1Department of Clinical Laboratory, Sapporo City General Hospital, 2Department of Cardiovascular Medicine, Sapporo City General Hospital, 3Department of Health Sciences, Hokkaido University School of Medicine
We report a 29-year-old woman who presented with clinical features of acute pulmonary embolism. She was obese and took oral contraceptives, which she had obtained by personal import over the Internet. Transthoracic echocardiography revealed right ventricular pressure overload on the first day. On the second day, transthoracic echocardiography showed a serpentine thrombus trapped across the patent foramen ovale (PFO) protruding into the right and left atria. After the appearance of sudden hypoxemia on the third day, transesophageal echocardiography demonstrated right atrial enlargement, and a small right-to-left shunt through a PFO without any intracardiac thrombus. Computed tomography suggested massive thrombi in both the superior and inferior venae cavae. We chose anticoagulation and thrombolytic therapy rather than surgical thrombectomy. We thought elevated right-chamber pressure due to pulmonary hypertension favored the establishment of a right-to-left shunt, and that a long thrombus was temporarily trapped across the foramen ovale and finally caused recurrent pulmonary embolism. Although PFO has been reported to be an important predictor of adverse outcome in patients with pulmonary embolism, the patient recovered rapidly and was discharged from the hospital. It was suggested that serial transthoracic echocardiography is useful for assessing the rapidly changeable pathophysiology in patients with acute pulmonary embolism.