心内合併奇形を伴わない修正大血管転位症の1成人例と本邦における本症成人報告例の検討

A case report of corrected transposition of the great arteries without any associated defects in a 36-year-old man and the review of adult cases reported in Japan

　心内合併奇形，三尖弁閉鎖不全（TR）を認めない修正大血管転位症（CTGA）の36歳男性例を経験したので報告し，本邦での15歳以上の心内合併奇形のない報告例をまとめ，本症の診断に役立つ臨床的特徴，経過中に発現する合併症についても検討した。本例の心電図所見では，左軸偏位，1度房室ブロック，II，III，aV_F，V₁にてQ波をみ，septal qは欠如していた。断層心エコー，心臓カテーテル検査にて，心内合併奇形を伴わないSLL型のCTGAと診断した。本邦では15歳以上の心内奇形を認めないcTGAは本例を含め36例あるが，TRを合併しない例は本例が7例目であった。36例中TRは71％に，完全房室ブロックは20％に，心不全は45％に認めた。上記の後発する合併症の出現頻度は高く予後を左右する。症状のない場合CTGAは見逃されやすい。そこで心電図，断層心エコー図よりCTGAを注意深く診断すれば発見率が高まり，経過をよくfollow upすれば適切な処置が可能となろう。

We report a case in a 36-year-old man of corrected transposion of the great arteries (CTGA) without any associated defects. We also review clinical characteristics and later complications of adult CTGA cases reported in Japan. The patient was referred to our hospital for further examination of the abnormal ECG found during regular medical check-up. His ECG showed left axis deviation, first degree AV block, abnormal Q waves in the left precordial leads, and disappearance of septal q waves in the left precordial leads. His exercise capacity was found to be more than 12 METS by treadmill exercise testing. His roentgenogram re-vealed an egg-shaped ventricle with normal CTR (45%). The following findings were obtained by two-dimensional echocardiogram and heart catheteri-zation : 1) the functional left ventricle had the characteristics of the anatomical right ventricle, 2) The positions of the left and right atrioventricular valves were reversed, 3) Other cardiac anomalies such as VSD, pulmonary stenosis, tricuspid regurgi-tation (TR) were not proved. Therefore, he was diagnosed as having CTGA without any cardiac defects (SLL type). At present, with ages more than 15 years, 36 cases of CTGA without cardiac anomalies have been reported in Japan including this case. But most cases had significant TR. This case was the 7th reported case without the ac-companiment of TR. Among 36 cases, TR was found in 71%, complete AV block in 20%, and con-gestive heart failure was noted in 45%. Prognosis of CTGA without any defects is dependent on the appearance of TR, advanced AV block, and con-gestive heart failure. As these later fatal complica-tions are observed very often, it is important to detect the patient of CTGA accurately. In order to suspect and diagnose CTGA, ECG and two-dimensional echocardiography were found to be very useful.