Rapid advances in heart disease diagnosis and treatment now enable most pregnant women with heart conditions to carry their pregnancies to term. However, heart disease remains a leading cause of maternal mortality, presenting a significant challenge for both expectant mothers and obstetricians.
Approximately 1% of all pregnant women have heart disease, primarily rheumatic heart disease and congenital heart disease, occurring in roughly equal proportions. Rheumatic heart disease most commonly affects the mitral valve, potentially requiring artificial heart valve replacement surgery; congenital heart disease is most frequently associated with ventricular septal defects.
During pregnancy, physiological changes in the cardiovascular system often place additional strain on the heart. Furthermore, labor pains, pushing efforts, and physical exertion during childbirth all increase cardiac workload. If the heart was already compromised, this can lead to cardiac overload, potentially endangering the lives of both the mother and fetus.
Pregnancy feasibility depends on cardiac health status. For expectant mothers with heart disease, pregnancy outcomes correlate closely with cardiac function classification.
First: No heart disease symptoms, unrestricted physical activity, and no discomfort during routine activities.
Second: Physical activity is slightly restricted. No discomfort at rest, but fatigue, palpitations, angina, and shortness of breath occur during routine activities.
Fourth, discomfort occurs with any activity, and cardiac symptoms are present even at rest, worsening with any physical exertion.Although fetal mortality rates do not increase in mild heart disease cases, preterm birth and intrauterine growth restriction occur more frequently than in normal pregnancies. Additionally, the risk of congenital heart disease inheritance in the next generation increases. Studies indicate that if either parent has congenital heart disease, the risk of their offspring developing it reaches 1.8%.
Cardiac function classification is a critical factor in determining whether an expectant mother can deliver safely. Typically, women with Class I and most Class II heart conditions can deliver without complications. For women with Class III heart disease, one-third experience cardiac decompensation and failure during pregnancy, making long-term bed rest in a hospital setting advisable. Women with Class IV heart disease should avoid pregnancy. If pregnancy has already occurred, early termination should be considered.