Society for Maternal-Fetal Medicine Consult Series #61: Anticoagulation in pregnant patients with cardiac disease

Special considerations in assisted reproductive technology for patients with cardiovascular disease

Many individuals with cardiovascular disease can benefit from the availability of assisted reproductive technologies (ARTs) for family building. Its use for this population may be because of underlying infertility, a need for fertility preservation before disease worsening or heart transplant, a genetic cardiac condition they believe to avoid passing to offspring, or the need to use a gestational surrogate in the setting of cardiovascular contraindications to pregnancy. Cardiovascular disease exists on a spectrum, from mild and common diseases that pose minimal threat to maternal health during pregnancy to severe and rare diseases with a high risk of morbidity and maternal mortality if ART or pregnancy is pursued. In this review, we characterize the varying cardiovascular diseases from the lens of the reproductive-aged patient undergoing ART. We classify the necessary steps in the pre-ART evaluation from the multidisciplinary team, discuss risk stratification before ART treatment and possible subsequent pregnancy, and offer specific evidence-based guidance on the care of these patients during the in vitro fertilization and embryo transfer cycles.

Inpatient pharmacological thromboprophylaxis in the antepartum period: an argument for risk-based thromboprophylaxis

Venous thromboembolism (VTE) is a significant cause of maternal morbidity and mortality in the United States. People hospitalized during pregnancy for reasons other than routine birth (ie, during antepartum admissions) are at increased risk of VTE compared with nonhospitalized obstetric patients, but there is no consensus regarding which patients should receive thromboprophylaxis during antepartum hospitalizations as the absolute event rates are low and anticoagulation can complicate antepartum management. We argue that an approach informed by individualized patient risk assessment is likely to produce the greatest net benefit for patients. Such an approach would avoid the pitfalls of universal pharmacologic prophylaxis (potential to interfere with unplanned delivery or receipt of neuraxial anesthesia) among patients for whom the absolute risk of VTE is low. In contrast, approaches that withhold pharmacologic prophylaxis from all antepartum patients likely place some at significant risk of VTE. We outline the arguments against universal pharmacologic thromboprophylaxis and against universal avoidance of pharmacologic thromboprophylaxis and discuss a risk-based approach proposed at our institution. Finally, we outline a research agenda for identification of optimal antepartum anticoagulation strategies.

Comparison of Two Methods of Antepartum Anticoagulation: Continuation of Enoxaparin until Scheduled Induction of Labor Versus Transitioning to Heparin with Spontaneous Labor

Pregnancy is a hypercoagulable state. There is a lack of strong evidence-based guidance regarding management when anticoagulation is required to prevent or treat venous thromboembolism during pregnancy. In practice, some patients are prescribed enoxaparin and transitioned to heparin due to the shorter half-life in the setting of an unpredictable delivery despite less predictable pharmacokinetics of heparin compared with enoxaparin, while others are continued on enoxaparin with a scheduled delivery. This work retrospectively evaluates obstetrical and neonatal outcomes between these two practices for 194 live singleton deliveries from 179 patients in a single institution January 2017 through May 2022. A Bayesian regression was used to control for confounders including dosing regimens. This work found no statistically significant differences in blood loss at time of delivery or availability of neuraxial anesthesia. This suggests continuing enoxaparin is noninferior to transitioning to heparin when anticoagulation is indicated in pregnancy.

A Complex Adult Congenital Heart Disease Case in Pregnancy: A Multidisciplinary Approach

Multidisciplinary teams decrease the likelihood of adverse pregnancy outcomes in high-risk pregnant cardiac patients. We present the case of a patient with complex congenital heart disease and a mechanical mitral valve, whose treatment included warfarin until delivery despite the discovery of placental hematomas. A multidisciplinary approach mitigated both maternal and fetal adverse pregnancy outcomes.

Care and Monitoring of Pregnant Patients With Left Ventricular Assist Devices

Cardiovascular disease is one of the leading causes of maternal mortality in the United States. Although still rare, pregnancy in patients with left ventricular assist devices (LVADs) is becoming more common. Typical indications for the use of LVADs in reproductive-aged females include ischemic cardiomyopathy, nonischemic (familial) dilated cardiomyopathy, peripartum cardiomyopathy, and some forms of myocarditis. An LVAD drains blood through a cannula placed into the apex of the left ventricle and then returns it to the proximal aorta bypassing the aortic valve allowing hemodynamic support in parallel with the native circulation. The physiologic changes associated with pregnancy, mainly increased blood volume and hypercoagulability, may adversely affect patients with LVADs, leading to many experts recommending against pregnancy. Maternal-fetal medicine specialists should have a central role within a multidisciplinary team required to provide optimal care for this high-risk group of patients.

A Case Series of Parturients With Mechanical Mitral Valves: Anticoagulation Management During Labor and Delivery

More women with mechanical mitral valves (MMVs) are pursuing pregnancy. Guidelines exist for pregnancy anticoagulation, but they do not address individualized anticoagulation during delivery-a period of risk for bleeding, thrombosis, and anesthetic complications. This case series of parturients with MMVs highlights the challenges in, and the evidence and strategies for, treating these patients. (Level of Difficulty: Advanced.).

Treatment of Arrhythmias During Pregnancy

Cardiac disease is the most common cause of maternal mortality in developed nations. Cardiac arrhythmias are frequent among patients with structural heart disease and may require immediate treatment to prevent hemodynamic instability leading to acute maternal and fetal decompensation. Antiarrhythmic therapy during pregnancy should follow the same principles recommended for nonpregnant individuals. Although multidisciplinary management is recommended, obstetricians, and maternal-fetal medicine specialists may sometimes need to emergently recognize and treat rhythm anomalies before support services become available.