佐藤 早見¹, 渡邉 百合¹, 吉武 靖展¹, 福島 敬子¹, 植田 和子¹, 尾田 敏恵¹, 柏木 稔², 眞柴 順子³, 大谷 規彰³, 林 靖生³

Hayami SATOU¹, Yuri WATANABE¹, Yasunobu YOSHITAKE¹, Keiko FUKUSHIMA¹, Kazuko UEDA¹, Toshie ODA¹, Minoru KASHIWAGI², Jyunko MASHIBA³, Kisho OHTANI³, Yasuo HAYASHI³

¹原三信病院生理検査室, ²原三信病院腎臓内科, ³原三信病院循環器科

¹Cardiac Ultrasound Laboratory, Harasanshin General Hospital, ²Department of Nephrology, Harasanshin General Hospital, ³Department of Cardiology, Harasanshin General Hospital

キーワード : echocardiography, intertrabecular recesses, isolated noncompaction of the ventricular myocardium, magnetic resonance imaging

左室心筋緻密化障害は，心腔内に著明に突出した肉柱と，肉柱間の深い陥凹を特徴とする，稀な先天性心疾患である．症状は，無症状から心不全や不整脈，塞栓症など多岐にわたるが，症状出現により診断されることが多い．我々は無症候性の左室心筋緻密化障害で，4年間経過観察した症例を報告する．症例は31歳女性で，肉眼的血尿の精査のために腎生検目的で入院となった．術前の心エコー図では，左心室下壁の菲薄化と壁運動低下，さらには下後壁に不規則に突出する肉柱構造とカラードプラ法で肉柱間隙内に入り込む血流像を認めた．また，MRI検査では心エコー図と同様に，下壁から心尖部にかけての肉柱構造とそれに伴う深い間隙が観察された．よって，心筋緻密化障害と考えられた．その後4年間の経過観察を行っているが，無症状であり，不整脈や塞栓症などの合併症は認められていない．左室心筋緻密化障害は，小児科領域での稀な心筋疾患とされてきたが，成人でも比較的多いと報告されるようになった．診断には心エコーとMRIが有用と考えられる．その予後は必ずしも楽観出来るものではないため，早期診断が重要である．

Noncompaction of the left ventricular myocardium is a rare congenital disorder characterized by the presence of numerous prominent trabeculations and intertrabecular recesses in the left ventricle. Clinical manifestations vary from no symptoms to congestive heart failure, arrhythmias, and thromboemboli. We report a case in which asymptomatic noncompaction of the left ventricular myocardium was considered likely. The patient was a previously healthy 31-year-old woman who presented with gross hematuria and was admitted to our hospital for renal biopsy. Perioperative echocardiograms demonstrated thinning and hypokinesis in the left ventricular inferior wall. Spongiform trabeculations were found in the inferior and posterior wall, and color flow Doppler studies confirmed the presence of blood flow within them. Cine magnetic resonance imaging showed prominent trabeculations and deep intertrabecular recesses. These findings were consistent with isolated noncompaction of the left ventricular myocardium. The patient has been asymptomatic and presented no major complications during 4 years of follow-up. Isolated noncompaction of the left ventricular myocardium is a cardiomyopathy that is more prevalent than previously reported. Combined echocardiographic and magnetic resonance imaging findings are important in the diagnosis of this entity. Because of the relatively high incidence of congestive heart failure, arrhythmias, and thromboemboli, their early diagnosis is important.