Premature Atrial Contractions

What are premature atrial contractions?

Premature atrial contractions (PACs) are extra heartbeats that start in the upper chambers (or atria) of your heart.

Normally, your heart contracts in an organized manner. Electrical impulses (which tell your heart cells to contract) start in the right upper corner of the right atrium in a region called the sinus node. The sinus node fires electrical impulses in an organized and rhythmic manner, determining your heart rate. PACs occur when your upper chambers contract prematurely from an area different from the sinus node and briefly interrupt your heart’s normal rhythm.

When the premature, or early, signal tells your heart to contract, there may not be much blood in your heart at that moment. That means there’s not much blood to pump out. A pause and a strong beat may follow the extra heartbeat, making it feel like a skipped beat.

A premature atrial contraction can feel like an extra beat when there’s more blood in the heart to pump than there is with a skipped beat.

Premature atrial contractions, also called beats or complexes, are common in people of all ages. A premature atrial contraction can make you feel unsettled. But you usually don’t need to be concerned unless you have a lot of them.

What are the symptoms of premature atrial contractions?

Premature atrial contraction symptoms may include heartbeats that:

• Are pounding or feeling stronger than your regular heartbeats
• Skip
• Feel faster and out of rhythm from your regular heart rate (palpitations)

You may also have anxiety or shortness of breath. But you may not have any symptoms at all.

What causes premature atrial contractions?

Premature atrial contraction causes may include:

• A change in the amount of blood going to your heart
• Injury to your heart
• A problem with your heart’s structure (like coronary artery disease or hypertrophic cardiomyopathy)
• An issue with the amount of electrolytes or minerals (like potassium or magnesium) in your body
• Tiredness
• Caffeine intake
• Intake of beverages containing alcohol
• Tobacco product use
• Stress
• Certain medications, including some used for heart issues or mental health
• Recreational drug use
• Thyroid problems

If PACs happen to you often, your healthcare provider will look for a cause. Often, the cause is unknown.

What are the risk factors for premature atrial contractions?

Anyone can get premature atrial contractions, but they’re more likely to happen frequently in people who:

• Are taller
• Are pregnant
• Have cardiovascular disease
• Aren’t physically active
• Have low HDL cholesterol
• Have a higher systolic blood pressure
• Have diabetes
• Have COPD or other pulmonary diseases
• Don’t drink enough water
• Smoke
• Take in excessive caffeine or stimulants
• Don’t get enough restful sleep
• Are very anxious or have high levels of stress
• Have electrolyte abnormalities
• Use recreational drugs

What are the complications of premature atrial contractions?

Frequent premature atrial contractions can lead to atrial fibrillation (Afib).

Researchers define “frequent” PACs by different numbers. They can range from 76 to more than 500 premature atrial contractions in 24 hours, for example.

How are premature atrial contractions diagnosed?

Usually, your blood pressure is normal with premature atrial contractions. It’s possible for a healthcare provider to miss premature atrial contractions during a physical exam. This is because they may not happen during the exam.

If you’re having premature atrial contractions, your provider may want to order:

• Electrocardiogram (EKG). If your heart rhythm reading is normal, you may not need any other test.
• Temporary heart monitor. This device that you wear checks your heart rhythm for a day or two or even up to two weeks.
• Echocardiogram. This ultrasound shows your heart’s structure.
• Blood tests. These check your electrolyte levels and thyroid hormone levels.

How are premature atrial contractions treated?

Most of the time, you don’t need treatment for PACs. They usually go away on their own. But if your symptoms are bad or happen regularly, your healthcare provider can treat the cause.

Your provider may treat your premature atrial contractions with:

• Medication; providers choose beta-blockers first, but sometimes, they prescribe antiarrhythmics
• Catheter ablation (rare)

Complications/side effects of treatment

Beta-blockers can make you feel tired, dizzy or nauseated. Talk to your provider if your side effects don’t get better.

Different antiarrhythmic medications (like flecainide, procainamide and amiodarone, among others) can have several side effects and interact with other medications.

Catheter ablation carries risks like blood clots, bleeding or infection. But providers generally consider it a low-risk procedure. Complications rarely happen after the procedure. You can most likely return to work in a week.

How can I lower my risk?

You may be able to lower your risk of premature atrial contractions by:

• Being physically active.
• Managing your blood pressure.
• Managing your cholesterol.
• Not using tobacco products.
• Getting enough sleep.
• Drinking less caffeine.
• Limiting your use of alcohol.
• Managing your stress.
• Not using addictive substances.

What can I expect if I have premature atrial contractions?

In most cases, you don’t need treatment and your outlook is good. But if you’re having premature atrial contractions often, you may be at risk of getting atrial flutter and atrial fibrillation (Afib).

Your outlook depends on what’s causing your premature atrial contractions. Your provider will look at the conditions you already have when considering your prognosis. For example, your situation is more serious if you have problems with your heart’s structure.

How do I take care of myself?

You may be able to have fewer premature atrial contractions if you:

• Get physical activity regularly.
• Reduce your intake of alcohol and caffeine.
• Stop using tobacco products.
• Avoid dehydration and lack of sleep.

When should I see my healthcare provider?

Usually, premature atrial contractions may go away by themselves and may recur during periods of stress or physical illness. Pay attention to whether you start having more PACs. You should make an appointment with a healthcare provider if your symptoms continue, get worse or happen with other symptoms.

What questions should I ask my healthcare provider?

You may want to consider asking your provider:

• Do you know what’s causing my premature atrial contractions?
• Do you recommend treatment for me?
• How often do I need check-ups?

Are premature atrial contractions the same as atrial fibrillation?

No. Atrial fibrillation is a more serious heart rhythm issue with an irregular heartbeat.

Should I be concerned about premature atrial contractions in pregnancy?

No. Premature atrial contractions in pregnancy are common. They normally stop by themselves and don’t need treatment.

What’s the difference between premature atrial contractions and premature ventricular contractions?

They start in different parts of your heart. Premature atrial contractions start in your atria (upper chambers). Premature ventricular contractions start in your ventricles (lower chambers).