Oncotic Cerebral Aneurysms in a Case of Left Atrial Myxoma, Role of Imaging in Diagnostics and Treatment

Cerebral Myxomatous Aneurysms: Case Series and Systematic Review of Literature with Adequate Follow-Up Periods and Aneurysmal Wall Biopsy Results

BACKGROUND

Cerebral myxomatous aneurysms (CMA) are intracranial aneurysms caused by cardiac myxoma. The exact mechanism underlying their development has not yet been elucidated. And an optimal treatment method has not yet been established because of rarity of the disease. In addition, most existing reports have had a short follow-up period or lack of follow-up imaging test results. The aim of this study was to provide better insights into the course and treatment options of CMAs.

METHODS

We describe 4 CMA patients treated in our hospital and literature search was performed using PubMed and Embase databases. Keywords used were as follows: "cerebral myxomatous aneurysm", "myxomatous aneurysm", "cardiac myxoma", and "intracranial aneurysm". Only publications in English and related to this disorder with adequate follow-up periods and aneurysmal wall biopsy results were included. Clinical, radiological, pathological, and treatment characteristics were analyzed.

RESULTS

A total of 149 CMA cases were managed conservatively that included 9 enlargements, 6 regressions, and 134 stable aneurysms, which were identified for a total of 453.33 aneurysm years (1.91% per aneurysm year, 1.27% per aneurysm year, and 28.76% per aneurysm year, respectively). Poor outcome rate was high in cases with hemorrhage (either parenchymal or subarachnoidal hemorrhage) due to rupture of the CMA (46.67%, 7 out of 15). Thirteen cases had aneurysm biopsy results of which 11 showed tumor invasion on the aneurysm wall.

CONCLUSIONS

Even though the natural course of unruptured, benign-looking CMAs appears to be favorable, the presence or absence of viable tumor cells in the aneurysm may promote an unfavorable disease course. In the case of large, symptomatic, and enlarging CMAs, surgical, endovascular, or combined treatment should be considered as the mortality and morbidity due to rupture might be high.

Cerebral Aneurysms Caused by Atrial Myxoma-A Systematic Review of the Literature

Background: The association between cerebral aneurysms and left atrial myxoma is known but rare. We described its pathogenesis, clinical presentation, diagnostic findings and treatment using a systemic review of the literature. Methods: MEDLINE via PubMed was searched for articles published until August 2022 using the keywords "atrial myxoma", "cardiac myxoma" and "cerebral aneurysm". Results: In this review, 55 patients with multiple myxomas aneurysms were analyzed, and 65% were women. The average age when aneurysms were diagnosed was 42.5 ± 15.81; most patients were less than 60 years old (86%). Aneurysms could be found before the diagnosis, at the same time as cardiac myxoma, or even 25 years after resection of the atrial mass. In our review, the mean time to diagnoses was 4.5 years. Our review estimates that the most common symptoms were vascular incidents (25%) and seizures (14.3%). In 15 cases, variable headaches were reported. Regarding management strategies, 57% cases were managed conservatively as the primary choice. Conclusions: Although cerebral aneurysms caused by atrial myxoma are rare, the long-term consequences can be serious and patients should be monitored.

Delayed multiple intracranial aneurysms caused by left atrial myxoma: a case report and literature review

Intracranial aneurysm may appear even after the removal of the cardiac myxoma. However, the pathogenesis and treatment of such aneurysm lesions are not clear. The study aimed to explore the clinical and imaging manifestation, hypothetical pathogenesis, and therapy in one case of left atrial myxoma causing multiple intracranial aneurysms. A 14-year-old male displayed a 3-hour history of episodic loss of consciousness and right hemiplegia after a leapfrog-like movement. The myxoma was diagnosed by a combination of clinical examination, leading to the diagnosis of mitral dynamic obstruction with a Grade III mitral diastolic murmur and tumor plop; magnetic resonance imaging, revealing multiple ischemic sites in both semi-oval centers; and transthoracic echocardiography, demonstrating a mitral valve obstruction. The myxoma was removed surgically; however, computed tomography angiography showed multiple intracranial aneurysms in both middle cerebral arteries 18 months after resection of the atrial myxoma. After conservative treatment, the patient had no neurological dysfunction symptoms for 5 years after myxoma resection. His condition is relatively stable. In conclusion, resection of the atrial myxoma may eliminate the early neurological symptoms, but it cannot ensure the nonoccurrence of delayed intracranial aneurysms. The neoplastic process theory was favored for explaining the aneurysm development in this case. According to the specific conditions of the patient, a combination of open surgery, chemotherapy, radiotherapy, and coil embolization is recommended.

Atypical intracranial aneurysms: spectrum of imaging findings in computed tomography and magnetic resonance imaging

We aim to describe demographics, clinical presentation, and spectrum of CT and MRI features suggestive of atypical intracranial aneurysms. The imaging protocols used for the diagnosis of intracranial aneurysms were thoroughly reviewed, including different CT and MRI protocols. We classified atypical aneurysms according to their location, size, clinical presentation, and specific imaging features. Dissecting aneurysms are one of the causes of stroke in young adults that may show intimal flap and double lumen. Traumatic intracranial aneurysms are a rare but serious complication of head injuries. Mycotic aneurysms are small and multiple at distal branch points with a high risk of rupture. Aneurysms with vasculitis are fusiform with a wide neck at a non-branch point that may be associated with vessel wall enhancement. Atherosclerotic aneurysms are usually large fusiform that affect large arteries. Oncotic aneurysms are relatively rare. They were reported to occur in patients with left atrial myxoma. Our study represented a wide spectrum of atypical intracranial aneurysms with their detailed diagnostic imaging findings on MRI and CT including newly introduced MRI sequences, which greatly influenced early diagnosis and timely management.

Delayed intracranial aneurysm formation after cardiac myxoma resection: Report of two cases and review of the literature

Myxomas are slowly growing benign neoplasms and represent the most common tumor of the heart. Embolism from cardiac myxoma occurs in 30-45% of patients and in at least half of the cases cerebral arteries are affected leading mainly to embolic ischemic strokes and rarely to delayed intracranial aneurysm formation. We present two cases with delayed intracranial aneurysmal formation 14 years and 18 years after cardiac myxoma resection. To the best of our knowledge these two cases represent the longest time interval between aneurysm detection after complete cardiac myxoma resection with no recurrence confirmed by transesophageal echocardiogram. Our study also provides the longest clinical and radiological follow-up on this type of lesion.

The dynamic natural history of cerebral aneurysms from cardiac myxomas: A review of the natural history of myxomatous aneurysms

We describe two contrasting patients with multiple cerebral aneurysms and a previous history of resected cardiac myxomas with no cardiac recurrence on follow-up echocardiography. Both patients presented with stroke- like symptoms; one with a left visual defect and the other with right hemiplegia. Magnetic resonance imaging of the brain of both patients showed the presence of multiple cerebral aneurysms that was later confirmed on conventional angiography. Both patients' aneurysms were managed conservatively. Serial angiograms were performed during their follow-up, which spanned several years. One patient's aneurysms remained static while the evolution of the other patient's aneurysms displayed a dynamic quality with some increasing in size while others diminished. This is the first description in which some aneurysms progressed while others regressed simultaneously in the same patient. Aneurysms in patients with a history of cardiac myxoma can be active years after primary tumor resection and it is difficult to predict how they will develop. We reviewed the literature of all patients with multiple myxomatous aneurysms who were treated conservatively to better understand the natural history of this rare disease. Long-term follow-up of these patients may be necessary.