Prosthetic heart valves raise pregnancy risks: the complications may be preventable and suggest a need for specialized care and close monitoring.(Clinical Rounds)

DALLAS -- Pregnancy in women with a prosthetic heart valve was associated with a high risk of maternal and fetal complications, according to findings in a study in Brazil with 70 women and 86 pregnancies. But some complications may be preventable.

Maternal complications were primarily thromboembolic events and hemorrhages. Embryopathy was usually caused by oral anticoagulant use during the first trimester, whereas anticoagulant use during the second and third trimesters was associated with a high fetal loss rate.

"These complications may be preventable and suggest a need for specialized care and close monitoring of pregnancies in women with a prosthetic heart valve," said Dr. Citania L. Tedoldi and her associates in a poster at the annual scientific sessions of the American Heart Association.

The researchers reviewed the pregnancy outcomes of women with prosthetic heart valves who delivered at any of three tertiary centers in Brazil during January 1995-December 2004. The mean age of the mothers was 26 years.

In 69 pregnancies, the mothers received anticoagulant therapy in the first trimester. Of those, 47 received an oral anticoagulant and 22 were treated with heparin. Anti-coagulants were used on 65 women during the second trimester (61 on an oral agent and 4 on heparin), and 60 received an anticoagulant during the third trimester (57 on an oral agent and 3 on heparin).

During pregnancy or delivery, 2 women died, 9 had a major thromboembolism, and 15 developed a major bleed. The two deaths were both caused by thrombosis of prosthetic mitral valves triggered by inadequate anticoagulation with heparin. All of the ...