Left-Sided Portal Hypertension Induced by Splenic Arteriovenous Malformation: A Case Report

BACKGROUND Left-sided portal hypertension (LSPH) is a rare condition that occurs when the splenic vein pressure elevated, which can lead to gastric varices, without abnormalities of hepatic function or esophageal varices. The main causes of LSPH are splenic vein compression, stenosis, and thrombosis. However, no cases of LSPH resulting from vascular malformation have been reported. In this case report, we describe our experience of a patient with LSPH caused by a splenic vein malformation. CASE REPORT The patient was a 53-year-old man who reported having melena for 2 weeks. Gastroscopy performed at another hospital revealed gastric varices, and abdominal contrast-enhanced computed tomography (CT) showed gastric fundal varices and splenic vascular malformation. The patient denied any history of pancreatitis, abdominal trauma, or related surgeries. After further examination, comprehensive imaging, including contrast-enhanced CT and magnetic resonance imaging (MRI), revealed tortuous vascular cluster between the splenic artery and vein, marked dilatation of the left gastric vein, and numerous collateral vascular branches surrounding the perigastric area, with no signs of cirrhosis and gastro-renal shunt or splenic-renal shunt. Therefore, we suspected he had LSPH caused by splenic arteriovenous malformation. To improve the melena, after analyzing the advantages and disadvantages of the surgical approach, we abandoned the embolization approach and opted for splenectomy and Hassab's operation. After Hassab's operation, LSPH caused by arteriovenous malformation was diagnosed by pathology and immunohistochemistry. CONCLUSIONS We report our experience with a rare case of LSPH caused by arteriovenous malformation. We suggest the importance of early differentiation of vascular malformations and non-invasive vascular testing in patients suspected of having LSPH.