機械弁による大動脈弁置換術後低用量warfarin 管理下の妊娠・出産

Pregnant women undergoing mechanical valve replacement are at a considerable risk of thromboembolic events, bleeding, and fetotoxicity associated with the administration of vitamin K antagonists and some other anticoagulants. We present our clinical experience of pregnancy and childbirth in a young woman who underwent aortic valve replacement （AVR） with a mechanical valve. A young woman underwent AVR with a bioprosthetic valve for a diagnosis of aortic regurgitation and bicuspid aortic valve at age 23. Four years later, structural valve deterioration（SVD） of the prosthetic valve necessitated redo AVR with bioprosthesis. Three years after the redo AVR, she developed recurrent SVD of the bioprosthesis, and the 3rd AVR operation was performed using an On-X mechanical valve, which allows reduced anticoagulation. She conceived 5 months after AVR using the On-X valve. Anticoagulation therapy was administered with a low-dose vitamin K antagonist combined with heparin infusion during pregnancy. No anticoagulation-induced maternal and fetal complications occurred throughout the pregnancy. The On-X valve, which allows lower levels of anticoagulation is useful in women wishing to get pregnant.