Atrial Fibrillation: Heart Symptoms, Diagnosis, & AFib Treatment

The AFib definition is an irregular heartbeat that may lead to blood clots, heart failure, stroke, or other complications.

What Is Atrial Fibrillation?

What is AFib? Atrial fibrillation (AFib) is a heart rhythm abnormality caused by a problem with your heart's electrical system. Normally, your heart's electricity flows from the top chambers (atria) to the bottom chambers (ventricles), causing a normal contraction. In atrial fibrillation, the electrical flow is chaotic, causing the heartbeat to become irregular and rapid.

AFib signs and symptoms include an irregular heart rate and a feeling of fluttering.

Warning Sign: Uneven Pulse

Atrial fibrillation causes an irregular heart rate. If you check your pulse, you may feel a "fluttering" sensation. When atrial fibrillation is new in onset or poorly controlled by medications, you will often feel your heart racing. This rapid, abnormal heart rate can be dangerous if not treated and controlled quickly. With AFib, heart rate is so fast and irregular, blood may not be pumped adequately throughout your body.

Heart rate in AFib is rapid and irregular.

AFib vs. Normal Heart Rhythm

When your heart beats with a normal rhythm, electricity flows from the top of your heart to the bottom of your heart, causing your heart muscle to contract and moving your blood through your body. In AFib, the electricity flows chaotically and the bottom chambers of your heart contract irregularly. One of the hallmark AFib symptoms is this so-called fluttering or fibrillation.

Dizziness is one of the potential signs of AFib.

Warning Sign: Dizziness

If your heart goes into atrial fibrillation, you may experience dangerous and frightening symptoms. AFib may cause symptoms such as:

  • Dizziness
  • Feeling of palpitations
  • Shortness of breath
  • Chest pain
  • Fatigue or exercise intolerance
AFib of the heart may increase the risk of stroke.

AFib and Stroke

Atrial fibrillation is a risk factor for stroke. About 15 percent of all people who have strokes have AFib. Because of the irregular and chaotic flow of blood through the heart, small blood clots can form in the heart chambers when you have atrial fibrillation. These clots can travel through the bloodstream to the brain, causing a stroke. This is why people with chronic AFib are commonly on blood-thinning medications.

Follow your doctor’s instructions for how to treat AFib but call 911 if you have a medical emergency.

When To Call 911

If you think you are experiencing atrial fibrillation and have chest pain, feel faint, feel a very rapid heart rate (greater than 100 beats per minute), or have any signs or symptoms of a stroke, call 911 immediately or have someone call 911 for you.

High blood pressure is one of the potential causes of AFib.

What Causes Atrial Fibrillation?

Atrial fibrillation is a common problem. What causes AFib? Risk factors for AFib include:

Some AFib causes and risk factors are not controllable.

Risk Factors You Can't Control

Having a family history of atrial fibrillation is a strong risk factor for you developing it as well. Your risk of getting AFib also increases with age. White males have a higher incidence of atrial fibrillation overall.

AFib and alcohol do not mix, but you can refrain from drinking and smoking which are bad for your heart.

Risk Factors You Can Control

There are some risk factors for atrial fibrillation that are in your control. Maintain a healthy lifestyle and watch your weight. Stop smoking and limit alcohol use. Do not use illegal drugs and be very careful if you use certain prescription drugs such as albuterol or other stimulants. Talk to your doctor if you are prescribed these medications and have concerns.

Heart surgery may trigger AFib in some people.

Heart Surgery Can Be a Trigger

One of the risks of having open-heart surgery or coronary artery bypass graft surgery (CABG) is atrial fibrillation. Your doctor will work to control or correct this arrythmia as it can lead to other complications.

When it comes to the heart, AFib without an obvious cause is called lone AFib.

Lone AFib

Atrial fibrillation that happens in younger people (under 60 years old), without an obvious cause is called lone AFib. Lone AFib can be triggered by exercise, eating, sleeping, and alcohol. Sometimes it comes and goes on its own and may not need immediate treatment. Consult your doctor.

AFib ECG tracing will show the doctor what your heart is doing.

Diagnosing AFib: EKG

Do you wonder how to diagnose AFib? Your doctor will diagnose atrial fibrillation on an electrocardiogram (EKG) machine. This heart tracing shows a distinct pattern in the electricity of the heart that your doctor can diagnose. If your AFib comes and goes, you may need to wear a continuous heart monitor (Holter monitor) to diagnose the abnormal rhythm. In addition, some heart monitors may be purchased over-the-counter for about 50 - 100 dollars.

Doctors use a variety of tests to diagnose AFib.

Other Tests for AFib

How is AFib diagnosed? Once atrial fibrillation is confirmed or suspected your doctor will perform further tests to check your heart muscle and heart valves and to screen for blood clots. These tests include an echocardiogram (ultrasound of the heart) or a stress test or possibly even a catheterization to check the blood vessels for blockage.

AFib paroxysmal is AFib that is intermittent.

The Course of AFib

Do you wonder how to diagnose AFib? Your doctor will diagnose atrial fibrillation on an electrocardiogram (EKG) machine. This heart tracing shows a distinct pattern in the electricity of the heart that your doctor can diagnose. If your AFib comes and goes, you may need to wear a continuous heart monitor (Holter monitor) to diagnose the abnormal rhythm. In addition, some heart monitors may be purchased over-the-counter for about 50 - 100 dollars.

Cardioversion for AFib may help restore your heart to a normal rhythm.

Treatment: Cardioversion

In some cases, atrial fibrillation can be corrected with an electric shock to the heart called a cardioversion. In severe emergency cases, this may be the only choice to control AFib. Medications may also be tried to do the cardioversion of your heart rhythm. If your AFib has been going on for more than 48 hours, you may not be a candidate for cardioversion as your risk of having blood clots that could lead to stroke is increased.

There are several different types of AFib medications that are available.

Treatment: Medication

Patients with atrial fibrillation are usually prescribed a combination of medicines to prevent complications. AFib medicine may include blood thinners or anti-clotting medications to help prevent the risk of stroke. Medications that control the rate that your heart beats keep the heart from beating too fast. Some medications are specifically designed to control the electrical rhythm of the heart, keeping it from becoming more irregular and chaotic.

Ablation for AFib involves the destruction of tissue that is responsible for the arrhythmia.

Treatment: Ablation

In certain instances, medications or cardioversion may not control your atrial fibrillation effectively. A specially trained cardiologist (called an electrophysiologist) may perform a surgical procedure called an ablation to fix your atrial fibrillation. A radiofrequency ablation is done through a catheter threaded into your heart to send low-voltage, high-frequency electricity into the area of your heart that is causing the irregular electrical rhythm. This destroys the small amount of tissue causing the abnormal heart beat and may totally cure the AFib.

AFib surgery is a kind of AFib treatment that may help conduction of electricity through the heart be more regular.

Treatment: Surgery

In some cases, surgery on your heart may be needed to treat your AFib. The Maze procedure is a type of surgery where small cuts are placed in the upper chamber of the heart (atria) to help the conduction of electricity to be regular. This procedure may also be done through small incisions or catheters threaded into the heart.

Pacemakers for AFib treatment are implanted if a patient suffers from a heart rate that is too slow.

Treatment: Pacemaker

In rare instances, after an ablation to treat your atrial fibrillation, your doctor may need to implant a pacemaker. Pacemakers themselves are not designed to treat atrial fibrillation. They are mainly used to correct slow heartbeats. Pacemakers for AFib may be placed if the patient suffers from slow heart rate (bradycardia) that causes symptoms. Discuss the possible outcomes of your heart treatment with your cardiologist.

Drugs for AFib may cause complications, so ask your doctor if your condition limits your lifestyle.

Outlook for AFib

If your atrial fibrillation is well controlled, or corrected with a heart procedure, you may not have any life-changing symptoms from your AFib. Some people with chronic AFib need to be maintained on medications and blood thinners for the rest of their lives. The side effects of these medications can cause long-term complications. Discuss your medications with your cardiologist to see what limitations they may cause on your lifestyle.

Living a healthy lifestyle may help keep symptoms for AFib at bay.

Preventing AFib

Keeping yourself healthy and changing bad lifestyle habits is an important way to lower your risk for atrial fibrillation. Exercise regularly, quit smoking, keep your blood pressure under control, and eat a nutritious diet that is low in fat and salt to lower your risks of heart problems.

Check your pulse at least once per month to help identify AFib and other potential heart problems.

Check Your Pulse Regularly

The National Stroke Association suggests everyone over the age of 40 checks their pulse once every month. There is an initiative called "Check Your Pulse" aimed at identifying abnormal heart rates and patients with undiagnosed atrial fibrillation early.

What does AFib feel like? It may feel like skipped heart beats, a thud, or a racing heart. You may feel heart racing. See your doctor if you experience these symptoms. The doctor can tell whether you suffer from atrial flutter vs AFib, signs and symptoms of AFib, AFib with RVR (rapid ventricular response), or some other cardiac condition altogether. (RVR with AFib means that the lower chambers of the heart, the ventricles, beat too fast due to AFib.)



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  • American Family Physician: "Diagnosis and Treatment of Atrial Fibrillation."
  • American Heart Association: "High Blood Pressure, AFib, and Your Risk of Stroke," "Prevention Strategies for Atrial Fibrillation (AFib or AF)," "Understand Your Risk for Arrhythmia," "What Are the Symptoms of Atrial Fibrillation (AFib or AF)?" "What Is Atrial Fibrillation (AFib or AF)?" "Who Is at Risk for Atrial Fibrillation (AF or AFib)?" "Why Atrial Fibrillation (AF or AFib) Matters."
  • Atrial Fibrillation Association: "Know Your Pulse."
  • National Stroke Association: "Controllable Risk Factors -- Atrial Fibrillation"
  • "How to Know It's Atrial Fibrillation."
  • "Pulse Check."
  • UpToDate: "Epidemiology and Risk Factors for Atrial Fibrillation," "Mechanisms of Atrial Fibrillation," "Overview of Atrial Fibrillation," "Patient information: Radiofrequency catheter ablation for the heart (Beyond the Basics)," "Paroxysmal Atrial Fibrillation," "The Role of Pacemakers in the Prevention of Atrial Fibrillation," "Surgical Approaches to Prevent Recurrent Atrial Fibrillation"
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