Optimizing Pregnancy Plans & Management in Congenital Heart Disease Patients

Featuring three experts from the University of Washington, the “Reproductive Implications of Congenital Heart Disease” session at the 2021 ACOG Annual Clinical and Scientific Meeting explored the proper counseling and management strategies needed to help adult patients with congenital heart disease (CHD) have successful pregnancies.

Here’s a recap of what was discussed.

The Growing Prevalence of Pregnancy in CHD Patients

Kicking off the session was Dr. Yonatan Buber, Associate Professor of Medicine and attending cardiologist at the University of Washington. He began by sharing the below statistics demonstrating how the number of adult patients with CHD has increased in the US over the past 30 years:

• 1990: 750,000 adults
• 2000: 1 million adults
• 2010: 1.25 million adults
• Recent estimates: 1.6 million adults

Coinciding with this increased survival rate is an increase in women with CHD who wish to start families of their own. According to a 2008 study, there was a 35 percent increase in deliveries among women with CHD between 1998 and 2007.

Complicating this trend, however, is the fact that a study from 2019 found that up to 60 percent of pregnant women with CHD have defects of moderate complexity, 10 percent have defects of severe complexity, and more than 20 percent have comorbidities.

Given this data, Dr. Buber stressed the importance of specialized adult CHD programs that focus on providing timely and holistic education in addition to pre-pregnancy counseling, which includes discussions on maternal risk, delivery, postpartum care, and the risk of CHD transmission.

Preventing Unplanned Pregnancies in CHD Patients

Next up to discuss the importance of reducing the risk of unplanned pregnancies among CHD patients was Dr. Laura Sienas, Maternal-Fetal Medicine subspecialist in cardio-obstetrics at the University of Washington.

According to Dr. Sienas, many women with CHD have heard mixed or inconsistent messages regarding fertility, with one of the most common being that they can’t get pregnant. This inaccurate message has caused many women with CHD to not use contraceptive methods.

In fact, a recent study of sexually active CHD patients found that 25 percent of women weren’t using contraceptive methods, and 16 percent were using less effective methods, such as condoms or withdrawal. And since unplanned pregnancies can come with a high risk of poor maternal and fetal outcomes, it’s important for OB-GYNs to help with family planning.

On this note, Dr. Sienas referenced the CDC’s Medical Eligibility Criteria for Contraceptive Use, which states that women with heart disease with concurrent hypertension or risk of thrombosis should avoid estrogen-containing methods. The guidelines also state that both forms of IUD and all forms of emergency contraceptives are safe in CHD patients.

However, she did note that some cardiac conditions like severe right heart failure and pulmonary hypertension are incompatible with the physiological changes that occur in pregnancy; for these patients, a discussion on permanent contraception should take place.

For those patients who wish to start a family, Dr. Sienas stressed the importance of pre-pregnancy evaluations, which include the following components:

• History and physical exam with special review of cardiac surgeries
• Baseline review of symptoms, such as an inability to lie flat and exercise tolerance
• Baseline lab work
• An electrocardiogram
• Referral to a cardiologist for pre-pregnancy screening, which might include an echocardiogram and other similar tests
• Potential referral to a geneticist to assess the risk of inheritance to future children

And while it’s not an official component of pre-pregnancy evaluations, Dr. Sienas also urged clinicians to be prepared to answer patients’ questions on achieving and tolerating pregnancy, to which she offered the following guideposts:

• Women with CHD have higher rates of infertility, and the treatment of infertility is more complex since these treatments have a higher risk of hypertension and thrombosis.
• Miscarriage rates are also more common in women with CHD.
• When it comes to the impact of CHD on pregnancy, some of the risks include pre-term delivery, fetal growth restriction, and maternal risks, such as heart failure and prolonged hospitalization.
• In the general population, the risk of CHD in the fetus is 1 percent; the risk increases to 5 percent in women with CHD.

Despite these potentially alarming statistics, however, Dr. Sienas noted that successful pregnancies are possible with proper planning and management, which led to the next part of the session.

Pregnancy Management & Delivery Planning in CHD Patients

Closing out the session was Dr. Catherine M Albright, Assistant Professor in the Division of Maternal-Fetal Medicine at the University of Washington, who demonstrated how she approaches pregnancy planning and management through the story of one of her patients she referred to as “Ms. Z.”

At the time, Ms. Z was 8 weeks pregnant and attending her first prenatal visit. When discussing the physiology of pregnancy with her patients, Dr. Albright describes it as “nature’s stress test” in that there’s a significant increase in heart rate and blood volume, which might not be well-tolerated in patients with an underlying heart defect.

As one might imagine, Ms. Z then asked how they would know her risk, and Dr. Albright shared the two major scoring systems used to stratify a patient’s risk:

• MWHO: Short for the Modified World Health Organization Risk Classification, MWHO is primarily based on a patient’s underlying structural abnormality and stages patients from 1 to 4, with 4 being the most complex. MWHO provides a framework for the risk of cardiac events during pregnancy in addition to a recommended timing of cardiology follow-up and delivery.
• CARPREG II Score: This system aims to predict the risk of cardiac complications during pregnancy and includes cardiac diagnostics as well as factors related to process of care, such as timing of initial pregnancy assessment.

Another topic Dr. Albright discusses with patients like Ms. Z is symptoms. According to Dr. Albright, many symptoms of cardiac deterioration during pregnancy are not recognized as such, resulting in evaluation and treatment delays which, in turn, increase the risk of morbidity and death. Some of the symptoms Dr. Albright tells patients to look for include:

• Shortness of breath
• Palpitations
• Chest pain
• Fatigue

And while most of these are normal symptoms to have in pregnancy, Dr. Albright told Ms. Z to seek care immediately if the symptoms became significant or severe. Dr. Albright reviews these symptoms with patients at every visit and even looks ahead to the mode and timing of delivery. According to her, vaginal delivery at term is preferred for most patients with CHD, but some patients do require cesarean sections.

To conclude, Dr. Albright noted that most CHD patients can have normal and successful pregnancies, but it’s important for OB-GYNs to be aware that these patients do need some extra care and that cardio-obstetricians are here to partner with OB-GYNs to ensure the best outcomes for patients.