肺血栓塞栓症再発を認めたpopliteal venous aneurysmの１例

Popliteal Venous Aneurysm with Recurrent Pulmonary Thromboembolism：a case report

要旨

　患者は72歳，男性．背部痛と労作時呼吸困難のため来院，心電図異常を伴った．身体所見や心エコーには明らかな異常はなかった．鑑別診断のため緊急心臓カテーテル検査を施行した．冠動脈に有意狭窄なく，左室壁運動は正常であった．高い肺動脈圧，肺動脈造影から肺血栓塞栓症と診断し，静脈造影により左下肢に血栓を内包した嚢状のpopliteal venous aneurysmが同定された．下大静脈に一時的なフィルターを挿入し，tPA静注による血栓溶解療法と抗凝固療法を行った．以後，希望によりワーファリンによる内科治療継続となった．しかし，7カ月後抗凝固療法下で肺血栓塞栓症が再発した．Popliteal venous aneurysmは稀な血管異常であるが，潜在的な塞栓源として繰り返し肺血栓塞栓症を引き起こすので注意しておかなければならない．

Summary

　A 72-year-old male was admitted to our hospital because of back pain and dyspnea on effort, with abnormal electrocardiographic data. Physical examination and cardiac ultrasonography were unremarkable. Emergency cardiac catheterization was performed. This revealed no significant coronay artery stenosis and normal left ventricular motion. However, high pulmonary arterial pressure was noticed and pulmonary arteriography demonstrated pulmonary thromboembolism(PTE). Venography of the lower limbs searching for the source of the emboli detected a sacciform left popliteal venous aneurysm, which included a thrombus in it. A temporary inferior vena caval filter was inserted and the patient was moved to the cardiology intensive care unit and treated with thrombolytic therapy by administering an intravenous drip injection of tissue plasminogen activator(tPA) followed by a anticoagulation drug. He refused to undergo surgical treatment for the venous aneurysm and continued the medical treatment with warfarin in the outpatient clinic. However, recurrent PTE occurred seven months later in spite of the administration of proper oral anticoagulation therapy. Popliteal venous aneurysm is a rare vascular anomality but can cause repetitive PTE, so it must be taken into consideration as a potential source of recurrent embolism.