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Management Strategies
Preconception counseling/Contraceptive methods
Severity of aortic stenosis and function of the left ventricle are important determinants of outcomes during pregnancy. Women who with a history of heart failure or arrhythmias are at higher risk for complications during pregnancy. Other cardiac characteristics can also have an impact on outcomes (see General Considerations).
Women with severe symptomatic AS should be considered for intervention prior to pregnancy. In asymptomatic women, time of intervention needs to be tailored to the individual.
A discussion about contraceptive methods is appropriate in women with aortic stenosis. In general, most forms of contraception are safe in women with AS. (see Contraception)
Transmission of congenital heart disease to offspring should be discussed. The risk of transmission of congenital heart disease is approximately 10%, compared to a background risk of approximately 1% of having a baby with congenital heart disease.
Medication use should be reviewed if a woman is contemplating pregnancy or is pregnant. The MOTHERISK website is an excellent resource.
Given the aortopathy associated with bicuspid aortic valve, some experts suggest therapy with beta-blockers during pregnancy in women whose aortas are dilated to reduce the chance of aortic root dilation or dissection.
Ante-partum Care
Coordinated care between a congenital heart disease specialist and a high-risk obstetrician at a high-risk pregnancy center should be implemented. The frequency of follow-up visits and echocardiograms should be dictated by women’s functional status and the severity of her AS.
Women with significant AS require close follow up by a dedicated multidisciplinary team of experienced cardiologists, high-risk obstetricians, and anesthetists.
Women who develop cardiac symptoms, have a decrease in left ventricular systolic function, or have a fall in the peak aortic velocity, may need to be considered for intervention. Initial therapy should include bed rest, treatment of aggravating factors such as anemia, and treatment of heart failure or arrhythmias. Interventions, specifically valvuloplasty or valve surgery may be needed in women with refractory symptoms. These procedures should only be performed by operators and in certers with expertise in the procedures. Valvuloplasty during pregnancy exposes the fetus to radiation. Special attention should be given to minimizing radiation exposure in the fetus by shielding the gravid uterus and keeping fluoroscopy time to a minimum. Cardiopulmonary bypass surgery for aortic valve replacement during pregnancy carries a high risk of fetal loss.
All women with congenital AS should be offered fetal echocardiography at 20 weeks gestation.
Labour and Delivery
Labor and delivery should be planned carefully with a multidisciplinary team well in advance. It is important to communicate the delivery plan to the woman and to other physicians involved in her care. The best delivery plan is not useful if information is not readily available when needed.
Generally, vaginal delivery is recommended. Good pain management for labour and delivery is important in order to minimize maternal cardiac stress. Care should be taken to avoid drops in blood pressure that can occur with anesthesia. To decrease maternal expulsive efforts during the second stage of labour, forceps or vacuum delivery is often utilized. To decrease potential harmful complications from difficult mid cavity-assisted delivery, uterine contractions are often utilized to facilitate the initial descent of the presenting part.
The need for maternal monitoring is dictated by the severity of AS and functional status of the women. Women with significant AS may require invasive blood pressure monitoring.
In general, endocarditis prophylaxis at the time of labour and delivery is not recommended in women with AS. However, some experts continue to administer antibiotics because they feel that the risks of adverse reactions to antibiotics are small and the risk of developing endocarditis has major health consequences.
Post-partum Care
The hemodynamic changes of pregnancy may take up to six months to normalize. Women should be seen early after pregnancy (usually within 6-8 weeks). The frequency of additional follow up visits should be dictated by the clinical status of the women. Because women with moderate or severe AS can develop symptoms de novo after pregnancy, extended postpartum follow up is important.
