Atrial myxomas are the most common primary cardiac tumors, comprising up to 80% of all primary tumors of the heart (1). It is widely admitted that these tumors originate from subendocardial multipotential mesenchymal cells (2). Anatomically, atrial myxomas are mostly pedunculated and soft, and which are in consistency with a smooth, villous, or irregular surface. Atrial myxomas predominantly occur between the third and the sixth decades of life and show a 2.05:1 female predominance (3). Over 75% of myxomas originate from the left atrium, 18% of them from the right atrium, while less than 5% are found in bilateral atrium (4). Clinical manifestations of atrial myxoma vary greatly and patients usually present one of the symptoms in the following tetrad: Arrhythmias, intracardiac flow obstruction, embolic phenomena and constitutional symptoms (5). Atrial myxomas are asymptomatic in ~10% of the affected individuals (6). In clinic, neurologic signs occur in 25–45% of myxoma patients, and may appear as the initial symptom in 12% individuals (7). Surgical resection is the most effective treatment and preventive intervention in atrial myxomas.

The neurological signs of atrial myxoma commonly result from ischemic cerebral infarction complications, which are found in 30–50% of patients with myxoma (8). Manifestation as haemorrhagic stroke is uncommon, and this seems to be related to the formation of cerebral aneurysms (9). The tumor type, size, location and mobility appear to be closely associated with embolism in patients with atrial myxomas (10). Cerebral infarction might recur for non-diagnosed and treated myxomas. The delayed neurological complications of myxomatous disease include oncotic aneurysms and myxomatous metastasis. They usually present with manifestations similar to cerebral vasculitis and infective endocarditis (3). Accordingly, echocardiography, computed tomography, and magnetic resonance imaging of the heart should be performed in patients with suspected stroke.

Studies of atrial myxoma and secondary brain infarction are generally small series and case reports. In this study, clinical cases of atrial myxoma-associated neurologic complications were assessed for morphology and clinical data, also summarizing their imaging characteristics.

Atrial myxoma is found in the left atrium in 75% of patients in the solid or papillary form (2). In this study, ages (age at onset of 30–60 years) and sex distribution (female predominance) of atrial myxoma cases corroborated previous reports (6,7). Neurological symptoms of atrial myxoma might appear before or at the time of primary tumor diagnosis. They were found in 16.9% of patients, a rate lower than previously reported (4,8).

In this study, ischemic cerebral infarction was the most commonly encountered neurologic complication of atrial myxoma. Although embolism is a relatively common precursor of cerebral infarction in the youth, the majority of existing reports merely describe isolated cases. The present series assessed 22 patients with neurological manifestations associated with myxoma, including 15 with ischemic cerebral infarction. These data differ from previous series, which showed TIA as the most frequent neurological presentation of atrial myxoma (9). Nevertheless, multiple studies found percentages of ischemic cerebral infarction similar to the present values (4,5,10). This discrepancy may be associated with different pathological characteristics of atrial myxomas. This study showed that myxomas with irregular surface were more prone to embolism. Fracturing of small myxoma fragments is considered to be responsible for embolic events. Indeed, the irregular surface contributes to myxoma fragmentation and increases interactive areas, resulting in embolism (5,11,12).

Additionally, oncotic aneurysms are late signs of atrial myxoma. In patients with cardiac myxoma, oncotic aneurysms are caused by metastatic emboli, which invade and disrupt the vessel wall (13,14). In the current study, 1 patient presented with recurrent cerebral infarction caused by a partially thrombosed 1.7 cm myxomatous oncotic aneurysm. Previous studies have examined endovascular embolization, chemotherapy, and radiation in the treatment of such aneurysms, and the findings are equivocal (15–20). Therefore, the optimal treatment of myxomatous oncotic aneurysms needs to be established.

Atrial myxoma causes cerebral infarction, but can be treated. In 22 cases in this series, neurological manifestations were found as initial sign of atrial myxoma. In 14/15 patients with cerebral infarction, tumor diagnosis occurred during the hospital stay, with surgical removal within 1 month. All patients were diagnosed by echocardiography, which was used routinely after a stroke of uncertain cause. There was no recurrence of atrial myxoma in the 22 subjects that underwent surgical treatment during follow-up (6 months to 12 years). Our findings advocate for early diagnosis and surgical resection of atrial myxoma before further embolic or cardiac complications occur.

In summary, atrial myxomas frequently present with cerebral infarction in individuals without known cardiovascular risk factors. The middle cerebral artery is more commonly concerned. Irregular surface of myxomas appears to be related to embolic events. Echocardiography could improve diagnosis and early treatment of atrial myxomas.