Abstract
Aneurysm and rupture of visceral artery are rare, but they are life-threatening and important diseases. An arc of Riolan connecting between superior mesenteric artery (SMA) and inferior mesenteric artery (IMA) is one of the collateral artery of splanchnic artery. Among the aneurysms of visceral artery, an aneurysm of IMA is few, and there has never been reported a case of ruptured of an arc of Riolan. We experienced a case of intraperitoneal bleeding due to a rupture of the arc of Riolan with a stenosis of SMA. When the 73-years-old female attended to our department, her vital signs were stable and active bleeding and intestinal infarction were not considered, so we chose medically treating for her. Collapsed arc of Riolan was to be thrombotic occluded and spontaneously disappeared, and she didn’t complain of symptoms of abdominal angina after starting oral ingestion. After her general condition became stable, we performed revascularization of the SMA via a common iliac to SMA vein bypass. We could successfully medically treat intraperitoneal bleeding due to collapse of small vessels, as the bleeding spontaneously stopped and an intestinal infarction didn’t occur for abundant collateral artery between splanchnic arteries.
