The surgical management of renovascular hypertension in children and young adults

A child with spontaneous resolution of idiopathic mid-aortic syndrome presented with dilated cardiomyopathy

Mid-aortic syndrome is an uncommon vascular disease characterised by lower thoracic and upper abdominal aorta stenosis and can occur even in neonatal or infant periods. Here, we report an interesting case of a 2-month-old female with diffuse hypoplasia of the lower abdominal aorta and secondary dilated cardiomyopathy. In our patient, her abdominal aortic narrowing spontaneously normalised over time with the administration of consistent and goal-directed heart failure therapy, supporting adequate growth and natural recovery.

The Use of Systematic Clinical Approach in Diagnosing Rare Cases of Secondary Hypertension: A Case Report of Mid Aortic Syndrome in a Young Patient

Mid aortic syndrome (MAS) is a rare disease that occurs in children and young adults. The most important clinical feature reflecting vascular involvement is the presence of systemic hypertension. The diagnosis is usually made during the imaging assessment of secondary hypertension when routine echocardiography fails to identify the characteristic morphological or Doppler flow patterns associated with thoracic arch coarctation in the presence of the clinical features of aortic vascular obstruction. In this report, we present a case of a 22-year-old male who presented with systemic hypertension not responding to medical treatment, and whose systematic diagnostic workup revealed the diagnosis of MAS involving both renal arteries.

Application of Duplex Ultrasonography in the Midaortic Syndrome

Objective

Midaortic syndrome is a rare condition found primarily in children that causes stenosis of the abdominal aorta and its proximal branches. Duplex interpretation criteria derived from adults do not necessarily apply to the pediatric population but are sometimes used empirically in specific cases. We report the case of a 5-year-old girl whose aorta and renal arteries were studied by duplex ultrasound, with anatomic and radiologic correlation.

Case Report

The patient was a 5-year-old girl with refractory hypertension on multiple antihypertensive medications. Her initial diagnosis of midaortic syndrome was made via duplex ultrasound. The findings were confirmed by angiography and showed smooth narrowing of the mid- to distal abdominal aorta with concomitant bilateral renal artery origin stenosis. Surgical repair of the aorta was performed with the use of a patch angioplasty technique with pulmonary artery homograft. The left renal artery was re-implanted onto the infrarenal aorta and an aorta to right renal artery bypass graft was placed using autogenous left internal iliac artery. Duplex ultrasound was then used to evaluate the success of the surgical repair.

Conclusion

Duplex ultrasound proved effective in the preoperative and postoperative care of this small child with midaortic syndrome and renal artery stenosis. The standard adult criteria for renal artery stenosis can be used selectively in children to assist in the diagnosis of unusual vascular conditions.

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.

Disease Beyond the Arch: A Systematic Review of Middle Aortic Syndrome in Childhood

BACKGROUND

Middle aortic syndrome (MAS) is a rare clinical entity in childhood, characterized by a severe narrowing of the distal thoracic and/or abdominal aorta, and associated with significant morbidity and mortality. MAS remains a relatively poorly defined disease. This paper systematically reviews the current knowledge on MAS with respect to etiology, clinical impact, and therapeutic options.

METHODS

A systematic search of 3 databases (Embase, MEDLINE, and Cochrane Central Register of Controlled Trials) yielded 1,252 abstracts that were screened based on eligibility criteria resulting in 184 full-text articles with 630 reported cases of childhood MAS. Data extracted included patient characteristics, clinical presentation, vascular phenotype, management, and outcomes.

RESULTS

Most cases of MAS are idiopathic (64%), 15% are associated with Mendelian disorders, and 17% are related to inflammatory diseases. Extra-aortic involvement including renal (70%), superior mesenteric (30%), and celiac (22%) arteries is common, especially among those with associated Mendelian disorders. Inferior mesenteric artery involvement is almost never reported. The majority of cases (72%) undergo endovascular or surgical management with residual hypertension reported in 34% of cases, requiring medication or reintervention. Clinical manifestations and extent of extra-aortic involvement are lacking.

CONCLUSIONS

MAS presents with significant involvement of visceral arteries with over two thirds of cases having renal artery stenosis, and one third with superior mesenteric artery stenosis. The extent of disease is worse among those with genetic and inflammatory conditions. Further studies are needed to better understand etiology, long-term effectiveness of treatment, and to determine the optimal management of this potentially devastating condition.

Renal artery stenosis precipitates hyponatremic hypertensive syndrome and posterior reversible leukoencephalopathy

BACKGROUND

Hyponatremic hypertensive syndrome (HHS) is an uncommon disorder usually encountered in the adult population with unilateral renal artery stenosis and is under-recognized in the pediatric population.

CASE DIAGNOSIS/TREATMENT

A 19-month-old male presented with new-onset status epilepticus associated with neurological sequelae, and hypertension to a high of 248/150 mmHg. Lab work revealed significant hyponatremia, elevated peripheral renin activity, and increase in aldosterone and ADH levels. A diagnosis of HHS was made. Initial analysis revealed a high-grade proximal renal artery stenosis by magnetic resonance imaging (MRI) and angiogram. Electroencephalogram and an MRI of the brain demonstrated characteristic abnormalities of the left temporal-parietal regions consistent with posterior reversible leukoencephalopathy syndrome (PRES). The patient responded to right renal artery balloon dilation and stent placement. Since intervention and close blood pressure control with Amlodipine, the patient has been free of seizures and is neurologically intact.

CONCLUSION

We report a case of malignant hypertension in a 19-month-old male secondary to renal artery stenosis with associated HHS and PRES. Prognosis of PRES in children with renal disease is excellent. Prompt intervention may offer near complete resolution of physiologic and symptomatic effects of HHS and PRES due to high-grade renal artery stenosis. This report was written with parental consent for de-identified case presentation and radiographs for the educational benefit of other medical professionals.

Duplex ultrasound findings before and after surgery in children and adolescents with renovascular hypertension

We report our experience with duplex ultrasound in young patients with renal artery stenosis (RAS) or middle aortic syndrome (MAS) before and after surgery (1995 and 2009). Of 36 patients (mean age: 13 ± 7 y), 21 had RAS and 15 had MAS. For patients with RAS, the Vmax in the affected artery was 350 ± 111 cm/s before surgery and 145 ± 55 cm/s after surgery. The resistance index was 0.46 ± 0.1 in the post-stenotic kidney and increased to 0.60 ± 0.08 after revascularization. Determination of the flow profile in the iliac artery revealed triphasic flow. In individuals with MAS, Vmax in the aorta was 323 ± 98 and the resistance index in both kidneys was low, even in the absence of RAS. The flow profile in the iliac arteries was monophasic before surgery and became triphasic after surgery. Duplex ultrasound is useful for the evaluation of children and young adults both pre- and post-surgery. Duplex ultrasound criteria for RAS in adults appear to be applicable in children and young adults also. The diagnostic evaluation of suspected renal vascular disease should include assessment of the aorta and the flow profile in the iliac arteries, as this could help differentiate between aortic and isolated renal artery stenosis.

Renal artery stenosis: is angiography still the gold standard in 2011?

Renovascular hypertension (RVH) is an unusual cause of hypertension in children that is important to diagnose as it is potentially curable with angioplasty or surgery. Digital subtraction angiography is the gold standard for diagnosing RVH; for other methods like ultrasound, isotope studies, magnetic resonance angiography and computed tomography angiography sensitivity is still too low to reliably exclude RVH. Clinical and laboratory criteria that suggest RVH will be proposed and recommendations when digital subtraction angiography should be performed will be made. A treatment algorithm that suggests when to use medical treatment, interventional radiology and surgery in children with RVH will be given.

Surgical treatment and long-term outcome of renovascular hypertension in children and adolescents

OBJECTIVES

This article describes the long-term outcome of surgical treatment in children with renovascular hypertension (RVH) over a 40-year period.

DESIGN

Retrospective study.

MATERIALS AND METHODS

Twenty-five consecutive patients, aged 5-21 years, underwent renal artery (RA) repair from 1967 to 1995. The disease consisted of fibromuscular dysplasia in 17 patients, Takayasu's arteritis in 7 and neurofibromatosis type 1 in one patient.

RESULTS

Twenty-nine RAs were repaired. Primary procedures included aortorenal bypass (ARB) with prosthesis in 10 RAs, autologous vein in five or internal iliac artery in four as conduits, direct reimplantation (DR) in four and nephrectomy in two RAs. Immediate graft failure occurred in three patients despite no peri-operative deaths. After a mean follow-up of 24.4 years, seven patients required secondary nephrectomy. Autologous ARB or DR showed better RA patency and fewer chances for secondary nephrectomy than prosthetic ARB. Hypertension was cured or improved in 21 patients. The overall cumulative survival rate at 20 years was 84%. All five deaths, observed a mean of 12.6 years after the initial operation, were attributed to cardiovascular events.

CONCLUSIONS

Surgical treatment, especially autologous ARB or DR, seems to provide durable results for paediatric RVH. Long-term observation and control of hypertension is mandatory.

Novel Technique for Treatment of a Renal Artery Occlusion in a Child With Neurofibromatosis: A Combined Endovascular and Laparoscopic Approach

Neurofibromatosis is associated with mid-aortic dysplasia, renal artery aneurysms and renal artery ostial stenosis, or occlusions in about 1% of cases. We describe a novel approach to recanalize an occluded renal artery in a 10-year-old girl with neurofibromatosis and difficulty in pharmacologically controlling her hypertension. Normally, when reconstruction is required, an open operative technique is used. We report on the combined use of laparoscopic exposure and percutaneous retrograde puncture of the occluded renal artery, which could be recanalized and stented. The pros and cons of this new approach are discussed.

Mid-aortic syndrome: A case report and review of the literature

Renovascular disease is an important cause of secondary hypertension in children. In contrary to the adult patients whose major cause of renal artery stenosis (RAS) is atherosclerosis, fibromuscular dysplasia is responsible for the renovascular hypertension in most children. Mid-aortic syndrome (MAS) is a rare abnormality referring to an isolated disease of the distal thoracic and abdominal aorta resulting in significant tubular narrowing with stenosis of the visceral and renal arteries. It is usually diagnosed in young adults, but may present in childhood as a challenging problem. Patients with MAS are often first detected due to refractory hypertension. Other later presentations include intermittent claudication, congestive heart failure, renal insufficiency and symptoms of hypertensive associated end-organ damage. We report a case of a 16-year-old patient with MAS who suffered from malignant arterial hypertension. A percutaneous transluminal renal angioplasty (PTRA) was first performed, however the stenosis proved resistant to dilatation and only resulted in a minimal angiographic improvement. Due to persistent hypertension, an aortorenal bypass using the saphenous vein was performed. We also reviewed the literature on PTRA and the surgical management of RAS in MAS patients, in which PTRA often carries poor results.

Ascending aorta–abdominal aorta bypass with the reconstruction of superior mesenteric and bilateral renal arteries for mid-aortic syndrome

We report the surgical repair of a case of mid-aortic syndrome (MAS) in a 17-year-old female patient. She was initially diagnosed with renovascular hypertension at the age of 12 years. Aortitis syndrome was suspected, and she has been treated with antihypertensive drugs since then. Angiography revealed severe stenosis of the abdominal aorta and left renal artery and occlusion of the right renal artery and superior mesenteric artery (SMA); this confirmed the diagnosis of MAS. Due to progressive, uncontrollable hypertension, we performed an ascending aorta-abdominal aorta bypass with revascularization of SMA and both renal arteries. Her blood pressure normalized following the operation.

Treatment of severe renal artery stenosis by percutaneous transluminal renal angioplasty and stent implantation: review of the pediatric experience: apropos of two cases

The clinical course of two children with mid-aortic syndrome and renal artery stenosis (RAS) who suffered from severe arterial hypertension is described. Hypertension was uncontrollable by antihypertensive medication and was managed by percutaneous transluminal renal angioplasty (PTRA) with stent implantation. The pediatric experience with PTRA is limited, and there are only few cases reported with additional stent implantation. Complications of these procedures are well known from experience with adult patients. However, since surgical revascularization may be technically difficult especially in small children, PTRA with or without stenting should be considered as a valuable treatment option in pediatric RAS.

Renovascular disease in children and adolescents

PURPOSE

This retrospective review describes the surgical management of renovascular disease in 25 consecutive children and adolescents with severe hypertension.

METHODS

Patients </=21 years of age (mean age, 11.6 +/- 5.4 years; 12 females, 13 males) underwent repair of 34 renal arteries (RAs), and their management forms the basis of this report. Early and late blood pressure responses were adjusted for gender, age, and height. RA repair was evaluated by angiography, renal duplex sonography (RDS) scanning, or both. Primary patency and survival were estimated by product-limit methods.

RESULTS

Thirty-four RAs among 32 kidneys were repaired. Bilateral renal RA disease to a solitary kidney was present in nine patients. RA lesions included dysplasia (44%), RA hypoplasia (20%), midaortic syndrome (12%), RA aneurysm (12%), dissection (8%), and arteritis (4%). All patients had severe hypertension (>95 th percentile systolic or diastolic pressure adjusted for gender, age, and height). RA repair comprised 25 bypasses (73%) consisting of 28% saphenous vein, 60% hypogastric artery, and 12% polytetrafluoroethylene; 2 patch angioplasties (6%), and 7 reimplantations (21%). Branch RA exposure was required in 28 kidneys (88%), and branch reconstruction was required in 61%. Warm in situ repair was used in 53%, in situ cold perfusion in 24%, and ex vivo cold perfusion in 23%. Of six bilateral RA repairs, one was staged and two patients are awaiting a staged repair. Combined aortic reconstruction was required in three patients. No unplanned nephrectomy was performed. There were no perioperative deaths. Hypertension was cured in 36%, improved in 56%, and failed in 8% at mean follow-up of 46.4 +/- 7.8 months. The mean calculated glomerular filtration rate increased from 82.0 mL/min/1.73 m 2 preoperatively to 98.2 mL/min/1.73 m 2 postoperatively. The postoperative patency of 30 RA reconstructions was evaluated by angiography, RDS scanning, or both. At mean follow-up of 32.8 months (median, 21.2 months), primary RA patency was 91%. No failures were observed after 2 months follow-up. Estimated survival was 100% at 60 months, with one death 9 years after surgery.

CONCLUSIONS

Renovascular hypertension in children and adolescents was caused by a heterogeneous group of lesions. All patients had RA repair, with arterial autografts in most of the RA bypasses. Cold perfusion preservation was used in half of the complex branch RA repairs. These strategies provided 91% primary patency at mean follow-up of 32.8 months, with beneficial blood pressure response in 92%. Surgical repair of clinically significant renovascular disease in children and adolescents is supported by these results.

The role of unilateral nephrectomy in the treatment of nephrogenic hypertension in children

OBJECTIVES

To define the efficacy of unilateral nephrectomy in a large series of patients presenting with renal disease and hypertension, as the latter may be a prominent finding in children with nephrourological disease (renal parenchymal disease, renovascular disease, obstruction, renal dysplasia and cancer).

PATIENTS AND METHODS

We retrospectively reviewed the hospital and outpatient records of 118 children who presented for evaluation with hypertension, and who had a nephrectomy between 1968 and 2003. Patients included in the study were those who had a unilateral nephrectomy for benign renal hypertension with a normal contralateral kidney; in all, 21 had complete records and follow-up were evaluated. The hypertension was associated with primary renal disease, obstruction and renovascular disease. Blood pressure and medication requirements were compared before and after surgery, the blood pressure values also being compared with published nomograms.

RESULTS

Patients were diagnosed with hypertension at a median age of 5 years and had a nephrectomy at a median of 11 months after the diagnosis. The median follow-up after surgery was 39 months. Most patients responded well and became normotensive, or there was a reduction in the need for medication. The median time to normalization was 2, 10 and 11 days in patients with primary renal disease, obstruction and renovascular disease, respectively.

CONCLUSION

Nephrectomy is successful in normalizing blood pressure in children with benign renal hypertension and with a normal contralateral kidney.

Hyponatremic hypertensive syndrome (HHS) in an 18-month old-child presenting as malignant hypertension: a case report

Background

The combination of hyponatremia and renovascular hypertension is called hyponatremic hypertensive syndrome (HHS). Malignant hypertension as a presentation has been reported in adults with HHS but is rare in children.

Case presentation

An eighteen month-old male presented with drowsiness, sudden onset status epilepticus and blood pressure of 210/160. The electrolytes on admission revealed sodium of 120 mEq/L and potassium of 2.1 mEq/L. The peripheral renin activity (PRA) was 172 ng/ml/min (normal 3–11 ng/ml/min) and serum aldosterone level was 91 ng/dl (normal 4 to 16 ng/dl). Patient underwent angioplasty with no success, followed by surgical correction. Two years since the diagnosis, the blood pressure is controlled with labetolol and amlodipine (at less than sixth of the pre-operative dosages). The PRA is 2.4 ng/ml/min and aldosterone 15.5 ng/dl. The child not only had three renal arteries on left but all of them were stenosed which to best of our knowledge has not been described.

Conclusion

As uncommon as HHS with malignant hypertension may be in adults it is under-reported in children and purpose of the case report is to raise its awareness.