ANTICOAGULATION STRATEGIES IN PATIENTS UNDERGOING MECHANICAL VALVE REPLACEMENT SURGERY IN FERTILE AGE: THROMBOTIC AND HEMORRHAGIC RISKS AND PREGNANCY PLANNING

Abstract

Introduction: Young patients requiring heart valve replacement often receive mechanical prostheses due to their superior durability compared to biological prostheses, avoiding the need for multiple reoperations in a relatively short period of time. However, the presence of a mechanical prosthesis requires lifelong oral anticoagulation to prevent catastrophic thromboembolic events. This need for chronic anticoagulation presents unique challenges for women of childbearing age, particularly when considering pregnancy. The hypercoagulable state of pregnancy, coupled with the inherent risks of anticoagulants on the fetus and mother, makes the clinical management and pregnancy planning of this population highly complex. Objective: The objective of this systematic literature review was to analyze the anticoagulation strategies employed in female patients of childbearing age with mechanical valve prostheses, assessing maternal and fetal thrombotic and hemorrhagic risks, and the influence of pregnancy planning on outcomes. Methodology: A systematic literature review was conducted based on the principles of the PRISMA checklist. The search was performed in the electronic databases PubMed, SciELO and Web of Science, using the descriptors: "Mechanical Heart Valve", "Anticoagulation", "Pregnancy", "Women" and "Outcomes". Articles published in the last 10 years were included. Inclusion criteria consisted of studies involving women of childbearing age with mechanical valve prostheses who became pregnant or planned pregnancy, evaluating different anticoagulant regimens and reporting maternal or fetal outcomes (thrombotic, hemorrhagic or related to development). Studies with male patients or that exclusively addressed biological prostheses were excluded. Results: The studies analyzed demonstrated that the management of anticoagulation in pregnant women with mechanical prostheses represented a challenge with significant risks. Warfarin, although effective in preventing maternal valve thrombosis, was associated with a high risk of first-trimester embryopathy and fetal hemorrhage. Heparins (unfractionated or low molecular weight) were options with lower teratogenic risk, but with a potential increased risk of maternal valve thrombosis, especially if control was not ideal, and hemorrhagic complications. Individualized strategies, often combining different anticoagulants at different stages of pregnancy, were employed in an attempt to minimize risks. Prior gestational planning and rigorous monitoring in specialized centers were crucial to optimize outcomes, but the risks to mother and fetus remained high. Conclusion: Pregnancy in women with mechanical valve prostheses constituted a high-risk condition due to the need for anticoagulation. The choice and management of anticoagulant therapy during pregnancy required a delicate balance between preventing valve thrombosis and minimizing fetal risks. Gestational planning and multidisciplinary monitoring were essential to mitigate, but not eliminate, the inherent risks, highlighting the complexity and seriousness of this clinical situation.