Preconceptional evaluation of women with heart disease
Women of reproductive age with existing heart disease require evaluation in the preconception period, with unique implications for treatment options. Historically, rheumatic heart disease was the most prevalent heart condition in women of reproductive age; however, the advancements in healthcare in recent years, particularly cardiac surgery, have led to a much larger proportion of women with congenital heart disease (CHD) in this population of women (34, 35).
This section will focus on discussion of preconceptional evaluation for women with the two most common heart disease burdens in pregnant women: CHD and valvular heart disease (VHD).Although CHD is now the most prevalent heart disease for women in pregnancy, they also have relatively favourable outcomes in regards to maternal mortality, cardiac complications, preterm birth, low birth weight, and neonatal mortality (34). Interestingly, statistics show that caesarean delivery rates are still high in this population; however, in most cases of CHD, spontaneous vaginal delivery is recommended (36). There are specific cases in which caesarean section is recommended, including severe pulmonary stenosis and ventricular function deterioration, and discussion of this should be considered in the preconceptional period (36).
VHD is the second most prevalent heart disease among women of reproductive age. Unfortunately, many women with VHD are not aware of their diagnosis prior to conception, and therefore preconceptional counselling is often limited. In cases where VHD is diagnosed prior to conception, preconceptional evaluation is important to identify the modifiable risk factors that confer a poor outcome, including functional capacity of the individual, ventricular systolic function, and the presence of pulmonary hypertension. Preconceptional evaluation includes a baseline cardiovascular stress test and screening tests with electrocardiography and echocardiography in order to detect these modifiable risk factors.
In cases where valvular surgery is indicated, preconceptional counselling is paramount regarding the timing of the surgery, as well as the resulting implications of treatment following the interventions of bioprosthetic versus mechanical valve replacement. Management of women in pregnancy with mechanical heart valves is exceedingly difficult and controversial, as they require long-term anticoagulation; however, there is no ideal regimen that balances the risks and benefits to both mother and fetus (37-39). The trade-off with bioprosthetic valves is the limited lifetime of the valve, often requiring replacement at least once in a patient's lifetime. In cases where valve replacement is indicated, there is no clear consensus on the recommendations, as the individual case should be discussed and managed by a cardiologist with specialties in management of pregnancy in conjunction with an obstetrician. The most common perinatal complication in women with VHD is heart failure, with an increased incidence of postpartum haemorrhage, most likely observed due to the increased use of anticoagulants in this population (34). However, despite the high rates of morbidity in pregnant women with VHD, mortality remains low (40).