Case study - Postpartum dyspnoea

A common symptom of normal pregnancy could spell trouble and should not be overlooked, explains Dr Zara Aziz.

In cardiomyopathy the heart may be weakened and enlarged
In cardiomyopathy the heart may be weakened and enlarged

Anna was a previously fit 35-year-old who had given birth around three weeks ago to her fourth child. She had normal deliveries with uneventful pregnancies. This time it was a home birth and both mother and baby were doing well until now.

She presented to the Monday morning surgery with a three-day history of increasing shortness of breath. She also had some ankle oedema and though she remembered her ankles being swollen during pregnancy they seemed to have become worse.

Her last haemoglobin level was 10.1g/dl soon after having her baby and she was taking iron tablets.

On examination, Anna was apyrexial with clear lungs. Her cardiovascular examination revealed an S3 gallop rhythm and elevated jugular venous pressure. Her BP was 152/90mmHg with a pulse of 92 beats per minute.

She was tachypnoeic and the pulse oximeter showed her oxygen saturation to be 90 per cent. She also had some bilateral pitting ankle oedema but her calves were not tender or swollen.

Further investigations
My initial thoughts were of a pulmonary embolus. I gave her oxygen and urgently referred to hospital. She had further tests including an ECG, which was normal, D-Dimer, which was elevated, and a chest X-ray, which showed cardiomegaly and venous congestion.

A CT pulmonary angiogram did not reveal any emboli. An echocardiogram confirmed a significantly impaired left ventricular function.

She was managed with heart failure treatment and her symptoms improved considerably. She was discharged within a few days on furosemide, spironolactone, lisinopril and carvedilol.

Anna attended cardiology follow-up six months later and underwent a repeat echocardiogram, which showed stable left ventricular function. She continues to be managed medically.

Left ventricular dysfunction
Peripartum cardiomyopathy is defined as left ventricular dysfunction (ejection fraction of less than 45 per cent) and subsequent heart failure in late stages of pregnancy and early postpartum period.

No other cause for the cardiomyopathy must have been found for the diagnosis to be made. The aetiology of the condition is poorly understood, though there is a link to an increase in inflammatory markers.

Some studies have suggested that this is a form of myocarditis caused by an autoimmune or infectious process.

Risk factors include multiple pregnancies, obesity, previous cardiac problems, smoking and malnutrition. It can occur at any age but is more common after 30. Women can present with pre-eclampsia, signs of heart failure or there can be a suspicion of thromboembolism.

Around 60-70 per cent of women experience shortness of breath in normal pregnancy and some even in the postpartum period, so this needs to be looked at with other signs.

Peripartum cardiomyopathy is treated with diuretics, ACE inhibitors and beta-blockers.

There is also a wide variation in how the disease will run its course. Around 50 per cent of women will recover full left ventricular function if treated early and are also likely to have better outcomes in future pregnancies. The remaining patients have high rates of morbidity and mortality.

Women who regain left ventricular function may still have less reserve when placed under any haemodynamic stress.

The condition also poses risk to the fetus as there is an increased incidence of premature and low birth weight babies in these women.

All women will need counselling on recurrence risks when planning further pregnancies.

It is important to consider the diagnosis of peripartum cardiomyopathy in all at-risk women with unexplained symptoms and seek early advice from obstetricians and cardiologists.

Resource

Abboud J, Murad Y, Chen-Scarabelli C, Saravolatz L, Scarabelli TM. Peripartum cardiomyopathy: a comprehensive review. Int J Cardiol 2007; 118: 295-303.

Have you registered with us yet?

Register now to enjoy more articles and free email bulletins

Register

Already registered?

Sign in

Before commenting please read our rules for commenting on articles.

If you see a comment you find offensive, you can flag it as inappropriate. In the top right-hand corner of an individual comment, you will see 'flag as inappropriate'. Clicking this prompts us to review the comment. For further information see our rules for commenting on articles.

comments powered by Disqus