肺血栓塞栓症を合併した若年者急性心筋梗塞の1例

A Case with Acute Myocardial Infarction Complicated Pulmonary Thromboembolism

　症例は37歳，男性．呼吸困難と前胸部痛を主訴に入院．心電図上心筋梗塞と診断し，連日抗凝固療法を含め加療した．第5病日，冠動脈造影を施行し，左前下行枝（LAD：＃6）に壁の不整と血栓浮遊像を認めた．第9病日の血液ガス分析にて低酸素血症を認め，第11病日に右前胸部の違和感と呼吸困難を訴えたため，肺血栓塞栓症の合併を疑い，肺血流シンチグラフィおよび肺動脈造影を施行した．肺血流シンチグラフィでは右上葉と下葉に欠損を認め，肺動脈造影にても右上葉の起始部と下葉枝の一部に血栓像を認めた．肺血栓塞栓症の診断の下に直ちに血栓溶解療法を開始し，6日後の肺血流シンチグラフィと肺動脈造影で改善が認められた．この症例は心筋梗塞発症後，抗凝固療法を行っていたにも関わらず，肺血栓塞栓症を合併したが，心筋梗塞・肺血栓塞栓症の原因として喫煙歴に加え，抗リン脂質抗体の陽性所見の関与が強く示唆された．

A 37-year-old male was admitted to hospital with dyspnea and chest pain. A diagnosis of acute myocardial infarction was made. Anticoagulant therapy was carried out. On the fifth day of hospitalization, coronary angio-graphy showed wall irregularity of the left anterior descending (# 6) and floating emboli. On the ninth day, blood gas analysis showed hypoxemia. On the 11th day, the patient complained of right precordial oppression and dyspnea. This condition suggested pulmonary thromboembolism. ^99mTc-MAA pulmonary perfusion scintigraphy showed defects in the right upper lobe and the right lower lobe. Pulmonary angiography showed total obstruction of the right upper pulmonary artery and partial obstruction of the right lower artery. Thrombolisis therapy was started immediately. Six days later, pulmonary perfusion scintigraphy and pulmo-nary angiography showed that reperfusion had taken place. Though this case was treated with anticoagulant therapy after the myocardial infarction episode, the patient had suffered from pulmonary thromboembolism. These findings suggested that a cause of pulmonary thromboembolism related-immobilization could have been smoking, and antiphospholipid antibody.