Los Angeles: Women who are born with high-risk heart defects can have successful pregnancies if they get the right medical support, according to new U.S. guidelines.
The guidelines are the first from the American Heart Association to offer a road map to women with congenital heart defects who have long been told to avoid pregnancy altogether, said Mary Canobbio, a researcher at the University of California, Los Angeles and chair of the committee that drafted the advice.
“Historically the tendency has been to advise these women to avoid pregnancy because the defect and surgeries done to keep these women alive are complex and the long term survival is difficult to predict – so concern has been that the ‘added burden’ of pregnancy could potentially cause more problems and decrease their own long term survival,” Canobbio said by email.
Congenital heart defects such as defective vessels, leaky valves or holes in the heart muscle are among the most common types of birth defects. These structural problems can cause symptoms like abnormal heart rhythm and breathing difficulties and may require surgery or a heart transplant.
While most girls born today with congenital heart disease will reach childbearing age, pregnancy carries a risk of complications for both these mothers and their babies.
One concern is that women’s blood volume increases by 50 percent during pregnancy to help support her growing baby. That means the mother’s heart must be able to handle the additional burden, Canobbio said.
Hormonal changes during pregnancy can also increase the risk of irregular heart rhythm and blood clotting. In healthy women these changes aren’t usually a problem, but in women with structural heart damage this can increase their risk of stroke, Canobbio added.
Pre-pregnancy counseling is essential for women with complex congenital heart defects so that they have a clear understanding of how their heart abnormalities could affect both their own health and the health of their child during a pregnancy, the new guidelines advise.
For some structural heart problems, and women with a family history of these problems dating back several generations, genetic screening before conception can help estimate the odds that women may pass heart defects on to their children. Once pregnant, a delivery plan is also essential, so the medical team can anticipate problems that could happen during and following delivery and be prepared.
Ideally, women should deliver their babies at medical centers that have a cardiologist experienced in managing complex congenital heart disease, obstetricians trained in high-risk maternal-fetal medicine, cardiac anesthesia and a cardiac surgical team.
After delivery, women need monitoring for up to six months because the effects of pregnancy can linger that long, the guidelines also note.
The scientific statement, published in Circulation, will likely set a new standard of prenatal, delivery and postpartum care for women with congenital heart defects because this marks the first time a leading U.S. cardiology group has weighed in, said Dr. Wayne Franklin, medical director of the adult congenital heart disease program at Texas Children’s Hospital in Houston.
“The take-home message here is that women should talk to their cardiologist, and also obtain preconception counseling with a maternal-fetal-medicine specialist, if they have a heart problem but are considering pregnancy,” Franklin, a researcher in obstetrics and cardiology who wasn’t involved in the guidelines, said by email.
That’s because normal changes in blood volume, heart rate and blood pressure that happen in every pregnancy can adversely affect women with congenital heart disease, Franklin said.
And, mothers with congenital heart disease have an 8- to 10-fold increase in the chance of their baby having a congenital heart defect, Franklin added. With close monitoring, many problems in developing infants can be detected before infants are born.
“We now know that with close collaboration with a multi-disciplinary team, we can achieve excellent outcomes for both the mother and baby,” Franklin said.
