【コラム】劇症型心筋炎の管理—炎症極期における血行動態の破綻を的確に補助し，自然治癒を待つ

Treatmen for fulminant myocarditis

血行動態の破綻を急激にきたし，致死的経過をとる急性心筋炎は，劇症型心筋炎と呼ばれる。多くは急性ウイルス感染によると考えられ，発熱を伴う感冒様の前駆症状がある。心不全もしくは不整脈による心症状を伴い，多くは心電図異常および心筋トロポニン上昇が診断のきっかけとなる。心筋生検により確定診断に至るが，最近では心臓MRIの重要性が増している。劇症化を事前に予見する手法は確立されておらず，マメに臨床経過を追うしかない。一般的に心筋炎に対する確実な根本治療は存在せず，炎症極期における血行動態の破綻を的確に補助し，自然治癒を待つのが基本戦略である。

Fulminant myocarditis is defined as acute myocarditis, with partial hemodynamic collapse, leading to a fatal outcome. Most cases are believed to be derived from acute viral infections and have preceding flu-like symptoms with fever. The patients, who manifest cardiac signs due to heart failure or arrhythmias, are initially suspected to have this condition based on abnormal electrocardiography and elevated serum myocardial troponin levels. The definitive diagnosis is made by histopathological evaluation of an endomyocardial biopsy, but cardiac magnetic resonance has recently become increasingly important because of its non-invasiveness. A method for predicting fulminant illness has not been established, and there is no choice but to follow the clinical course closely. There is no reliable causal treatment for myocarditis in general, so the principal management strategy is to accurately support the hemodynamic condition including hemodynamic collapse until spontaneous recovery from inflammation.