Segmental arterial mediolysis

Spontaneous Subdiaphragmatic Hemorrhage From an Aneurysm of Inferior Phrenic Artery

Inferior phrenic artery (IPA) aneurysms are the rarest type of visceral aneurysms. It usually occurs secondary to trauma, surgery, or as a complication of pancreatitis. In addition, it can be a manifestation of underlying systemic pathology such as vasculitis, collagen vascular disorders, sepsis, or segmental arterial mediolysis. It can be associated with hypertension in 43% of cases. The presentation of IPA aneurysm is nonspecific with abdominal pain, melena, hematochezia, and anemia. The ruptured and actively bleeding aneurysm can lead to hemorrhagic shock, and immediate management is required with angiography and endovascular embolization with coil or gel foam or stent etc. Inaccessible locations are reached with surgical intervention, but it is associated with high morbidity and mortality. We here report a rare case of spontaneously ruptured IPA pseudoaneurysm extending from the posterior mediastinum to the subdiaphragmatic area and managed with coil and gel foam embolization.

A review of histopathologic and radiologic features of non-atherosclerotic pathologies of the extracranial carotid arteries

Diseases of the carotid arteries can be classified into different categories based on their origin. Atherosclerotic carotid disease remains the most encountered arterial wall pathology. However, other less-common non-atherosclerotic diseases can have detrimental clinical consequences if not appropriately recognized. The underlying histological features of each disease process may result in imaging findings that possess features that are obvious of the disease. However, some carotid disease processes may have histological characteristics that manifest as non-specific radiologic findings. The purpose of this manuscript is to review various non-atherosclerotic causes of carotid artery disease as well as their histologic-radiologic characteristics to aid in the appropriate recognition of these less-commonly encountered pathologies.

A Case Report of Renal Infarcts Secondary to Segmental Arterial Mediolysis

Flank pain is an exceptionally common presenting symptom in the emergency and primary care setting; however, most clinicians may not include a differential diagnosis of renal infarct (RI) due to the reported low incidence of this condition. Delayed diagnosis or treatment intervention for RI can have dire consequences for the patient including hypertension and longstanding renal impairment. In this report, we review a case of a previously healthy 39-year-old male presenting with flank pain, which after extensive workup, was revealed to be caused by renal infarction from a renal artery dissection secondary to segmental arterial mediolysis (SAM).

A case of rectal cancer complicated with segmental arterial mediolysis (SAM) safely treated with curative resection - A case report

INTRODUCTION

Recent advances in diagnostic imaging techniques have led to an increasing number of case reports of segmental arterial mediolysis (SAM). However, reports of abnormalities associated with SAM of abdominal organs, including the bowel, are limited. SAM, a rare vascular disease that causes spontaneous intra-abdominal bleeding, including shock and intestinal ischemia, has been reported to be associated with high mortality, but it has not been reported to coexist with rectal cancer.

CASE PRESENTATION

A 74 year-old male was referred to our hospital with a rectal cancer and he was admitted for further examination. Computed tomography angiography (CTA) revealed dissection and aneurysm in the celiac artery, superior mesenteric artery (SMA), and the inferior mesenteric artery were dilated, leading to a diagnosis of SAM.

CLINICAL DISCUSSION

Surgery for rectal cancer requires cutting the inferior mesenteric artery. The risk of bleeding during surgery increases when SAM is associated with the inferior mesenteric artery. The radical surgery for rectal cancer was executed without complications, including significant bleeding. This was achieved through careful management of SAM, meticulous control of blood pressure throughout the surgical procedure, and the delicate treatment of the SMA. A pathological diagnosis of the resected inferior mesenteric artery at the time of radical surgery was performed, and a definitive diagnosis of SAM was made.

CONCLUSION

We present a first known case in which high anterior resection was successfully performed for rectal cancer complicated by SAM. The relationship between cancer and SAM is unclear and further case accumulation is needed.

Overview of Vasculitides in Adults

Vasculitis is characterized by the inflammation of blood vessels. Vasculitides refers to the different forms of vasculitis, often classified according to the size of the blood vessel that is involved. Vasculitis may occur as a primary process or secondary to many systemic diseases. This topic provides an overview of the clinical features, diagnosis, and classification of the different forms of vasculitides.

Gallbladder hemorrhage associated with segmental arterial mediolysis: a case report

BACKGROUND

Gallbladder hemorrhage is a rare but fatal condition. The reported causes of gallbladder hemorrhage include iatrogenesis, atherosclerotic changes in the cystic arteries, acute cholecystitis or cholelithiasis, malignancy, trauma, hemophilia, pseudoaneurysm, and the use of oral anticoagulant medications. Recently, segmental arterial mediolysis (SAM) has been reported as a possible etiology of life-threatening abdominal, retroperitoneal, and intracranial hemorrhages. However, no previous reports have described the association between gallbladder hemorrhage and SAM.

CASE PRESENTATION

A 59-year-old man was transferred to our hospital complaining of upper abdominal pain and vomiting. Contrast-enhanced computed tomography revealed high-density images of the gallbladder and common bile duct. However, there were no obvious findings of gallstones, cholecystitis, tumors, or aneurysms. He was diagnosed with gallbladder hemorrhage and bile duct obstruction. We performed a laparoscopic cholecystectomy after endoscopic biliary drainage. The gross appearance of the surgically resected specimen showed 12 small (3-12 mm), slightly elevated lesions on the gallbladder mucosa. Histologically, these slightly elevated lesions consisted of dilated muscular arteries of the gallbladder wall with fibrinoid degeneration of the media and focal loss of the internal and external elastic laminae. The histopathological diagnosis was confirmed as SAM.

CONCLUSIONS

To the best of our knowledge, this is the first reported case of a gallbladder hemorrhage associated with SAM. Our case report shows that SAM can cause gallbladder hemorrhage, suggesting that SAM should be considered in the differential diagnosis of gallbladder hemorrhage.

Differentiating between segmental arterial mediolysis and other arterial vasculopathies to establish an early diagnosis - a systematic literature review and proposal of new diagnostic criteria

Segmental arterial mediolysis (SAM) is a rare vascular disease, characterized by acute but transient vulnerability of the wall of medium-sized arteries. The most characteristic feature of SAM is its biphasic course: an injurious phase marked by acute weakness of the arterial wall leading to acute dissection and/or hemorrhage, followed by a reparative phase in which granulation tissue and fibrosis restore the injured arterial wall. Residual stenosis, aneurysms, and/or arterial wall irregularities may remain visible on future imaging studies. Differentiating between SAM and other arterial vasculopathies is difficult due to its similarities with many other vascular diseases, such as vasculitis, fibromuscular dysplasia, inherited connective tissue disorders, and isolated visceral artery dissection. In this systematic review, we provide an overview on SAM, with an emphasis on the differential diagnosis and diagnostic work-up. We propose new diagnostic criteria to help establish a prompt diagnosis of SAM, illustrated by case examples from our multidisciplinary vascular clinic.

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 with a ruptured visceral artery on two consecutive days

Background

We describe a case of segmental arterial mediolysis in which a vessel ruptured on two consecutive days.

Case Presentation

A 69-year-old man presented with sudden-onset abdominal pain. Computed tomography showed a hematoma in the gastric wall. The patient was discharged after the pain was relieved but returned 8 h later with abdominal pain and shock. Repeated computed tomography revealed a massive intra-abdominal hemorrhage without previous aneurysm formation. Emergency angiography and coil embolization were successfully carried out. Segmental arterial mediolysis was diagnosed after irregular vasodilated lesions were observed in multiple arteries.

Conclusion

This case suggests that accurately predicting the next vessel rupture is difficult. For patients experiencing intra-abdominal bleeding with segmental arterial mediolysis, we suggest treating only ruptured aneurysms and closely following-up unruptured aneurysms.

Intraperitoneal hemorrhage due to segmental arterial mediolysis associated with cerebral vasospasm after subarachnoid hemorrhage

A man in his 50s with no significant past medical history developed subarachnoid hemorrhage due to ruptured left middle cerebral artery aneurysm. On the ninth hospital day, he had a ruptured visceral aneurysm with segmental arterial mediolysis, and we successfully treated with transarterial embolization using metallic coils.

Mesenteric Artery Dissection and Wall-Thickening, Case Study and General Review

Mesenteric artery dissection (D) and wall-thickening (WT) are rare vasculopathies that can lead to serious complications. This is a single center analysis of all patients evaluated for mesenteric arterial (celiac, superior (SMA) and/or inferior mesenteric (IMA)) D and/or WT from January 1, 2000, to January 31, 2020 at our hospital. Among the 101 included patients, the average age was 55.6 ± 13.6 years, mostly affecting men (62%). There were 20 celiac artery D, 8 WT, 15 D with WT, 15 SMA D, 7 WT, 8 D with WT, one IMA D, two WT, and 25 with multiple arterial involvement. Primary etiologies included segmental arterial mediolysis (SAM) (n = 17), isolated D (n = 17), localized vasculitis of the gastrointestinal tract (LVGT) (n = 16), fibromuscular dysplasia (FMD) (n = 13), extension of thoracoabdominal aortic D (n = 12), and trauma (n = 12). Most (71%) patients presented with abdominal pain. Hypertension (55%), hyperlipidemia (33%) and tobacco use (31%) were prevalent. Management included conservative (22%), medical (47%), endovascular (19%), and/or open repair (12%) with high in-hospital survival (98%) and symptom relief (73%). Our paper complements the scarce literature addressing the diagnosis and management of rare mesenteric vasculopathies. Most patients improved with conservative management, reserving endovascular or surgical interventions for symptomatic patients with more complicated presentations.

Specific Features of Patients Under 40 Years Old With Small-to-Medium-Sized Arterial Deterioration

Background

Arterial deterioration is mostly caused by atherosclerosis, which progresses with age. However, we have observed serious backgrounds or etiologies in younger patients with non-atherosclerotic diseases and deterioration of small-to-medium-sized arterial lesions. Therefore, we aimed to identify the specific features of patients aged <40 years with deterioration of small-to-medium-sized arteries.

Methods

We selected patients who were admitted to our department from 1995 to 2019 with deterioration of small-to-medium-sized arteries (aneurysms, dissection, rupture, or arterial injury/damage) and focused on the cohort aged <40 years. We examined the backgrounds or etiologies of the patients including genetic and inflammatory diseases, which might have caused the arterial deterioration.

Results

Consequently, more than half (54.1%) of the patients aged <40 years had non-atherosclerotic comorbid diseases. However, the number of deteriorated arterial lesions was higher in patients aged <40 years than in patients aged ≥40 years (3.13 vs. 1.33 lesion/patient; P = 0.011). Furthermore, the data analysis of patients with multiple arterial lesions (≥3) revealed that the younger population tended to have more specific backgrounds or etiologies, notably Ehlers-Danlos syndrome and Behçet's disease. There were no differences in the all-cause mortality and cardiovascular disease-related mortality between patients aged <40 and ≥40 years (P = 0.89 and 0.29, respectively).

Conclusions

Over 50% of patients aged <40 years with deterioration of small-to-medium-sized arteries had non-atherosclerotic, specific clinical backgrounds or etiologies, including genetic and inflammatory diseases. In addition, they exhibited more arterial lesions than older patients.

A Single Center 8 Year Experience of Segmental Arterial Mediolysis Management

OBJECTIVE

Segmental Arterial Mediolysis (SAM) is a rare, poorly understood vasculopathy that involves vacuolization of the arterial wall, most commonly of the visceral arteries. There are no established therapeutic or monitoring guidelines for SAM, and intervention typically depends on patient presentation. The purpose of this study is to review the management and outcomes of patients with this rare vascular disease METHODS: Single center retrospective review of patients diagnosed with SAM between 2011 and 2019. Included were patients with radiological diagnosis of SAM. Demographic factors, past medical history, presenting symptoms, affected vessels, management, and lesion characteristics over time were collected. Demographic and periprocedural factors, and medical management strategies were compared for those who required operative intervention versus those managed non-operatively.

RESULTS

Thirty patients were included, 21 (70%) were male, mean age was 53.5 years (range: 35.7-72.2). Twenty-seven patients were managed non-operatively, 3 patients required surgical intervention. Patients who underwent operative intervention were more likely to present with pain >30 days (P < 0.05), and hemorrhage (P < 0.01). Abdominal pain was the most common presenting symptom (n = 24, 80%). Arterial dissection was the most common radiological finding at time of presentation (n = 20, 67%). The celiac artery and its branches were most often involved (n=22, 73%) followed by the superior mesenteric artery and its branches (n = 15, 50%). Non-operative management most often consisted of anti-hypertensive therapy (n = 13, 43%), antiplatelet agents (n = 17, 57%%), and lipid-lowering agents (n = 13, 43%), with 7 patients receiving all three. Six patients demonstrated confirmed resolution of lesions during surveillance imaging, with average time to resolution of 325.5 days.

CONCLUSIONS

Patients who underwent intervention for SAM presented with either mesenteric ischemia or pseudoaneurysm rupture. In patients that present without those conditions, medical management consisting of anti-hypertensives, antiplatelet agents, and lipid-lowering therapy was effective. Non operative management resulted in symptom resolution in all patients and surveillance imaging showed resolution of radiographic abnormalities in 6 patients out of 27 at less than one year.

A case presenting as fatal subarachnoid hemorrhage due to segmental arterial mediolysis associated with Crohn's disease

BACKGROUND

Segmental arterial mediolysis (SAM) is a rare arterial pathology and can cause rupture or dissection of the intracranial arterial wall. The etiology is unveiled, but vasospastic stimuli such as migraine are considered as a possible cause of SAM. We present the first case of subarachnoid hemorrhage (SAH) due to SAM associated with Crohn's disease and migraine, and discuss the possible contribution of Crohn's disease to the development of SAM besides migraine.

CASE DESCRIPTION

A 33-year-old man with Crohn's disease, which had been treated with adalimumab, repeatedly underwent 3-tesla magnetic resonance (MR) imaging and angiography for severe headache due to migraine and the subsequent development of fatigue in the left arm and both legs. At 7 months after the last MR imaging studies showing no abnormalities, he had a sudden onset of severe SAH, which was caused by rupture or dissection of the terminal portion in the right internal carotid artery. As his brain-stem reflexes were absent, the patient was conservatively treated and died 6 days after the ictus. By postmortem histopathological examination, SAM was diagnosed as the cause of SAH. Vasa vasorum was also observed around the rupture point.

CONCLUSIONS

Our case suggests that: 1) the formation of vasa vasorum may be an antecedent pathology for vessel rupture of the fragile arterial wall affected by SAM, and 2) vasospastic nature of both Crohn's disease and migraine may contribute to the development of intracranial SAM.

Segmental Arterial Mediolysis (SAM) Leading to Chronic Renal Insufficiency

Background

Segmental arterial mediolysis (SAM) is a rare self-limiting non-atherosclerotic, non-inflammatory vasculopathy. SAM typically affects the visceral arteries of the abdomen to include the celiac, mesenteric, and renal arteries. SAM has a favorable prognosis in most cases with an asymptomatic course but can have mortality rates as high as 50% due to acute aneurysmal rupture. Very few cases of adverse long-term sequelae involving SAM have been described, and this report of chronic kidney disease represents a sentinel case illustrating that chronic disease can and does occur as a result of SAM and should be investigated for at follow-up.

Case Presentation

In this case report, we describe a case of a 45-year-old male with erectile dysfunction but without any readily identifiable risk factors for chronic kidney disease (CKD) or vasculopathy, who presented with bilateral renal infarction and parenchymal infarcts due to SAM and who subsequently developed CKD at follow-up. We conduct a mini-literature review that discusses the pathogenesis of SAM in the context of vasospastic diseases, as well as compares the outcomes of observation-only, versus medical-management, versus endovascular-interventions in patients with SAM.

Conclusion

This is the first case to our knowledge of CKD occurring as an outcome of SAM without any preceding significant comorbidity, highlighting that whereas SAM is of itself rare and typically resolves, chronic disease can linger and should be evaluated for on follow-up. Further, we argue that radiological evidence of precursor vasospastic disease may exist in several locations apart from the index lesion and thus warrants wider whole-body radiographic exploration for lesions as an opportunity to prevent chronic sequelae as illustrated in this case report from occurring. Finally, a review of published case-series suggests that disease progression is less likely to occur after endovascular-intervention compared to observation-only or medical management and the risk of intervention vs conservative management should therefore be discussed with the patient.

Clinically Suspected Segmental Arterial Mediolysis of the Splanchnic Arteries: A Report of 2 Rare Cases

Case series

Patients: Female, 89-year-old • Male, 52-year-old

Final Diagnosis: Segmental arterial mediolysis

Symptoms: Abdominal pain • bleeding

Medication: —

Clinical Procedure: —

Specialty: Radiology

Natural History of Unruptured Visceral Artery Aneurysms Due to Segmental Arterial Mediolysis and Efficacy of Transcatheter Arterial Embolization: A Retrospective Multiinstitutional Study in Japan

OBJECTIVE. The purpose of this study was to clarify the natural history of unruptured visceral artery aneurysms due to segmental arterial mediolysis and the efficacy of transcatheter arterial embolization. MATERIALS AND METHODS. Patients with a pathologic or clinical diagnosis of visceral artery aneurysms due to segmental arterial mediolysis between 2005 and 2015 were enrolled. For patients with clinical diagnoses, images were collected and assessed by central radiologic review. To clarify the natural history of unruptured aneurysms, the morphologic changes were assessed. The efficacy and safety of transcatheter arterial embolization for aneurysms due to segmental arterial mediolysis were evaluated. RESULTS. Forty-five patients with 123 aneurysms due to segmental arterial mediolysis were enrolled. Among the 123 aneurysms, 70 unruptured aneurysms were evaluated for natural history. Forty-five of the 70 (64%) aneurysms had no change in morphology. Among the other 25 aneurysms, nine (13% of the 70) were reduced in size, 13 (19%) disappeared, and three (4%) were newly found at follow-up. Aneurysms of the middle colic artery were ruptured in 10 of 11 (91%) cases. Transcatheter arterial embolization was performed on 45 aneurysms and was successful in all cases but caused slight arterial injury in three cases (6.7%). CONCLUSION. At initial diagnosis, unruptured aneurysms due to segmental arterial mediolysis are likely to be stable or to resolve, but the risk of rupture of aneurysms of the middle colic artery appears high. Transcatheter arterial embolization is a useful treatment, but careful manipulation is necessary.

Ileocolic arterial aneurysm associated with segmental arterial mediolysis: A case report

OBJECTIVES

Segmental arterial mediolysis is a rare disease that most commonly affects the superior mesenteric artery among abdominal arteries. However, aneurysms involving the ileocolic arterial branch of the superior mesenteric artery are extremely rare. Here, we describe the treatment of a patient with an ileocolic arterial aneurysm suspected to have occurred secondary to segmental arterial mediolysis.

METHODS

We confirmed the diagnosis of ileocolic arterial aneurysm, which showed the characteristic "string-of-beads" appearance of the distal main trunk of the superior mesenteric artery on angiography. We performed endovascular coil embolization for the aneurysm, and for both the inflow and outflow vessels. After confirming that the aneurysm was no longer visible, the treatment was completed.

RESULTS

There were no clinical findings suspicious of ischemic enteritis or intestinal necrosis after embolization. We confirmed that the ileocolic arterial aneurysm was not observed on computed tomography angiography one month after treatment.

CONCLUSIONS

While development of an ileocolic arterial aneurysm associated with segmental arterial mediolysis is very rare, it is at a high risk of sudden rupture. Therefore, coil embolization is a useful intervention in such patients and can be implemented based on the size and morphology of the aneurysm.

Beyond Giant Cell Arteritis and Takayasu's Arteritis: Secondary Large Vessel Vasculitis and Vasculitis Mimickers

PURPOSE OF REVIEW

To provide an overview of mimickers of large vessel vasculitis (LVV), by the main presenting manifestation, i.e., systemic, vascular, and cranial manifestations.

RECENT FINDINGS

The main differential diagnoses in patients with giant cell arteritis (GCA) and Takayasu arteritis (TAK) presenting with systemic manifestations (i.e., fever, anorexia, weight loss, night sweats, arthralgia/myalgia, and/or increased inflammatory indexes) are neoplastic, infectious, or other inflammatory conditions. In patients with vascular manifestations (such as peripheral ischemia, vascular stenoses, or aneurysms), atherosclerosis and non-inflammatory vascular diseases should be excluded. In those presenting with predominant cranial symptoms (i.e., temporal headache, jaw claudication, scalp tenderness, transient or permanent vision loss), other causes of headache, cerebrovascular accidents, optic neuropathy, and neuromuscular syndromes need to be considered. The diagnosis of LVV maybe challenging, especially when patients present with atypical or incomplete clinical forms. In these cases, a multidisciplinary approach is strongly recommended.

A Case of Segmental Arterial Mediolysis: Hemoperitoneum with Hemorrhagic Shock due to Rupture of a Visceral Artery Aneurysm Following Subarachnoid Hemorrhage

Objective

Segmental arterial mediolysis (SAM) is a non-inflammatory and non-atherosclerotic vascular disease characterized by segmental medial defect/necrosis of muscular arteries as a result of mediolysis. SAM affects the visceral and intracranial arteries, and causes arterial dissection and aneurysm. We report a case of aneurysmal subarachnoid hemorrhage (SAH) followed by hemoperitoneum due to a ruptured visceral artery aneurysm.

Case Presentation

A 54-year-old man developed SAH from a ruptured anterior communicating artery aneurysm, which was clipped on the same day. Thereafter, he was treated to prevent cerebral vasospasm. Six days after onset, he developed acute anemia and his blood pressure decreased, suggesting hemorrhagic shock. Hemoperitoneum was detected on computed tomography and abdominal angiography was performed. Irregular and stenotic arterial findings, and an unusual aneurysm with contrast stasis were found in a branch vessel from the right gastroepiploic artery. SAM was diagnosed based on the clinical course and angiographic characteristics. Endovascular treatment consisted of embolization of the visceral artery aneurysm with liquid embolic material. after embolization, the vital signs stabilized and he recovered from shock. Acute treatment for SAH was continued. Although the patient did not develop vasospasm-related sequelae, he was transferred to the rehabilitation hospital 7 weeks after onset and his modified Rankin Scale score at 3 months after onset was 2.

Conclusion

Visceral artery aneurysm associated with SAM should be considered as the cause of hemoperitoneum with hemorrhagic shock during the acute phase of SAH.

A case of endovascular therapy for treating idiopathic arterial deteriorations of unknown etiology

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A 50-year-old patient presented with multiple idiopathic arterial deteriorations.

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He had a renal artery tear and a pseudoaneurysm of the left internal iliac artery.

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Previous direct intervention failed and we suspected vascular fragility.

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The two lesions were treated by simultaneously placing endografts.

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Endovascular treatment is a desirable option in the case of vascular fragility.

Introduction

Peripheral artery pseudoaneurysm as a consequence of arterial deterioration is relatively rare in young populations, who typically lack an atherosclerotic background. Such pseudoaneurysms are known to pose a risk of rupture, which is correlated with high mortality and morbidity rates. Pseudoaneurysms are more prone to rupture than true aneurysms are, as their vessel walls tear more easily. We present the case of a 50-year-old patient who had multiple arterial deteriorations.

Case presentation

The patient experienced backache, and computed tomography revealed a tear of the right renal artery, and a pseudoaneurysm of the left internal iliac artery. He had a history of graft replacement for the right superficial artery pseudoaneurysm, which had been occluded. Although various tests were performed for differential diagnosis, the etiology was unidentified. Considering the suspected vascular fragility and failure of previous direct intervention, these 2 lesions were treated by placing endografts simultaneously.

Discussion

We investigated various diseases causing vascular fragility in the reported case, such as vascular Behçet disease, vascular Ehlers-Danlos syndrome, fibromuscular dysplasia, and segmental arterial mediolysis. However, these were all excluded and the etiology remains unclear. Progress in endovascular techniques enables the use of minimally invasive treatment in patients with vascular fragility.

Conclusion

When vascular fragility may exist, endovascular treatment is a desirable option, as it can be performed repetitively and is less invasive.

Segmental arterial mediolysis: a commonly overlooked aetiology of acute abdominal pain

Segmental arterial mediolysis (SAM) is an uncommon condition and commonly missed diagnostic aetiology of acute abdominal pain, initially described in 1976. SAM is a non-inflammatory, non-atherosclerotic vasculopathy mostly involving the abdominal arteries with notable asymmetric involvement of the walls of the mesenteric arteries and their branches. Clinical presentation ranges from postprandial abdominal discomfort suggestive of mesenteric ischaemia to intra-abdominal bleeding. Pathophysiological explanation and prognosis of these cases are not well understood and therefore no clear guidelines for management exist. In this case report, we emphasise the imaging modalities used to reach the diagnosis and the management options available.

Natural history and management outcomes of segmental arterial mediolysis

BACKGROUND

Segmental arterial mediolysis (SAM) is a poorly understood, nonatherosclerotic, noninflammatory disease resulting from arterial medial degeneration. Patients may present with aneurysm, dissection, stenosis, or bleeding from visceral or renal arteries. Treatment algorithms are poorly characterized.

METHODS

A retrospective review of all patients diagnosed with SAM was performed at our institution. Patients were identified by established criteria that include clinical presentation in combination with radiographic and serologic findings. Demographics, presenting symptoms, diagnostic evaluation, management, and outcomes were reviewed.

RESULTS

There were 117 patients diagnosed with SAM between 2000 and 2016; 67.5% (n = 79) were male. Mean age was 52.7 years (range, 23.4-90 years); 69.2% (n = 81) presented with acute abdominal pain, 22.2% (n = 26) with flank pain, and 19.7% (n = 23) with back pain; 15.4% (n = 18) had abdominal pain longer than 30 days; 13.7% (n = 16) had acute hypertension, and 5.1% (n = 6) were hypotensive; 10.3% (n = 12) were asymptomatic. There were 93 (79.5%) dissections and 61 (52.1%) aneurysms. Hemorrhage was seen in 10 (8.5%). The celiac axis was affected in 54.7% (n = 64), renal arteries in 49.6% (n = 5 8), superior mesenteric artery in 43.6% (n = 51), and inferior mesenteric artery in 2.6% (n = 3). After diagnosis of SAM, aspirin was prescribed in 60.7% (n = 71). Statins were prescribed in 29.9% (n = 35). Antihypertensive medications were prescribed in 65% (n = 76), including beta blockers in 42.7% (n = 50); 40.2% (n = 47) of patients were prescribed anticoagulation. Interventions were performed in 26 (22%) patients; 13 had endovascular intervention only, 9 open surgery only, and 4 open and endovascular interventions. Of the 17 patients undergoing endovascular intervention, 19 procedures were performed, most commonly embolization (78.9% [n = 15]), followed by stenting (10.5% [n = 2]). Of the 13 patients undergoing open surgery, 14 procedures were performed, including arterial bypass (50% [n = 7]) and splenectomy with aneurysm ligation (15.4% [n = 2]). Other surgery involved thrombectomy (21.4% [n = 3]) and angioplasty (14.3% [n = 2]). Only 11.5% (n = 3) experienced a perioperative complication, including one hematoma, one abscess, and one death secondary to ongoing hemorrhage. Follow-up imaging was performed in 96.6% (n = 112). Mean follow-up was 1258 days (range, 2-5017 days). Of these, 27.7% (n = 31) had regression, 43.8% (n = 49) stability, and 28.6% (n = 32) progression. Average time between initial diagnosis and progression was 666 days.

CONCLUSIONS

SAM is an uncommon disease that may require intervention; it is therefore important that the vascular surgery community be aware of this disease. Follow-up imaging is required to monitor for disease progression.

Percutaneous Transgastric–Transpancreatic Treatment of a Dissecting Splenic Artery Pseudoaneurysm due to Segmental Arterial Mediolysis

Dissecting splenic artery pseudoaneurysm due to segmental arterial mediolysis (SAM) is a rare condition. We describe a case of direct percutaneous transgastric–transpancreatic thrombin injection into a dissecting splenic artery pseudoaneurysm due to SAM. The direct thrombin injection resulted in successful thrombosis of the pseudoaneurysm. At 1-month follow-up, the patient remained well with persistent thrombosis of the pseudoaneurysm.

Aortic dissection or spontaneous renal artery dissection, a rare diagnosis?

Spontaneous renal artery dissection (SRAD) is a rare entity causing muscle spasm due to acute low back pain, back pain, or flank pain symptoms or misleading clinical diagnosis such as renal colic. A 25-year-old Syrian male refugee presented to the emergency department with sudden onset of left-sided flank pain in the evening. Physical examination results were normal except left-sided costovertebral angle sensitivity. Abdominal, pelvic and thoracic contrast computed tomography angiography (CTA) was performed to evaluate aortic dissection, which was our urgent preliminary diagnosis. Left renal artery dissection was detected in CTA. The patient was treated with medical conservative treatment and spontaneous recovery was observed during the follow-up period. Early detection of SRAD in the emergency department can be difficult due to the fact that the clinical presentation is misleading.

Omental apoplexy: Unravelling the mystery

INTRODUCTION

To describe cases omental haemorrhage and to review the literature on this topic.

METHODS

We describe three cases of spontaneous omental haemorrhage and discuss various management strategies, in an attempt to provide direction for similar cases in the future.

RESULTS

A number of case reports of spontaneous or idiopathic omental haemorrhage exist in the literature. These cases are often attributed to an underlying vasculopathy, such as segmental arterial mediolysis (SAM). Appropriate resuscitation is paramount for best outcome. Severe bleeding may require surgery or transcatheter arterial embolisation, which is best performed early if required. Endovascular management using selective catheterisation of the bleeding vessel and embolisation is a minimally invasive alternative to emergent operative intervention. In the three cases we present, endovascular embolisation was performed in two patients, and surgical ligation in a third. Segmental arterial mediolysis is considered the likely aetiology in at least 2 of the 3 cases, based on imaging findings. No further episodes of haemorrhage occurred at follow-up (ranging from 6 months to 2 years).

CONCLUSIONS

Acute omental haemorrhage is a rare condition; however, it may be associated with significant morbidity and mortality. CT angiography is the imaging of choice. Management strategies include both endovascular and surgical intervention.

A Review of Primary Vasculitis Mimickers Based on the Chapel Hill Consensus Classification

Primary systemic vasculitides are rare diseases that may manifest similarly to more commonly encountered conditions. Depending on the size of the vessel affected (large vessel, medium vessel, or small vessel), different vasculitis mimics must be considered. Establishing the right diagnosis of a vasculitis mimic will prevent unnecessary immunosuppressive therapy.

Rare Mesenteric Arterial Diseases: Fibromuscular Dysplasia and Segmental Arterial Mediolysis and Literature Review

Fibromuscular dysplasia (FMD) and segmental arterial mediolysis (SAM) are noninflammatory, nonatherosclerotic arterial diseases that cause aneurysm, occlusion, and thromboses. These diseases are rarely seen in mesenteric arterial lesions; however, as they can be lethal if appropriate management is not provided, the accumulation of clinical information from cases is essential. We herein report the cases of a 57-year-old man diagnosed with FMD and a 63-year-old man diagnosed with SAM. We conclude that an early diagnosis with imaging modalities and clinical information followed by the appropriate treatment improves the prognosis of these arterial diseases.

A Ruptured Blood Blister-Like Aneurysm Associated with Intraperitoneal Hemorrhage due to Segmental Arterial Mediolysis: A Case Report and Literature Review

BACKGROUND

Segmental arterial mediolysis (SAM) is a rare non-atherosclerotic, noninflammatory vascular disease, characterized by mediolysis. We report an extremely rare case of subarachnoid hemorrhage (SAH) due to a ruptured blood blister-like aneurysm (BBA) of the internal carotid artery associated with SAM-related arteriopathy.

CASE DESCRIPTION

We experienced a case of SAH followed by intraperitoneal hemorrhage that occurred 12 days after the SAH onset. SAH was caused by a ruptured BBA of the internal carotid artery, which was treated by trapping with high-flow bypass. Intraperitoneal hemorrhage was caused by a rupture of a posterior inferior pancreaticoduodenal artery (PIPDA) aneurysm, which induced hypovolemic shock resulting in death in spite of endovascular internal trapping. Postmortem pathologic examination revealed that the PIPDA pseudoaneurysm was due to SAM.

CONCLUSIONS

We should pay attention to the association of SAM, which is a potentially life-threatening pathology when treating cerebral BBAs.

Hybrid Surgery for Multiple Visceral Artery Aneurysms: A Case Report

BACKGROUND

We present a case with multiple visceral artery aneurysms that were treated with a hybrid approach involving both surgical and endovascular treatment.

CASE REPORT

The patient was a 48-year-old female. She was diagnosed with multiple visceral artery aneurysms including 2 splenic artery aneurysms, celiac artery aneurysm, and bilateral renal artery aneurysms during an examination for loss of appetite. With regard to 2 splenic artery aneurysms, the proximal aneurysm was treated surgically, whereas the peripheral aneurysm that was located deeply in the abdomen was treated with coil embolization. The celiac artery aneurysm located at the bifurcation of the common hepatic artery and splenic artery, an intracranial aneurysm clip was used. The left and right renal aneurysms were resected and renal arteries were reconstructed surgically. The postoperative course was uneventful. The pathological diagnosis of all aneurysms was segmental arterial mediolysis. The reconstructed vessels were patent without stenosis or recurrence at 1 year after the operation.

CONCLUSIONS

Hybrid treatment involving surgical resection, endovascular coil embolization, and obliteration with clips was useful in the treatment of multiple visceral artery aneurysms.

Segmental arterial mediolysis

This article reports the case of a 51-year-old woman in whom brain MRI to follow up multiple sclerosis incidentally discovered an intramural hematoma in the extracranial internal carotid artery. MR angiography of the supra-aortic trunks and CT angiography of the aorta showed arterial dilations, aneurysms, dissections, and intramural hematomas in the internal carotid arteries, vertebral arteries, and arteries in the splanchnic territory. These findings raised suspicion of segmental arterial mediolysis. After 6 months of treatment with antiplatelet drugs, the arterial involvement resolved. Segmental arterial mediolysis is an uncommon disease; low clinical suspicion and radiologists' lack of knowledge about this entity mean that it can go undetected or be confused with other vasculitides. This report describes the most relevant pathophysiological findings and correlates them with the imaging findings.

Scleroderma renal crisis with coexisting segmental arterial mediolysis presenting as intraperitoneal bleeding: a case report

Background

Segmental arterial mediolysis is a rare nonarteriosclerotic and noninflammatory vascular disease that may cause intraperitoneal bleeding. Scleroderma renal crisis is a rare complication of systemic sclerosis, leading to severe hypertension and renal dysfunction. To the best of our knowledge, this is the first reported case of a patient with concurrent systemic sclerosis with scleroderma renal crisis and pathologically confirmed segmental arterial mediolysis.

Case presentation

We report a case of a 68-year-old Chinese woman diagnosed with systemic sclerosis who was found to have coexisting segmental arterial mediolysis. She presented with back pain, and massive intraperitoneal bleeding was detected by computed tomography. She underwent laparotomy, and the bleeding was found to originate from the gastroepiploic artery. The pathological examination demonstrated gastroepiploic arterial dissection caused by segmental arterial mediolysis. After surgery, she developed severe hypertension with hyperreninemia and progressive renal dysfunction. Given the risk factors of corticosteroid administration and the presence of anti-ribonucleic acid polymerase III antibody, she was diagnosed with scleroderma renal crisis. The patient was proved to have a very rare case of coexisting scleroderma renal crisis and segmental arterial mediolysis.

Conclusions

There is no known etiological connection between segmental arterial mediolysis and systemic sclerosis or scleroderma renal crisis, but it is possible that coexisting segmental arterial mediolysis and scleroderma renal crisis may have interacted to trigger the development of the other in our patient.

Significance of radiology in the diagnosis and management of ruptured left gastric artery aneurysm associated with acute pancreatitis: Case report

RATIONALE

Left gastric artery aneurysms are very rare which progresses into hemorrhagic shock and diagnosis is very challenging particularly in patients with acute pancreatitis and cholecystitis whose vitals become unstable suddenly.

PATIENT CONCERNS

A 72-year-old female has presented with severe progressing abdominal pain was treated with total parenteral nutrition for acute pancreatitis based on preliminary work up, but suddenly became unstable with dropping vitals over the ensuing 48 hours. Physical examination has a positive Murphy sign and appeared lethargic. She has no past history of any chronic systemic illness or malignancy.

DIAGNOSES

Ruptured left gastric artery aneurysm and left hepatic artery aneurysm with intraperitoneal hemorrhage associated with acute pancreatitis and cholecystitis.

INTERVENTIONS

Emergency interventional surgery was performed to embolize both the aneurysms and the giant aneurysmal sac of the left gastric artery was secured with a micrometallic occluding coil which eventually controlled the active hemorrhage.

OUTCOMES

The patient became stable and was discharged after 15 days without any recurrence or complications during the 6-month follow-up.

LESSONS

This case is a peculiar example of a missed diagnosis of left gastric artery aneurysm associated with acute pancreatitis and cholecystitis with deteriorating clinical condition. Exhaustive radiological investigations are necessary for early diagnosis correlating with presenting clinical situations. Radiologists should be familiar with the challenges in diagnosis and management.

Acute Dissection of the Middle Colic Artery Immediately after Endovascular Abdominal Aortic Aneurysm Repair: A Case Report

A 78-year-old man underwent endovascular abdominal aortic aneurysm repair (EVAR) for a true aortic aneurysm. He developed sudden abdominal pain 4 hr after EVAR. Angiography revealed a dissected aneurysm of the middle colic artery (MCA). Despite conservative treatment, follow-up computed tomography revealed an expanded aneurysm of the MCA. We therefore performed coil embolization of the dissected MCA to prevent a rupture of the aneurysm. There has never been a reported case of acute dissection of the MCA immediately after EVAR that was not caused by catheters. In this report, we discuss the possible underlying mechanisms and the optimal therapeutic strategy for this rare complication.

Diagnosis and management of fibromuscular dysplasia and segmental arterial mediolysis in gastroenterology field: A mini-review

The vascular diseases including aneurysm, occlusion, and thromboses in the mesenteric lesions could cause severe symptoms and appropriate diagnosis and treatment are essential for managing patients. With the development and improvement of imaging modalities, diagnostic frequency of these vascular diseases in abdominal lesions is increasing even with the small changes in the vasculatures. Among various vascular diseases, fibromuscular dysplasia (FMD) and segmental arterial mediolysis (SAM) are noninflammatory, nonatherosclerotic arterial diseases which need to be diagnosed urgently because these diseases could affect various organs and be lethal if the appropriate management is not provided. However, because FMD and SAM are rare, the cause, prevalence, clinical characteristics including the symptoms, findings in the imaging studies, pathological findings, management, and prognoses have not been systematically summarized. Therefore, there have been neither standard diagnostic criteria nor therapeutic methodologies established, to date. To systematically summarize the information and to compare these disease entities, we have summarized the characteristics of FMD and SAM in the gastroenterological regions by reviewing the cases reported thus far. The information summarized will be helpful for physicians treating these patients in an emergency care unit and for the differential diagnosis of other diseases showing severe abdominal pain.

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.

Segmental Arterial Mediolysis of Omental Arteries with Haemoperitoneum: Case Report with Embolization of the Left Omental Artery and Brief Review of Literature

Segmental arterial mediolysis of an omental artery is an exceptionally rare condition. A 69-year-old man presented with haemoperitoneum six days after being hospitalized due to pneumogenic sepsis. Computed tomography of the abdomen showed a short segment dilatation of an omental artery in the left upper abdomen, compatible with segmental arterial mediolysis. Angiographic examination revealed alterations of omental branches of the right gastroepiploic artery and an aneurysm of the left omental artery, both characteristic of segmental arterial mediolysis. Embolization of the left omental artery with use of N-butyl-2-cyanoacrylate was performed. The postinterventional course was uneventful with increase of haemoglobin levels and without symptoms of omental infarction. Transcatheter embolization in the setting of haemoperitoneum due to segmental arterial mediolysis of an omental branch is technically feasible and a valuable alternative to emergency operation.

Spontaneous hemoperitoneum resulting from segmental arterial mediolysis

Segmental arterial mediolysis is a rare but potentially life-threatening arteropathy of medium to large arteries that can be managed with endovascular treatment for patients who are hemodynamically unstable. We present a case of segmental arterial mediolysis in a 73-year-old woman who developed spontaneous hemoperitoneum in the emergency department after initially presenting with unrelated upper respiratory complaints. Her initial computed tomography revealed an aneurysm arising off the right hepatic artery. She was taken to the interventional radiology suite for embolization and multiple aneurysms along the right hepatic artery were identified that had the appearance of segmental arterial mediolysis. She initially stabilized but then developed acute renal failure and had a decrease in hemoglobin on postprocedure day 2. She was taken back to the angiography suite where multiple small left gastric and left hepatic trunk aneurysms were identified, with a small area of extravasation evident. The vessel was coiled from the liver to the origin of the left gastric artery. She was discharged and had a follow-up angiogram 2 months later, which showed interval development of an aneurysm to the distal right hepatic artery.

Segmental Arterial Mediolysis: Abdominal Imaging of and Disease Course in 111 Patients

OBJECTIVE

The purpose of this study is to identify the imaging characteristics of segmental arterial mediolysis (SAM) at presentation and establish the longitudinal course of disease.

MATERIALS AND METHODS

We retrospectively identified patients with SAM at a single institution from 2000 through 2015. Diagnosis was based on published guidelines with multidisciplinary consensus. Imaging studies obtained at initial evaluation were reviewed to evaluate imaging findings and vascular territory distribution. All subsequent follow-up imaging studies were reviewed to assess for progression, stability, or regression.

RESULTS

We identified 111 patients (79 men and 32 women; median age, 51 years) who met the diagnostic criteria for SAM. Abdominal pain was the most common presentation (74%), followed by flank pain (21%). SAM most commonly affected the renal arteries (47%), superior mesenteric artery (46%), celiac trunk (46%), hepatic artery (23%), iliac arteries (18%), and splenic artery (14%). The most common imaging findings were dissection (86%), aneurysm (57%), beading or webs (28%), occlusion (19%), and a rind or wall thickening (15%). The 247 available follow-up imaging studies for 97 patients (median follow-up, 12 months) showed progression in 19 patients (20%), with either stability or regression observed in the remaining patients.

CONCLUSION

SAM most commonly affects the renal arteries, superior mesenteric artery, and celiac artery. Dissections and aneurysms are the most common imaging findings. Follow-up imaging studies show stability or regression in most patients.

Nonatherosclerotic vascular causes of acute abdominal pain

BACKGROUND

To examine the epidemiology, treatments, and outcomes of acute symptomatic non-atherosclerotic mesenteric vascular disease.

METHODS

Subjects were reviewed over a six year period. Categories included embolism (EM), dissection (DI), and aneurysm (AN). Presentation, demographics, treatment and outcomes were compared.

RESULTS

46 patients were identified (EM:20, AN:15, DI:11). Age at presentation differed (EM: 66.3, AN 62.4, DI 54.6, p < .05). EM more likely affected the superior mesenteric artery (EM80%, AN20%, DI45%, p = .002), DI hepatic artery (EM20%, AN13%, DI55%, p < .05), and AN mesenteric branches (EM5%, AN47%, DI0%; p = .001). EM more likely had history of arrhythmia (EM40%, AN7%, DI0%, p,0.05) and diarrhea (EM30%, AN7%, DI0%, p < .05). Treatment was most often surgical in EM (EM85%, AN33%, DI9%, p < .001), endovascular in AN (EM5%, AN40%, DI 9%, p < .02), and conservative in DI (EM15%, AN 33%, DI82%, p < .05). In hospital mortality was infrequent (EM10%, AN7%, DI0%, p = ns). Mean hospital length of stay differed by mechanism (EM13.6days, AN9.2, DI2.3, p = .005). Median follow up was 61 months. Survival at 1, 3 and 5 years for emboli was 75%, 70% and 59%, for aneurysms 93%, 86%, and 77%, and for dissections 100% at all time points (p = .043 log rank).

CONCLUSIONS

Patients with EM, AN, and DI differ in age, anatomic distribution and method of treatment. The etiology significantly affects long term survival.

Segmental Arterial Mediolysis: An Unusual Case Mistaken to be a Strangulated Hernia

INTRODUCTION

Segmental arterial mediolysis (SAM) is a rare nonatherosclerotic, noninflammatory vasculopathy causing arterial wall necrosis that leads to strictures, dissections, and aneurysms, particularly in medium-sized abdominal arteries. Awareness of SAM is important because, unlike vasculitides, immunosuppressive treatment may worsen the disease process.

CASE

A 58-year-old man with multiple medical comorbidities presented with acute epigastric pain and a right incarcerated inguinal hernia that was interpreted as showing bowel strangulation on computed tomography. The hernia was unable to be reduced in the emergency department, so the patient was taken for open reduction by the surgical service. Intraoperatively, he was noted to have a ruptured superior mesenteric artery aneurysm. Conventional angiography demonstrated a bead-like appearance of several jejunal branches of the superior mesenteric artery, raising concern for a vasculitis. His hospital course included rheumatologic consultation, and initial recommendations were to start immunosuppressive therapy for treatment of polyarteritis nodosa. Further testing demonstrated normal antinuclear antibody, antineutrophil cytoplasmic antibodies, and complement levels. Due to a lack of systemic symptoms or signs and otherwise unremarkable laboratory evaluation, the patient ultimately was diagnosed with SAM and immunosuppressive therapy was halted.

DISCUSSION

Unexplained medium arterial stenosis, dissection, aneurysm, and hemorrhage should raise suspicion for possible SAM. The initial management approach should focus on treatment of the acute hemorrhage, usually involving endovascular stenting or coil embolization. Unlike vasculitides, SAM does not benefit from, and may actually be harmed by, immunosuppressive therapy.

CONCLUSIONS

Clinicians involved in the longitudinal care of emergency department patients should be aware of this rare clinical entity in order to initiate appropriate treatment.

Subarachnoid and intraperitoneal hemorrhage secondary to segmental arterial mediolysis: A case report and review of the literature

Background Segmental arterial mediolysis (SAM) is an uncommon or underdiagnosed arteriopathy that presents with life-threatening hemorrhage. SAM can affect the intracranial, spinal, and visceral arteries, with reported cases of concomitant intracranial and visceral hemorrhage. Case description We present the case of a 61-year-old male with concurrent subarachnoid and intraperitoneal hemorrhage caused by simultaneously bleeding posterior spinal artery and splenic artery pseudoaneurysms. The posterior spinal artery pseudoaneurysms were treated with selective injection of polyvinyl alcohol particles into the posterior spinal artery, while the splenic artery pseudoaneurysm was treated with Gelfoam embolization. The constellation of imaging, clinical, and laboratory features led to a presumptive diagnosis of SAM, which remains the only reported cause of concurrent neurovascular and visceral artery aneurysm rupture. Conclusion SAM is a key diagnostic consideration in cases of concomitant intracranial, spinal, and visceral artery aneurysm rupture.

Imaging and clinical findings in segmental arterial mediolysis (SAM)

Segmental arterial mediolysis (SAM) is an uncommon, non-atherosclerotic, non-inflammatory arteriopathy that tends to affect the medium-sized splanchnic branches of the aorta along with renal, carotid, cerebral, and coronary arteries. The clinical presentation ranges from asymptomatic to severe, life-threatening intra-abdominal hemorrhage and shock. SAM overlaps clinically and radiologically with other inflammatory vasculitides. This article describes the pathologic-radiologic correlation, imaging findings, and the management of the disease. Radiologists should be familiar with this disease entity as imaging plays a crucial role in the diagnosis.

Fatal hemoperitoneum due to segmental arterial mediolysis

Spontaneous hemoperitoneum due to vascular injury is a life-threatening condition mostly associated with aortic or splanchnic arterial disease, which stems from atherosclerotic, inflammatory, or infectious origin. However, in 1976, Slavin and Gonzales described a nonatherosclerotic arterial disease that may render aneurysmal formation predominantly in the splanchnic arterial bed. The clinical presentation is diverse, but abdominal pain and shock prevail. We report the case of a middle-aged man who presented a hemoperitoneum due to a middle colic artery aneurysm rupture and died after undergoing a surgical treatment attempt. The preoperative imaging study revealed the presence of a huge hematoma in the epiplon retrocavity, and abdominal free liquid as well as extensive arterial disease with multiple aneurysms. The autopsy findings included hemoperitoneum, hematoma in the upper left abdominal quadrant, the surgical ligature of the middle colic artery, and histologic features consistent with segmental arterial mediolysis. The authors call attention to this rare entity and highlight the autopsy as a fundamental examination to accurately reach this diagnosis.