Pregnancy places extra demands on a woman’s heart. During the first trimester of pregnancy a woman’s blood volume increases by 40 to 50 percent. This volume then remains high for the remaining two trimesters. The amount of blood the heart pumps out each minute increases by 30 to 50 percent. Heart rate also increases by 10 to 15 beats per minute.
All this hard work is necessary so that the heart can supply blood and nutrients to the placenta, uterus and growing fetus. Even for a woman with a healthy heart, this can place serious demands on the heart.
Because having a baby has a profound effect on a woman’s cardiovascular system, some women with healthy heart develop problems while they are pregnant. The risk increases in women who are obese, those experiencing a pregnancy after 35, have diabetes or high blood pressure. Although there is no standard screening for those at risk, heart disease testing should be introduced for women at particularly high risk.
However, for those who already have a diagnosed heart condition such as a congenital heart disease (CAD) or a heart valve disorder, pregnancy can pose a serious health risk.
Cardiac Abnormalities in Pregnancy
Some women develop heart murmurs in pregnancy which they have never had before. A murmur is an unusual whooshing or swishing sound which the heart makes as it pumps blood. It produces no symptoms and a doctor can only hear it through a stethoscope. Most murmurs are harmless and require no treatment. However your doctor will want to determine the cause in case the heart valves are not working properly. Sometimes abnormal heart murmurs can be associated with heart valve disease.
Nearly 50 percent of women develop abnormal heartbeat called heart arrhythmias during pregnancy. The vast majority cause no symptoms and are only discovered when the doctor takes a patient’s pulse. Occasionally they can cause dizziness, lightheadedness or palpitations. In such instances an electrocardiogram (ECG) or 24 hour Holter monitor may be recommended so that the heart rhythm can be assessed. The patient is unlikely to require treatment although the heartbeat will be monitored. If symptoms continue or worsen, arrhythmia treatment such as antiarrhythmic medication may be considered.
A heart palpitation is a sensation or awareness of your own heartbeat or having a forceful or rapid heartbeat. They are very common in pregnant women due to hormonal changes in the body. Most palpitations are completely harmless and no cause for concern. In some cases however, they may be an indication of anemia in pregnancy or arrhythmia.
High Blood Pressure
There are different types of high blood pressure which can occur in pregnancy. A woman can enter pregnancy with an existing history of high blood pressure (known as chronic hypertension) or she can develop it during pregnancy (gestational hypertension). If gestational hypertension lasts after childbirth but clears up within 12 weeks the diagnosis is changed to transient hypertension.
Finally she may develop a sudden out of the blue rise in blood pressure which is a sign of a more serious pregnancy complication called preeclampsia. If your blood pressure becomes dangerously high (higher than 160/100 mm Hg) while pregnant, your doctor may prescribe blood pressure medications.
Stroke During Pregnancy
The overall risk of stroke increases 2.5-fold during and after pregnancy. About 90 percent of all pregnancy related strokes happen either during delivery or within 6 weeks of childbirth. Up to 45 percent of instances are caused by preeclampsia or eclampsia. One study found that the risk of ischaemic stroke was 8.7 times higher in the first 6 weeks after childbirth. The risk of hemorrhagic stroke was 2 to 3 times higher than normal during pregnancy but 28 times higher in the 6 weeks following childbirth. Overall however, the risk of pregnancy related stroke remains low.
This is a rare condition which causes heart failure in the last month of delivery or within 5 months of childbirth. The cause remains unknown. Although the heart can return to normal, it is associated with increased risk of complications during any subsequent pregnancy.
Can I get pregnant if I have pre-existing heart disease ?
If you do have a pre-existing heart condition and plan on having children you will need to have a pre-pregnancy consultation with a cardiologist (a doctor who specializes in treating heart problems).
Your pregnancy team will need to coordinate with the cardiologist on a regular basis and you will need frequent monitoring throughout the pregnancy. Some conditions may even require a coordinated approach between an obstetrician, cardiologist, anesthesiologist and paediatrician. Special arrangements may need to be made for labour and delivery. Fortunately today, with good prenatal care and management, many women with different types of cardiovascular disease are delivering healthy babies safely. Yet some types of heart problems continue to remain at very high risk and pregnancy is still not recommended. These include severe congestive heart failure, pulmonary hypertension (abnormally high blood pressure) and Eisenmenger’s syndrome (which causes low levels of oxygen to the organs).
Management Of Heart Disease While Pregnant
If you plan your pregnancy carefully as well as consulting both your cardiologist and gynaecologist, you should be able to have a safe 9 months. First your doctor will want to carry out a full physical examination including some diagnostic tests such as an echocardiogram to assess the overall condition of your heart. He will also discuss the potential problems and tell you what symptoms you need to watch out for which could indicate an issue. You may also need to discuss your heart medications because some drugs (even over the counter medications) may not be safe to continue. You could be prescribed different drugs or recommended a safer dosage. You will need more frequent prenatal visits than women without heart conditions, so you should factor this into your overall schedule.
|Last reviewed||:||16 January 2015|
|Writer/Translator||:||Dr. Ainol Shareha bt. Sahar|
|Accreditor||:||Dato’ Dr. Abdul Hadi b. Jaafar|