What is Peripartum Cardiomyopathy?
Peripartum cardiomyopathy (PPCM) is a rare type of heart disease that can occur during the later stages of pregnancy or immediately after giving birth. This condition is serious and can pose risks to life because it weakens the heart, notably a side of the heart known as the left ventricle. It leads to heart failure, where the heart does not pump blood as well as it should.
In simpler terms, PPCM is a condition where the heart becomes weaker around the end of the pregnancy or after childbirth. It’s a bit hard to explain because it varies a lot. Back in 2010, a group of heart doctors from Europe gave a good description of what PPCM typically looks like:
– First, it shows signs of heart failure – like the heart not pumping well, fatigue, and shortness of breath – around the end of pregnancy or just after giving birth.
– Second, they can’t find another reason for the heart failure – that means, this condition has no other known cause.
– Third, a test reveals that the capacity of the left side of the heart to push out blood (the “left ventricular systolic function”) is often less than 45%. This means that heart is not pumping efficiently. The left side of the heart (the left ventricle) may or may not be larger than normal as well.
What Causes Peripartum Cardiomyopathy?
The exact cause of PPCM, also known as peripartum cardiomyopathy (a heart condition that occurs during or after pregnancy), is still not well understood. However, there is a recognized link with conditions like eclampsia (seizures during pregnancy) and high blood pressure during pregnancy.
Several factors can increase the risk of developing PPCM. These include being of African descent, being older during pregnancy, having high blood pressure related to pregnancy or in general, having multiple births, being overweight, and the extended use of medications (called tocolytics) that prevent premature labor.
While we don’t fully understand the exact cause of PPCM, there are several theories about why it might develop. We’ll discuss these possible explanations later in the text related to the condition’s progression or pathophysiology (which is a term for how the condition changes the body’s normal functioning).
Risk Factors and Frequency for Peripartum Cardiomyopathy
The rate at which Peripartum cardiomyopathy (PPCM) occurs is difficult to determine because it is often misdiagnosed. However, research has shown that the occurrence of PPCM can differ depending on the geographical location. For instance, in the United States, it’s reported that for every 4,000 live births, there is one PPCM case. However, in Nigeria, the number is significantly higher, with one PPCM case occurring in every 100 live births.
PPCM is more likely to affect women who are older than 25 years, with the average age being around 30 years. Several factors can contribute to the likelihood of developing PPCM. These include:
- Pregnancy-related hypertensive disorders
- Existence of anemia
- African lineage
However, it’s important to note that the incidence of PPCM is least common among Hispanic women.
Signs and Symptoms of Peripartum Cardiomyopathy
Peripartum cardiomyopathy (PPCM) is a heart condition that usually shows up after the 36th week of pregnancy or within the first month after delivery. If a patient has existing heart complications like a damaged valve or reduced blood flow to the heart, they may experience it earlier.
The signs of PPCM may vary depending on how advanced the disease is when it’s detected. Symptoms linked to heart failure or pregnancy include trouble breathing at night or when lying down, swelling in the feet and ankles, and feeling short of breath during physical activity. Patients may also have a persistent cough, feel their heart pounding or fluttering, notice an increase in their belly size, feel faint, or experience chest pain.
During a physical exam, doctors might find signs like full or bulging neck veins, a heartbeat that’s felt to the left of where it should be, the presence of an extra heart sound, or an unusual sound that indicates a mitral valve isn’t closing properly.
Testing for Peripartum Cardiomyopathy
Diagnosing Peripartum cardiomyopathy (PPCM), a heart condition that occurs during pregnancy or immediately after childbirth, can be challenging. This is because its symptoms are similar to natural changes that happen during pregnancy. Since PPCM is a diagnosis made only after excluding other possibilities, it requires thorough investigation to rule out other more common heart diseases. Here are some methods involved in diagnosing PPCM:
1. Routine Blood Work: This is done to rule out other causes of PPCM symptoms such as anemia (low red blood cells count), electrolyte imbalances, hormonal conditions like thyroid disease, and liver or kidney dysfunction. Doctors may also measure the levels of a hormone called brain natriuretic peptide (BNP), which is usually found in higher amounts in people with heart failure, including those with PPCM.
2. Chest X-Ray: This may be carried out to help evaluate the condition. While the findings from an X-Ray (like an enlarged heart or fluid in the lungs) are not enough to diagnose PPCM, they can suggest heart failure.
3. Heart Tests: These involve an electrocardiogram (ECG/EKG, measures heart’s electrical activity) and echocardiogram (creates pictures of the heart using sound waves).
The EKG might show a faster-than-normal heart rate, or other irregular rhythms. Dilation of heart chambers can also be seen on EKG. However, these are not specific to PPCM. A prolonged QRS duration (certain reading on EKG) of over 120 milliseconds is found to be linked to increased death rates in PPCM patients.
An echocardiogram is crucial in evaluating the heart’s structure and function in suspected PPCM cases. A critical measure from this test is the left ventricular ejection fraction (LVEF, measurement of how much blood the left ventricle pumps out with each contraction), less than 45% of which is part of the criteria for diagnosing PPCM. An echocardiogram can also reveal conditions like valve diseases or other structural heart problems that could cause heart failure.
4. Advanced Heart Scans: Further heart testing via imaging scans like a cardiac MRI may be beneficial for diagnosing other heart failure causes not related to PPCM. While MRI allows for a more detailed assessment of the heart’s chambers and functioning than an echocardiogram, its specific role in diagnosing PPCM is still being studied.
5. Cardiac Catheterization: This is an invasive procedure and is reserved for selected patients. It is used to investigate suspected heart artery diseases (left heart catheterization) and measure exact pressures inside the heart in severe cases (right heart catheterization).
On the other hand, a heart muscle biopsy is generally not recommended. This is because it is most helpful in looking for infiltrative diseases (conditions where abnormal substance builds up in the heart), which can cause the heart to fail.
Currently, there are no specific tests that can diagnose PPCM directly.
Treatment Options for Peripartum Cardiomyopathy
The first step in treating peripartum cardiomyopathy (PPCM), a type of heart failure that can occur during pregnancy or after giving birth, is similar to treating other forms of heart failure. Additionally, PPCM treatment needs to take into account how the condition impacts the pregnancy and may include various strategies to manage irregular heartbeats, reduce blood clot formation, and even provide mechanical assistance for heart function. Certain experimental treatments are also being investigated.
One important goal in PPCM treatment is ensuring that the body’s fluid levels are well-managed. This is typically achieved by using medications that increase urine output (diuretics) and maintaining the right balance of fluid within and outside the body’s blood vessels, ideally by limiting fluid intake. However, using diuretics during pregnancy needs to be done with caution, because they can reduce blood flow to the placenta, potentially harming the baby. Diuretics like hydrochlorothiazide and furosemide can be safe during pregnancy and while nursing, but they need to be used at low doses and under careful observation.
Two common heart failure medications, angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs), should not be used during pregnancy due to their potential to cause birth defects. These medications can be administered after giving birth, but mothers using them should not breastfeed.
Beta-blockers can be used cautiously during pregnancy; however, they should not be used during breastfeeding as they can be passed into the breastmilk. Carvedilol, which is a combination beta-blocker and alpha-blocker, can help reduce the pressure in the blood vessels and is useful in treating PPCM.
Some other heart medications like hydralazine and nitroglycerin, which help to widen blood vessels, can be used during pregnancy. However, a drug called nitroprusside should not be used due to concerns about potential harmful effects.
In extreme cases where PPCM patients are critically ill and experiencing unstable blood pressure and heart rates, medications like dobutamine, dopamine, and milrinone can be used to increase the heart’s ability to pump blood. But their usage is limited to these critical scenarios and these medications should be stopped as soon as it’s safe to do so.
Digoxin, another heart medication, can be used safely during pregnancy. It is especially useful when there is a need to increase the force of the heart’s contractions and to control a fast or irregular heartbeat, often seen in a condition called atrial fibrillation.
The use of anticoagulants, or blood thinners, in patients with PPCM can be a controversial topic. Generally, patients with PPCM who don’t have a blood clot in the heart’s left ventricle or atrial fibrillation (an irregular and often rapid heart rate) are not put on blood thinners. But those who do have these complications may need to be put on blood thinners, depending on the specific guidelines and their stage of pregnancy.
The decision to use devices like implantable cardioverter defibrillators (devices that can correct abnormal heart rhythms) or to use cardiac resynchronization therapy (a treatment that improves the heart’s rhythm) in patients with PPCM should consider their potential for heart function recovery.
Some very ill PPCM patients may require the use of mechanical support for the heart to pump better. This can be achieved using a device called a left ventricular assist device, which can be a temporary measure until a heart transplant can be performed or until the patient’s heart recovers.
Experimental medications including pentoxifylline, bromocriptine, immunoglobulin, and immunosuppressants are still being studied, and the guidelines for using these are not specifically defined yet.
What else can Peripartum Cardiomyopathy be?
PPCM, or peripartum cardiomyopathy, can only be diagnosed once other causes of heart failure are ruled out. Conditions like pre-existing heart valve diseases or already present cardiomyopathy may worsen due to the changes in blood flow that happen during pregnancy. These conditions can further develop and become more noticeable as the pregnancy progresses.
What to expect with Peripartum Cardiomyopathy
Typically, recovery after childbirth takes about three to six months, but some cases have been reported to take up to 48 months after delivery.
There are several factors which are linked to a quicker and smoother recovery. These include a smaller-than-average lower heart chamber size (measured as being less than 5.5cm), a left ventricular ejection fraction (LVEF, a measure of how well your left ventricle pumps blood) greater than between 30% to 35%, and a fractioning of shortening (how much your heart muscle shortens when it contracts) greater than 20% at the time of diagnosis. Other positive signs include no elevated levels of troponin (a protein released when the heart muscle has been damaged), no blood clots in the left ventricle, and patients who are not of African American descent.
On the other hand, certain factors may indicate a slower or more challenging recovery. These include a QRS duration (a measure of the time it takes for the electrical signal to travel through your heart) over 120 milliseconds, a delayed diagnosis, a high New York Heart Association (NYHA) classification (which measures the severity of symptoms in heart failure patients), having had multiple pregnancies, and patients who are of African descent.
Importantly, it’s worth noting that those who developed peripartum cardiomyopathy (PPCM, a type of heart failure that occurs during pregnancy or immediately after delivery) in a previous pregnancy have a higher chance of it recurring in future pregnancies. Therefore, patients should generally be advised against further pregnancies and should be regularly monitored.
Possible Complications When Diagnosed with Peripartum Cardiomyopathy
Complications that can happen to the mother include:
- Blood clots
- Irregular heart rhythms
- Worsening heart failure
- Misdiagnosing the condition as pre-eclampsia
Complications that can occur to the fetus include:
- Stress due to lack of oxygen
Preventing Peripartum Cardiomyopathy
It’s important for patients to understand that there are potential risks that may occur during pregnancy. Often, patients may feel that the doctor is at fault when a heart disease, known as cardiomyopathy, appears without any previous signs.
