What is heart failure during pregnancy?
The term heart failure refers to situations in which the heart cannot circulate enough blood to meet the needs of the body. Not enough blood moves quickly enough to where it needs to go, and there is a backup of fluid upstream from the part of the heart that is failing. Usually, heart failure involves the left ventricle (left ventricular failure, left heart failure), and soon after that also the right ventricle (right ventricular failure, right heart failure). This is because dysfunction of the left ventricle causes fluid to accumulate in the lungs (congestive heart failure), thus increasing the pressure against which the right ventricle must pump, so pressure and fluid build-up in the right ventricle, which enlarges and weakens. Known as cor pulmonale, this situation that leads to right heart failure also can occur if there is a problem in the lungs, not due to a problem in the left ventricle. Consequently, right heart failure can occur without left heart failure, whereas left heart failure quickly becomes failure of both ventricles. Whatever the cause of right heart failure, blood backs up in the bodys veins, which causes swelling (known as edema) that is most obvious in the legs, ankles, and abdomen.
Left ventricular failure is called systolic failure when the problem is that the heart muscle does not contract strongly enough to pump out the blood that has filled it. This can happen, because the muscle is weak, or because there is resistance downstream from the ventricle, such as high blood pressure in the arteries, or that the aortic valve (the valve leading out from the left ventricle to the largest artery, the aorta) is stenotic (narrowed). In contrast, there is diastolic failure, in which the ventricle cannot relax enough after it has finished contracting, so it does not fill up with enough blood, meaning that when its time to contract, there isnt enough blood to pump out of the ventricle, no matter how strongly it is able to contract. Either situation leads to a vicious cycle since there is not enough blood coming from the ventricle through the aortic valve and to the coronary arteries that supply the heart itself, so the heart weakens more.
Heart failure can result from any of a variety of preexisting cardiac conditions that can worsen in pregnancy due to the increased cardiovascular demands as the pregnancy progresses. Alternatively, heart failure can result from certain complications that are specific to pregnancy, namely preeclampsia, amniotic fluid embolism (AFE), and peripartum cardiomyopathy.
How common is heart failure during pregnancy?
Heart failure is fairly rare in pregnancy, with one recent study reporting a rate of 112 cases per 100,000 pregnant women being discharged from the hospital for pregnancy-related issues.
How is heart failure during pregnancy diagnosed?
Initially, there are symptoms, such as dyspnea (breathing trouble) that can give doctors a clue of possible congestive heart failure, and swelling of your legs and abdomen, along with signs on the physical examination, such as sounds indicating lung congestion when the examiner listens to your lungs with a stethoscope. While sounds from the lungs, as well as the heart, can be revealing, medical technology is reaching a point where results from imaging procedures overshadow physical findings. A chest x-ray revealing that the heart is enlarged, particular findings on electrocardiography (ECG) and a stress test (ECG, while you exert yourself) add more information, plus blood samples of yours will be tested for a substance called pro-B-type natriuretic peptide (NT-proBNP), which builds up in the blood during heart failure.
Other tests include magnetic resonance imaging of the heart (cardiac MRI), coronary angiography, and myocardial biopsy (sampling of the heart muscle) through a device that is inserted through a vein in your thigh. Your medical history will determine various other tests. They will include workups for various causes of heart failure outside of pregnancy as well as for particular pregnancy complications that can cause heart failure, such as preeclampsia, and especially amniotic fluid embolism (AFE) and peripartum cardiomyopathy. In the course of assessing your condition, a cardiologist will classify the severity of your heart disease, using a classification system, such as the New York Heart Association (NYHA) classification.
Does heart failure cause problems during pregnancy?
The level of problems depends on the severity of your heart failure. If you are Class I in the NYHA system, you are free of symptoms. If you are Class II, you may get tired with activity and as pregnancy advances. In Class III, normal daily activities can be challenging as can pregnancy, while in Class IV, even when resting, you feel tired and have trouble breathing. With Class III and IV, pregnancy entails some danger to your life.
Does heart failure cause problems for the baby?
Yes, because heart failure can be fatal to the mother, there is an extreme risk of fetal death.
What to consider about taking medications when you are pregnant or breastfeeding:
- The risks to yourself and your baby if you do not treat the heart failure
- The risks and benefits of each medication you use when you are pregnant
- The risks and benefits of each medication you use when you are breastfeeding
What should I know about using medication to treat heart failure during pregnancy?
Medication is an extremely important component of treatment for heart failure, but the choice of medication depends greatly on the type of heart failure. The type of drugs that are given to confront heart failure include angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (both useful for systolic heart failure), beta-blockers (to reduce blood pressure and allow more filling of the ventricles, which increases the force of contraction), diuretics (to lower blood pressure by reducing blood volume), and inotropes, such as digoxin and digitalis, increase the strength of heart muscle contractions and also slow the heart (useful in systolic heart failure). Certain of these drug categories are contraindicated in pregnancy – ACE inhibitors, for instance, cannot be given because they are toxic to the fetal kidney. In contrast, others, such as beta-blockers, can be taken. If you are on certain cardiac medications, you may need medication changes when you become pregnant.
Who should NOT stop taking medication for heart failure during pregnancy?
If you need medication for heart failure, stopping the medication can lead to a rapid decline in your condition. As noted earlier, however, medications that you have been taking for heart failure prior to pregnancy may need to be changed.
What should I know about choosing a medication for my heart failure during pregnancy?
It is important to stay in communication with your health care provider as the release of new studies over time can change the outlook on the role of specific medications during pregnancy.
You may find Pregistrys expert reports about the medications to treat this condition here. Additional information can also be found in the sources listed below.
What should I know about taking a medication for my heart failure when I am breastfeeding?
Generally, the concern about the harmful effects of medications on the nursing neonate is less compared with the concern about medications affecting the fetus during pregnancy. Unlike during pregnancy, ACE inhibitors are not contraindicated. Within each category of drugs, however, there are preferences, based on what is known or unknown about the medications entering breastmilk.
Based on available evidence, among ACE inhibitors, enalapril is preferred compared to other ACE inhibitors, such as lisinopril. In the case of beta-blockers, propranolol and metoprolol are considered safe during breastfeeding. When it comes to digoxin, it has been reported to enter breastmilk, but in very small amounts, so it is also thought to be safe when you are nursing.
What alternative therapies besides medications can I use to treat my heart failure during pregnancy?
There are additional measures that you can take alongside medications. These measures include lifestyle changes, such as reducing your intake of dietary salt to reduce the accumulation of fluid in body tissues, and the use of compression stockings to offset swelling in your legs, which helps fluid return to the heart. However, medications are vital when you have heart failure since the heart is in a downward spiral. Since medication can only slow the progression of the disease, the only cure is a surgical procedure, namely heart transplantation. This is not a procedure that can be performed during pregnancy, and it typically entails periods of waiting until a donated organ that is a good match for you becomes available. On the other hand, there is an increasing number of what are called ventricular assist devices that help your heart pump more strongly. As progress continues, these devices may amount to long-term treatments.
What can I do for myself and my baby when I have heart failure during pregnancy?
Follow the instructions of your physician. Report any side effects that you feel from your medications immediately.
Resources for heart failure in pregnancy:
For more information about heart failure during and after pregnancy, contact http://www.womenshealth.gov/ (800-994-9662 [TDD: 888-220-5446]) or contact the following organizations: