Introduction and importance: Superior mesenteric artery (SMA) syndrome, or aorto-mesenteric clamp syndrome, is a rare condition where the third portion of the duodenum is compressed between the aorta and the superior mesenteric artery. This syndrome often affects adolescents and young adults, with predisposing factors including significant weight loss, anatomical variations, and spinal deformities. Early diagnosis and intervention are critical for managing symptoms and preventing complications. Case presentation: A 14-year-old girl with a history of mitral insufficiency presented with persistent postprandial vomiting over four years. Despite minimal weight loss and stable vital signs, imaging studies revealed significant gastric and duodenal dilation, with a reduced aorto-mesenteric angle and distance, confirming SMA syndrome. Due to the chronicity of her symptoms, surgical intervention in the form of a gastrojejunostomy was performed, bypassing the compressed duodenal segment. Discussion: SMA syndrome is characterized by a reduced aorto-mesenteric angle and narrowing of the aortomesenteric distance, which can lead to duodenal compression. Risk factors include rapid weight loss and certain anatomical variations. Diagnosis relies on imaging, particularly CT angiography and gastroduodenal transit studies. While conservative management is the initial approach, up to 75 % of patients require surgical intervention. Various surgical techniques, including gastrojejunostomy, have been successful in providing symptomatic relief and improving quality of life. Conclusion: SMA syndrome should be considered in patients with chronic postprandial vomiting, particularly when conservative measures fail. Early diagnosis through imaging is essential, and surgical treatment, such as gastrojejunostomy, can offer significant symptom relief and improve patient outcomes in refractory cases.