
Despite initial clinical suspicion of recurrence of her phyllodes
breast tumour with metastases, the final pathology was indicative
of a malignant solitary fibrous tumour.
Discussion
Approximately 20% of ischemic strokes are thought to be
cardioembolic in nature.
1
Features on clinical presentation suggestive
of cardioembolism include: decreased level of consciousness,
maximum severity of symptoms at onset with quick recovery of
deficits, symptoms involving multiple vascular territories of the
brain and the presence of non-central nervous system emboli.
Cardiac sources of cerebral emboli include valvular disease, left
atrial or ventricular thrombi, and cardiac tumours. Paradoxical
emboli may occur when there is reversal of flow through a patent
foramen ovale, atrial or ventricular septal defect.
1
Primary cardiac tumours are uncommon with rates reported
between 0.001–0.28%.
2–4
Over 75% of primary cardiac tumours
are benign. Secondary cardiac tumours are more common;
2.3–18.3% of patients with a primary neoplasm have cardiac
metastases on post-mortem examination. Secondary cardiac
tumours may arise from extension of a primary tumour or are
metastastic lesions from extracardiac malignancies.
3,5
Malignancies
which most commonly metastasize to the heart and pericardium
include mesothelioma, lung adenocarcinoma, melanoma, breast
carcinoma and lymphoproliferative neoplasms.
3,6,7
Clinical
manifestations of cardiac tumours vary depending on tumour
location. Patients may present with chest pain, heart failure,
pericardial effusion, or arrhythmia. Cardioembolic stroke as
a presenting feature of a cardiac tumour is an extremely rare
occurrence.
3,6
Solitary fibrous tumours (SFTs) are neoplasms of spindle
cells, which originate from mesenchymal cells. SFTs are usually
Case
A 78-year-old woman presented to the emergency department
with a 3-week history of ataxia and diplopia. Her past medical
history was significant for surgical resection of a phyllodes
breast tumour with no known recurrence of disease. Physical
examination revealed a left cranial nerve III palsy, ataxia and
left-sided weakness. A non-contrast computed tomography
(CT) head demonstrated multifocal subacute infarcts in the
frontoparietal, posterior temporal and occipital regions. A
transthoracic echocardiogram showed no evidence of an
intracardiac mass.
The patient developed recurrent generalized seizures
during her hospitalization. Magnetic resonance imaging of the
head confirmed multifocal acute ischemic infarcts suggestive
of a cardio-embolic source. CT of the chest demonstrated a 3.3
cm bi-lobed atrial mass on the posterior wall of the left atrium,
extending into the right inferior pulmonary vein and encasing
the right bronchus intermedius (Figure 1). Several nodules in
the peripheral branches of the pulmonary vein were also present.
A transesophageal echocardiogram confirmed the presence of a
large 2.7 × 1.8 × 0.8 cm mobile echogenic mass attached to the
posterior left atrial wall which was not seen on the transthoracic
imaging (Figure 2).
The patient opted for non-acute management of her disease
and died twomonths later. A limited autopsy revealed a 5 × 4
× 3 cm malignant solitary fibrous tumour in the left atrium
invading the left ventricle, interventricular septum and epicardial
fat (Figure 3). The tumour also extended into the pulmonary
vein and infiltrated the vessel wall. Multiple branches of the
pulmonary vein were filled with emboli-like tumour nodules.
The tumour demonstrated areas of hypercellularity, necrosis, and
high mitotic activity, consistent with a high-grade malignancy.
Figure 1. Computed tomography of the chest demonstrating a bi-lobed atrial mass on the posterior wall of the left atrium measuring 3.3 cm and extending
into the right inferior pulmonary vein.
Canadian Journal of General Internal Medicine
Volume 13, Issue 4, 2018 29
Chan et al.