Hepatomesenteric trunk: a rare variant with major surgical implications. A case report from a living donor for liver transplantation.

Anatomical variations of the hepatic artery are common, with the most frequent being the right hepatic artery arising from the superior mesenteric artery, described as Michels type III. A rarer variant, the hepatomesenteric trunk, occurs when both the common hepatic artery and superior mesenteric artery share a common origin from the abdominal aorta. This variation, classified as Michels type IX and Adachi type V, presents significant implications for hepatobiliary and pancreatic surgery, as well as liver transplantation. We report a case of a 27-year-old female living donor for liver transplantation, whose preoperative imaging revealed a hepatomesenteric trunk. This rare variant required careful surgical planning, especially in the context of liver donor hepatectomy. The recognition of such variations is crucial for preventing inadvertent vascular injury and ensuring optimal graft perfusion. The case highlights the importance of preoperative vascular imaging and tailored surgical strategies in managing complex vascular anatomies.