Analysis of anticoagulant therapy by unfractionated heparin during pregnancy after mechanical valve replacement

Consensus has not been reached about the anticoagulant therapy to be used during pregnancy after mechanical valve replacement. Warfarin is a fetal toxicant, so we retrospectively examined anticoagulant therapy using unfractionated heparin.

Pregnancy after mechanical valve replacement occurred in 25 cases between 1983 and 2011. Targeted therapy using unfractionated heparin was administered in 9 pregnancies, which were divided into 3 groups: Group I received subcutaneous administration of heparin and APTT was measured twice weekly; Group II received heparin by constant rate infusion (CRI) and APTT was measured twice weekly; Group III received CRI of heparin and APTT was measured daily. Maternal complications consisted of valve thrombosis and perinatal bleeding in 1 pregnancy (Group I), intracranial hemorrhage in 2 pregnancies (Group II), and valve thrombosis and perinatal bleeding in 1 pregnancy (Group III). Two infants died in the neonatal period.

Each group showed a high rate of maternal complications, so a review of current anticoagulant treatment strategies is necessary.