成人期に到達した修正大血管転位症

Congenitally Corrected Transposition of the Great Arteries （TGA） in Adult

修正大血管転位症は，心房心室不一致，心室大血管不一致を認める先天性心臓病であり，循環は生理学的に修正されるが，多くの場合心室中隔欠損症などの心内病変を伴い，体循環は解剖学的右室が担う．修正大血管転位症の外科治療においては，解剖学的修復術，機能的修復術，単心室治療などが用いられている．しかしながら機能的修復術は，解剖学的右室を体心室として使用するため，遠隔期において解剖学的右室不全，三尖弁閉鎖不全症，不整脈などの問題が多くみられる1，2）．われわれは，成人期に到達した体心室が解剖学的右室である修正大血管転位症例について検討した．

Objectives：In patients with congenitally corrected transposition of the great arteries （cc-TGA）， the morphological right ventricle （RV） sustains the systemic circulation and is frequently associated with progressive tricuspid regurgitation and declining RV function.

Methods：Thirty-four patients with cc-TGA and systemic RV were enrolled in this retrospective study to examine long-term outcome.

Results：Age was averaged 38.5 years. Associated cardiac anomaly included ventricular septal defect （VSD） and pulmonary stenosis in 18, VSD in 4. Twelve had no associated cardiac defect. The physiologic repair was performed in 22 patients at the mean age of 7.8 years old. Reoperation was frequent including tricuspid valve surgery in 11 and left ventricle （LV）-pulmonary artery （PA） conduit replacement in 10. Five patients needed pacemaker implantation due to heart block. Aortic insufficiency was a relatively common finding and aortic valve replacement was performed in 4. All but 2 patients were better than New York Heart Association （NYHA） class Ⅱ. One needed implantable ventricular assist device implantation and the other underwent heart transplantation.

Conclusions：Long-term outcome for patients with cc-TGA was satisfactory. Frequent reoperations including tricuspid valve surgery and LV-PA conduit replacement were required. Further careful follow-up will be needed to detect the progression of RV dysfunction and tricuspid and aortic insufficiency.