Ask an expert: what is an arrhythmia?

A heart that beats too fast, too slow or with an irregular rhythm can reveal arrhythmia, a condition that affects more than two million people in the UK.

Highly acclaimed consultant cardiologist, Dr Fu Siong Ng, explains what exactly is an arrhythmia, what are its noticeable symptoms, and how can arrhythmias be managed – with lifestyle changes and with medical treatment.

What is arrhythmia?

Arrhythmia is a broad term that really describes an irregularity or disorder of the heart rhythm. The heart beats 60 - 80 times a minute and about 80,000 times per day. It does this repeatedly and the heart rhythm is regulated by our natural pacemaker of the heart. However, in some occasions, that process can go a little bit awry causing some irregularities in the heart rhythm. That is, really, what we mean by an arrhythmia.

What are the symptoms of arrhythmia?

Arrhythmias can manifest in very different ways from very mild to very severe symptoms.

On the mild end, some individuals can have arrhythmias without knowing it. This is what we call asymptomatic arrhythmias, where patients have arrhythmias that are picked up really incidentally by chance, when they go to the hospital for another reason and have a heart test which reveals an arrhythmia. On the mild end of the spectrum, people can feel some irregularity in the heart rhythm, where they describe going to bed at night and feeling a bit of an odd sensation in the chest - a bit of irregularity in the heart.

Some patients can get more prominent symptoms. For example, some people feel periods where they get a few hours where the heart is beating very fast or very irregularly, which can be troubling for them.

Other symptoms include breathlessness, dizziness, tiredness.

On the severe end of the spectrum, some arrhythmias can be life-threatening, causing people to collapse and at the very worst case, leading to sudden death.

Is it a serious condition and does it have a cure?

There's a whole range of different arrhythmias, ranging from very benign to very serious arrhythmias. The majority of arrhythmias – and I would say over 90 per cent - are benign arrhythmias that are not life threatening. Sometimes, they cause symptoms that affect the quality of life but we can find the right treatments to help with this.

However, a very small minority of arrhythmias reflect something dangerous and an underlying issue with the heart. These are very serious arrhythmias, but they are a very small minority. That’s why it is important, when you have symptoms of arrhythmia, to get tested so that we can work out where you are on the spectrum.

In terms of the cure, we have many treatments available to help people with arrhythmias. The majority of benign arrhythmias can be treated very well and very easily.

With some of the more serious arrhythmias, we have ways of preventing dangerous outcomes, like implanting defibrillators to stop the very extreme manifestations of those dangerous rhythms.

Is arrhythmia a condition that people can be born with, or does it develop over time?

Again, there is a spectrum of arrhythmias. Some people are born with a predisposition to it, they are not born with the arrhythmia but they can inherit certain genes that affect how the electrics of the heart are regulated. Over time, they then become more at risk. Individuals with a family history of arrhythmias can have a higher chance of going on to develop arrhythmias. They aren’t born with arrhythmia; they are born with a predisposition.

However, the majority of arrhythmias are, what we call, acquired over time. As people age and as the heart ages with lifestyle in terms of weight, high blood pressure and other heart conditions, all of these factors are combined to increase the chance of arrhythmia. The majority of arrhythmias are acquired, but a minority are due to a predisposition that people are born with.

What is involved in the treatment process?

There's a whole range of different treatments for patients with arrhythmias. The first step, of course, is to get some standard testing to work out what type of arrhythmia a patient has. This involves a standard heart electrical tracing (ECG), an echocardiogram (heart ultrasound) to look at the heart function, and perhaps a heart monitor.

Once we identify the specific type of arrhythmias, we will direct the treatments towards it. I usually say there are four tiers of treatments for patients with arrhythmias.

For those with very mild arrhythmias that are benign and not worrying, we can sometimes leave it alone with actually no treatment, because we're not concerned about it and the patient is not troubled by it.

The next step is to have medication as and when needed - something called a pill in pocket approach - where you essentially carry a pill in your pocket and, as and when you get troubling symptoms, you can take that medication.

The third tier is to go on to regular medications. When symptoms are more severe, I say: “Why don’t you try a regular medication to stop the arrhythmia from coming on, rather than taking a pill when it happens?”

Then the fourth step is something invasive, we can perform procedures to try and fix the arrhythmia. For example, I perform a surgery called catheter ablation, a procedure where patients come into hospital for essentially a day-case procedure and we put catheters (long tubes) up from the vein in the groin up to the heart. Using those catheters, we record electrical signals from inside the heart and find out where the arrhythmia is coming from and we do something called ablation, where we perform control destruction of the heart muscle of the area causing the issue, and stopping that from recurring again.

There’s a whole spectrum of treatment options, depending on the type of arrhythmia and the severity of symptoms.

What can people who have heart arrhythmia do to improve their symptoms?

Again, it comes down to the specific arrhythmia, but there are many lifestyle changes that can help with different types of arrhythmias. One of the commonest arrhythmias I treat is atrial fibrillation, and that can respond to quite simple lifestyle changes.

There's also a lot of evidence now and I do a lot of research on this, showing that weight is very importantly linked to atrial fibrillation, where for every five units of body mass index increase you have, there’s a 20 per cent extra chance of having atrial fibrillation. A simple thing would be to have a healthy diet and lose weight, and I see some dramatic improvements just with that.

Alcohol has been shown to be linked to arrhythmias. Reducing consumption of alcohol in patients with arrhythmias can dramatically transform their lives and reduce the symptoms.

Also, sometimes people with sleep disorders such as obstructive sleep apnoea, if they treat the abnormal sleep breathing with a CPAP machine, it can also help with atrial fibrillation.

So, it’s not about just treating the arrhythmias itself, but it's about treating the risk factors and many of those can be treated with very simple lifestyle changes.

Dr Fu Siong Ng is a highly skilled consultant cardiologist based in London with specialism in a variety of heart conditions, including atrial fibrillation, atrial flutter, supraventricular tachycardia (SVT), ventricular tachycardia and cardiac device implantations. If you suffer from a heart condition and would like to consider your options, make sure to visit Dr Ng’s Top Doctors profile today.