Cardiac Diseases & Pregnancy
Certain cardiac diseases carry a very low risk to the mother and the fetus. These include mitral regurgitation, aortic regurgitation, hypertrophic cardiomyopathy, mitral valve prolapse, and intracardiac shunts such as atrial septal defects and ventricular septal defects. Mitral valve prolapse is often well tolerated during pregnancy and the prolapse may actually decrease because of the normal changes that the heart goes through during pregnancy.
Women with pulmonic valve disease and tricuspid valve disease may also have relatively uncomplicated pregnancies. However, other types of valve disorders may present problems with pregnancy. For example, there is an increased risk when the mother has mitral or aortic stenosis. Often these valve disorders are the result of rheumatic heart disease. These patients may require close observation, medications and specialized monitoring during labor and delivery.
Amongst the highest at-risk populations for developing complications during pregnancy are women who have pulmonary hypertension (elevated lung pressures) either due to congenital heart disease or due to an independent entity. Women who continue to have cyanosis (low blood oxygen) despite surgery are at high-risk for maternal complications, premature and small babies, and death during pregnancy. Women with poor cardiac function prior to the pregnancy are often unable to withstand the increased circulation of pregnancy and develop symptoms. Women with cardiac symptoms at rest are also among the highest at-risk populations for developing complications as pregnancy progresses.
Arrhythmias (irregular heart rhythms) may occur for the first time or occur with increased frequency during pregnancy. In women with structurally normal hearts, these arrhythmias usually do not pose a significant risk. However, the cause of the arrhythmia should be sought and treated appropriately. For women that develop atrial fibrillation, it is important to look for the underlying heart problem causing the atrial fibrillation. Atrial fibrillation is usually associated with valvular heart disease, hyperthyroidism, pulmonary embolism or hypertension.
Other pre-existing cardiac problems, including coronary artery disease and women with pacemakers or defibrillators, have been managed by the Heart Disease and Pregnancy Program. Cardiac problems may arise during pregnancy in women who have had no history of cardiac problems. For example, heart failure (fluid overload) may occur because the increased volume of pregnancy is not tolerated. These women may have developed heart failure due to an underlying valvular disease, arrhythmia, and/or cardiomyopathy. A small number of women will develop a cardiomyopathy, a specific weakening of the heart muscle that appears to be caused by the pregnancy. This form of cardiomyopathy may occur at either the end of pregnancy or several months after delivery. It is not clear why this happens and women may not have a complete recovery and/or the cardiomyopathy may reoccur with future pregnancies. Therefore, future childbearing would be contraindicated.
Although quite rare, women may present with a myocardial infarction (heart attack) during pregnancy. These women need to be assessed and treated as if they are not pregnant. Although certain drug choices can be made to decrease the risk to the fetus, management strategies are similar to the non-pregnant state, though certain precautions may be advised.
A successful pregnancy for women with heart disease requires specialized care, preconception evaluation, continuation of select medications and close observation during the pregnancy.
Heart Disease and Pregnancy Program
1-866-662-8467 (toll free)