Atrial Fibrillation

Atrial fibrillation is the most common form of arrhythmia characterized by abnormally rapid heart rate.

It increases the risk of stroke and heart failure.

Abnormal electrical activity in the atria reduces the blood pumped into the ventricle, causing rapid heartbeat.

It causes

• palpitations,
• shortness of breath,
• weakness.

Atrial fibrillation is diagnosed based on physical examination, ECG, or Holter monitor.

Treatment helps to correct the abnormal rhythm of heart and to control the underlying condition that causes fibrillation.

Atrial fibrillation is not a serious condition but may lead to complications that are potentially life-threatening. 

Atrial fibrillation may remain asymptomatic in many people and is often diagnosed during physical examination.

When present, symptoms include

• Palpitations
• Weakness
• Inability to do strenuous physical activity
• Fatigue
• Lightheadedness
• Dizziness
• Confusion
• Shortness of breath
• Chest pain

Atrial fibrillation may be occasional in which the symptoms may come and go. The symptoms may last for few minutes to hours. Symptoms of persistent atrial fibrillation remain and do not resolve on its own.

Medications are often required to restore the normal rhythm of the heart.

Long-lasting persistent atrial fibrillation lasts for more than a year, while in permanent atrial fibrillation the normal rhythm cannot be restored.

Abnormal electrical discharges in the heart causes atrial fibrillation.

In some cases, there may be over 350 discharges per minute, causing abnormal contractions of the atria. This rapid, abnormal contractions reduce the ability of the chamber to pump blood into the ventricles.

The irregular electrical discharges are then passed on to the ventricle which starts contracting rapidly and irregularly. Thus, ventricles contract even before filling with blood, decreasing the amount of blood pumped into the blood vessels.

When a normal heart beats at a rate of 60 to 100 beats in a minute, in atrial fibrillation it ranges from 100 to 175.

Some of the possible causes of atrial fibrillation include

• Hypertension
• Coronary heart disease
• Heart attack
• Abnormality in heart valves
• Congenital heart diseases
• Metabolic disturbance
• Stimulants like caffeine, tobacco, or alcohol
• Improper functioning of the sinus node
• Lung diseases
• Previous heart surgery
• Viral infections
• Pneumonia or other diseases
• Surgery
• Sleep apnea

In lone atrial fibrillation, the cause of the condition is not known. Risk factors for atrial fibrillation are

• heart diseases,
• high blood pressure,
• chronic diseases,
• alcohol abuse,
• obesity,
• family history.

The risk of atrial fibrillation increases with age.

Review of medical history and signs and symptoms, and physical examination help in diagnosis of atrial fibrillation.

• ECG is the primary diagnostic tool for atrial fibrillation. It measures the conduction of electrical signals in the heart.

• Holter monitor is a device that records the heart rhythm for more than 24 hours.

• Event recorder is used to monitor the electrical activity of the heart for few weeks to months. The monitor can be activated when there is an abnormal activity to obtain an ECG recording of the preceding few minutes.

• Echocardiogram enables to detect structural diseases of the heart by producing video images of the functioning of heart. Transesophageal echocardiography is another form of echocardiogram where a flexible tube with a transducer is inserted into the esophagus to obtain visuals of the heart.

• Blood tests are recommended to rule out other causes like thyroid diseases

• Stress test measures the heart activity while exercising

• Chest x-ray is ideal to visualize the lungs and heart. It is often used to diagnose other conditions that produce similar symptoms.

Treatment is based on the duration of the condition, intensity of symptoms, and the underlying cause of atrial fibrillation. 

Treatment strategies restore the rhythm of heart and also control the formation of blood clot.

Factors like presence of other medical conditions and overall health of the patient also influence the kind of treatment. Treating the underlying condition like thyroid disorder helps to control the symptoms of atrial fibrillation.

The rhythm of heart can be restored to normal through cardioversion.

Cardioversion is done through electrical method or by using medications. In electrical cardioversion, an electrical shock is delivered to the heart which stops the discharges for a short duration. When the heart regains function, it usually restores the default normal rhythm in most of the people. This procedure is usually done under sedation.

Anti-arrhythmic medications are used to restore the normal heart rhythm. These medications may be administered orally or intravenously, usually with continuous monitoring of heartbeat. Once the heart rhythm is back to normal, similar medications are prescribed to prevent recurrence of fibrillation.

Blood thinning drugs like warfarin are usually given for two or more weeks before cardioversion to prevent chances of blood clots. Some common antiarrhythmic medications commonly used to prevent recurrence of fibrillation include 

• Dofetilide
• Flecainide
• Propafenone
• Amiodarone
• Sotalol

Medications are also used to control the heartrate. Digoxin, calcium channel blockers, and beta blockers are often prescribed to restore the heart rhythm. Anticoagulants are also recommended to reduce the risk of blood clots in people with atrial fibrillation.

Catheter and surgical procedures are recommended when medications and cardioversion are not helpful in restoring the normal heart rhythm.

Catheter ablation

In this procedure the hotspots in the heart that produces rapid, abnormal electrical discharges, are removed using radiofrequency, heat, or cryotherapy. In catheter ablation, a catheter is inserted into the blood vessel and guided to the heart. Ablation of hotspots corrects the abnormal rhythm without use of medications or any devices.

Surgical maze procedure

In this open-heart surgical procedure, a surgeon produces a pattern of scar tissues in the atrial wall using radiofrequency or cryotherapy. These scar tissues inhibit or block the conduction of stray electrical signals that cause atrial fibrillation.

Atrioventricular node ablation

In this procedure, the electrical pathway from atrium to ventricle is destroyed. This prevents the passage of atrial signals to the lower chambers. To keep normal contractions of ventricle, a pacemaker is inserted. Blood thinning medications are continued to reduce the risk of blood clots.

Taking steps to reduce the risk of heart diseases help to prevent chances of atrial fibrillation.

This includes having

• a heart-healthy diet,
• quitting smoking,
• being physically active,
• maintaining a healthy body weight.

Those who have a higher risk of atrial fibrillation should try to keep cholesterol and triglycerides at healthy levels.

Limiting alcohol consumption, and controlling blood sugar levels are also important. 

A few alternative and homeopathic remedies exist for Atrial fibrillation.

Practicing yoga is considered to be good for improving

• quality of life,
• reducing depression,
• preventing anxiety.

Relaxing breath exercises are being tried to reduce the effect of stress on heart.

Protein-rich diet with good amount of magnesium and potassium are supposed to be good in controlling arrhythmia.

Specific supplements are also an option for controlling symptoms of atrial fibrillation. 

Lifestyle changes are important in improving heart health and coping with Atrial fibrillation.

• Regular exercise,
• having heart-healthy food,
• not smoking,
• maintaining a healthy body weight,
• keeping cholesterol levels under check

help in controlling symptoms of this condition.

While living with this condition, ensure to keep all medical appointments and do carry the medication list. Be consistent with medications as prescribed.

Be cautious about nutritional supplements, over-the-counter medications, and normal allergy medications as they may have drug interactions.

Talk to your doctor about the side effects of medications.

Join a support group to discuss and exchange experiences of coping with the condition. 

There are several risks and complications associated with Atrial fibrillation.

Atrial fibrillation may lead to stroke and heart failure.

Risk of stroke increases with age and other conditions like hypertension and diabetes.