Spontaneous hemoperitoneum resulting from segmental arterial mediolysis

A case of transcatheter arterial embolization for intraperitoneal hemorrhage due to giant hepatic segmental arterial mediolysis

This study aimed to demonstrate the effect of transcatheter arterial embolization (TAE) on hepatic segmental arterial mediolysis (SAM). The patient, a 68-year-old female, suddenly developed right upper abdominal pain in October 2021, which was initially relieved. However, she was rushed to a local hospital the next day when her abdominal pain recurred. An abdominal computed tomography scan suggested a ruptured hepatic aneurysm; therefore, she was transferred to our hospital and admitted on the same day. On the first day after admission, she underwent emergency catheterization and N-butyl-2-cyanoacrylate (NBCA)/lipiodol embolization for an aneurysm in the hepatic S6. A multi-detector computed tomography on hospital day 8 to probe for extrahepatic lesions revealed multiple beaded irregularities in the superior mesenteric and bilateral renal arteries. A head magnetic resonance angiography performed on the ninth day showed no aneurysms or irregularities. She did well after TAE, did not have rebleeding, and was discharged on hospital day 16. Rupture of an aneurysm associated with SAM occurs frequently in the colonic and gastroepiploic arteries, and rupture of a hepatic aneurysm is relatively rare. TAE hemostasis was able to save the patient by preventing intraperitoneal bleeding caused by hepatic segmental arterial mediolysis.

Segmental arterial mediolysis (SAM): Systematic review and analysis of 143 cases

Segmental arterial mediolysis (SAM) is a rare but serious nonatherosclerotic, noninflammatory vasculopathy of unknown etiology that often results in dissection, aneurysm, occlusion, or stenosis of, primarily, the abdominal arteries. Current literature lacks consensus on diagnostic criteria and management options for SAM. This review summarizes 143 cases and aims to advance appropriate recognition and management of SAM. Literature review of all relevant SAM case studies from 2005 to 2018 yielded 126 individual SAM cases from 66 reports. We identified 17 additional SAM cases from our center, bringing our analysis to 143 patients. Patients with SAM were most commonly men (68%) in their 60s. Hypertension (43%), tobacco use (12%), and hyperlipidemia (12%) were common comorbidities. Abdominal pain (80%) and intraabdominal bleeding (50%) were the most common presenting symptoms. Computed tomography was the most frequently used imaging method (78%), and histology was available in 44% of cases. The most commonly affected vessels were the superior mesenteric (53%), hepatic (45%), celiac (36%), renal (26%), and splenic (25%) arteries with aneurysm (76%), dissection (61%), and arterial rupture (46%). Treatments included coil embolization (28%), abdominal organ surgery (24%), open arterial repair (21%), and medical management (20%). Case-specific treatment modalities yielded symptom relief in the vast majority (91%) of patients, with a mortality rate of 7%.

Segmental arterial mediolysis in splanchnic arteries: an uncommon cause of abdominal pain

Segmental arterial mediolysis is an uncommon arterial disease that primarily involves splanchnic arteries; abdominal pain is the most common clinical manifestation. We report the case of a 53-year-old male with postprandial diffuse abdominal pain of one month's standing. Physical examination was uneventful, and laboratory tests revealed no abnormal findings. Abdominopelvic CT/Angio-CT showed an increased caliber of the superior mesenteric artery resulting from eccentric circumferential wall thickening. The patent lumen had a segment with fusiform aneurysmal dilatation, 7 x 26 mm long. These vascular changes extended along a number of distal jejunal branches, which also presented complete lumen obliteration. Abdominal arteries were free from signs of arteriosclerotic disease. Findings were consistent with segmental arterial mediolysis.

Segmental Arterial Mediolysis with Preceding Symptoms Resembling Viral Infection Hampers the Differentiation from Polyarteritis Nodosa

A middle-aged man presented with a fever, arthralgia, gastrointestinal symptoms, headache, and rash. After two weeks, the patient suddenly complained of severe abdominal pain, and computed tomography revealed aneurysms in the hepatic and splenic arteries, which increased in size progressively. Given the elevated levels of inflammatory markers and orchitis, polyarteritis nodosa (PN) was initially suspected. Catheter embolization for the ruptured hepatic aneurysm and splenectomy for the large splenic ones were performed, and the pathological finding was consistent with segmental arterial mediolysis (SAM). Changes in inflammatory marker levels and aneurysmal size are also informative to differentiate SAM from PN.

Endovascular Repair of Ruptured Hepatic Artery Pseudoaneurysm Secondary to Fibromuscular Dysplasia

We describe successful endovascular treatment of a patient with fibromuscular dysplasia of the celiac axis leading to development of a common hepatic artery pseudoaneurysm with contained rupture. An 81-year-old woman was transferred to our quaternary care center with concern for a hepatic artery rupture. Further imaging demonstrated a common hepatic artery pseudoaneurysm with surrounding hematoma as well as multifocal areas of narrowing and dilatation in the celiac trunk consistent with fibromuscular dysplasia. A similar pattern was subsequently identified in the bilateral renal and carotid arteries. The patient underwent successful endovascular exclusion of the pseudoaneurysm with a balloon-expandable covered stent and was discharged home without incident. Fibromuscular dysplasia is a nonatherosclerotic arteriopathy that can lead to stenosis, occlusion, dissection, and aneurysm formation. While it primarily affects the carotid and renal arteries, there are rare case reports involving the mesenteric vasculature. Endovascular therapy appears to be a feasible treatment option for the complicated sequelae of this condition in the rare case of mesenteric arterial involvement.