An Unusual Cause of a Transient Ischemic Attack (TIA)

A 65 year-old Caucasian female had a transient ischemic attack manifested by slurred speech. The episode lasted 30 minutes and resolved. Past medical history was significant for hypertension controlled by hydrochlorothiazide. She was admitted to a hospital and treated with clopidogrel 300 mg loading dose, followed by 75 mg/day.

She underwent 2 D-echocardiography, which revealed a large golf ball shaped mass in the left atrium. Her hospital course was uneventful and she was transferred to a hospital in Minnesota that specializes in this operation. She was successfully treated with cardiopulmonary bypass and surgical excision.

Left atrial myxoma is a rare, non-cancerous tumor of the heart. About 75% of myxomas occur in the left atrium, usually beginning in the wall that divides the two upper chambers of the heart. The remainder are in the right atrium. Right atrial myxomas are sometimes associated with tricuspid stenosis and atrial fibrillation.

Myxomas occur at all ages-most commonly in the third to sixth decades of life and are more common in women. Most are sporadic; about 10% of myxomas are inherited by in autosomal dominant pattern (familial), so that one-half of children are affected. Myxoma is the most common benign cardiac tumor. Clinical findings include embolism, obstruction of left atrial emptying and constitutional symptoms. The most common symptom of myxoma is congestive heart failure, while embolic manifestations occur in 25-33% of patients, often as the first symptom.

Cardioembolic infarction is due to occlusion of an intracranial artery by an embolus from the heart; in the above case, a myxoma. Cardiac embolism accounts for ~20% of ischemic stroke cases in the US. Other conditions causing cardiac emboli include: atrial fibrillation and acute myocardial infarction (most commonly), followed by: valvular vegetations, rheumatic valvular disease, prolapsed mitral valve, endocarditis and cardiomyopathy.

The diagnosis of embolic stroke is best made in the presence of one of the above cardiac conditions. All patients with transient ischemic attack (TIA) or stroke should be questioned and examined for evidence of atrial arrythymias, recent MI, valvular disease, and cardiomyopathy. Myxoma is a potentially curable cause of embolism. If a patient presents with TIA, cerebral infarction or syncope, myxoma should be considered and an echocardiogram performed. There is a rule in medicine "if you don't think about it