中部中隔閉塞を伴った心尖部肥大型心筋症に慢性血栓塞栓性肺高血圧症が合併した1例

Apical Hypertrophy with Midventricular Obstruction Complicated by Chronic Thromboembolic Pulmonary Hypertension

　患者は76歳，女性．中部中隔閉塞を伴う心尖部肥大型心筋症の治療中，労作時呼吸困難を主訴に入院．肺高血圧症（平均肺動脈圧55mmHg）を認めた．経過中，立位歩行後に心肺停止を起こした．意識は回復し後遺症は残さなかった．肺血栓塞栓症を疑いワーファリンを投与した．約1カ月後の造影CTでは中枢肺動脈に血栓は認めなかったが，肺血流シンチグラム上，多発性陰影欠損があり，本症を示唆した．抗凝固療法と在宅酸素療法を行い，約1年6カ月経過したが，肺血流シンチグラムの所見に変化はない．本症例は肺動脈造影で血栓を確認していないが，亜急性期のみならず慢性期の肺血流シンチグラムで多発性血流欠損を認め，肺高血圧症を伴うことから慢性血栓塞栓性肺高血圧症と診断した．本症は，基礎に心疾患を合併している場合，臨床症状がマスクされ診断が困難となる症例もある．なかでも中部中隔閉塞を伴う心尖部肥大型心筋症と慢性血栓塞栓性肺高血圧症の合併例は稀であり報告した．

　A 76-year-old woman who had apical hypertrophiccardiomyopathy with midventricular obstruction wasadmitted to hospital because of exertional dyspnea.Pulmonary hypertension was disclosed (mean pulmonary arterial pressure was 55mmHg). In follow-up days, after upright position and walk, cardiopulmonaryarrest occurred. She recovered consciousness and noneurological problem was found. We suspected pulmonary thromboembolism and started the admnistration ofwarfarin. One month later, enhanced CT scan showed nocentral pulmonary arterial thrombus, but pulmonaryperfusion scintigram revealed multiple defects whichsuggested pulmonary thromboembolism. Afteranticoagulation and home oxygen therapy for one yearand a half, pulmonary perfusion scintigram showed nochange during the interval. In this case, we could notperform a pulmonary artery angiogram, but the findingof multiple lung defects in the pulmonary perfusionscintigram in the subacute and chronic phase, accompanied by pulmonary hypertension, confirmed thediagnosis of chronic thromboembolic pulmonary hypertension. The clinical diagnostic rate of this disease islowest when cardiac disease is complicated. In somecases, diagnosis is difficult because cardiac diseasemasks manifestation. We reported a case of apicalhypertrophic cardiomyopahty with midventricularobstruction complicated by chronic thromboembolicpulmonary hypertension because such a clinical situation is rare.