The major clinical features of myocardial noncompaction are heart failure, 
arrhythmias, and thromboembolic events. Prominent myocardial trabeculae and deep 
recesses characteristic of myocardial noncompaction can cause stagnant blood 
flow and the formation of left ventricular clots. We describe the case of a 
62-year-old woman who presented with symptoms of heart failure secondary to left 
ventricular noncompaction. Transthoracic and transesophageal echocardiography 
revealed multiple left ventricular thrombi, which had formed despite the 
patient's long-term therapy with aspirin. Anticoagulative therapy should be 
considered for patients with myocardial noncompaction who also have risk factors 
for thromboembolism, such as atrial fibrillation, a history of systemic 
embolism, or severe left ventricular systolic dysfunction. However, chronic 
antiplatelet therapy may not sufficiently prevent clot formation in patients who 
have myocardial noncompaction and severe left ventricular systolic dysfunction.