Change of heart: when pregnancy alters the cardiovascular system

From the moment of conception, women embark on a nine-month journey filled with endless body transformations. While some of these alterations are visible, like a protruding belly and swollen ankles, there are plenty of changes going on inside the body. The heart is not excluded. In some rare instances, healthy pregnant women can develop a life-threatening heart condition called peripartum cardiomyopathy.

Reynaria Pitts, MD, a cardiologist at HCA Healthcare affiliate North Suburban Medical Center weighs in on normal changes to the heart during pregnancy, versus the potentially fatal heart disorder.

Cardiologist, Reynaria Pitts, MD

Normal changes to the cardiovascular system during pregnancy

The heart works hard to support a pregnancy. The American College of Cardiology touts this phenomenon as “nature’s stress test on the heart.” During the first trimester, a woman’s cardiac output can increase by 50 percent to foster blood flow to various organs during pregnancy. Their heart rate can increase by 10 to 15 beats per minute during pregnancy. And, by the end of pregnancy, the uterus alone is receiving one-fifth of the woman’s pre-pregnancy blood supply.

What is peripartum cardiomyopathy (PPCM)? 

Peripartum cardiomyopathy (PPCM), also known as postpartum cardiomyopathy, is a rare type of heart failure that happens towards the tail end of a pregnancy or up to five months after giving birth. With PPCM, the heart muscle weakens and the person’s heart is no longer able to pump blood efficiently, which affects other organs in the body.

PPCM symptoms mimic typical heart failure symptoms. This can make the condition challenging to detect in pregnant women, as the symptoms are similar to the normal symptoms of pregnancy. When an individual’s heart isn’t able to pump blood correctly, buildup can cause fluid in the lungs, leading to shortness of breath and even swelling in the legs.

Healthy pregnant women can also experience swelling, shortness of breath and weight gain. This means it’s really important for pregnant women to listen to their bodies and seek medical attention if their symptoms become severe. If something doesn’t feel quite right, if symptoms feel out of proportion, talk to a doctor immediately. 

Symptoms of peripartum cardiomyopathy (PPCM) include:

• Shortness of breath (especially when lying flat)
• Swelling in the ankles
• Fatigue
• Swollen neck veins
• Increased nighttime urination
• Low blood pressure (may drop when standing up)

Who does peripartum cardiomyopathy generally effect?

Each year, about 1,000 to 1,300 women develop PPCM. This uncommon type of heart failure typically affects women of childbearing age. The affected population ranges from young adulthood to women in their 30s and 40s.

What causes PPCM?

Like many cardiomyopathies, there is no known underlying cause of PPCM. It is believed that there may be some genetic links. Those who are genetically pre-dispositioned for congestive heart failure or cardiomyopathy are possibly steered toward PPCM due to being pregnant. The added stress to the heart from pregnancy in general, with the increased blood volume, may put them into heart failure or myopathy.

What are the risk factors of PPCM?

There are no definite risk factors that lead to women being diagnosed with PPCM. In other words, there is not one single item that puts women at risk for this rare condition. PPCM tends to affect the younger, minority patient population in larger numbers. A study published in JAMA Cardiology revealed that women of African American descent were more likely to receive a diagnosis of peripartum cardiomyopathy at a younger age (27.6) compared with women of other ethnic backgrounds (31.7).

Once things like alcohol abuse or a history of cocaine or methamphetamine use are ruled out, and there is nothing else other than the patient being pregnant or recently pregnant, the condition is typically diagnosed as peripartum cardiomyopathy.

How is the life-threatening heart condition diagnosed?

A doctor is on the lookout for any signs of excess fluid, most noticeably in the lungs and feet. Collaborative care by both an obstetrician and cardiologist is essential for the resolution of PPCM.

An obstetrician typically is alerted that something is going on if their patient’s symptoms – shortness of breath, weight gain, swelling- are out of proportion. The patient is then referred to a cardiologist who will make the official diagnosis by echocardiogram, which would reveal a weakened functioning of the heart, and in coordination with the patient’s OB-GYN, a treatment plan would be developed through the birth of the child and beyond.

Treating PPCM

The cardiovascular dysfunction is treated by medications prescribed by a cardiologist.

Medications include:

• Beta blockers – to slow down the heart to give it a chance to rest and recover.
• ACE (angiotensin-converting enzyme) inhibitors – to help the heart work more efficiently.
• Mineral corticoid antagonist– to reduce fluid retention.

If the patient takes the medications appropriately and continues to take them, they have a very good chance of recovering and their cardiomyopathy may normalize. Many women recover.

A doctor might recommend lifestyle changes such as consuming a heart-healthy diet, reducing sodium intake and restricting the volume of fluids one ingests on a daily basis. In rare cases, women may need more serious treatment, such as mechanical intervention or a transplant.

 Is it safe for women with PPCM to have more children?

If a patient decides to get pregnant again after recovering 100 percent from PPCM, there is a very high risk they could have recurrent cardiomyopathy. And, even then, some of the medications that made recovery possible previously, cannot be taken during pregnancy. If a person decides to give pregnancy another try, both patients and their physicians need to be very cautious and continuously monitor for a subsequent abnormally functioning heart.

Advice for all pregnant women 

It cannot be stressed enough for pregnant patients to be aware of peripartum cardiomyopathy symptoms and to talk to their doctor about any concerns that appear (or feel) outside of “normal” pregnancy symptoms.

It’s equally important to mention any family history of congestive heart failure and cardiomyopathy to their OB-GYN.

PPCM can have great outcomes if diagnosed and treated early and devastating outcomes if one ignores their symptoms.

February is American Heart Month. Reynaria Pitts, MD, is an interventional cardiologist with HealthONE’s North Suburban Medical Center, an affiliate of HCA Healthcare, located in Thornton, Colorado.