拡張型心筋症様病型へ移行後8年以上生存しえた肥大型心筋症の1例

A Case of a Patient with Hypertrophic Cardiomyopathy who Survived more than 8 Years after Progression to the Dilated Phase

　症例は62歳，女性．43歳時，心電図異常を指摘され，51歳時，肥大型非閉塞性心筋症と診断された．54歳時にうっ血性心不全を呈したが，利尿剤投与で改善した．55歳時，精査の結果，拡張型心筋症様病型への移行型と診断された．以後，少量の利尿剤投与のみで8年間にわたって症状に乏しいまま緩徐に心機能低下を来し，不整脈の発生から短期間で死に至った．剖検では，心筋のびまん性，全周性，斑状の線維化および微小血管の壁肥厚像と，微小血管内小血栓，心筋の小梗塞巣を散見した．本邦における報告例の検討では，肥大型心筋症から拡張型心筋症様病型への移行例には若年例と成人例で臨床経過および死因に違いが認められた．本症例は，本疾患の1つのパターンと推測されたが，長期にわたる臨床経過および病理所見がともに興味深い症例と思われた．

A patient with hypertrophic cardiomyopathy (HCM) had an episode of congestive heart failure when she was 54 years old, but recovered easily using diuretics. Since then she had been free from heart failure due to the administration of a minimum dose of diuretics. Her NYHA class was 2. However, her cardiac function became worse progressively and atrial tachyarrhyth-mias occurred frequently. Echocardiography revealed that her left ventricle had dilated and was in a diffuse hypokinetic state. She died of ventricular arrhythmias 8 years after progression to the dilated phase of HCM.