Atrial fibrillation is the most common type of heart arrhythmia in which the heartbeat of a person becomes irregular and often very fast. This increases the chances of a stroke, heart failure or other hear-related problems. In this medical condition, the upper two chambers of the heart (the atria) are affected and thus, start to beat irregularly and often too rapidly. This disturbs the sync with the lower two chambers of the heart (the ventricles), thereby increasing risk of heart-related complications.
A person experiences atrial fibrillation might experience heart palpitations, shortness of breath and acute weakness. Even though, episodes of atrial fibrillation may come and go, in some cases, a person might develop a type of atrial fibrillation which refuses to settle down and hence, requires treatment. That said, the condition is not life-threatening but it is a serious medical condition, which may require emergency treatment in cases symptoms intensify.
Causes of Atrial Fibrillation
The irregular and often rapid heartbeat caused because of atrial fibrillation occurs when the upper two chambers of the heart get chaotic electrical signals. This disturbs their normal beating rhythm and causes erratic and fast heat rate. The heart rate for a person experiencing atrial fibrillation ranges between 100-175 beats a minute; however, the normal beat of a person is 60-100 per minute.
Technically, the heart is made of four chambers – the upper chambers known as atria and the lower chambers called the ventricles. In the upper chambers of the heart, there is a group of cells known as the sinus node, which are the natural pacemakers of the heart. These nodes produce signals which trigger the heartbeat. These signals are generated in the upper chambers and travel to the lower chambers through the connecting pathway known as the atrioventricular (AV) node. Normally, this movement of the signals causes the blood to flow through the heart and body. But in atrial fibrillation, this signals become chaotic and hence, they quiver which results in too many impulses to get through the ventricles. This in turn, causes the lower chambers also to beat rapidly, even though it is fairly lesser in intensity than the atria.
These changes to the normal functioning of the heart can be caused by a number of factors such as:
- High blood pressure
- Previous or present heart attack
- Coronary artery disease
- Abnormal heart valves
- Congenital heart defects or problems
- An overactive thyroid gland or other imbalances
- Certain medications
- Stimulants such as caffeine, tobacco or alcohol
- Lung problems
- Previous heart surgery
- Viral infections
- Improper functioning of the sinus node
- Stress caused due to surgery, or a critical medical condition
- Sleep apnea
Symptoms of Atrial Fibrillation
Some patients who have atrial fibrillation might not have symptoms and might know about the condition during a physical examination. However, for cases, where patients experience symptoms, these include:
- Palpitations in the heart
- Chest pain
- Acute weakness
- Inability or reduced ability to do physical exercise
- Shortness of breath
- Chest pain
That said, the symptoms may be occasional, persistent, long-standing persistent or permanent, depending on case-to-case.
Treatment of Atrial Fibrillation
For patients, who do not experience any symptoms, treatment for atrial fibrillation may not be required, unless symptoms start to develop. However, on the other hand, for those who experience atrial fibrillation symptoms, the following treatment options individually or in combination may be recommended depending on the condition of the patient.
Medications: These are advised to prevent clots and strokes, slow down the pacing heart rate and get the heart rhythm in control. Certain medications include blood thinners, heart rate drugs and heart rhythm correctors. These medications have side effects and also certain risk; their usage varies from case-to-case.
Surgical Procedures: For patients whose symptoms cannot be treated by medications, a surgical procedure to correct the dysfunctional electrical activity of the heart may be required. Two of the common procedures include:
- Electrical cardioversion: In this, the person’s heart is given shocks through paddles or stick patches (electrodes) to regulate the heartbeat.
- Cardiac ablation: This involves two types of procedures namely catheter ablation and surgical ablation. In the former, the surgeon inserts a thin, flexible tube into the blood vessel in the leg or neck and guides the same to the heart via X-ray images. Once placed in the position, this tube known as catheter sends out electrical signals to destroy the cells causing the irregular heartbeat. In case of surgical ablation, the doctor makes an incision in the chest to reach the heart.
A surgical ablation can further be of the following types:
Maze procedure: This is a combined procedure, which is performed while the patient is undergoing an open-heart surgery. In this, the surgeon makes small incisions in the upper portion of the heart and stitches them together to develop a scar tissue which stops abnormal signals.
Mini Maze: Most patients suffering from atrial fibrillation do not need an open-heart surgery. Hence, a mini maze is the perfect procedure in such cases. In this, the surgeon makes several small cuts between the ribs and guides the catheter to the problematic area through a camera. The catheter builds a scar tissue which helps regulate the heartbeat.
Convergent procedure: This approach combines catheter ablation and mini maze, where the surgeon makes an incision under the breastbone to allow the radiofrequency to reach the outside of the heart through the pulmonary vein.
AV node ablation: This procedure is recommended when all other options fail. In this, the surgeon aims to destroy the natural AV node via radiofrequency energy through the catheter. This will restrict the chaotic signals and then, the node will be replaced by a pacemaker implanted in the chest to deliver painless electric pulses to make heartbeats.
Atrial fibrillation can also be prevented provided certain lifestyle modifications are made early in time.