title: Anticoagulation during pregnancy in patients with a prosthetic heart valve.
abstract: Effective anticoagulation is mandatory for pregnant women with mechanical heart valves. Oral anticoagulants offer the best maternal protection against thrombosis, but their use might be associated with an appreciable risk of fetal malformations and pregnancy loss. By contrast, heparin derivatives are associated with a reduced risk of fetal damage, but an increased risk of valve thrombosis in the mother, even with appropriate dose adjustment and monitoring of therapeutic efficacy. Given the varying risks of available anticoagulation strategies, and the paucity of data to inform the optimal approach, no single accepted treatment option exists for pregnant women with mechanical prosthetic valves. Although low-molecular-weight heparin is considered more efficacious than unfractionated heparin, treatment failures, even at therapeutic levels of factor Xa inhibition, have been reported. The risk of warfarin-related embryopathy might be overstated, particularly at doses ≤ 5 mg daily. We advocate an individualized anticoagulation strategy that takes into account the patient's preferences, calls for the use of vitamin K antagonists throughout pregnancy (substituted with a heparin derivative only close to term) for those patients at the greatest risk of thromboembolism, and relies on close multidisciplinary collaboration between the cardiac and obstetric care teams.
authors.affiliation: Zena and Michael A. Wiener Cardiovascular Institute, Mount Sinai School of Medicine, One Gustave L. Levy Place, P O Box 1030, New York, NY 10029-6574, USA. jmcastellano.cardio@gmail.com
authors.forename: Jose M
authors.initials: JM
authors.lastname: Castellano
authors.forename: Rajeev L
authors.initials: RL
authors.lastname: Narayan
authors.forename: Prashant
authors.initials: P
authors.lastname: Vaishnava
authors.forename: Valentin
authors.initials: V
authors.lastname: Fuster
mesh_terms: D000284:Administration, Oral; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001777:Blood Coagulation / Q000187:drug effects*; D005260:Female; D005333:Fetus / Q000187:drug effects; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000295:instrumentation; D006801:Humans; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D011474:Prosthesis Design; D018570:Risk Assessment; D012307:Risk Factors; D013923:Thromboembolism / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants