Cardiac Disorders in Pregnancies

Pregnancy in heart disease is rare but can carry with it significant risks to the mother and the fetus. The prevalence of this condition is approximately 1-5% of pregnant women. The most common cardiac conditions ranges from congenital heart defects like mitral valve prolapse to rheumatic heart disease.

With advances in surgical techniques for congenital hearts defect correction as well as the common heart valve replacement procedures, more females survive their condition and the incidence of women of childbearing age with cardiac concerns are increasing. Problems like pulmonary hypertension, Marfan syndrome and cyanotic congenital heart disease form the highest risk group.

Due to the low prevalence and complicated nature of their cardiac conditions, it is therefore needful that these patients receive specialised care in pregnancy. A team of specialist that consists of the obstetricians, cardiologist, anaesthetist as well as the neonatologist should coordinate the care for such patients.

In pregnancy, there are increased demands made by the fetus as well as the pregnancy hormonal changes. This causes a significant increase the amount of blood pumped out of the heart (cardiac output). At rest, cardiac output will increase by 50% from 4 L/minute to 6 L /minute in early pregnancy. During labour, the cardiac output may rise further due to pain and exertion and decreases by 2 weeks after delivery. As such, problems like palpitations (sensation of fast beating heart) and high blood pressure are common during pregnancy. These problems if untreated may lead maternal and fetal problems. Up to 8% of normal gestations may be affected by hypertensive disorders in pregnancy. Some patients with congenital heart defects may be diagnosed for the first time due to the hemodynamic stresses of pregnancy.

Pregnant women may be at increased risk of thromboembolism due to hormonal effects, enlarging uterus and reduced mobility and thus, the issues of anticoagulation for pregnant women with mechanical heart valves are of a concern to the cardiologist. The drugs used for thinning of the drugs must be carefully selected and kept at optimal levels during pregnancy, as different drugs carries a different risk. Other issues like abnormal heart rhythms or having a high risk of having infection in the heart (endocarditis) needs to be watched closely as well.

Female patients with a congenital heart defect carry a 2.5% to 18% risk of having a child with congenital heart disease ranging from a simple lesion to a very complicated heart abnormality. Some rare genetic abnormality have a 50% risk of transmission to the next generation (Marfan Syndrome and the 22Q11 deletion syndrome). Thus, genetic counseling of the patient and spouse should take place before conception.

Most doctors are not familiar with the changes that a patient undergoes during pregnancy and the drug therapies which can be employed. Even fewer are familiar with congenital heart disease. Many patient’s may have been falsely led to believe that they should never conceive due to risk to their well being and their offspring. The care and management of each patient is catered according to the condition of the patient would defer from patient to patient.

In conclusion, pregnancy in heart disease is rare but needs special attention when it occurs. It needs to be managed by a team of dedicated specialist familiar with its care.

Who Should Be Referred

• All women with pre-existing cardiac conditions or congenital heart disease. (Male spouses with congenital heart defects can be referred for genetic counselling)
• Cardiac symptoms during pregnancy (like palpitations, chest pain, breathlessness)
• Hypertension during pregnancy.

The National University Hospital hosts a specialised cardiac clinic for pregnant women with heart disease. Our team of doctors with special interest in pregnancy in heart disease comprises :

• Cardiologist
  Primary physician in charge: Dr James Yip, Consultant
  For appointments, please call (65) 6772 2092
  
  
• Obstetrician
  Private Consultation:
  - A/Prof Arijit Biswas, Senior Consultant, Obstetrics and Gynaecology
  - A/Prof Mary Rauff, Senior Consultant, Obstetrics and Gynaecology
  - A/Prof Y C Wong, Senior Consultant, Obstetrics and Gynaecology
  - Dr Mahesh Choolani, Consultant, Obstetrics and Gynaecology
  
  For appointments, please call (65) 6772 2255 / 2277
  
  
• Subsidised care:
  Registrar on duty
  
  For appointments, please call (65) 6772 5503

Read more about :

• Pregnancy and heart disease