Incidental finding of a left atrial thrombus during surgical management of a massive pulmonary embolism.

A 58-year-old male presented with a hemodynamically significant pulmonary embolism. Computed tomography angiogram revealed a saddle embolus in the main pulmonary artery with extensive clot burden affecting all lobes and right heart strain. Transthoracic echocardiogram displayed a dilated right ventricle with reduced systolic function. The patient was scheduled for pulmonary embolectomy. The intraoperative transesophageal echocardiogram (TEE) demonstrated a mobile left atrial thrombus that was missed on previous imaging. After removal of the thrombi, TEE showed a patent foramen ovale (PFO). The left atrial thrombus passed across the PFO secondary to increased right heart and pulmonary pressures.