Natural history and management outcomes of segmental arterial mediolysis

Segmental arterial mediolysis after fenestrated endovascular abdominal aortic aneurysm repair-A rare complication

Segmental arterial mediolysis (SAM) is a rare, noninflammatory, nonatherosclerotic condition that occurs commonly in mesenteric vessels. There are no known predisposing risk factors to the development of SAM. We present a case of a 67-year-old woman who presented with abdominal pain 2 days following discharge after an elective endovascular abdominal aortic intervention. Repeat imaging 2 days after readmission showed the presence of multiple new aneurysms involving the mesenteric vasculature. She underwent attempted endovascular embolization of the largest aneurysm. The postmortem and histopathologic examinations confirmed the diagnosis of SAM.

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.

Rheumatic masqueraders: mimics of primary vasculitis - a case-based review

INTRODUCTION

Vasculitis conditions are often serious and sometimes fatal diseases, therefore it is paramount to diagnose correctly and treat appropriately. Mimics of primary vasculitis can include either non-inflammatory syndromes or secondary vasculitis where the underlying etiology of the vasculitis is being driven by infection, malignancy, drug-effect or other.

AREAS COVERED

This review comprises six individual cases of vasculitis mimics. Each case is presented and the clinical, radiographic, and histological features that distinguish the case from primary vasculitis are highlighted. Key mimics in large, medium and small vessel vasculitis are outlined.

EXPERT OPINION

The diagnosis of vasculitis requires a comprehensive assessment of clinical, radiographic, and histologic features. Clinicians should be familiar with mimics of primary vasculitis conditions. In the case of non-inflammatory mimics, it is important to differentiate from primary vasculitides in order to avoid unnecessary and potentially harmful immunosuppression. For cases of secondary vasculitis, identification of the correct etiologic cause is critical because treatment of the underlying stimulus is necessary for successful management and outcomes.

From Fibromuscular Dysplasia to Arterial Dissection and Back

Fibromuscular dysplasia (FMD) is an idiopathic and systemic non-inflammatory and non-atherosclerotic arterial disease. Fifteen to 25% of patients with FMD present with arterial dissection in at least one arterial bed. Conversely, a substantial number of patients with renal, carotid, and visceral dissection have underlying FMD. Also, while few patients with FMD develop coronary artery dissection, lesions suggestive of multifocal FMD have been reported in 30-80% of patients with spontaneous coronary artery dissection (SCAD), and the relation between these two entities remains controversial. The frequent association of FMD with arterial dissection, both in coronary and extra-coronary arteries raises a number of practical and theoretical questions: (i) Are FMD and arterial dissections two different facets of the same disease or distinct though related entities? (ii) Is SCAD just a manifestation of coronary FMD or a different disease? (iii) What is the risk and which are predictive factors of developing arterial dissection in a patient with FMD? (iv) What proportion of patients who experienced an arterial dissection have underlying FMD, and does this finding influence the risk of subsequent arterial complications? In this review we will address these different questions using fragmentary, mostly cross-sectional evidence derived from large registries and studies from Europe and the United States, as well as arguments derived from demographics, clinical presentation, imaging, and when available histology and genetics. From there we will derive practical consequences for nosology, screening and follow-up.

Endovascular treatment of an isolated iliac artery aneurysm associated with segmental arterial mediolysis

Segmental arterial mediolysis is a noninflammatory nonatherosclerotic vasculopathy of uncertain etiology characterized by dissection and/or aneurysm formation. It affects medium-to-large arteries, primarily the celiac, superior mesenteric, and renal arteries. Iliac involvement is rare, and its specific treatment has not been described. We detail a patient who presented with intrabdominal hemorrhage from a ruptured right colic artery aneurysm. He underwent transcatheter arterial embolization followed by right hemicolectomy. Histopathology confirmed the diagnosis of segmental arterial mediolysis. Endovascular treatment of a 3-cm iliac artery aneurysm was performed 18 months later. There was successful exclusion of the aneurysm demonstrated on computed tomography angiography at 10 years.

Hepatic segmental arterial mediolysis: A case report and brief literature review

Key Clinical message

When evaluating patients with abdominal pain, it is important to consider SAM in the differential diagnosis, along with vasculitis, fibromuscular dysplasia (FMD), atherosclerosis, mycotic aneurysms, and cystic medial degeneration.

Abstract

Segmental arterial mediolysis (SAM) is a rare arteriopathy which is an under-recognized and commonly missed diagnosis of abdominal pain. We report a case of a 58-year-old female who presented with abdominal pain and was misdiagnosed with a urinary tract infection. The diagnosis was made with CTA and managed with embolization. Despite appropriate intervention and close hospital monitoring, further complications were inevitable. We conclude that though literature has shown better prognosis and even complete resolution after medical and/or surgical intervention, close follow up and monitoring is needed to avoid unexpected complications.

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.

Surgical Excision of a Contained Rupture of an Inferior Mesenteric Aneurysm

Inferior mesenteric artery (IMA) aneurysms represent the minority of visceral aneurysm presentations. A 57-year-old female was admitted with a symptomatic IMA aneurysm secondary to atherosclerotic disease. She was treated with open excision which revealed a contained ruptured of a true aneurysm. This case highlights the challenges of an accurate preoperative diagnosis of IMA aneurysm and the correct position of the recent guidelines on visceral aneurysms issued by the Society of Vascular Surgery (SVS).

A case report of an isolated superior mesenteric artery dissection caused by childbirth

Background

The isolated superior mesenteric artery dissection (SMAD) is a rare and sporadic cause of acute abdominal pain. It most frequently affects male patients in their fifth to sixth decades, while our patient was a young woman who delivered a baby before the onset of abdominal pain. Possible risk factors for SMAD include hypertension, arteriosclerosis, abnormalities in elastic fibres, trauma, and pregnancy. In our case, delivery was suggested as a risk factor, which has not been reported previously.

Case presentation

A 27-year-old woman complained of acute severe upper abdominal pain and vomiting for 2 days after delivery. The patient had no significant medical history. Physical examination revealed epigastric mild tenderness. All routine blood tests, blood coagulation analysis, liver function tests and abdomen computed tomography showed no remarkable findings. Computed tomography angiography revealed a marked dissection 3.5 cm below the superior mesenteric artery ostium. Since distal blood flow existed and the patient was in a puerperal state with no evidences of mesenteric ischemia, she was managed conservatively, including intestinal rest by fasting, parenteral nutritional support and antibioticis, without anticoagulants or antiplatelet agents. Fortunately, she recovered smoothly and had no recurrence.

Conclusions

SMAD is a rare and sporadic cause of acute abdominal pain that occurs in young women after delivery.

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.

Ruptured Left Gastric Artery Aneurysm Associated with Fibromuscular Dysplasia

Background: Fibromuscular dysplasia is a non-inflammatory, non-atherosclerotic vascular disease that commonly affects renal and carotid arteries but involvement of virtually any vascular territory has been observed.Research Design/ Study sample: This is a case report of a ruptured left gastric artery aneurysm as the first presentation of fibromuscular dysplasia.Data collection: After written consent from the patient, relevant clinical notes and imaging were retrospectively reviewed and critically analysed.Purpose: This case reiterates the importance of considering fibromuscular dysplasia as an uncommon cause of visceral artery aneurysms. In addition, this case shows that the impact of visceral artery vasospasm on endovascular access should not be underestimated and subsequent attempts can be successful after a period of resuscitation.Results: After initial difficulty in endovascular treatment due to visceral vasospasm, the case was successfully managed with with staged open ligation and endovascular embolization after a period of resuscitation.Conclusions: FMD is an important differential diagnosis to consider in cases of visceral aneurysms.

Beyond Atherosclerosis and Fibromuscular Dysplasia: Rare Causes of Renovascular Hypertension

Renovascular hypertension is one of the most common forms of secondary hypertension. Over 95% of cases of renovascular hypertension are due either to atherosclerosis of the main renal artery trunks or to fibromuscular dysplasia. These two causes of renal artery stenosis have been extensively discussed in recent reviews and consensus. The aim of the current article is to provide comprehensive and up-to-date information on the remaining causes. While these causes are rare or extremely rare, etiologic and differential diagnosis matters both for prognosis and management. Therefore, the clinician cannot ignore them. For didactic reasons, we have grouped these different entities into stenotic lesions (neurofibromatosis type 1 and other rare syndromes, dissection, arteritis, and segmental arterial mediolysis) often associated with aortic coarctation and other arterial abnormalities, and nonstenotic lesions, where hypertension is secondary to compression of adjacent arteries and changes in arterial pulsatility (aneurysm) or to the formation of a shunt, leading to kidney ischemia (arteriovenous fistula). Finally, thrombotic disorders of the renal artery may also be responsible for renovascular hypertension. Although thrombotic/embolic lesions do not represent primary vessel wall disease, they are characterized by frequent macrovascular involvement. In this review, we illustrate the most characteristic aspects of these different entities responsible for renovascular hypertension and discuss their prevalence, pathophysiology, clinical presentation, management, and prognosis.

Beyond Atherosclerosis and Fibromuscular Dysplasia: Rare Causes of Renovascular Hypertension

Renovascular hypertension is one of the most common forms of secondary hypertension. Over 95% of cases of renovascular hypertension are due either to atherosclerosis of the main renal artery trunks or to fibromuscular dysplasia. These two causes of renal artery stenosis have been extensively discussed in recent reviews and consensus. The aim of the current article is to provide comprehensive and up-to-date information on the remaining causes. While these causes are rare or extremely rare, etiologic and differential diagnosis matters both for prognosis and management. Therefore, the clinician cannot ignore them. For didactic reasons, we have grouped these different entities into stenotic lesions (neurofibromatosis type 1 and other rare syndromes, dissection, arteritis, and segmental arterial mediolysis) often associated with aortic coarctation and other arterial abnormalities, and nonstenotic lesions, where hypertension is secondary to compression of adjacent arteries and changes in arterial pulsatility (aneurysm) or to the formation of a shunt, leading to kidney ischemia (arteriovenous fistula). Finally, thrombotic disorders of the renal artery may also be responsible for renovascular hypertension. Although thrombotic/embolic lesions do not represent primary vessel wall disease, they are characterized by frequent macrovascular involvement. In this review, we illustrate the most characteristic aspects of these different entities responsible for renovascular hypertension and discuss their prevalence, pathophysiology, clinical presentation, management, and prognosis.

Beyond Atherosclerosis and Fibromuscular Dysplasia: Rare Causes of Renovascular Hypertension

Renovascular hypertension is one of the most common forms of secondary hypertension. Over 95% of cases of renovascular hypertension are due either to atherosclerosis of the main renal artery trunks or to fibromuscular dysplasia. These two causes of renal artery stenosis have been extensively discussed in recent reviews and consensus. The aim of the current article is to provide comprehensive and up-to-date information on the remaining causes. While these causes are rare or extremely rare, etiologic and differential diagnosis matters both for prognosis and management. Therefore, the clinician cannot ignore them. For didactic reasons, we have grouped these different entities into stenotic lesions (neurofibromatosis type 1 and other rare syndromes, dissection, arteritis, and segmental arterial mediolysis) often associated with aortic coarctation and other arterial abnormalities, and nonstenotic lesions, where hypertension is secondary to compression of adjacent arteries and changes in arterial pulsatility (aneurysm) or to the formation of a shunt, leading to kidney ischemia (arteriovenous fistula). Finally, thrombotic disorders of the renal artery may also be responsible for renovascular hypertension. Although thrombotic/embolic lesions do not represent primary vessel wall disease, they are characterized by frequent macrovascular involvement. In this review, we illustrate the most characteristic aspects of these different entities responsible for renovascular hypertension and discuss their prevalence, pathophysiology, clinical presentation, management, and prognosis.

Beyond Atherosclerosis and Fibromuscular Dysplasia: Rare Causes of Renovascular Hypertension

Renovascular hypertension is one of the most common forms of secondary hypertension. Over 95% of cases of renovascular hypertension are due either to atherosclerosis of the main renal artery trunks or to fibromuscular dysplasia. These two causes of renal artery stenosis have been extensively discussed in recent reviews and consensus. The aim of the current article is to provide comprehensive and up-to-date information on the remaining causes. While these causes are rare or extremely rare, etiologic and differential diagnosis matters both for prognosis and management. Therefore, the clinician cannot ignore them. For didactic reasons, we have grouped these different entities into stenotic lesions (neurofibromatosis type 1 and other rare syndromes, dissection, arteritis, and segmental arterial mediolysis) often associated with aortic coarctation and other arterial abnormalities, and nonstenotic lesions, where hypertension is secondary to compression of adjacent arteries and changes in arterial pulsatility (aneurysm) or to the formation of a shunt, leading to kidney ischemia (arteriovenous fistula). Finally, thrombotic disorders of the renal artery may also be responsible for renovascular hypertension. Although thrombotic/embolic lesions do not represent primary vessel wall disease, they are characterized by frequent macrovascular involvement. In this review, we illustrate the most characteristic aspects of these different entities responsible for renovascular hypertension and discuss their prevalence, pathophysiology, clinical presentation, management, and prognosis.

A case of segmental arterial mediolysis with subarachnoid hemorrhage due to anterior cerebral artery dissection followed by internal carotid artery dissection

Background:

Segmental arterial mediolysis (SAM) causes subarachnoid hemorrhage (SAH) due to intracranial aneurysm rupture and arterial dissection. We encountered a case of SAM-related SAH due to ruptured dissection of the A1 segment of the anterior cerebral artery concomitant with internal carotid artery (ICA) dissection.

Case Description:

A 53-year-old man presented with SAH due to a ruptured right A1 dissecting aneurysm. The aneurysm was trapped; however, 7 days after the onset of SAH, he experienced right hemiparesis and aphasia. Angiography showed left ICA dissection; urgent carotid artery stenting was performed, leading to symptom improvement. Abdominal computed tomography angiography showed aneurysms of the celiac and superior mesenteric arteries. He was diagnosed with SAM based on clinical, imaging, and laboratory findings.

Conclusion:

In the acute phase of SAM-related SAH, cerebral ischemia could occur due to both cerebral vasospasm and intracranial or cervical artery dissection.

Visceral Artery Aneurysms Embolization and Other Interventional Options: State of the Art and New Perspectives

Visceral artery aneurysms (VAAs) are rare, usually asymptomatic and incidentally discovered during a routine radiological examination. Shared guidelines suggest their treatment in the following conditions: VAAs with diameter larger than 2 cm, or 3 times exceeding the target artery; VAAs with a progressive growth of at least 0.5 cm per year; symptomatic or ruptured VAAs. Endovascular treatment, less burdened by morbidity and mortality than surgery, is generally the preferred option. Selection of the best strategy depends on the visceral artery involved, aneurysm characteristics, the clinical scenario and the operator's experience. Tortuosity of VAAs almost always makes embolization the only technically feasible option. The present narrative review reports state of the art and new perspectives on the main endovascular and other interventional options in the treatment of VAAs. Embolization techniques and materials, use of covered and flow-diverting stents and percutaneous approaches are accurately analyzed based on the current literature. Visceral artery-related considerations and targeted approaches are also provided and discussed.

A case of black esophagus with duodenal involvement

Black esophagus is a rare condition referred from acute necrosis of the esophagus, with characteristic endoscopic finings of circumferential black appearance of the mucosa. Black esophagus is associated with systemic dysfunction, such as massive bleeding, or severe dehydration. Although the duodenal mucosa is also susceptible to ischemia, reports of black esophagus with duodenal involvement, such as bleeding or perforation, are limited. Here, we present the case of a 61-year-old male who developed the typical black esophagus with duodenal involvement following severe dehydration. The patient was treated conservatively and recovered from the acute phase. In the chronic stage, transthoracic esophagectomy was performed because of esophageal stricture, and the patient then returned to his daily life. Although the etiological mechanism of acute esophageal necrosis is unknown, it is thought to be associated with the presence of an underlying severe systemic condition. Our case is not exceptional for these systemic conditions demonstrating extreme dehydration. However, it remains unclear why our case showed duodenal involvement. Although the reason is unknown, the presence of a celiac aneurysm located near the bifurcation to duodenal blood flow might explain the impaired blood flow to the duodenum.

Biphasic clinical course of a ruptured right gastric artery aneurysm caused by segmental arterial mediolysis: a case report

BACKGROUND

Gastric artery aneurysms are rarely caused by segmental arterial mediolysis (SAM), a condition that often involves multiple vessels. The clinical course of SAM after vessel rupture may vary depending on the involved vessels. For example, the "double-rupture phenomenon" observed following the rupture of the splenic artery aneurysm manifests as a biphasic and relatively slow clinical course. Even in cases of rupture of gastric artery aneurysm, the double-rupture phenomenon has only been reported in two cases so far. However, the rupture was not caused by SAM in either case. Herein, we present the apparent first case of a right gastric artery (RGA) aneurysm rupture caused by SAM that presented with a biphasic clinical course, possibly due to the double-rupture phenomenon.

CASE PRESENTATION

A 54-year-old woman was transferred to the emergency department with severe abdominal pain and a cold sweat for a duration of 3 h. She had developed mild abdominal pain and nausea 3 days earlier. Her vital signs were stable. Physical examination revealed tenderness in the epigastric area. Abdominal contrast-enhanced computed tomography revealed an RGA aneurysm with contrast media extravasation. A diagnosis of hemoperitoneum following a ruptured RGA aneurysm was made, and the patient underwent angiography. However, this modality did not reveal any extravasation from the RGA due to an interruption in the peripheral branch of the artery. Nevertheless, to prevent major bleeding, we performed coil embolization at the point of interruption in the RGA, which we suspected to be a ruptured aneurysm. A distal gastrectomy with Roux-en-Y reconstruction for aneurysm resection was performed the following day. There were no postoperative complications, and the patient was discharged 17 days after surgery. Histologically, the RGA demonstrated multiple vacuoles in the medial muscle layer, which were characteristic of SAM.

CONCLUSIONS

An RGA aneurysm rupture should be considered a differential diagnosis in patients presenting with hemoperitoneum with a slow or biphasic clinical course.

Spontaneous visceral artery dissections in otherwise normal arteries: Clinical features, management, and outcomes compared with fibromuscular dysplasia

OBJECTIVE

Visceral artery dissection with otherwise normal-appearing arteries (VADNA), diagnosed on imaging and suggestive of segmental arterial mediolysis, is a poorly understood disease entity. Study objectives were to define the clinical features, management, and outcomes of patients with VADNA compared with patients with fibromuscular dysplasia (FMD).

METHODS

In this single-center retrospective cohort study, consecutive patients with a diagnosis of VADNA or FMD evaluated in the Mayo Clinic Gonda Vascular Center (January 1, 2000-April 1, 2017) were identified. Patient demographics, symptom presentation, management, composite adverse arterial events (recurrent arterial dissection, stroke or transient ischemic attack, myocardial infarction, mesenteric or renal infarction, or need for revascularization), and overall survival were compared between VADNA and FMD patients.

RESULTS

There were 103 VADNA patients (age [mean ± standard deviation], 51.7 ± 11.0 years; 27.9% female) and 248 FMD controls (49.8 ± 8.9 years; 81.8% female) identified. The most common symptom for VADNA patients was abdominal or flank pain (80.6%). For FMD, chest pain, headache, and dizziness were more frequent presenting complaints. The median follow-up was longer for VADNA patients (42 months; interquartile range, 9-76 months) compared with FMD patients (19 months; interquartile range, 0.6-52 months; P < .001). During this time interval, there were twofold more composite arterial events in the VADNA group compared with the FMD group (17% vs 8.1%; P = .01). This difference was primarily driven by recurrent dissections. All-cause mortality was low and similar for both groups (3.8% vs 0.4%; P = .10).

CONCLUSIONS

VADNA patients carry a higher risk of recurrent arterial events compared with those with FMD. This difference was primarily driven by recurrent dissections.