Antenatal care of the pregnant woman with heart disease

Dateline: 09/07/98

Pregnancy is one of the physiological conditions that places a considerable burden on the heart, forcing it to work harder for a significantly long period - nine months. While a normal heart is quite capable of taking this extra workload right in its stride, a diseased one may not be able to cope. Different kinds of heart disease may cause different problems during pregnancy. In this series of articles I plan to discuss this topic in depth.

Antenatal Care of pregnant women with heart disease

The focus of care early in pregnancy is on avoiding risk factors including

• infection
• high blood pressure
• obesity
• multiple pregnancies
• anemia (low hemoglobin content)
• arrhythmia (disturbed rhythm of the heart)
• rarely hyperthyroidism

An ultrasound examination is done to

1. confirm gestational age
2. in congenital heart disease, to rule out fetal anomalies

When the patient is stable, no special treatment is needed. When there are signs of hemodynamic compromise, though, careful fetal monitoring is needed. Intra-uterine growth retardation (IUGR) and fetal asphyxia are the major concerns. Clinical and ultrasound examinations can assess fetal growth and amniotic fluid volume. Other tests that might be required in special circumstances are

• Cardiotocography to measure fetal heart rate
• Color doppler flow studies to measure fetal and maternal placental blood flow
• Fetal blood sampling to detect low oxygen content

If heart failure develops, admission in hospital is advisable. The principles of treatment remain the same, with digoxin and diuretics being the cornerstones of therapy. Other precipitating causes are treated like rhythm disturbances or anemia. Once heart failure is brought under control, most women can be discharged from hospital.

In the next article, we will discuss aspects of management principles of heart disease patients during the pregnancy.