Ever felt like you’ve worked too hard at the gym, or maybe you’ve had too much coffee before a big presentation, and your heart is racing or has skipped a beat? 

There could naturally be times in life where you find yourself feeling a rush of the moment, causing your heart to experience a harmless interruption in its beat. Or, it could be quite literally that your heart repeatedly skips a beat, a sign of a deeper issue. This could be explained by persistent atrial fibrillation, a condition with varying causes and often embedded in hidden heart and systemic issues.

What is persistent atrial fibrillation? 

Persistent Atrial Fibrillation (AF) is the most common type of abnormal heart rhythm, also known as an arrhythmia, that causes the heart to beat rapidly or in an irregular pattern.¹ It is caused by a defective electrical system that creates the heartbeat. 

There were approximately 1.5 million people living with AF in the UK in 2020, which is higher than the number of people recorded as having heart failure in the same year, and the number of people living with AF is known to be increasing yearly.² Hence, understanding how AF  occurs is crucial, as this allows the condition to be effectively recognised and treated without delay. 

The key symptoms of persistent AF include:^1,3

• A sudden feeling of the heart racing, pounding, or skipping a beat, which lasts more than a few seconds, is also known as palpitations
• A heartbeat of more than 100 beats per minute
• Feeling unusually or extremely tired 
• Shortness of breath, making it harder to exercise 
• Chest pain
• Dizziness or fainting

Persistent AF can sometimes show no symptoms and be discovered in a routine check-up, and there are different ways that symptoms can present. It may be that symptoms manifest as episodes where they begin on their own but also end on their own with no treatment, known as paroxysmal AF.³ Alternatively, it could be that symptoms stop following treatment, but they last for more than seven days.³ In some cases, symptoms could always be present and do not stop after treatment with medication or surgery, which is known as persistent AF, or long-standing AF if the symptoms persist for over one year.¹ 

Even though persistent AF is not a life-threatening condition, it does make you five times more likely to have a stroke, and it can create blood clots in the heart, which prevent blood cells from getting enough oxygen for their survival.¹ AF has been reported to be the most frequent heart-related cause of stroke.² Understanding the causes or triggers can reduce the risk of stroke, so AF can be recognised quickly and better managed for optimal health.

The science behind the chambers 

Picture a house with two floors: each floor has two bedrooms, and each bedroom has strong doors. The house is reinforced with a layer of insulation, the bedrooms are reinforced with thick walls, the floors are connected with stairs, and you have working electricity for you to go about your essential daily tasks.

Similarly, your heart is divided into four main chambers, with a series of vessels or ‘doors’ for blood to flow through, and it is managed by a system of electrical signals that together control the pace and rhythm of its beat. These signals first pass through the two upper chambers of the heart, called the atria, down to the lower chambers, called the ventricles.⁴ 

In the hearts of people affected by persistent AF, these electrical signals are not steady or controlled in the atria; rather, they are weak or twitching, known as ‘fibrillation’.¹ This causes the lower chambers, the ventricles, to pump too quickly, creating an irregular heartbeat.⁴ It is crucial that the heart beats in a regular, controlled rhythm so that it can perform its crucial role in pumping enough oxygen-rich blood around the body. 

What causes persistent atrial fibrillation?

There are known to be many causes of persistent AF, also known as ‘risk factors'.¹ However, in some cases, the cause of persistent AF may not be known or be difficult to pinpoint due to no obvious or an unexplained cause, or a mixture of different risk factors.²

These causes can generally be divided into 3 subgroups: underlying heart conditions, other systemic health conditions, and lifestyle factors.

Heart conditions that can cause AF

The majority of people living with AF are known to have an underlying heart condition.² Pre-existing damage to the heart acts as a primary trigger and directly creates an irregular heartbeat, resulting in persistent AF as a secondary condition.^1,3 Underlying heart conditions that can cause persistent AF include:^1,4

• Heart failure
• High blood pressure
• Congenital heart disease: altered structure or blood flow of the heart present from birth, such as a hole in the heart or incorrect number or location of valves
• Coronary artery disease: caused by blockage of arteries, a type of blood vessel in the heart, resulting in reduced blood flow to the heart
• Pericarditis: inflammation of the protective outer lining that covers your heart
• Heart valve disease:  inadequate function of the valves or ‘doors’ that control the direction of blood flow between the heart’s chambers, such as leakage or narrowing
• Cardiomyopathy: the thickening of the myocardium, a muscle in the wall of the heart that is responsible for pumping blood out of the heart to the rest of the body. This thickening causes stiffness, making it difficult for the heart to pump blood to the body
• Heart surgery 

Systemic health conditions causing AF

Other health conditions related to different areas or ‘systems’ in the body outside of the heart can also cause persistent AF.¹

The body is made up of different systems of organisation that work together to give us life and allow us to function the way we do. For example, the nervous system is responsible for the coordination of all actions and reactions, and the respiratory system controls your breathing to keep you alive. Sometimes, damage to one or more parts of these systems can affect the whole body and cause health conditions that further result in persistent AF.⁴ These health conditions include:^1,4

• Lung conditions such as Asthma, Lung cancer, Chronic Obstructive Pulmonary Disease (COPD): Inflammation, specifically in the lungs and the airways, causes them to become narrowed and also results in a lot of thick mucus, damaged air sacs, and reduced levels of oxygen entering the blood, which can put a strain on the heart⁴
• Hyperthyroidism: an overactive thyroid can make you three times more likely to develop AF.⁵  High levels of hormones produced by the thyroid can cause a faster heart rate, which makes it difficult for the heart to rest and return to its normal controlled state after it has pumped blood out to the rest of the body⁵
• Diabetes: high levels of sugar in the blood, coupled with inflammation and changes in the structure of the atria, can cause irregular heartbeat. About 30% of people experiencing AF are those who also live with diabetes, highlighting how important it is to control diabetic factors and lifestyle choices⁶
• Pulmonary embolism: The pulmonary arteries in the heart are blood vessels that carry blood from your heart to the lungs to receive oxygen. When a blood clot forms and travels towards the lungs, it can lodge itself in the pulmonary artery, blocking the flow of blood. This forces the heart to work harder to ensure blood is pumped to the lungs, which can strain the heart⁷
• Kidney disease: conditions that affect the kidney can repeatedly activate the nervous system. This is responsible for controlling our responses to external triggers, known as the ‘fight-or-flight’ response that protects us in times of stress. Too many stress responses lead to increased palpitations in the heart and can disturb the heart’s electrical system, potentially resulting in a stroke⁸
• Metabolic conditions: this is a group of conditions that increase your risk of heart disease, diabetes and stroke. These are often associated with persistent AF due to various factors such as obesity, inflammation, and high blood pressure, which cause changes to the structure of the atria⁹
• Sleep apnea: frequent pauses in regular breathing during sleep cause a momentary drop in your oxygen levels. Over time, this lack of oxygen causes frequent changes in the pressure within the chest, putting stress on the heart and increasing the risk of irregular heartbeat⁴

Lifestyle or environmental risk factors 

Some lifestyle choices we make can actually be triggers for persistent AF, as they can lead to inflammation or stress on the heart.² On the other hand, some factors that are inevitable and uncontrollable, such as old age and gender assigned at birth, can also trigger AF persistent AF is more common in people assigned male at birth (AMAB) who are aged 55 or over.³

Lifestyle factors that can result in persistent AF include:^1,3,4

• Stress
• Obesity
• Smoking, taking recreational drugs, alcohol, and caffeine
• High intensity exercise 
• Spicy food

As we are very much in control of these lifestyle factors and how they can affect our health, it is crucial to keep them in moderation so that if they are found to cause persistent AF, it can be controlled. 

Summary

Persistent AF is a manageable condition that does not always reduce the quality of life. Monitoring your symptoms and checking your pulse is vital when you feel any disturbances in your heartbeat or frequent palpitations. Speak to your healthcare professional if you have any concerns so that they can perform the necessary checks to ensure your heart is functioning as it should. Avoiding any triggers that affect your heartbeat and taking preventative measures through ensuring a balanced diet and regular exercise can help you continue to live a healthy and active life. 

You could very well take the first step in managing your health today! Taking the Klarity chronic disease risk assessment can help you understand your current lifestyle and receive advice on how to manage any symptoms, all to help you live the best life you can.