Lots of people are already using wearable tech to measure their heart rate, but Apple’s latest smartwatch is taking things to a whole new level. The Apple Watch Series 4 will feature a built-in electrocardiogram, or ECG, which means as well as tracking heart rate, it’ll be able to detect potential arrhythmias or abnormal heart rhythms – including Atrial Fibrillation, a major cause of stroke.

In terms of consumer health tech, this is pretty ground-breaking so it’s no surprise it’s got people talking. But why is it relevant? Here’s a look at some of the key points:

What is an ECG?

If you’re sent for an ECG at hospital, you’ll usually be asked to lie down while electrodes are attached to your chest, wrists and ankles. These will take a recording of your heart’s rhythm, rate and electrical activity. Where heart rhythm abnormalities are occurring intermittently – for example, somebody’s experiencing palpitations or an irregular heartbeat at certain times of the day or after exercise – they might be given a monitor to wear for a few days, or an ‘exercise ECG’ where the test is carried out on a treadmill.

What can ECG findings show?

The main purpose of an ECG is to capture abnormalities that may indicate problems that need to be investigated further or treated, including with the heart’s size, valves and blood flow, as well as helping detect arrhythmias. The Apple Watch Series 4 won’t be a full match for the tests and analysis you would undergo in a clinic, but one of the key things that’s got people talking is its ability to detect Atrial Fibrillation (AF).

What is Atrial Fibrillation?

Here, in this video, leading London heart specialist Dr Syed Ahsan, explains what atrial fibrillation (AF) is.

Atrial Fibrillation is one of the most common heart rhythm disorders, affecting around one million people in the UK, mostly aged 65 and over. It’s characterised by a very fast, irregular heartbeat which may come and go or be almost constant in severe cases, due to problems with the electrical activity originating in the heart’s top left chamber/atrium. As well as our information video above, you can read more about Atrial Fibrillation in our conditions pages.

A silent killer?

AF is sometimes referred to as a ‘silent killer’ because it’s a major risk factor in life-threatening conditions like stroke. With AF, the heart isn’t able to pump as efficiently so blood can ‘pool’ in the upper chambers and clots might form – yet thousands of people don’t even realise they have the condition or how serious it can be. This is because while some people with Atrial Fibrillation may experience mild to severe symptoms such as breathlessness and dizziness, sometimes it doesn’t cause any symptoms at all.

A treatable problem

The good news is, AF is very simple to diagnose and can be treated and managed. It’s believed that better awareness and detection of the condition could prevent thousands of strokes a year in the UK. Our information video on the treatment options for AF explains more.

Is wearable tech part of the solution?

Anything that helps improve awareness of Atrial Fibrillation and helps people engage in managing their heart health is, on the surface at least, a positive thing. In terms of the Apple Watch’s potential to help save lives, it’s far too soon to say and more data and research will be needed. What is crucial, however, is that people remember: While smartwatches may be able to play a role, they are not a replacement for seeing a doctor, and self-diagnosing is never advised – so if you have any concerns, always get them thoroughly checked out.

Leading London cardiologist Dr Syed Ahsan sees patients with a wide range of heart conditions. If you or a loved one is experiencing any symptoms that may indicate an arrhythmia, such as breathlessness, dizziness and an irregular pulse, book a consultation.