Cardiac Arrhythmia During Pregnancy

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Your heart beats due to a series of electrical impulses that stimulate the cardiac muscles to contract in a regular, sequential pattern. An arrhythmia is any change in the normal conduction of the electrical impulses that changes the normal heartbeat. The heart may beat too fast, too slow, or erratically, depending on what is causing the arrhythmia.

When the heart doesn’t beat normally, it can’t pump blood effectively. When the blood doesn’t move effectively, the rest of the body’s organs can’t get the oxygen and nutrients they need.

Types of arrhythmias

There are several common types of arrythmias:

  • Atrial fibrillation (irregular contraction of the upper chambers of the heart)
  • Bradycardia (slow heart rate; usually less than 60 beats per minute)
  • Tachycardia (fast heart rate; usually more than 100 beats per minute)
  • Ventricular fibrillation (disorganized or irregular contraction of the lower chambers of the heart)

Pregnancy and your heart

During pregnancy, your heart works harder than normal. The amount of blood in your body increases and about 20% of this blood will be flowing to your uterus. Since this is extra work for your heart, your heartbeat will increase by about 10 to 20 beats per minute as your pregnancy progresses. Additionally, starting in your second trimester, your blood vessels start to widen to let more blood flow through them, and this can lead to decreased blood pressure.

Because of these changes to your body and your heart, you may notice faster-than-normal heartbeats or even feel lightheaded or short of breath. If these symptoms occur infrequently or as the result of over-exertion or stress, it is likely nothing serious. However, if you notice these symptoms frequently or at rest, they may indicate an arrhythmia or another heart abnormality.

Treatment of arrhythmias

If you or your doctor suspect that you are experiencing an arrhythmia, you will undergo diagnostic testing, possibly including a 24-hour Holter monitor or an electrocardiogram, to rule out other causes of your symptoms and identify what type, if any, of arrythmia is occurring.

The treatment options for arrhythmias during pregnancy are somewhat limited, since many anti-arrhythmic drugs are not safe for all stages of pregnancy. Electric cardioversion, in which a small amount of energy is applied to the heart to stimulate a return to normal rhythm, and catheter ablation, in which the part of the heart that originates the arrhythmia is destroyed, may be considered in cases of persistent, severe arrhythmias, but experience with these techniques in pregnant patients is very limited.

Cardiac risk factors

If you have been diagnosed with any heart condition prior to pregnancy, you may be at risk for developing an arrhythmia. Talk to your doctor before you conceive, or as soon as you find out you’re pregnant, to learn about risks related to your pregnancy. Depending on your individual health status, you may need to manage your condition differently if you want to get pregnant. During your pregnancy, you will likely undergo increased monitoring and you may need to change treatments you are currently using to manage your arrhythmia. (Do not start or stop any treatment without speaking to your doctor.)

Stay heart healthy and heart wise

Call your doctor if you have any of the following symptoms of arrhythmia:

  • Heart palpitations, rapid heartbeats, or fluttery or pounding sensation in your chest
  • Extreme fatigue
  • Dizziness or lightheadedness
  • Fainting
  • Shortness of breath
  • Chest pain

Do your best to manage stress and anxiety and get plenty of rest. Keep your heart healthy by engaging in regular physical activity and eating a balanced diet. Share any unusual or unexplained symptoms with your doctor.

Jennifer Gibson
Dr. Jennifer Gibson earned a Bachelor of Science degree in Biochemistry from Clemson University and a Doctor of Pharmacy degree from the Medical College of Virginia School of Pharmacy at Virginia Commonwealth University. She trained as a hospital pharmacist and is the author of clinical textbooks, peer-reviewed journal articles, and continuing education programs for the medical community, as well as a contributor to award-winning healthcare blogs and websites. In her free time, she enjoys running, reading, traveling, and spending time with her family.

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