Superior Mesenteric Artery Syndrome: a Prospective Study in a Single Institution

Superior mesenteric artery syndrome (SMAS) is a rare cause of duodenal obstruction, resulting from the compression of the duodenum between superior mesenteric artery and aorta. This prospective registry aims to describe demographic, clinical, and outcome features of patients suffering from SMAS and to point out the indications for surgery.

Between 2008 and 2016, patients with chronic gastrointestinal symptoms and diagnosis of SMAS were included. Demographics, clinical presentation, diagnosis, and surgical outcome were recorded. Symptoms were investigated with a standardized questionnaire. The diagnosis was achieved through barium swallow, CT/MR angiography (aortomesenteric angle ≤ 22°, distance ≤ 8 mm), endoscopy. All patients underwent duodenojejunostomy ± distal duodenum resection. At follow-up, symptom score and barium swallow were re-evaluated.

Thirty-nine patients (11 M/28 F, median age 38 years, median BMI 17.8 kg/m²) were included. Barium swallow showed a gastroduodenal dilation in 57% of patients, and a delayed gastroduodenal emptying in 38%. Median aortomesenteric angle was 11° and distance was 5 mm. All patients underwent duodenojejunostomy, and in 32 patients, a distal duodenum resection was also performed. At a median follow-up of 47 months, the overall symptom score significantly dropped (10 vs. 32, p < 0.0001) and BMI increased (19.5 vs. 17.8, p < 0.0001). Barium swallow at 2 months postoperatively showed an improvement in terms of gastroduodenal dilation and emptying in 38% of patients with preoperative pathological findings.

SMAS is a rare condition that should be suspected in cases of chronic, refractory upper digestive symptoms, particularly in females with low BMIs. Surgical treatment may improve symptoms and quality of life, although it is not curative in all cases. ClinicalTrials.gov Identifier: NCT03416647.