Source: www.ihearteatwelllivewell.org
Everyone wants to be normal and healthy during pregnancy and have an uneventful delivery. Women with pre-existing heart disease prior to getting married are often pressured by relatives and families to bear children, which can be stressful to this group of patients. By reading this article, hopefully you will understand the consequences that mothers with underlying heart disease may face when they are pregnant.
Heart disease in pregnancy is not a contraindication for pregnancy but it all depends on the severity of the heart condition itself. The cardiologists will determine if the patient falls into a severe or mild type of heart disease by assessing their daily functional activities using the New York Heart Association (NYHA) classification. Some may need an echocardiogram assessment to visualize the defect and confirm the diagnosis. Usually, patients with mild form of cardiac conditions who are not on any heart failure medications or antibiotic prophylaxis can safely embark on pregnancy.
What happens to our heart during pregnancy?
During first trimester, there will be increased plasma volume in our body. It means that our blood volume will increase to 40 percent until 28 weeks of pregnancy. As a result, our hearts need to work harder by increasing the heart pumping rate and output. The heart has to work at its maximum force during the second stage of labour, which is during delivery or straining. A normal healthy woman’s heart can sustain this stressful condition. However, in patients with underlying heart disease, the overworked heart may fail to compensate. The patient may end up collapsing.
What should you do if you are pregnant?
Once the pregnancy is confirmed, a thorough examination will be done during booking/registration at Maternal and Child Health (MCHC) clinic to assess your condition. Haemoglobin should be optimized, preferably more than 10gm/dl to avoid increased exertion to the heart due to anaemia. Your antenatal card will be labelled as code RED. That means, you should be seen by obstetrician in tertiary hospitals, in combined clinic with cardiologist. This is to ensure that any signs and symptoms of heart failure such as shortness of breath, chest pain at night, bilateral leg swelling or bluish discolouration of the skin (cyanosis) are detected early. Echocardiography will be done every trimester to ensure the heart able to cope with the pregnancy changes. On top of that, you will need to be seen by anaesthetist to assess if you need any ICU back up later after delivery.
Can it affect my baby?
There will be risk of intrauterine growth restriction or small size baby during pregnancy due to lack of oxygen supply to the baby if your heart is not pumping well. In a severe type of heart disease, baby can end up with intrauterine death due to lack of oxygen and poor placental perfusion (lack of oxygen supply to the placenta) to the baby in the womb. If you have an inherited or congenital heart disease since childhood, your baby has 1 to 3 percent risk of inheriting the disease from you. In this type of case, early referral to fetomaternal unit for fetal detailed scan at 18 to 22 weeks is essential to screen for any possibilities of congenital heart disease to the baby. Certain heart disease may require blood thinning medication (anticoagulant) or warfarin throughout the pregnancy. These drugs can cross the placenta and a detailed scan is required during pregnancy as it may affect the fetus.
Can I deliver normally if I have heart disease?
Your cardiac condition would be assessed by cardiologist thoughout your pregnancy. That is why it is important not to miss any of the follow up appointments. They (cardiologist and obstetrician) will decide on the best timing for the delivery, preferably in a controlled and planned situation where the avaibility of the experts can be guaranteed during the delivery. In the event of worsening cardiac condition, the patient might need to deliver earlier to avoid maternal deterioration. The mode of the delivery will be decided by the doctors, depending on the type of heart disease. In severe types of heart disease, elective caesarean section would be preferred with ICU backup to prepare for any catastrophe. For those who are suitable for vaginal delivery, epidural analgesia is highly recommended to prevent additional stress during labor. Instrumental delivery need to be done in selected cases to avoid overload on the heart during straining and pushing in labour.
I have severe type of heart disease and am accidentally pregnant. What should I do?
This is one of common but difficult scenarios that can be seen in hospitals. If they are still in early trimester, the cardiologist will assess them together with their spouse. A very detailed and proper counselling will be done together with obstetrician regarding the prognosis. They should be aware that prolonging the pregnancy may risks the patient’s life and lead to maternal mortality (death). In certain conditions, termination of pregnancy may be offered for maternal health reasons. On other hand, if the couple still wish to take the risk after detailed counselling, the patient will be followed up closely by obstetrician and cardiologist monthly. Early delivery will be recommended if the patient shows any worsening of her heart condition, which could be dangerous to the patient and the baby itself.
Can patients with mild heart disease get pregnant again?
This depends on their heart condition. Adequate spacing of more than 2 years is important to give our body time to return to its normal physiological function. Usually, obstetrician will advise this group of patients to have smaller number of children as the outcome of their cardiac condition in future pregnancyies is unpredictable. Combined hormonal pills should be avoided. Intrauterine device (IUCD) is still debatable depending on type of heart disease. Progesterone containing pills, injections or implanon would suitable choices. However, please consult your obstetrician first regarding the best contraception for you, according to your heart condition.
What if I have severe type of heart disease?
In certain life threating heart conditions such as cardiomyopathy, severe mitral stenosis, Eisenmengger disease or pulmonary hypertension, pregnancy should be avoided as the pregnancy itself can cause maternal mortality (death) up to 50 percent. Usually in this type of patients, the cardiologist would refer them to gynaecologist for contraception advice. For those who have already completed their family, bilateral tubal ligation is one of the options. However one must bear in mind that during bilateral tubal ligation, the anesthesia itself is a risk, which may endanger their own life. Combine hormonal contraceptive pill is also not suitable due to its blood clotting (thrombogenic) side effects. Vasectomy for husband is the best choice.
Opppsss…. I accidentally heard a murmur!
A murmur is a turbulent sound that can be heard using stethoscope. It is a routine examination that should be done by the doctors in any clinic during booking or follow up. If your doctor heard a murmur, he or she should not forget to check for any other signs of heart disease in that patient. A murmur during pregnancy could be normal (physiological) but abnormal (pathological) murmur should be excluded too. So, for all the doctors out there, make sure you auscultate the patient’s heart properly so that you can pick up any previously undiagnosed heart disease. You will be surprised, many healthy women out there might never know that they have heart problem. Once you detect this, please do not hesitate to refer to the specialist for further investigation. Then, don’t forget to pat yourself on the back as you have already taken the first step in saving the patient’s life and prevent another maternal mortality due to heart disease.
Dr. Mardiana Kipli M.D (UNIMAS) is an Obstetric & Gynaecology specialist working in Kuching.
Reference:
- ThorneSA, Nelson-Piercy. Risks of contraception and pregnancy in heat disease. Heart 2006; 922:1520-525.
- Nelson Piercy C. handbook of obstetric medicine. Informa healthcare 2010; 4:19-39
- Sarris I, Bewley S. Training in obstetrics and gynaecology, the essential curriculum. Oxford 2009;148-156
- David ML, Philip NB. An evidence based text for MRCOG. Hodder Arnold 2010; 2:59-64
[This article belongs to The Malaysian Medical Gazette. Any republication (online or offline) without written permission from The Malaysian Medical Gazette is prohibited.]