We describe the case of a 66-year-old man with a thoracoabdominal aortic aneurysm, who presented with cardiac failure; he had complained of shortness of breath. A contrast-enhanced computed tomography scan and transthoracic echocardiography showed compression of the left atrium and ventricle by a giant thoracoabdominal aortic aneurysm. The cardiac failure resolved after early prosthetic graft replacement surgery.