Extra-Anatomic Bypass for the Treatment of Midaortic Syndrome in Children

Objective: This report aims to introduce the extra-anatomic bypass technique to treat the midaortic syndrome and to document its long-term effectiveness and durability.

Methods: Fourteen patients (mean age: 6.7 ± 3.76, median: 7 – 1, range: 8 months-11 years) were diagnosed to have midaortic syndrome, characterized by severe narrowing of the abdominal aorta with involvement of the renal and visceral branches. CT angiography showed variable length of high-grade midaortic stenosis. All children were hypertensive (mean blood pressure: 165 ± 15.7 mm Hg). Three have had previous nephrectomies. Six patients had a previous percutaneous transluminal renal artery angioplasty. All patients underwent extra-anatomic bypass by a left thoracoabdominal approach in 2 and a median sternotomy and transabdominal approach in 12. The aortic obstruction was relieved by descending aorta-abdominal bypass using Goretex prosthesis in 2 and a woven Dacron graft in 12, anastomosed distal to the narrowing of the abdominal aorta infrarenally, and proximally to the ascending aorta via a diaphragmatic tunnel.

Results: Perioperative course was unremarkable. There was a dramatic reduction in blood pressure in all and relief of intermittent claudication in six affected patients. One patient had renal artery reimplantation 2 weeks postoperatively because of recurrence of severe renal hypertension. At a mean follow-up of 5.8 years, there was neither reoperation nor mortality. Eleven had complete relief of hypertension, and two had mild hypertension. All patients have normal renal function. There were no signs/symptoms of visceral artery malperfusion. Growth and development proceeded normally. Follow-up MRT showed patent grafts without any strictures.

Conclusions: Extra-anatomic bypass provides an effective and long-term relief of hypertension and any malperfusion in midaortic syndrome.