Via Research Recognition Day Program VCOM-Carolinas 2025

Case Reports

Case Report: Death Due to Ruptured Cerebral Aneurysm Associated with Multivessel Fibromuscular Dysplasia Mikaela Melnychuk, OMS-III, B.S., 1 Andy Wassum, M.D. 2 Edward Via College of Osteopathic Medicine – Carolinas, Spartanburg, South Carolina 1 and Pathology Consultants, Greenville, South Carolina 2 2. Institution Name, Dept., City, State. Co-authorship should be given to collaborators such as a Statistician, who have made intellectual contribution in terms of writing, Mentor should be named last in list. Introduction Imaging Discussion/Conclusion

Fibromuscular dysplasia (FMD) is an idiopathic group of noninflammatory and non-atherosclerotic vascular disease classically associated with renal artery stenosis in young women. FMD is typically considered a rare disease but may be underdiagnosed. 1,2 Clinical presentation of FMD varies depending on which vessels are affected. Symptoms include hypertension and abdominal bruit (renal artery); pulsatile tinnitus, migraine headache, and dizziness (cerebrovascular); or embolic events (aneurysm). 3 However, many of these symptoms are seen in more common disease processes such as atherosclerosis (Figure 1) which must be ruled out. Due to the supposed rarity of the disease, patients may have complications from FMD before its diagnosis. These complications include, dissection, occlusion, or aneurysm. While women are more likely to have FMD, complications due to FMD are disproportionately higher in men than women. 1,3 A 39-year-old Black male was found unresponsive at his residence. The patient had no significant past medical history; however, family history was notable for a ruptured cerebral artery aneurysm in his maternal uncle. Postmortem autopsy revealed a 0.4cm ruptured, saccular aneurysm on the anterior communicating artery leading to a dense subarachnoid hemorrhage. Coronary arteries showed a single focus of concentric wall thickening with significant narrowing of the lumen affecting the right coronary artery. The single focus in the coronary artery showed a nearly complete occlusion of the artery lumen by fibrous proliferation of the intimal layer (Figure 2) . Histopathological examination of the cerebral aneurysm revealed a loose, fibroplastic protrusion extending from a normal arterial wall (Figure 3) . Renal arterioles had narrowing by fibrous proliferation of the intimal layer of the vessel walls. These findings were all consistent with intimal fibroplasia. Report of Case

Diagnosis Historically, diagnosis and classification of FMD was based on histological examination but due to invasive procedures to obtain biopsy and technological advancements, diagnostic imaging is performed. 1,2,4 Imaging classification: • Multifocal FMD: Alternating stenosis/dilation with

Figure 1. Histopathologic specimen of atherosclerosis in a coronary artery. Eccentric atherosclerotic cholesterol plaque ( ) within tunica media layer. Hematoxylin and eosin (H&E), digital slide image, x40 magnification

“string -of- beads” appearance (Figure 4) • Focal FMD: Singular concentric stenosis

Figure 4. The “string -of- beads” finding on angiogram. Alternating pattern of stenosis and dilatation (black arrow ) . 4

Figure 2. Histopathologic specimen of right coronary artery. Concentric intimal fibroplasia of coronary artery; Predominant fibrotic expansion with area of proliferation ( ) of tunica intima (between the green arrows). Tunica media ( ) and tunica adventitia ( ) layers are intact. H&E staining, digital slide image, x40 magnification.

References complications. There are known genetic factors associated with FMD, 1,3 as evidenced in this case by the patient’s maternal uncle, who died from a ruptured cerebral aneurysm. It was recommended that direct family members consult their physicians to evaluate for further testing. Considerations Recognition of FMD is essential for prompt diagnosis and management, reducing the risk of potentially fatal Conclusions Histological classification: • Medial dysplasia • Intimal fibroplasia (Figures 2 & 3) • Adventitial hypoplasia Management • Medical: • Blood pressure control with angiotensin-converting enzyme inhibitor or angiotensin receptor blocker • Antiplatelet therapy (e.g., aspirin) • Avoid vasoconstrictive agents (e.g., triptans, ergots) for headaches/migraines • Surgical: • Revascularization • Monitoring: • Serum creatinine • Repeat imaging

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Figure 3. Histopathologic specimen of cerebral artery aneurysm . A. Cerebral artery leading into the aneurysm; Tunica media ( ) intact with a portion of cerebral aneurysm. B. Cerebral artery aneurysm with a small portion of intact cerebral artery on the left; Mixture of proliferative and fibrotic expansion of tunica intima with the absence of tunica media. H&E staining, digital slide images, x40 magnification.

2025 Research Recognition Day

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