Staged reconstruction for middle aortic syndrome

Midaortic syndrome and renovascular hypertension

Midaortic syndrome (MAS) is a rare condition characterized by stenosis of the abdominal aorta with or without the involvement of branch vessels. The majority of cases are thought to be idiopathic though MAS has been associated with a number of conditions including granulomatous vasculitis, neurofibromatosis-1 (NF-1), Alagille Syndrome, fibromuscular dysplasia (FMD), and Williams syndrome. Patients typically present with hypertension due to decreased renal perfusion. Less common presentations include renal insufficiency, heart failure, claudication, stroke, and abdominal pain. Imaging modalities help establish the diagnosis of MAS including duplex ultrasound, computed tomography angiography (CTA), magnetic resonance angiography (MRA), and angiography. Initial therapy focuses on medical management with antihypertensives prior to intervention. Invasive interventions are indicated when there is evidence of end organ damage or dysfunction such as decreased renal function, poorly growing kidneys, cerebrovascular accident, left ventricular hypertrophy or frank cardiac failure. Endovascular interventions may assist in diagnosis and may treat some lesions although reintervention rates are high. Most patients require some type of surgical intervention, and a variety of surgical options are available based on anatomic findings. Renal revascularization may be accomplished by renal artery bypass, autotransplantation, or renal artery reconstruction. Aortic lesions may be repaired using patch angioplasty or aortoaortic bypass. Mesenteric arteries do not typically require reconstruction as they are rarely symptomatic. More novel options include the use of tissue expanders to lengthen the aorta to allow for primary aortic reconstruction (TESLA) or the use of the meandering mesenteric artery as an autologous aortic bypass graft (MAGIC).

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.

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.

Midaortic syndrome: 30 years of experience with medical, endovascular and surgical management

BACKGROUND

Midaortic syndrome is often associated with refractory hypertension. The aim of our study was to better understand the short- and medium-term outcomes in this patient population utilizing a multidisciplinary management approach.

METHODS

We conducted a review of patients with midaortic syndrome treated at our institution over the past 30 years.

RESULTS

Fifty-three patients presented at a median age of 6.7 years (birth to 28.7 years). Thirty-five patients (66 %) underwent invasive management (percutaneous techniques: 21; surgical techniques: 5; both: 9). Percutaneous interventions were acutely successful in decreasing the gradient across the obstruction and degree of luminal stenosis. However, freedom from reintervention was 58 % at 1 year and 33 % at 5 years. Freedom from reintervention after a surgical procedure was longer: 83 % at 1 year and 72 % at 10 years. At the most recent follow-up, the majority of patients (69 %) were normotensive. The median duration between time of presentation and achievement of blood pressure control was 5.7 (0.4-21.1) years. The median number of anti-hypertensive medications was 1 (0-5).

CONCLUSIONS

A multidisciplinary management strategy which couples comprehensive medical management with catheter-based and surgical interventions can lead to adequate blood pressure control and preservation of end-organ function in patients with midaortic syndrome.

Middle aortic syndrome caused by Takayasu arteritis

The middle aortic syndrome (MAS) is a rare condition characterized by diffuse narrowing of the descending thoracic aorta, abdominal aorta, or both. It can be congenital or acquired due to several conditions. We report an 8-year-old girl who developed middle aortic syndrome due to Takayasu arteritis.

[Abdominal aorta coarctation: the first three case reports in our literature]

INTRODUCTION

Congenital coarctation of the thoracic aorta at the ligamentum arteriosum or the aortic arch is well recognized. But a much less common variety (0.5-2.0%) of aortic coarctation is located in the distal thoracic aorta or abdominal aorta or both and is often called "middle aortic syndrome" or "mid-aortic dysplastic syndrome". This represents serious pathological condition and indicates multidisciplinary therapy approach.

OUTLINE OF CASES

From 1996 to 2007, at the Vascular Surgery Clinic of the Institute for Cardiovascular Diseases "Dedinje", Belgrade, three patients were treated due to abdominal aorta coarctation, two females aged 55 and 50 and a 4-year-old child. The patients were treated surgically (by-pass with a prosthetic graft and patch angioplasty) and endovascular- percutaneous transluminal angioplasty (PTA) with and without a stent. The follow-up period was 3-70 months. In the 50-year-old patient, angiography showed severe narrowing of the suprarenal segment of the abdominal aorta. Thoraco-abdominal bypass with a 16 mm dacronic tubular graft was performed. In the 4-year-old patient angiography also showed a suprarenal aorta narrowing. In the first act patch angioplasty was performed and after PTA of the visceral arteries was done on several occasions. In the 55-year-old patient, after diagnostic angiography, infrarenal aorta coarctation was registered. PTA was performed with stent placement. All patients were asymptomatic on control check-ups.

CONCLUSION

Abdominal coarctation is a pathological disease which is seldom found in vascular surgery. Angiography is of major importance for setting the diagnosis and for the control of the results of surgical and nonsurgical treatment. The combination of surgical and endovascular treatment in our patients showed very good results in the studied period.

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.

[Middle aortic syndrome: a case report]

Middle aortic syndrome (MAS) results from a diffuse narrowing of the distal thoracic or abdominal aorta commonly involving both the visceral and renal arteries. Congenital, acquired, inflammatory, and infectious etiologies have been described. Symptoms typically occur within the first three decades of life and include hypertension, lower extremity claudication, and mesenteric ischemia. The condition is considered a life-threatening emergency as a result of the complications associated with severe hypertension. Diagnosis is made with magnetic resonance and computed tomography angiography. Surgical bypass grafting is the optimal method of treatment and must be tailored depending on the distribution of disease. We report one case of MAS treated with thoracic aorta to abdominal aorta bypass and reimplantation of the right renal artery.

Surgery of the abdominal aorta and its branches in children: Late follow-up

BACKGROUND

The aim of this study was to evaluate the late results in adult patients who underwent surgery of the abdominal aorta as children.

METHODS

During a 17-year period, eight children underwent surgery for lesions of the abdominal aorta. There were 6 boys and 2 girls, with an average age of 10 years. The presenting symptom that led to diagnosis of abdominal aortic lesions was hypertension in five cases and lower-limb claudication in three. The underlying disease was middle aortic syndrome in three cases, infrarenal aortic hypoplasia in two, infrarenal aortic aneurysm in two, and Takayasu's disease in one. Five children had associated renal artery lesions, including four with bilateral lesions and one with a unilateral lesion. Aortic bypass was used in all cases. A straight tube graft was placed between the distal descending thoracic or supraceliac aorta and the infrarenal aorta in six cases, and a bifurcated bypass was placed between the infrarenal aorta and the iliac arteries in two. Renal artery revascularization procedures (n = 9) included ex vivo repair with renal autotransplantation in five cases, direct reimplantation on the arch of Riolan in two, and direct reimplantation of the renal artery onto the aortic graft in two.

RESULTS

One patient died on postoperative day 1. The remaining seven patients recovered uneventfully. Mean follow-up was 10.2 years. No patient was lost to follow-up. Further surgical intervention was required in three patients. The indications for additional surgery were fibrosis of a renal artery reimplanted onto the graft at 3 years, deterioration of the aortoaortic graft at 5 years, and false iliac aneurysm at 20 years. All seven patients had normal physical development. The average increase in height and weight were 28.5 cm and 26.2 kg, respectively. All patients had normal sexual function, and two are parents. All patients are currently asymptomatic. Short Form 36 scores for quality-of-life parameters were 78% to 83%.

CONCLUSIONS

Late results of abdominal aortic surgery in children, in our experience, are encouraging. Quality of life in adulthood was excellent. Insofar as possible, correction should be deferred until the child is 8 to 10 years old so that a prosthesis of sufficient diameter can be used.

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.

Pediatric hypertension: recent literature

This article reviews selected recent literature specifically concerning pediatric hypertension, much of which has focused on measurement and monitoring of blood pressure, as well as on evaluating antihypertensive medications. Normative data for blood pressure in children have been widely available for some time, based upon seated in-office measurements. In recent years, ambulatory blood pressure monitoring (ABPM), facilitated by user-friendly instrumentation, has become more commonplace, though norms are not based on large populations. However, ABPM has important uses in assessing blood pressure as well as in monitoring antihypertensive. This review discusses issues involved in determining blood pressure, as well as the utility of ABPM in several situations. Recent developments concerning pediatric antihypertensive therapy are considered, as well as new information relevant to the diagnosis, course and treatment of hypertension in children and adolescents.