びまん性汎細気管支炎の増悪を契機に発症したたこつぼ心筋障害の1例

A Case of Diffuse Panbronchiolitis Complicated with Takotsubo Cardiomyopathy

要旨　症例は54歳女性．20××年9月，呼吸困難，意識障害にて当科へ緊急入院となった．入院時は呼吸性アシドーシスを伴う著明な低酸素血症を呈していた．胸部X線写真では肺水腫像を呈しており，心電図でⅠ，aV_LでST上昇を認めた．冠動脈造影は正常であったが，左室造影で心基部の収縮は正常であるものの左室心尖部を中心とした広汎な壁運動低下を認め，たこつぼ心筋障害と診断した．集中治療室管理を行い，第17病日には左室壁運動の改善を認めたが，低酸素血症は残存した．胸部CTではびまん性粒状影を認め，閉塞性換気障害，慢性副鼻腔炎の存在などからびまん性汎細気管支炎と診断した．エリスロマイシン少量療法を行い，低酸素血症と1秒量の改善を得た．本症例は，びまん性汎細気管支炎の増悪を契機にたこつぼ心筋障害を発症したと考えられた．

　A 54 year-old woman was admitted with dyspnea and loss of consciousness. In addition, she had severe hypercapnic respiratory failure. A chest radiograph on admission indicated the presence of butterfly shadows and cardiomegaly. An electrocardiography(ECG)performed on the day of admission showed ST elevation in leads Ⅰ and aV_L, whereas an ECG performed on the 4^th hospital day showed negative T waves and QT interval prolongation in leads V2 to V6. Coronary arteries appeared normal on coronary angiography. However, left ventriculography showed an asynergy of apical akinesis and basal hyperkinesis. Thus, we diagnosed the condition as takotsubo cardiomyopathy with congestive heart failure. The patient was treated in the intensive care unit, and although the heart failure improved, she continued to exhibit moderate hypoxemia. Chest computed tomography scans showed diffuse centrilobular small nodular shadows in both lung fields. In addition, a pulmonary function test showed marked obstructive impairment. We diagnosed this condition as diffuse panbronchiolitis(DPB)based on physical examination findings, a positive cold agglutinin reaction, and radiological findings as well as the presence of sinusitis and obstructive pulmonary impairment. Long-term chemotherapy with erythromycin was administered leading to an improvement of hypoxia. Thus, we report a rare case of takotsubo cardiomyopathy occurring in the acute exacerbation period of DPB.