A fast, pounding heartbeat could be due to AFib, a type of heart rhythm disorder. Know the warning signs and when treatment is needed.
Update Date: 03.10.2025
Atrial fibrillation (AFib) is an irregular and often very rapid heart rhythm. An irregular heart rhythm is called an arrhythmia. AFib can lead to blood clots in the heart. The condition also increases the risk of stroke, heart failure and other heart-related complications.
During atrial fibrillation, the heart's upper chambers, called the atria, beat chaotically and irregularly. They beat out of sync with the lower heart chambers, called the ventricles. AFib may cause a fast, pounding heartbeat, shortness of breath or light-headedness. Some people don't notice symptoms.
Episodes of atrial fibrillation may come and go, or they may be constant. AFib itself usually isn't life-threatening. But it's a serious condition that needs proper treatment to prevent stroke.
Treatment for AFib may include medicines, therapy to shock the heart back to a regular rhythm and procedures to block faulty heart signals.
A person with atrial fibrillation also may have a related heart rhythm disorder called atrial flutter. The treatments for AFib and atrial flutter are similar.
Symptoms of atrial fibrillation (AFib) may include:
Some people with AFib don't notice any symptoms.
Atrial fibrillation may be:
If you have symptoms of atrial fibrillation, make an appointment for a health checkup. You may be referred to a doctor trained in heart diseases, called a cardiologist.
If you have chest pain, get emergency medical help right away. Chest pain could mean that you're having a heart attack.
To understand the causes of atrial fibrillation (AFib), it may be helpful to know how the heart typically beats.
The heart has four chambers:
Inside the upper right heart chamber is a group of cells called the sinus node. The sinus node makes the signals that start each heartbeat.
The signals move across the upper heart chambers. Next, the signals arrive at a group of cells called the AV node, where they usually slow down. The signals then go to the lower heart chambers.
In a healthy heart, this signaling process usually goes smoothly. The resting heart rate is typically 60 to 100 beats a minute.
But in atrial fibrillation, the signals in the upper chambers of the heart are chaotic. As a result, the upper chambers tremble or shake. The AV node is flooded with signals trying to get through to the lower heart chambers. This causes a fast and irregular heart rhythm.
In people with AFib, the heart rate may range from 100 to 175 beats a minute.
Changes with the heart's structure are the most common cause of atrial fibrillation (AFib).
Heart diseases and health conditions that can cause AFib include:
Heart surgery or stress due to surgery or sickness also may cause AFib. Some people who have atrial fibrillation have no known heart disease or heart damage.
Lifestyle habits that can send the heart into AFib may include:
Things that can increase the risk of atrial fibrillation (AFib) include:
A possible complication of atrial fibrillation (AFib) is blood clots. Blood clots can lead to stroke.
The risk of stroke from AFib increases as you grow older. Other health conditions also may increase the risk of a stroke due to AFib. These conditions include:
Blood thinners are commonly used to prevent blood clots and strokes in people with atrial fibrillation.
Healthy lifestyle choices can reduce the risk of heart disease and may prevent atrial fibrillation (AFib). Here are some basic heart-healthy tips:
Atrial fibrillation (AFib) may be diagnosed when a health checkup is done for another reason.
To diagnose AFib, the healthcare professional examines you and listens to your heart. You are usually asked questions about your medical history and symptoms. Tests may be done to look for conditions that can cause changes in the heartbeat, such as heart disease or thyroid disease.
Tests to diagnose atrial fibrillation (AFib) may include:
The goals of atrial fibrillation (AFib) treatment are to:
Treatment depends on:
Treatment may include:
Together, you and your healthcare team talk about the best treatment option for you. It's important to follow your atrial fibrillation treatment plan. If AFib isn't well controlled, it may lead to complications, including stroke and heart failure.
Treatment for atrial fibrillation (AFib) may include medicines to do the following:
Medicines may include:
If atrial fibrillation symptoms are bothersome or if this is the first AFib episode, a treatment called cardioversion may be done to reset the heart rhythm.
Cardioversion can be done in two ways:
Cardioversion is usually done in a hospital as a scheduled treatment. But it may be done in emergency situations. If it's scheduled, you may be told to take a blood thinner such as warfarin (Jantoven) for a few weeks before the treatment. The medicine reduces the risk of blood clots and strokes.
After electrical cardioversion, medicines to control the heart rhythm may be needed for life to prevent AFib from returning. Even with medicine, AFib could come back.
If AFib doesn't get better with medicine or other treatments, a procedure called cardiac ablation may be necessary. Sometimes ablation is the first treatment.
Cardiac ablation often uses heat or cold energy to create tiny scars in the heart. Heart signals can't pass through the scars. So the treatment can block faulty heart signals that cause AFib. During cardiac ablation, a doctor places a flexible tube called a catheter through a blood vessel, usually in the groin. The doctor guides the tube to the heart. More than one catheter may be used. Sensors on the tip of the catheter apply the cold or heat energy.
Less commonly, ablation is done using a scalpel during open-heart surgery.
There are several types of cardiac ablation. The type used to treat atrial fibrillation depends on your specific symptoms, overall health and whether you're having another heart surgery.
Maze procedure. A doctor uses heat or cold energy or a scalpel to create a pattern of scar tissue in the upper chambers of the heart. The pattern is called a maze. The heart's electrical signals can't pass through scar tissue. So the maze blocks the stray heart signals that cause atrial fibrillation.
If a scalpel is used to create the maze pattern, open-heart surgery is needed. This is called the surgical maze procedure. It's the preferred AFib treatment for those who need another heart surgery. For example, it may be done during coronary artery bypass graft surgery or heart valve repair.
Atrial fibrillation may return after cardiac ablation. If this happens, another ablation or heart treatment may be recommended. After cardiac ablation, blood thinners may be needed for life to prevent strokes.
If you have AFib but can't take blood thinners, a doctor may close a small sac in the left upper heart chamber. This sac is called an appendage. It's where most AFib-related clots form. This procedure is called left atrial appendage closure.
During left atrial appendage closure, a doctor gently guides a closure device through a catheter to the sac. Once the device is in place, the catheter is taken out. The device stays in permanently. This procedure also is an option for some people with AFib who are having another heart surgery.
A healthy lifestyle can help prevent or treat conditions that can lead to atrial fibrillation (AFib). Try the following steps to improve your heart health:
It also is important to have regular health checkups. Tell your healthcare team if your AFib symptoms get worse.
If you have an irregular or pounding heartbeat, make an appointment for a health checkup. If AFib is found early, treatment may be easier, and it may work better. You may be sent to a doctor trained in heart diseases. This type of doctor is called a cardiologist.
Here's some information to help you get ready for your appointment.
For atrial fibrillation, some basic questions to ask your doctor include:
Don't hesitate to ask any other questions during your appointment.
During a health checkup, you are usually asked many questions. Being ready to answer them may save time to go over any details you want to spend more time on. You may be asked:
It's never too early to make heart-healthy lifestyle changes. Eat healthy foods, stay active and don't smoke.
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