Introduction

What is atrial fibrillation?

Atrial fibrillation (AF) is an abnormal heart rhythm, where your heart beats unsteadily, and it affects millions of people around the world.¹ It is the most common type of arrhythmia (abnormal heartbeat), meaning your heart either beats too slow, too fast or in an irregular way. This can lead to symptoms like dizziness, tiredness or shortness of breath. 

Different types of AF

1. Paroxysmal (episodes that start and stop within 7 days of onset on their own)¹
2. Persistent (symptoms lasting longer than 7 days)
3. Long-standing persistent (when symptoms last at least 12 months)
4. Permanent (symptoms can be felt all the time, even when on treatment)¹

There are two main strategies used to manage the condition: rate control and rhythm control. Both management aims to help improve your symptoms and reduce your risks of further complications, and also improve your quality of life living with AF. This article will focus on diagnosing the rate and rhythm control management of AF and comparing each treatment strategy.

Atrial fibrillation is not life-threatening; however, it can increase your risk of developing blood clots in the heart. This, in turn, increases the chance of you developing a stroke.² Having AF makes you five times more likely to have a stroke if it is not diagnosed early.² A study was carried out on patients who had suffered a stroke, and it found that roughly 23.7% ultimately were found to have underlying AF.³

Main symptoms of AF include:

• Lightheadedness or dizziness 
• Heart skipping or missing beats (palpitations)
• Feeling tired 
• Chest pain or tightness
• Shortness of breath

However, AF is often asymptomatic, undetected, and undiagnosed²

Please ensure you speak to a healthcare professional or seek urgent medical assistance if you have any of these symptoms.

Diagnosis and investigations

You may present to your healthcare professional with the symptoms listed above, and they will:

• Take a full history, asking questions about the onset, nature, duration, severity, and impact of your symptoms. They may also want to know if you have any underlying medical conditions which increase your risk of developing AF.

Atrial fibrillation is frequently associated with conditions that change the structure of the heart ¹ for example:

Risk factors of AF

• High blood pressure
• Heart failure
• Thyroid disease
• Obesity
• Diabetes 

Following the history taking, the healthcare professional may want to perform an examination. This may involve checking your pulse and listening to the heart for the number of beats in a minute, rhythm (regularity of the heart beats) and murmurs. They will also listen to your lungs to check for any signs of heart failure. 

To confirm whether you have AF, a 12-lead ECG is conducted. This is a test that measures your heart's activity, and it presents on an ECG with absent P waves and an irregular R–R interval.⁴

In order to diagnose paroxysmal AF, this is best achieved by doing an ambulatory ECG. This can be done for up to 7 days, depending on how often you have your symptoms.

Treatment

If you have a new or an acute onset of AF, it needs to be treated urgently. This may require emergency hospital admission if the individual has:

• New-onset AF within the past 48 hours and is hemodynamically unstable (insufficient blood flow to a person's body).
• Severe symptoms of AF due to rapid (more than 150 beats per minute) or very slow (less than 40 beats per minute) heart rate.
• A severe underlying cause of AF, such as stroke or transient ischaemic attack (TIA/mini stroke). 

A timely assessment needs to be carried out to assess the risk of developing a blood clot, as this is essential to AF management due to the fivefold increased risk of stroke compared with the general population.⁴ This is usually based on the clinical prediction tool CHA2DS2-VASc score.  The scores are used to predict the risk of stroke and provide an estimate of the risk of thrombosis in a population at similar risk to the patients reviewed.⁴

Two main types of treatment and management for AF

1. Rate control
2. Rhythm control

Rate control: Slowing the heart down 

This is one way to manage persistent AF without changing the heart rhythm from irregular to regular (normal). The goal is to relax and slow the heart rate down so it is not beating excessively fast. Although the heart is still beating irregularly, you may begin to feel much better as your heart is beating at a relaxed pace. The rate control is defined as the use of any combination of medications known as beta blockers, calcium channel blockers, and digoxin ⁴. It is an essential part of AF management. 

Examples of each medication

• Beta blockers - Metoprolol, Bisoprolol or Atenolol
• Calcium Channel Blockers - Diltiazem and Verapamil 
• Digoxin - used in the elderly or if you also have heart failure. 

These medicines help lower the number of heartbeats per minute and reduce symptoms of shortness of breath, palpitations and tiredness. It is also a preferred choice if you do not have any physical symptoms.¹ It is usually administered intravenously (IV) when you first present to the emergency department, but it is then given orally for longer-term management.¹

The list mentioned above is usually the first‑line treatment strategy for AF, except for those:

• Whose atrial fibrillation has a reversible cause
• Those who have heart failure, thought to be primarily caused by atrial fibrillation
• With new‑onset atrial fibrillation
• With atrial flutter, a condition that is considered suitable for an ablation strategy to restore sinus rhythm or
• For whom a rhythm‑control strategy would be more suitable, based on clinical judgement

This type of management can be enough to improve how your symptoms feel daily, and it is a simpler approach to reduce hospital visits and has fewer side effects than rhythm control. However, some people find that even though their heart rate is controlled at a calmer pace, they are still experiencing symptoms. They may then be offered treatment for rhythm control.

Rhythm control - Restoring a normal heartbeat 

This treatment strategy is used to try and bring your heart rate back to a normal, regular rhythm and maintain it. It is also used if your symptoms continue after the heart rate has been controlled or if the rate‑control strategy has not been successful at all. The aim is to stop AF completely and help the heart beat regularly again, and it is used if you are symptomatic.⁴

Once diagnosed with AF, you will be required to have routine check-ups to ensure your symptoms are stable and under control. This is because rhythm control management is known to have more side effects and a lower success rate.¹

Types of rhythm control: Antiarrhythmic drug therapy, Cardioversion and Left atrial ablation - the type of treatment you get is based on age, symptoms and other medical conditions you may have.¹

Antiarrhythmic drug therapy

• Medications are used to help maintain a normal heart rhythm. Examples of this: Class I sodium channel blocking agents (flecainide, propafenone, disopyramide) - should NOT be used in patients with heart failure or coronary artery disease¹
• Class III agents - Sotalol, Dofetilide, Amiodarone

Cardioversion

There are two types of cardioversion; 

1. Electrical cardioversion 
2. Pharmacological cardioversion (also known as chemical cardioversion)

Electrical cardioversion is a treatment that delivers electrical energy (shock) to the heart using an external defibrillator to get the heart back into its normal rhythm. This is done by attaching electrodes (sticky pads) to the chest to deliver a quick electric shock, and can be very effective in many patients ⁵. This is usually done under short general anaesthesia and can last for a few minutes. 

Pharmacological cardioversion is a treatment using medication. You may swallow the medicine or receive it through an intravenous infusion (also known as an IV). An IV is when medicine is directly injected into your veins.⁵

Amiodarone therapy (medication used to treat or prevent heart rhythm disorders) should be considered starting 4 weeks before and continuing for up to 12 months after electrical cardioversion to maintain the heart's normal rhythm, and discuss the benefits and risks of amiodarone with the patient.

Cardioversion management is usually planned; however can be done if needed in an emergency for severe symptoms.

Summary

Atrial fibrillation (AF) is the most common heart rhythm disorder, increasing the risk of stroke and affecting quality of life. Persistent AF lasts more than 7 days and requires ongoing management. Two main treatment strategies exist: rate control and rhythm control.

• Rate control slows the heart rate without restoring normal rhythm. Medications include beta blockers, calcium channel blockers, and digoxin. It is the first-line option in most cases and helps relieve symptoms like palpitations and breathlessness
• Rhythm control aims to restore and maintain a normal heart rhythm. It’s used when rate control fails or symptoms persist. Methods include antiarrhythmic drugs (e.g. amiodarone, flecainide), cardioversion (electrical or chemical), and procedures like ablation

Diagnosis involves a full medical history, ECG, and risk assessment for stroke using the CHA₂DS₂-VASc score. AF is often linked to other health issues such as hypertension, diabetes, and heart failure. Early diagnosis and appropriate treatment improve outcomes and reduce stroke risk.

Both rate and rhythm control strategies aim to reduce symptoms and improve quality of life, with the best approach tailored to individual patient needs.