A 77-year-old woman fell and fractured her ankle. She has spent most of her time in bed for the past 16 days. She develops sudden chest pain, dyspnea, and diaphoresis. On examination, she has left thigh swelling and tenderness. A chest CT shows areas of decreased attenuation in the right and left pulmonary arteries. A day later she has difficulty speaking. MR angiography shows focal occlusion of a left middle cerebral artery branch. Which of the following cardiac abnormalities is she most likely to have?
This is the infamous "paradoxical embolus" that has appeared far more often in question sets than in real life. She started with thrombophlebitis that led to pulmonary embolism, but there must be an explanation for the "stroke" that then occurred. Pulmonary emboli can obstruct the pulmonary arterial circulation, raising right atrial pressure, and opening a patent foramen ovale that normally remains closed because of higher left atrial pressure. The remaining choices do not explain pulmonary thromboembolism. A left atrial myxoma can embolize to the brain; lesions of endocarditis are most often on the left side of the heart and could produce cerebral emboli; a ventricular aneurysm is virtually always on the left side of the heart because it results from a healed infarction, and can be filled with mural thrombus that can embolize.
Atrial myxoma
Infective endocarditis
Nonbacterial thrombotic endocarditis
Patent foramen ovale
C.V.S