Peripartum cardiomyopathy: when the heart weakens around childbirth

What is peripartum cardiomyopathy?

The heart muscle, especially that of the left ventricle, contracts less well. The ejection fraction, which measures the heart’s pumping strength, is usually below 45%. The disease occurs towards the end of pregnancy or in the months after childbirth, and the diagnosis is only made after other causes of heart failure have been ruled out.

Its exact cause is not fully known. Several mechanisms are being studied, including hormonal, vascular and genetic ones.

Who is most at risk?

Frequency varies widely between regions. Hospital studies in Nigeria report up to about one case per 100 deliveries, one of the highest published rates, whereas it is much lower in Europe or Asia. However, there is no population-based study in Africa, and these figures should be read with caution.

The main associated factors are:

• African origin;
• being over 30;
• pre-eclampsia and high blood pressure during pregnancy;
• multiple pregnancies, such as twins;
• several previous pregnancies;
• severe anaemia.

The disease can, however, affect a woman with none of these factors.

What signs should raise concern?

Signs that are easily confused

Fatigue, some breathlessness and swollen ankles are common in late pregnancy. This is why the disease is often recognised late. Certain signs should prompt a medical visit:

• breathlessness on light exertion, or that is getting worse;
• needing to sleep sitting up or with several pillows;
• waking at night short of breath;
• very swollen legs or rapid weight gain;
• a persistent cough, especially when lying down;
• palpitations or chest pain.

Emergency signs

Severe breathing difficulty at rest, frothy sputum, intense chest pain, fainting or loss of consciousness require calling emergency services immediately. Sudden weakness on one side of the body or pain in a swollen leg can indicate a clot: this is also an emergency.

How is the diagnosis made?

Heart ultrasound

Echocardiography is the essential test. It measures how strongly the heart contracts, looks for a clot in its chambers and poses no danger to the baby.

Other tests

An electrocardiogram helps to rule out other causes, such as a heart attack. A blood test measuring BNP or NT-proBNP helps to confirm heart failure: a low level makes it unlikely. Other tests may be requested depending on the situation, to tell this disease apart from a pulmonary embolism, severe pre-eclampsia or a heart disease already present before pregnancy.

How is it managed?

Treatment adapted to pregnancy and breastfeeding

Treatment relies on heart failure medicines, chosen by the cardiologist according to whether the patient is pregnant, has given birth or is breastfeeding. Some heart medicines are forbidden during pregnancy because they carry a risk for the baby. A treatment should therefore never be started or stopped without medical advice.

Preventing clots

In some situations, particularly when the heart is very weak, doctors prescribe an anticoagulant to prevent clots from forming.

Other treatments depending on the case

A medicine that blocks milk production, bromocriptine, is sometimes offered after childbirth by specialist teams, with appropriate monitoring. The most severe forms require intensive care.

Childbirth and breastfeeding

Childbirth should be prepared by a team bringing together obstetricians, cardiologists and anaesthetists. Delivery before term is only considered if the life of the mother or child is under threat. For most women whose condition is stable, breastfeeding remains possible; in severe forms, it is discussed with the medical team.

What is the outlook and follow-up?

More than half of women regain normal heart function, usually within a year of diagnosis. Follow-up with ultrasound is essential, even when the patient feels better, because the disease remains serious: mortality varies between countries and with care conditions, and it is higher where access to care is limited.

A further pregnancy must always be planned with the cardiologist. The risk of relapse exists even after full recovery, and a further pregnancy is advised against when the heart remains weak. Suitable contraception should be discussed before leaving the maternity ward.

Frequently asked questions