Ross手術後遠隔期に右室-肺動脈導管に感染性心内膜炎をきたした1例

Infective Endocarditis in Right Ventricle （RV）-Pulmonary Artery （PA） Conduit Late after the Ross Procedure；Report of a Case

はじめに　Ross手術は1962年にRossらによって報告され，抗凝固療法が不要なこと，抗感染性，将来的成長の可能性などの利点を有する術式であり，現在までに数多くの良好な中期・長期成績が報告されている1）．Ross手術後の感染性心内膜炎（IE）の発症率は非常に低く，加えて診断が困難である2）．われわれはRoss手術後に慢性的な右室-肺動脈導管機能不全をきたし，歯科治療を契機にHaemophilus parainfluenzae（H. parainfluenzae）によるIEを発症した症例を経験した．

Ross procedure has been found to have a lower incidence of infective endocarditis compared to other aortic replacement procedure using prosthetic valves. We report a case of 25-year-old man who underwent Ross procedure for congenital aortic stenosis and regurgitation when he was 7 years old. He presented with fever and was highly suspected of infective endocarditis. All sets of blood cultures were positive for Heamophilus parainfluenzae. Autologous pericardial pulmonary valve was severely stenotic and computed tomography （CT） scan and radio isotope （RI） scan revealed infection at the stenotic valve. We performed right ventricle （RV）-pulmonary artery （PA） conduit replacement and he was discharged after completion of intravenous antibiotic treatment. We experienced a rare case of infective endocarditis in a patient late after Ross procedure. Prophylaxis against infective endocarditis is mandatory even in patients with infection resistant Ross procedure.