Becker型および肢体型筋ジストロフィーの心機能の長期追跡

Long-term follow up Study of Cardiac Involvement in Becker and Limb-girdle Muscular Dystrophies

要旨

　Becker型筋ジストロフィー(BMD)と肢体型筋ジストロフィー(LGMD)の心機能を一施設で長期間追跡した報告は少ない．今回，長期入院中のBMD8名，LGMD8名を対象に心電図，心エコー，血清学的検査を行い，その心病変を4～8年間追跡した．観察期間中に拡張型心筋症様に変化したものがBMD4例，LGMD2例，心エコー上駆出分画の低下したものがBMD6例，LGMD5例あり心筋病変の多くは進行性であった．心筋病変の進行した症例のうち，心電図に著変の認められなかったものは，BMDで2例，LGMDで1例であった．そして，クレアチンキナーゼ(CK)，CKアイソザイム心筋分画，ヒト心房性および脳性ナトリウム利尿ペプチドは一定の傾向を示さず，心エコー上の心筋病変の進行を反映しなかった．以上より，BMDとLGMDでは定期的なルチーンの循環器検査は，心病変の把握に重要であると思われた．

MostpatientswithBeckermuscular(BMD) andLimb-girdle(LGMD) muscular dystrophies are known to die of cardiac involvement, but long-term follow-up study of this pathology is somewhat lacking. Hence, we retrospectively analyzed routine cardiovascular tests in patients with BMD and LGMD, who had been hospitalized in chronic condition in the Suzuka National Hospital. We examined, each of the eight patients with BMD and LGMD,using electrocardiograph(ECG), echocardiograph and data concerning serum concentrations of creatine kinase(CK) with its myocardial isozyme(CK-MB), human atrial(hANP) and brain(BNP) natriuretic peptide, respectively. We found echocardiographically, that myocardial involvement similar to dilated cardiomyopathy was progressive in four patients with BMD and in two with LGMD during the follow-up for 4-8 years. However, this myocardial damage able to be detected by the echocardiogram was reflected in neither the ECG nor in the serum CK, CK-MB, hANP and BNP. Our results suggest that the progression in myocardial involvement, conduction disturbances and skeletal muscle weakness were able to occur separately in BMD and LGMD. Hence, the routine follow-up of cardiac function in these dystrophies seems mandatory to assess the risk of cardiac involvement.