Pulmonary Embolism Caused by Popliteal Vein Aneurysm: A Case Report.

In this case report, we describe an unusual episode of bilateral submassive pulmonary embolism (PE) caused by a popliteal vein aneurysm (PVA). The development of PE stems from many risk factors including obesity (BMI³ 30 kg/m2), hypertension, cigarette smoking (greater than 25 cigarettes per day), increasing age, surgery, immobility, malignancy, and inherited thrombophilia. A PVA is a rare but significant cause of PE. A 28-year-old male presented to the emergency department with progressive shortness of breath. He had no significant past medical history, no family history of deep vein thrombosis or PE, and no recent surgeries, travel, or trauma. A physical exam revealed he was saturating 96 percent on 2 L/minute oxygen through a nasal cannula and was noted to have a heart rate in the 90 beats per minute range that quickly increased to 150 beats per minute with minimal exertion. An initial laboratory workup was unrevealing except for an elevated D-dimer. A chest radiograph demonstrated no cardiopulmonary abnormalities. Computed tomography angiography of the chest was performed and revealed multiple bilateral pulmonary emboli. An urgent echocardiogram then revealed evidence of right heart strain with a dilated right ventricle. A subsequent bilateral venous duplex scan of the lower extremities was performed, which revealed a left PVA. Vascular surgery was performed, specifically emergent catheter-directed lysis with the placement of a temporary inferior vena cava (IVC) filter. The patient was started on rivaroxaban oral anticoagulation therapy and then discharged home without incident. Several months later, he underwent uncomplicated surgical repair of his left PVA. This case illustrates PVA as a rare but noteworthy cause of PE. Doctors should consider this diagnosis in patients with recurrent PE or when the cause of PE is unknown. Although the exact etiology is not known, inflammation, trauma, degenerative changes, and congenital weakness of venous wall have all been proposed as causes of venous aneurysms. The definitive management of a PVA is surgical repair. Some studies suggest recurrent PE in as high as 80 percent of patients on oral anticoagulation alone. Therefore, an IVC filter is often placed to prevent further thrombi progression until definitive surgical treatment of the aneurysm has been performed.