What is Atrial Fibrillation (A-Fib)?
Atrial fibrillation is the most common heart rhythm disorder, caused by unusual electrical activity in the upper chambers of the heart, making them quiver or ‘fibrillate’. It’s a fast-rhythm type heart disorder where the heart rate is often high. This condition could either last less than seven days (paroxysmal) or more than seven days (persistent). Because of the irregular heart rhythm, the blood flow within the heart can become chaotic. This unpredictability increases the likelihood of a blood clot, which can break away, travel in the body, and potentially trigger a stroke. Atrial fibrillation is the top heart-related cause of stroke. Factors that elevate the risk of atrial fibrillation are age, hypertension, existing heart and lung diseases, congenital heart disease, and drinking excessive alcohol. Symptoms differ and can range from none at all to chest pain, palpitations, rapid heartbeat, breathlessness, nausea, dizziness, excessive sweating, and general tiredness. Even though atrial fibrillation might be a lasting condition, a variety of treatments and risk-reducing strategies are available to lower the likelihood of stroke in patients with persistent atrial fibrillation. Such treatments involve blood-thinners, heart rate controlling medications, rhythm stabilizing medications, resetting the heart’s rhythm, destroying the areas causing the issues in the heart, and other heart-related procedures.
What Causes Atrial Fibrillation (A-Fib)?
Atrial fibrillation, also known as AF, can have many different causes, but it’s often linked to other heart problems. Some common factors that can lead to AF are:
1. Getting older
2. Being born with a heart defect
3. Having a heart disease, such as problems with the heart valves, coronary artery disease, structural heart disease, or lack of blood supply to the heart.
4. Drinking lots of alcohol regularly
5. High blood pressure in the heart or lungs
6. Hormone disorders, such as diabetes, pheochromocytoma, and overactive thyroid
7. Certain genetic traits
8. Brain conditions, such as the aftereffects of a significant head injury or stroke
9. Stress on the heart – like when there’s an issue with the mitral or tricuspid valve, the left ventricle doesn’t work properly, or there’s a blockage in an artery in the lungs.
10. Having sleep apnea, which is when breathing stops and starts while sleeping
11. Inflammation of the heart – myocarditis and pericarditis
Any condition that causes inflammation, stress, heart damage, or lack of blood flow to the heart can lead to AF. In some cases, the cause of AF can be related to a treatment or procedure a person had.
Atrial fibrillation is considered recurrent when a person has had two or more episodes.
There are three types of atrial fibrillation:
1. Paroxysmal AF: This is when recurrent AF goes away on its own, typically within seven days. This kind of AF is common in younger patients and involves electrically active areas in the pulmonary veins. Treating these areas can be effective as it takes away the trigger for the AF episodes.
2. Persistent AF: This is when recurrent AF lasts for more than seven days and needs medication or a procedure to restore a normal heart rhythm. If it comes with a fast and uncontrollable heart rate, it may cause the heart to expand, which is called dilated cardiomyopathy. This type of AF could be the first episode or a result of multiple episodes of paroxysmal AF.
3. Long-standing persistent AF: This is when AF has been present for more than 12 months, either because treatment hasn’t commenced yet or attempts to restore a normal heart rhythm have not been successful.
4. Permanent AF: This is the kind where all treatments have been stopped because the irregular heart rhythm is not responsive.
Risk Factors and Frequency for Atrial Fibrillation (A-Fib)
Atrial fibrillation is the most common heart rhythm disorder seen by doctors. The number of people with atrial fibrillation has been growing globally and is expected to double or even triple by 2050. The condition is more common in older individuals, with about 9% of those over 75 being affected. Once a person reaches 80, their chances of developing this disorder increases to 22%. Atrial fibrillation is also more commonly found in men and is seen more in white individuals than in black individuals.
- Atrial fibrillation is the most common heart rhythm disorder.
- Global cases are increasing and could double or triple by 2050.
- The condition is more common in older people, affecting 9% of those over 75.
- At 80 years old, the risk of developing it jumps to 22%.
- It is more common in men.
- It is seen more in white individuals than in black individuals.
Signs and Symptoms of Atrial Fibrillation (A-Fib)
Atrial fibrillation, also known as AF, can lead to serious health complications if not diagnosed and treated early. Symptoms can range from lack of noticeable signs to significant issues such as heart-related shock and stroke. As such, medical history and physical examinations are crucial in diagnosing and assessing the severity of the condition.
During the initial evaluation, doctors will ask about symptoms like heart palpitations, chest pain, difficulty breathing, swelling in the lower limbs, fatigue during physical activity, and dizziness. They also need to understand your personal medical history, especially any risk factors including high blood pressure, previous heart problems, sleep apnea, obesity-related breathing issues, smoking, alcohol or illegal drug use, past incidents of rheumatic fever or heart disease, pericarditis, and high cholesterol levels.
For patients who already have AF, doctors will ask about:
- How long and how often you experience symptoms
- What triggers your symptoms
- Previous successful treatments
- If you’ve used anti-arrhythmic drugs
- Previous instances of heart disease
Generally, the first step of the physical examination involves assessing your airways, breathing, and circulation to understand how they might affect treatment decisions. Then, they’ll check your pulse and heart rate, with a typical range of 110 to 140 beats per minute for an AF patient. They will also examine your upper and lower limbs for signs of swelling, evaluate your skin and hair for indicators of peripheral vascular disease, and pay attention to how the condition may have affected your overall wellbeing.
Later in the examination, the doctor will aim to identify the cause of your AF. This involves checking your neck for any signs of carotid artery disease or thyroid issues, examining your lungs for signs of heart failure or past lung conditions such as asthma or chronic obstructive pulmonary disease (COPD), and assessing your heart by listening and feeling for any irregularities. Abdominal exams are conducted to check for potential issues such as an enlarged liver or swelling, which could indicate heart failure, as are neurological exams to watch for signs of transient ischemic attack or stroke.
Testing for Atrial Fibrillation (A-Fib)
Atrial fibrillation, a heart condition often diagnosed through a combination of your health history, physical examination, and an electrocardiogram (ECG) – a type of heart test. On an ECG, atrial fibrillation shows a distinctive ‘irregularly irregular’ pattern with narrow complex waves, without identifiable ‘p-waves’. You might also see waves linked to fibrillation, but they might not always be present. The heart rate typically falls between 80 and 180 beats per minute.
Your doctor might also need to take blood samples to help determine the cause of atrial fibrillation. Tests might include a complete blood count (CBC) to check for infections, basic metabolic panel (BMP) to find any electrolyte imbalances, and thyroid function tests to see if overactive thyroid is a factor. A chest x-ray may be requested to look for any chest issues.
Atrial fibrillation is commonly seen in people with heart diseases, so your doctor might need to rule out any underlying heart issues. This could involve testing your blood for specific heart disease markers or a molecule called B-type natriuretic peptide (BNP). In some cases, you might need a procedure known as cardiac catheterization, which involves threading a long tube through your blood vessels to your heart.
Your doctor may also want to determine if you have a lung blood clot, known as a pulmonary embolism, since this can affect how your atrium, a part of your heart, functions leading to atrial fibrillation. Tests for this might include a blood test called a d-dimer test or a special kind of CT scan. Doctors also use specific criteria called the PERC and/or Wells criteria to determine your risk of pulmonary embolism.
Additionally, an ultrasound test of your heart, known as a transesophageal echocardiogram (TEE), may be necessary. This test can help your doctor see if there’s a blood clot in your heart, which is a potential complication of atrial fibrillation, and to evaluate the structure of your heart. It’s especially important to have this test done before any procedures to reset your heart rhythm are performed, to reduce the risk of stroke.
Treatment Options for Atrial Fibrillation (A-Fib)
The treatment of a heart condition known as atrial fibrillation largely depends on the patient’s overall health and their risk assessment. In serious cases where the patient’s blood circulation is not stable, a procedure called cardioversion, combined with anticoagulant therapy to prevent blood clots, may be needed immediately. Although a type of ultrasound scan (TEE) is usually performed before cardioversion, it may be skipped if the condition is severe due to rapid heartbeat. In cases of rapid heartbeat, medications such as beta-blockers or calcium-channel blockers are often used to control the heart rate.
These medications can be administered intravenously for a quicker effect. If symptoms persist, the patient might be put on an IV drip. Although digoxin could also be used to control the heart rate, it’s usually not the first choice of treatment due to its potential side effects. Another option, amiodarone, can help regulate heart rhythm but isn’t typically used first in an emergency. If it is considered, a cardiologist needs to be consulted before it’s administered.
If the patient already has a history of atrial fibrillation, then their risk of having a stroke can be estimated using the CHADs-2-Vasc score. Based on this score, the patient is classified as “low-risk” (score of 0), “low-moderate risk” (score of 1), or “moderate-high risk” (score of more than 2). This score helps determine whether they should receive anticoagulant (blood-thinning) medication. A number of different medications, including beta-blockers, calcium channel blockers, and amiodarone, can be chosen for this purpose. Another assessment, the HAS-BLED score, can help evaluate the patient’s risk of bleeding if anticoagulant therapy is considered.
Some patients with atrial fibrillation may require treatment other than medications. This might include ablation therapy, which uses heat or cold to create small scars in the heart to prevent abnormal electrical signals. In severe cases, where atrial fibrillation has caused heart failure, a pacemaker might need to be inserted.
There are several guidelines to follow for managing patients with atrial fibrillation. They generally recommend:
– Oral anticoagulation for patients with an elevated risk of stroke.
– Non-vitamin K oral anticoagulants are preferred over warfarin, with some exceptions.
– Aspirin is not recommended for patients with a low risk of stroke.
– Special medications are recommended to reverse the effects of some anticoagulants if an urgent procedure needs to be performed or bleeding occurs.
– In patients where long term anticoagulant therapy is not suitable, a procedure to close off a small pouch in the heart (percutaneous left atrial appendage occlusion) may be recommended.
– If the patient’s atrial fibrillation has been ongoing for more than 48 hours or the duration is unknown, start anticoagulation therapy.
– Catheter ablation is an option in patients with a low ejection fraction, which is a measure of how well the heart is pumping out blood.
– Weight loss is recommended in obese patients with atrial fibrillation.
What else can Atrial Fibrillation (A-Fib) be?
Taking a patient’s medical history and conducting a physical examination are vital in determining the different causes of a condition known as atrial fibrillation. Electrocardiogram (ECG) readings, which captures the heart’s electrical activity, are fundamental in identifying the root cause of this disorder.
When diagnosing atrial fibrillation, doctors will consider several conditions that may present similar symptoms. These include:
- Atrial flutter: This can be similar to atrial fibrillation, but the rhythms of the heartbeats differ. In atrial fibrillation, the beats are irregular and chaotic, and the normal signals (P-waves) that indicate the heartbeat on an ECG are not seen. On the other hand, atrial flutter has a more organized and regular rhythm, but still lacks these P-waves.
- Atrial tachycardia: This is a fast heart rate that starts in the upper chambers of the heart.
- Multifocal atrial tachycardia: This condition is characterized by multiple sites in the heart’s upper chambers firing signals at the same time, causing a rapid heart rate.
- Wolf-Parkinson-White syndrome: This is a condition in which there’s an extra electrical pathway in the heart, leading to episodes of rapid heart rate.
- Atrioventricular nodal reentry tachycardia: This is another type of rapid heart rate disorder caused by an electrical signal that travels an abnormal pathway in the heart.
It’s critical that the doctor carefully consider these potential conditions and conduct the necessary tests to ensure an accurate diagnosis.
What to expect with Atrial Fibrillation (A-Fib)
AF, or atrial fibrillation, comes with high risks such as blood clots and even death. Research has shown that managing the rhythm of the heart does not necessarily offer a better chance of survival than just managing the heart rate. Over their lifetime, individuals with AF often get admitted to the hospital multiple times and may encounter complications related to blood-thinning interventions. They are always at risk of having a stroke.
Apart from the medical implications, the overall quality of life for patients with AF is typically not satisfactory. Plus, the treatment of atrial fibrillation can be quite expensive. Unfortunately, most of these costs have to be shouldered by the patient.
Possible Complications When Diagnosed with Atrial Fibrillation (A-Fib)
The main adverse outcome from abnormal heart rhythm, specifically atrial fibrillation, is a stroke. This refers to interruptions in blood flow to the brain, also known as cerebral vascular accidents (CVA), which can seriously impact health and even be life-threatening. The good news is that the risk of experiencing CVA can be lowered notably through the use of blood-thinning medications, often combined with therapies to manage heart rate or rhythm. The other potential problems could be heart disease and deterioration of the heart’s ability to pump blood, known as heart failure.
Common Side Effects:
- Stroke
- Cerebral vascular accidents (CVA)
- Heart disease
- Heart failure
