When the heart fails due to pregnancy

Charlotte* was the quintessential career woman in her mid-thirties, with no sign of slowing down any time soon. Her daily schedule started at five in the gym, coffee at 6.30am, and she was at her desk at seven. She would end her day at seven as darkness fell over the city, with a brisk 30-minute walk at home before turning in. 

Charlotte was a stickler for time. She scheduled her appointments at exactly 2pm on Thursdays, coming in twice a year for wellness checks and an update, or rather, the lack of it, with regard to her fertility desires. Charlotte did want to be a mum, but she was not making progress in meeting the future father of the baby. We often joked that he would have to present himself to her office since her social life was all but non-existent. 

Well, the joke did turn into reality when she had to meet one of the company’s potential clients right in her office. Unfortunately, the contract did not materialize, but she was not able to get rid of Charlie*, who wouldn’t take no for an answer, until she had dinner with him. Fast-forward to barely a year later, Charlotte was on the way to motherhood at the age of 37. 

The twice-a-year appointments turned into monthly ones, then bimonthly, and finally weekly. Charlotte kept up with her gym regimen throughout her pregnancy, getting off the high impact exercises and working more with weights and building muscle, and finally winding down to walks and stretches. At 39 weeks, Charlotte had a smooth delivery after a grueling nine hours of labour. Mother and baby did great and were discharged on the second postnatal day. 

A week later, at the postnatal clinic, Charlotte was already gearing up to start her walks as a first step to rebuilding her exercise regimen. She was looking great, even with the sleep deprivation. Her physical examination was perfect and her uterus was shrinking back to the non-pregnant size rather rapidly. Thankfully, she also had plenty of breastmilk and the baby was calm. She left the clinic with an appointment schedule of five weeks later, marking the end of the postpartum period at six weeks. 

Two weeks later, Charlie woke me up at five in the morning. He was a nervous wreck. He told me that Charlotte had not been feeling very well the past two days, and had attributed it to the lack of proper sleep as the baby had been a bit grumpy at night. She had gotten out of bed an hour before, hoping to do a light workout as the baby slept, at her home gym. This was not to be. 

Charlie noted that Charlotte struggled to get into her gym clothes, and when she stood up after lacing her shoes, she felt dizzy and momentarily passed out, collapsing on the bedside carpet. I asked Charlie to get her to the emergency department immediately as I scrambled into my own joggers to meet them there. 

It was a whirlwind of a morning as Charlotte was received at the emergency department, underwent a battery of tests and was eventually diagnosed with possible peripartum cardiomyopathy. Off she went, to the intensive care unit for multidisciplinary care under the cardiology team. 

Peripartum cardiomyopathy is heart failure that is diagnosed in the period between the last few weeks before delivery, and the first few months after delivery. In the majority of patients, it is diagnosed in the first month post-delivery. For this diagnosis to be made, all other causes of heart failure must first be excluded. 

The cause of peripartum cardiomaypathy is not known, but it is thought to be triggered by multiple factors affecting the woman’s body at a time that it is undergoing multiple physiologic changes at the end of pregnancy. These factors appear to work in concert for the development of the condition. 

They include the rising prolactin hormone levels necessary for breastfeeding; secretion of certain chemicals by the body and the placenta, which have been shown to be injurious to the muscles of the heart (myocytes) and the inner lining of the heart and blood vessels (endothelium); genetic susceptibility to the condition due to mutations; malnutrition, including iron and selenium deficiency; previous chemotherapy for cancer treatment; and viral infections of the heart muscle causing inflammation.

This pregnancy complication occurs in one in 1,000 to one in 4,000 women having live births. It is more common in black women; in women above the age of 30; and in those who suffer pregnancy-associated hypertension. The estimated risk of dying from this condition depends on the severity of the disease and access to specialised care. 

Mortality rate

As a result of these variations, mortality rate from peripartum cardiomyopathy ranges from two per cent to 50 per cent around the world. Approximately half of the women who get peripartum cardiomyopathy will recover within six months, while the rest will require long-term cardiac care on medications, including up to a heart transplant where available. For those who recover fully, half of them may have a recurrence of the same in the next pregnancy. 

For mothers diagnosed in the antenatal period, the care is focused on both the mother and the unborn baby. Choice of drugs is made in the best interest of the mother’s health and where possible, delivery of the baby is expedited to reduce the burden on the mother’s heart. Thankfully, in most cases, the pregnancy is almost always in the last month and the baby has a fighting chance even when delivered earlier. 

In the patient being diagnosed in the postpartum care, treatment may be a little easier as there are no drug restrictions. The focus is to reduce the burden on the heart that has to pump blood out by reducing the volume of the blood and by reducing resistance in the blood vessels; and increasing the pumping strength of the weak heart. 

Ongoing research is looking at the possibility of reducing prolactin levels in the body using existing drugs. This works for women who may not have a surviving baby as it literally knocks out breastmilk production alongside. 

Charlotte thankfully made it out of the intensive care unit and finally out of the hospital in three weeks. She eventually made full recovery, being given a clean bill of health seven months later. It has been five years and she has not built the courage to put her heart through the test again. Let’s just say, Charlie strongly agrees with the euphemism that two birds in hand are worth a whole more than any unborn ones!

 Dr Bosire is a gynaecologist/ obstetrician