 3/22). As for the target organ damage of RVH, patients had a higher prevalence of left ventricular hypertrophy (71.4%, 35/49) and retinopathy (77.8%, 21/27).

CONCLUSIONS

Most RVH patients with HTN-C as the first symptoms, especially for males over 6 years old, should be assessed for RVH even if they were asymptomatic. Most asymptomatic patients with RVH already had target organ damage, and symptomatic patients even developed life-threatening complications. As preventive measures, routine monitoring of BP during children's physical examinations is advised.

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.

Successful Surgical and Endovascular Multidisciplinary Therapy for Mid-aortic Syndrome with Complicated Atherosclerotic Comorbidities in an Older Patient

Mid-aortic syndrome (MAS) is a rare vascular disorder that causes refractory hypertension. A 76-year-old woman was hospitalized for acute heart failure (HF) with drug-resistant hypertension; other comorbidities included epigastric artery rupture, old myocardial infarction, an intraventricular thrombus, and a cerebral artery aneurysm. Angiography revealed severe narrowing of the descending aorta, which led to the diagnosis of MAS. Although intensive medical treatment improved her HF, optimal blood pressure (BP) could not be achieved. Percutaneous coronary intervention and surgical bypass for diseased aorta was then performed in two stages, resulting in the achievement of optimal BP and alleviation of HF.

Presentation, treatment, and outcome of renovascular hypertension below 2 years of age

Renovascular hypertension in most cases requires endovascular treatment and/or surgery. This is technically much more difficult in small children and there is very limited published knowledge in this age group. We here present treatment and outcome of young children with renovascular hypertension at our institution. Children below 2 years of age, with renovascular hypertension between January 1998 and March 2020 were retrospectively reviewed. Demographics and treatment modalities were noted. Primary outcome was blood pressure within a week after the procedures and at last available visit. Sixty-six angiographies were performed in 34 patients. Median age at time of first angiography was 1.03 (interquartile range (IQR) 0.4-1.4) years and systolic blood pressure at presentation 130 (IQR 130-150) mm Hg. Thirty-eight percent (13/34) of children were incidentally diagnosed and 18% (6/34) presented with heart failure. Twenty-six (76%) children had main renal artery stenosis and 17 (50%) mid-aortic syndrome. Seventeen (50%) children showed intrarenal, six (18%) mesenteric, and three (9%) cerebrovascular involvement. Twenty patients underwent 45 percutaneous transluminal angioplasty procedures and seven children surgeries. In 44% of the 16 patients who underwent only percutaneous transluminal angioplasty blood pressure was normalized, 38% had improvement on same or decreased treatment and 19% showed no improvement. Complications were seen in 7.5% (5/66) of angiographies. In four of the seven (57%) children who underwent surgery blood pressure was normalized, two had improved (29%) and one unchanged (14%) blood pressure.

CONCLUSION

In small children with renovascular hypertension below the age of 2 years, percutaneous transluminal angioplasty caused significant improvement in blood pressure with low complication profile. Surgery can be recommended where percutaneous transluminal angioplasty and medical treatments failed.

WHAT IS KNOWN

• Renovascular hypertension is diagnosed in all age groups from a few weeks of life until adulthood. • Both angioplasty and surgery are significantly more difficult to perform in small children and the published information on short and long-term outcome in these children is very scarce.

WHAT IS NEW

• Children below the age of two years can safely and successfully undergo selective renal angiography and also safely be treated with angioplasty. • We here present a large group of babies and infants where angioplasty and in some cases surgery effectively and safely improved their blood pressure.

The clinical and radiological cerebrovascular abnormalities associated with renovascular hypertension in children: a systematic review

Renovascular disease is an important secondary cause of hypertension in childhood. In this cohort, many may have undiagnosed cerebrovascular disease, and some children present acutely with cerebrovascular complications. However, these associations are yet to be defined in the literature.A systematic review of clinical and radiological abnormalities associated with renovascular hypertension in the global pediatric (< 18 years) population. The MEDLINE, Embase, and Google Scholar databases were searched, from database inception to 26 January 2021. Primary articles were unrestricted by study design and geographical location but were limited to those published in English.A total of 303 individuals (median age: 7.6 years [range 10 days-17.9 years]; M:F, 174:129) from 34 studies were included, across 13 countries. Twenty-seven individual cases were published for children with coexisting renovascular hypertension and cerebrovascular disease. Most children had bilateral renal artery stenosis, secondary to fibromuscular dysplasia and had coexisting occlusive cerebrovascular disease. The majority presented with neurological symptoms, and cerebral complication ranged from asymptomatic cerebrovascular stenosis to acute stroke and posterior reversible encephalopathy syndrome. The location or underlying etiology of the renovascular disease did not predict the location or extent of the cerebrovascular disease. The evidence from the cohort studies was limited, as none specifically established a cohort of children with coexisting disease. Furthermore, the conclusions drawn were subjected to considerable bias from the treating clinicians.A prospective cohort of children with renovascular hypertension and cerebrovascular complications should be established so the long-term prognosis and impact of treatment may be better understood.

Mid-term outcome of angioplasty for pediatric renovascular hypertension

PURPOSE

To evaluate the mid-term outcome of percutaneous transluminal renal angioplasty (PTRA) for pediatric renovascular hypertension (RVH).

MATERIALS AND METHODS

The clinical data of patients who underwent PTRA for RVH in our hospital from 2012 to 2019 were analyzed retrospectively. Post-procedural blood pressure, glomerular filtration rate (GFR) of the affected kidney, restenosis and complications were closely followed up.

RESULTS

The procedure of PTRA was performed in total of 30 children (20 males and 10 females), with a mean age of 7.32±0.74 years (40 days ∼13.92 years) and a mean weight of 24.99±2.26 kg (3.4 ∼ 53kg). The median follow-up period was 26.5 months (1 month ∼7.5 years). Technical success was achieved in 26 of 30 patients (86.7%). Three patients (10.0%) developed restenosis. Only 1 patient underwent stent implantation, and the stent fractured 8 months later, requiring further intervention. No other complication was found. In terms of clinical benefit of blood pressure control after the initial PTRA procedure, 15 patients (50%) were cured and 7 (23.3%) improved. There was no significant difference in etiology, lesion location and length between patients with clinical benefit and failure (p=0.06, 0.202 and 0.06). The GFR of the affected kidney was significantly improved from 19.85±11.24 (ml/min) to 38.09±11.88 (ml/min) at 6 months follow-up after PTRA (p<0.001).

CONCLUSION

The overall results of PTRA for pediatric RVH caused by different etiologies are promising. Not only does it provide clinical benefit of blood pressure control in 73.3% of patients, it also significantly improves the function of the affected kidney.

Validation of computed tomography angiography as a complementary test in the assessment of renal artery stenosis: a comparison with digital subtraction angiography

BACKGROUND

Renal artery stenosis is an important cause of hypertension in children, accounting for 5-10% of cases. When suspected, noninvasive imaging options include ultrasound (US), computed tomography (CT) angiography and magnetic resonance (MR) angiography. However, digital subtraction angiography (DSA) remains the gold standard.

OBJECTIVE

To investigate the accuracy and inter-reader reliability of CT angiography in children with suspected renal artery stenosis.

MATERIALS AND METHODS

This is a retrospective study of patients suspected of having renal artery stenosis evaluated by both CT angiography and DSA between 2008 and 2019 at a tertiary pediatric hospital. Only children who underwent CT angiography within 6 months before DSA were included. CT angiography studies were individually reviewed by two pediatric radiologists, blinded to clinical data, other studies and each other's evaluation, to determine the presence of stenosis at the main renal artery and 2nd- and 3rd-order branches. The sensitivity, specificity and accuracy were calculated using DSA as the reference. The effective radiation dose for CT angiography and DSA was also calculated. Kappa statistics were used to assess inter-reader agreement.

RESULTS

Seventy-four renal units were evaluated (18 girls, 19 boys). The patients' median age was 8 years (range: 1-21 years). Overall, CT angiography was effective in detecting renal artery stenosis with a sensitivity of 85.7%, specificity of 91.5% and accuracy of 88.9%. There was moderate inter-reader agreement at the main renal artery level (k=0.73) and almost perfect inter-reader agreement at the 2nd/3rd order (k=0.98). However, the sensitivity at the 2nd- and 3rd-order level was lower (14.3%). CT angiography provided excellent negative predictive value for evaluating renal artery stenosis at the main renal artery level (90.1%) and at the 2nd- or 3rd-order branches (82.7%). The median effective dose of CT angiography studies was 2.2 mSv (range: 0.6-6.3) while the effective dose of DSA was 13.7 mSv.

CONCLUSION

CT angiography has high sensitivity and specificity at the main renal artery level with a lower radiation dose than previously assumed. Therefore, it can be used as a diagnostic tool in patients with low to medium risk of renal artery stenosis, and as a screening and treatment planning tool in patients at high risk.

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.

Timing of procedural interventions in childhood renovascular hypertension

BACKGROUND

Renovascular hypertension (RVHTN) is a rare, often complex condition due to multiple etiologies including congenital stenoses, vasculitides, and fibromuscular dysplasia. Among children with RVHTN who require multiple and escalating medications to control blood pressure, the optimal timing of a procedural intervention involves a balance of numerous factors.

CASE-DIAGNOSIS/TREATMENT

In this presentation of a 1-month-old girl with RVHTN, the treating medical team had to consider multiple factors in the initial management and timing of interventions to treat her underlying cause of RVHTN, including concerns for kidney health, degree of hypertension, age and size of the patient, and potential methods of procedural intervention. Initially, she was treated conservatively until concern for poor renal growth arose and a durable surgical intervention was thought feasible and safe.

CONCLUSION

The evidence regarding the timing of non-medical interventions in pediatric RVHTN is limited. Considerations should include patient age, size, disease severity, comorbid conditions, and degree of medical management required to maintain safe blood pressures that allow for growth and reverse cardiac damage. The optimal interventions have not been evaluated by controlled trials and should be decided on a case-by-case basis with consideration of center expertise and family preferences.

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.

Complex Vascular Revascularization in a Young Woman with Type 1 Neurofibromatosis

We present an uncommon case of a 16-year-old woman with type 1 neurofibromatosis and renovascular hypertension due to bilateral renal stenosis associated with asymptomatic digestive artery stenosis. Our patient was treated by several autologous bypasses to the superior mesenteric artery and the left and right renal arteries. She had no postoperative complications and good clinical and imaging outcomes at 10 years. Furthermore, there are few data on the vascular impairment of this rare disease, thus justifying its presentation.

Surgical management of pediatric renin-mediated hypertension secondary to renal artery occlusive disease and abdominal aortic coarctation

BACKGROUND

Renovascular hypertension (RVH) associated with renal artery and abdominal aortic narrowings is the third most common cause of pediatric hypertension. Untreated children may experience major cardiopulmonary complications, stroke, renal failure, and death. The impetus of this study was to describe the increasingly complex surgical practice for such patients with an emphasis on anatomic phenotype and contemporary outcomes after surgical management as a means of identifying those factors responsible for persistent or recurrent hypertension necessitating reoperation.

METHODS

A retrospective analysis was performed of consecutive pediatric patients with RVH undergoing open surgical procedures at the University of Michigan from 1991 to 2017. Anatomic phenotype and patient risk factors were analyzed to predict outcomes of blood pressure control and the need for secondary operations using ordered and binomial logistic multinomial regression models, respectively.

RESULTS

There were 169 children (76 girls, 93 boys) who underwent primary index operations at a median age of 8.3 years; 31 children (18%) had neurofibromatosis type 1, 76 (45%) had abdominal aortic coarctations, and 28 (17%) had a single functioning kidney. Before treatment at the University of Michigan, 51 children experienced failed previous open operations (15) or endovascular interventions (36) for RVH at other institutions. Primary surgical interventions (342) included main renal artery (136) and segmental renal artery (10) aortic reimplantation, renal artery bypass (55), segmental renal artery embolization (10), renal artery patch angioplasty (8), resection with reanastomosis (4), and partial or total nephrectomy (25). Non-renal artery procedures included patch aortoplasty (32), aortoaortic bypass (32), and splanchnic arterial revascularization (30). Nine patients required reoperation in the early postoperative period. During a mean follow-up of 49 months, secondary interventions were required in 35 children (21%), including both open surgical (37) and endovascular (14) interventions. Remedial intervention to preserve primary renal artery patency or a nephrectomy if such was impossible was required in 22 children (13%). The remaining secondary procedures were performed to treat previously untreated disease that became clinically evident during follow-up. Age at operation and abdominal aortic coarctation were independent predictors for reoperation. The overall experience revealed hypertension to be cured in 74 children (44%), improved in 78 (46%), and unchanged in 17 (10%). Children undergoing remedial operations were less likely (33%) to be cured of hypertension. There was no perioperative death or renal insufficiency requiring dialysis after either primary or secondary interventions.

CONCLUSIONS

Contemporary surgical treatment of pediatric RVH provides a sustainable overall benefit to 90% of children. Interventions in the very young (<3 years) and concurrent abdominal aortic coarctation increase the likelihood of reoperation. Patients undergoing remedial surgery after earlier operative failures are less likely to be cured of hypertension. Judicious postoperative surveillance is imperative in children surgically treated for RVH.

Efficacy of Antihypertensive Therapy in a Child with Unilateral Focal Fibromuscular Dysplasia of the Renal Artery: A Case Study and Review of Literature

Background: Fibromuscular dysplasia (FMD) is one of the important etiologies of renovascular hypertension in children. It is usually resistant to multiple antihypertensive agents and can cause extreme elevation in blood pressures, which can lead to end organ damage if not promptly diagnosed and treated. Treatment options include medical management with antihypertensive agents, balloon or stent angioplasties, surgical revascularization, and nephrectomy. The aim of the study was to review the efficacy of antihypertensive therapy only in the management of FMD in a very young child. Methods: This is a retrospective chart study with review of literature. Results: Here, we report a 22-month-old toddler who presented with severe resistant hypertension and cardiomyopathy who was found to have focal FMD of the right renal artery. She also presented with proteinuria, hyponatremia that was probably secondary to pressure natriuresis, hypokalemia, hyperaldosteronism, and elevated plasma renin activity. The stabilization of blood pressures was done medically with the usage of antihypertensive medications only, without the need for angioplasty or surgical revascularization. Conclusions: We demonstrate that surgical intervention may not always be necessary in the treatment of all cases of FMD, especially in a small child where such intervention may be technically challenging and lead to potential complications. Hence, medical management alone may be sufficient, at least for the short-term, in small children with controlled hypertension and normal renal function, with surgical intervention reserved for FMD with medication-refractory hypertension and/or compromised renal function.

European consensus-based recommendations for the diagnosis and treatment of rare paediatric vasculitides - the SHARE initiative

OBJECTIVES

The European initiative Single Hub and Access point for paediatric Rheumatology in Europe (SHARE) aimed to optimize care for children with rheumatic diseases. Systemic vasculitides are very rare in children. Consequently, despite recent advances, paediatric-specific information is sparse. The lack of evidence-based recommendations is an important, unmet need. This study aimed to provide recommendations for diagnosing and treating children with rare forms of childhood systemic vasculitis.

METHODS

Recommendations were developed by a consensus process in accordance with the European League Against Rheumatism standard operating procedures. A systematic literature review informed the recommendations, which were devised and evaluated by a panel of experts via an online survey, and two consensus meetings using nominal group technique. Recommendations were accepted when ⩾ 80% of experts agreed.

RESULTS

Ninety-three relevant articles were found, and 78 recommendations were accepted in the two consensus meetings. General, cross-cutting recommendations and disease-specific statements regarding the diagnosis and treatment of childhood-onset PAN, granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis, and Takayasu arteritis are provided.

CONCLUSION

These Single Hub and Access point for paediatric Rheumatology in Europe recommendations were formulated through an evidence-based consensus process to support uniform, high-quality standard of care for children with rare forms of paediatric systemic vasculitis.

Endovascular Management of Neurofibromatosis Type I-Associated Vasculopathy: A Case Series and Brief Review of the Literature

Purpose:

Neurofibromatosis type 1 (NF1) is an autosomal-dominant disorder found in approximately 1 of every 3000 individuals. Neurofibromatosis type 1 can have vascular manifestations including aneurysms, stenoses, and arteriovenous malformations. The purpose of this article is to describe the clinical manifestations of NF1 vasculopathy, discuss therapeutic options, and highlight endovascular therapies from our institutional experience.

Materials and Methods:

The radiology information system was searched for cases of NF1. Cases with vasculopathy managed with endovascular therapies were included. Demographics, clinical histories, procedural details, and outcomes were recorded. A review of the literature for the management strategies of NF1 vasculopathy was performed.

Results:

Two pediatric patients with NF1 were identified, both of whom presented with hypertension found to be secondary to renal artery stenosis. One of the patients also had infrarenal aortic narrowing. Both patients were successfully treated with balloon angioplasty, resulting in improved blood pressures. The review of the literature identified case series of pharmacologic, surgical, and endovascular therapies, although, endovascular therapies appear to be preferred due to lower morbidity and mortality.

Conclusions:

NF1 vasculopathy is a rare condition that most often presents with hypertension due to renal artery stenosis. In these situations, endovascular management is the preferred approach.

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.

Arterial Recanalization for Access for Arterial Intervention in Children: Techniques and Outcomes

PURPOSE

To assess technical success of arterial recanalization in children requiring repeated arterial access and intervention.

MATERIALS AND METHODS

Over 14 years, 41 attempts to cross 30 arterial occlusions were made in 22 patients (13 male, 9 female). Median patient age was 12 months (15 days-14 years), and weight was 7.6 kg (3.0-77.3 kg). Techniques and outcomes were recorded.

RESULTS

Twenty-five of 41 (61%) attempts at crossing an arterial occlusion were successful. Nineteen of 30 (63%) first attempts to cross occlusions were successful, and 6 of 11 (55%) repeat attempts were successful. The occluded segments were combinations of common femoral artery (n = 4), external iliac artery (n = 36), common iliac artery (n = 11), and aorta (n = 1). Complications occurred in 5 of 41(12%) attempts: 3 minor complications (hematoma, extravasation, and transient leg ischemia) and 2 major complications (rupture and thrombosis).

CONCLUSIONS

Arterial access by recanalization of occluded segments is technically feasible in children, with a low complication rate.

The management of pediatric renovascular hypertension: a single center experience and review of the literature

INTRODUCTION

Renal artery occlusive disease is poorly characterized in children; treatments include medications, endovascular techniques, and surgery. We aimed to describe the course of renovascular hypertension (RVH), its treatments and outcomes.

METHODS

We performed literature review and retrospective review (1993-2014) of children with renovascular hypertension at our institution. Response to treatment was defined by National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents at most-recent follow-up.

RESULTS

We identified 39 patients with RVH. 54% (n=21) were male, with mean age of 6.93 ± 5.27 years. Most underwent endovascular treatment (n=17), with medication alone (n=12) and surgery (n=10) less commonly utilized. Endovascular treatment resulted in 18% cure, 65% improvement and 18% failure; surgery resulted in 30% cure, 50% improvement and 20% failure. Medication alone resulted in 0% cure, 75% improvement and 25% failure. 24% with endovascular treatment required secondary endovascular intervention; 18% required secondary surgery. 20% of patients who underwent initial surgery required reoperation for re-stenosis. Mean follow-up was 52.2 ± 58.4 months.

CONCLUSIONS

RVH treatment in children includes medications, surgical or endovascular approaches, with all resulting in combined 79% improvement in or cure rates. A multidisciplinary approach and individualized patient management are critical to optimize outcomes.

TYPE OF STUDY

Retrospective comparative study LEVEL OF EVIDENCE: Level III.

Pediatric renovascular hypertension: Treatment outcome according to underlying disease

BACKGROUND

Renovascular hypertension (RVH) accounts for 5-10% of pediatric hypertension, and can be associated with underlying disease involving other organs. The purpose of this study was to evaluate the clinical characteristics and assess the treatment outcomes of Korean pediatric patients with RVH.

METHODS

The medical records of 25 Korean pediatric patients with RVH were retrospectively reviewed.

RESULTS

Twenty-four patients had underlying disease, and the most common cause was moyamoya disease (MMD; n = 10; 40%). Of 10 patients with MMD, seven had RVH prior to MMD. All patients required antihypertensive medication as the initial treatment and 22 patients subsequently underwent percutaneous transluminal angioplasty (PTA). The majority of patients with MMD had ostial lesions on angiography. Eight patients had favorable outcomes after the first PTA. One patient received nephrectomy, and two patients received bypass surgery because of restenosis after PTA and technical failure of PTA, respectively. During follow up, blood pressure was well-controlled in nine patients, but only four patients were able to discontinue medication. Eight patients had target-organ damage of the brain, heart, and retina at the time of initial diagnosis, and five patients developed chronic kidney disease during follow up.

CONCLUSION

The most common cause of RVH in Korean children is MMD, and RVH caused by MMD with an ostial lesion is associated with poor PTA outcomes. Angioplasty alone does not appear to control blood pressure effectively in MMD patients, and combined treatment is necessary to prevent target organ damage.

Long-Term Outcomes of Pediatric Renovascular Hypertension

BACKGROUND/AIMS

Renovascular hypertension (RVHT) is an important cause of childhood hypertension. This study evaluated the clinical characteristics and outcomes of Korean children with RVHT.

METHODS

Children treated for RVHT between 2000 and 2015 at our center were retrospectively reviewed.

RESULTS

Forty-six children were followed for a median of 6.5 (0.66-27.23) years. Forty-five percutaneous transluminal angioplasties (PTAs) were performed in 32 children. At the last visit, clinical benefit was observed in 53.3% of children. Patients with comorbid cerebrovascular disease (CVD) showed less favorable long-term outcomes after PTA (clinical benefit in 41.7% vs. 61.1% in others) and higher restenosis rates (50% vs. 31.6% in others). Surgical procedures (bypass or nephrectomy) were performed in 8 patients. After surgery, blood pressure was normalized in 2 patients, improved in 3 patients, and unchanged in the remaining patients. Between PTA group (n=21) and medication group (n=14), percentage of atrophic kidneys became higher after follow-up period in medication group than in PTA group (60.0% vs. 26.1%, P=0.037).

CONCLUSION

Aggressive treatment of pediatric RVHT yielded fair outcomes in our cohort. CVD comorbidity was associated with relatively poor PTA outcomes. To confirm our findings, larger cohort studies with a longer follow-up period are warranted.

Sonographic diagnosis of mid-aortic syndrome in a 2-year-old patient with hypertension

Mid-aortic syndrome is a rare cause of hypertension in the paediatric population. We present here the sonographic findings of a 2 year old who presented with hypertension. Mid-aortic syndrome was diagnosed upon finding renal artery and infrarenal aortic stenoses on ultrasound. The clinical entity and interrogation of the paediatric renal and aortic vessels are discussed.

Nuclear Medicine in Pediatric Nephro-Urology: An Overview

In the context of ante-natally diagnosed hydronephrosis, the vast majority of children with a dilated renal pelvis do not need any surgical treatment, as the dilatation resolves spontaneously with time. Slow drainage demonstrated at Tc-99m-mercaptoacetyltriglycine (MAG3) renography does not necessarily mean obstruction. Obstruction is defined as resistance to urinary outflow with urinary stasis at the level of the pelvic-ureteric junction (PUJ) which, if left untreated, will damage the kidney. Unfortunately this definition is retrospective and not clinically helpful. Therefore, the identification of the kidney at risk of losing function in an asymptomatic patient is a major research goal. In the context of renovascular hypertension a DMSA scan can be useful before and after revascularisation procedures (angioplasty or surgery) to assess for gain in kidney function. Renal calculi are increasingly frequent in children. Whilst the vast majority of patients with renal stones do not need functional imaging, DMSA scans with SPECT and a low dose limited CT can be very helpful in the case of complex renal calculi. Congenital renal anomalies such as duplex kidneys, horseshoe kidneys, crossed-fused kidneys and multi-cystic dysplastic kidneys greatly benefit from functional imaging to identify regional parenchymal function, thus directing further management. Positron emission tomography (PET) is being actively tested in genito-urinary malignancies. Encouraging initial reports suggest that F-18-fluorodeoxyglucose (FDG) PET is more sensitive than CT in the assessment of lymph nodal metastases in patients with genito-urinary sarcomas; an increased sensitivity in comparison to isotope bone scans for skeletal metastatic disease has also been reported. Further evaluation is necessary, especially with the promising advent of PET/MRI scanners. Nuclear Medicine in paediatric nephro-urology has stood the test of time and is opening up to new exciting developments.

Outcomes of percutaneous transluminal angioplasty for pediatric renovascular hypertension

BACKGROUND

Up to 10% of hypertensive children will have renovascular disease. Where medical therapy fails to control the hypertension, endovascular techniques can improve renal perfusion. The purpose of this study was to assess the efficacy of angioplasty in controlling renovascular hypertension (RVH) in children.

METHODS

This is a single-center, retrospective review of patients who underwent angioplasty for RVH between 1992 and 2009. All patients were selected from the Interventional Radiology database. The primary outcome measure was clinical success as reflected by a favorable, sustained response in blood pressure for at least 1year following the angioplasty.

RESULTS

Two hundred sixteen patients underwent diagnostic angiography for suspected RVH, of these 28 required 42 angioplasties. Ten (36%) were cured, 9 (32%) were improved and 9 (32%) failed to respond to treatment. Major complications occurred in three patients and minor complications occurred in 18 angioplasties. Fibromuscular dysplasia (FMD) was the most common diagnosis in this series and was associated with a 79% success rate.

CONCLUSION

In our exclusively pediatric population angioplasty safely improved blood pressure control in 68% of patients, more than half of which are cured. FMD appeared to have the best clinical outcomes in our series.

Treatment of a recurrent renal artery stenosis and stent fracture using a drug eluting stent in a pediatric patient

Renal artery obstruction is uncommon in the pediatric population and therefore represents a challenging diagnosis to ascertain and treat. While angioplasty and surgery have been used to treat it, stent implantation has been left mainly for adult use. In the following paper, we expose the case of an 8-year-old female who presented with severe arterial hypertension. Initially, the patient was evaluated and up to 5 antihypertensive medications were started. After complete evaluation, she was found to have severe right renal artery distal and proximal stenosis. She underwent recurrent angioplasties and then a bare metal stent (BMS) implantation, due to recurrence of stenosis. The original BMS developed a circumferential fracture, leading to a second stent implant, this time using a drug eluting stent (DES). She has been stable for 8 years since the last intervention, although using 2 antihypertensive medications. The use of BMS and DES may add another tool in the armamentarium of the pediatric interventionist to treat these children with recurrent stenosis that fail angioplasty.

Remedial operations for failed endovascular therapy of 32 renal artery stenoses in 24 children

BACKGROUND

Percutaneous transluminal angioplasty (PTA) for the treatment of pediatric renovascular hypertension (RVH) in contemporary practice is accompanied with ill-defined complications. This study examines the mode of pediatric renal PTA failures and the results of their surgical management.

METHODS

Twenty-four children underwent remedial operations at the University of Michigan from 1996 to 2014 for failures of renal PTA. Their clinical courses were retrospectively reviewed and results analyzed.

RESULTS

Renal PTA of 32 arteries, including 13 with stenting, was performed for severe RVH in 12 boys and 12 girls, having a mean age of 9.3 years. Developmental ostial stenoses affected 22 children. PTA failures included: 27 restenoses and five thromboses. Remedial operations included: 13 renal artery-aortic reimplantations, one segmental renal artery-main renal artery reimplantation, ten aortorenal bypasses, one arterioplasty, one iliorenal bypass, and six nephrectomies for unreconstructable arteries; the latter all in children younger than 10 years. Follow-up averaged 2.1 years. Postoperatively, hypertension was cured, improved, or unchanged in 25, 54, and 21 %, respectively. There was no perioperative renal failure or mortality.

CONCLUSIONS

Renal PTA for the treatment of pediatric RVH due to ostial disease may be complicated by failures requiring complex remedial operations or nephrectomy, the latter usually affecting younger children.

Differences between the pediatric and adult presentation of fibromuscular dysplasia: results from the US Registry

BACKGROUND

Fibromuscular dysplasia (FMD) is a non-inflammatory arteriopathy that causes significant morbidity in children.

METHODS

The clinical features, presenting symptoms, and vascular beds involved are reviewed in the first 33 patients aged <18 years who are enrolled in the United States Registry for FMD from five registry sites and compared with 999 adult patients from 12 registry sites.

RESULTS

Mean age at diagnosis was 8.4 ± 4.8 years (16 days to 17 years). Compared with adults, pediatric FMD occurs in more males (42.4 vs 6 %, p < 0.001). Children with FMD have a stronger previous history of hypertension (93.9 vs 69.9 %, p = 0.002). Hypertension (100 %), headache (55 %), and abdominal bruits (10.7 %) were the most common presenting signs and symptoms. FMD affects renal vasculature in almost all children (97 vs 69.7 %, p = 0.003). The extra-cranial carotid vessels are less commonly involved in children (23.1 vs 73.3 %, p < 0.001). The mesenteric arteries (38.9 vs 16.2 %, p = 0.02) and aorta (26.3 vs 2.4 %, p < 0.001) are more commonly involved in children.

CONCLUSIONS

In the United States Registry for FMD, pediatric FMD affects children from infancy throughout childhood. All children presented with hypertension and many presented with headache and abdominal bruits. In children, FMD most commonly affects the renal vasculature, but also frequently involves the mesenteric arteries and abdominal aorta; the carotid vessels are less frequently involved.

Associated extrarenal vascular diseases may complicate the treatment and outcome of renovascular hypertension

AIM

This studied reviewed renovascular hypertension (RVH) due to renal artery stenosis (RAS) in two Serbian paediatric centres from 2001 to 2013.

METHODS

The patients' demographic data, underlying syndromes, blood pressure (BP), antihypertensive treatments and outcomes were reviewed.

RESULTS

The incidence of RVH was 1.9 per million children per year during the study period, and there were 25 patients with RAS, aged 10.4 ± 5.2 years. At presentation, their mean blood pressure (BP) standard deviation scores were 6.9 ± 3.4 systolic and 5.2 ± 2.6 diastolic. BP loads on 24-hour ambulatory BP were 88 ± 14% systolic and 80 ± 29% diastolic. We found that 72% had fibromuscular dysplasia and 28% had underlying syndromes. RAS was unilateral in 64% and bilateral in 28%, and 8% had RAS of a single kidney. Antihypertensive treatment included antihypertensive drugs (100%), percutaneous transluminal angioplasty (92%), renal auto-transplantation (16%), surgical revascularisation (12%) and nephrectomy (12%). After 4.4 ± 3.6 years of follow-up, high BP was cured in 40% of the patients and 39.4% of the kidneys and improved in 48% (75.7%), with BP decreases of 20.3 ± 3.7% systolic and 16.3 ± 6.2% diastolic.

CONCLUSION

Fibromuscular dysplasia was the most common cause of RVH in this study, and hypertension was cured or improved in 88% of the patients.

A reappraisal of pediatric abdominal surface anatomy utilizing in vivo cross-sectional imaging

Despite being integral to medical and surgical practice, pediatric anatomy has remained relatively neglected except for a few landmark works. Neonatal and pediatric anatomy differs structurally and functionally from adult anatomy in many ways. The aim of the current study was to reappraise common abdominal surface landmarks of important structures in infants and children. After cases with related pathologies had been excluded, computer tomography scans of 90 children were divided into three age groups and systematically analyzed. The vertebral levels of the unpaired branches of the abdominal aorta (AA) were recorded. The vertebral level and relationship to the midline of the bifurcation of the AA and the formation of the inferior vena cava were measured. The renal long axes, costal relationships, renal artery vertebral levels, and hilar vertebral levels were measured. The splenic long axis and relationship to the mid-axillary line were also measured. The renal length was disproportionately large in the youngest age group and increased less with age (7.12 cm, 7.85 cm, 8.86 cm). The renal artery was consistently found around L1; the left kidney was related to the 11th and 12th ribs posteriorly, the right kidney only to the 12th rib. The AA bifurcated to the right of the midline in 10% of children. The unpaired visceral branches of the aorta were commonly found at T12 (celiac artery), L1 (superior mesenteric artery), and L3 (inferior mesenteric artery). The current study provides age-standardized surface landmarks and measurements for major abdominal vascular structures and solid organs in normal children. The clinical applications of these data are multiple and diverse.

Renovascular hypertension: a case with atypical neurological signs

Secondary hypertension is the most frequent form of hypertension in children. Renovascular disease accounts for 5-10% of all childhood hypertension and should be suspected in the presence of severe hypertension found difficult to manage with medical therapy. Uncontrolled hypertension can lead to severe target organ damage. We describe the case of a 13-month-old baby boy with failure to thrive, recent muscular weakness of the lower extremities and irritability. Hypertension was detected and he was admitted to the paediatric intensive care unit with a refractory hypertensive emergency, despite multiple antihypertensive therapies. Bilateral renal artery stenosis was diagnosed through renal angiography and balloon dilation was performed, leading to lower blood pressure. He is currently withdrawing from antihypertensive medication, and slowly gaining weight and recovering from target organ damage. However, weakness of the lower extremities persists and he has been diagnosed with a neurogenic bladder.

Management of the renovascular disease in children with Takayasu arteritis

Takaysu arteritis (TA), together with fibromuscular dysplasia, is the most common cause for renovascular hypertension. The diagnosis of vasculitis is important to make as these children benefit from immunosuppressive treatment. In many cases, however, it is more difficult than commonly realised to differentiate between these two diagnoses. Imaging which allows the inflamed arterial wall to be outlined, such as magnetic resonance or positron emission tomography scans, can be very helpful in this context. Revascularisation, either with angioplasty or surgery, seems to be effective and safe, also in children with TA. Patients with inactive disease have a more successful outcome and experience fewer complications from the intervention than those with active on-going inflammation.

Impact of revascularization on hypertension in children with Takayasu's arteritis-induced renal artery stenosis: a 21-year review

BACKGROUND

Surgery for reno-vascular hypertension (RVH) is complex, and the techniques utilized vary with anatomical presentations of the disease. The long-term outcome of revascularization on RVH in children with Takayasu's arteritis (TA)-induced renal artery stenosis (RAS) at our centre was reviewed.

METHODS

This study was a 21-year retrospective review of pre- and post-intervention RVH in children with angiographically confirmed RAS. The outcome of hypertension was defined as follows: (1) cured (normotensive off anti-hypertensives), (2) improved (normotensive on same or reduced number of medications), or (3) failure (no cure or improvement in number of medications).

RESULTS

The medical histories of 59 children (median age 9.98 years) were reviewed, of whom 20 (44 %) had revascularization procedures. All were hypertensive, with a mean systolic and diastolic blood pressure of 161.5 ± 36 and 106.5 ± 31 mmHg, respectively. RAS was present in 45 (76.3 %) children. Twenty-four revascularization procedures were performed in 20 children (44 %), of whom five had contralateral nephrectomies. Outcome was available for 17 patients at the 3- and 6-months follow-up, with cure, improvement and failure rates at 3 months of 2/17 (11.8 %), 7/17 (41.2 %) and 8/19 (47 %), respectively, and similar rates at 6 months. Associations between outcome and age (p = 0.51), sex (p = 0.32), number of pre-surgery anti-hypertensives (p = 0.18) and stenosis sites (p = 0.22) were not statistically significant.

CONCLUSIONS

Revascularization was beneficial to the management of blood pressure control in about half of our RVH patients.

Angioplasty for pediatric renovascular hypertension: a 13-year experience

PURPOSE

We aimed to evaluate the long-term outcome and efficacy of percutaneous transluminal renal angioplasty (PTRA) for pediatric renal artery stenosis (RAS), which is an important cause of medication-refractory pediatric hypertension.

MATERIALS AND METHODS

We retrospectively evaluated 22 hypertensive children (age range, 3-17 years) who underwent PTRA from February 2000 to July 2012. Sixteen patients had Takayasu arteritis and six fibromuscular dysplasia. Five were not included in the statistical analysis due to loss to follow-up.

RESULTS

Technical success was achieved in 32 of 34 procedures (94.1%). The stenosis rate decreased from 84.5% before PTRA to 20.1% after PTRA. Treatment was effective in 72.7% (16/22) of patients, including complete cure in 27.3% (6/22) and improvement in 45.5% (10/22). Systolic and diastolic blood pressures decreased from 153 ± 19.1 to 131.7 ± 21.4 mmHg and from 97.9 ± 14.2 to 83.6 ± 19.3 mmHg, respectively (P <0.01). Number of antihypertensive agents decreased from 2.7 to 0.5 per patient. Restenosis was detected in 40.9% (9/22) of patients, with a restenotic interval of 11.8 months (range, 3-47 months). Lesion length was strongly correlated with clinical success (cure and improvement) (independent-sample t test, P <0.001; binary logistic regression, P = 0.040).

CONCLUSION

Lesion length is an important determination of clinical success with PTRA for pediatric RAS. PTRA is an appropriate treatment option for pediatric renovascular hypertension due to Takayasu arteritis and fibromuscular dysplasia.

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.

Angioplasty for recurrent renal artery stenosis in flare-up of Hashimoto's thyroiditis

Takayasu arteritis is the most common disease seen in children presenting with renovascular hypertension (RVH) in Asia, and can manifest anatomically as renal artery stenosis (RAS). We report the case of a 16-year-old girl presenting with RVH due to recurrent and novel RAS in Hashimoto's thyroiditis (HT) flare-up. After treatment with thyroxin and percutaneous transluminal renal angioplasty (PTRA), she was free of hypothyroidism and systemic hypertension. RVH due to recurrent and novel RAS in HT flare-up has not previously been reported in the English-language literature. PTRA is the procedure of choice, providing there is no renal artery dissection or aneurysm.

Clinical efficacy of percutaneous transluminal renal artery stenting for the treatment of renovascular hypertension associated with Takayasu arteritis

BACKGROUND

This study aims to observe and analyze the clinical efficacy of interventional therapy for patients with Takayasu arteritis (TA) experiencing renovascular hypertension (RH).

METHODS

Eight TA patients with RH underwent percutaneous transluminal renal artery stenting (PTRAS). Patients were followed up 1, 6, 12, and 24 months postoperatively for levels of blood pressure, number of antihypertensive drugs being taken, levels of serum creatinine, and the presence of renal artery restenosis.

RESULTS

All 8 patients were successfully followed up 1, 6, and 12 months postoperatively, but 1 was lost to follow-up at 24 months. All patients had significantly lower average blood pressure levels compared with those at baseline (P < 0.05); treatment efficacy rates (recovery or improvement) at 1, 6, 12, and 24 months were 94%, 90%, 80%, and 80%, respectively. The average number of antihypertensive drugs being taken was 3.5 at baseline, 1.0 at 1 month, 0.5 at 6 months, 1.0 at 12 months, and 1.5 at 24 months. Serum creatinine levels during the follow-up period were not significantly different from those at the baseline. No patient developed renal artery restenosis during the follow-up period.

CONCLUSIONS

PTRAS is a safe and effective treatment for TA-associated RH, with a high technical success rate and a low complication rate. This interventional therapy can effectively control TA-related hypertension and can also preserve and even improve kidney function.