Based on a Pew Research Center poll conducted June 3-17, 2019, almost one U.S. adults (21%) indicate they routinely wear smartwatches or wearable fitness trackers as 2020 commences and health-related New Year's resolutions happen immediately.

Smartwatch's heart rate monitors can be useful for measuring your fitness, but can they be used to monitor an abnormal heart? The quick answer is yes, depending on who you are. These devices are fantastic, but there are several things users should be aware of. Several big trials have been performed to see how effectively wearables can detect signals of "atrial fibrillation," a frequent heart rhythm disorder that can lead to stroke.

In the latest Frontiers review published in Circulation, the researchers, alongside colleagues from the International AF-Screen Collaboration, assess the current evidence, including findings from three large studies: the Fitbit Heart Study (funded by Fitbit), the Apple Heart Study (supported by Apple), and the Huawei Heart Research (Huawei participated in the development and optimization of the app but did not finance the study).

Atrial Fibrillation: Definition and Diagnosis

The most prevalent cardiac rhythm disorder is atrial fibrillation (arrhythmia). Up to 80% of people may have no symptoms.

Atrial fibrillation grows more frequently with age and considerably increases the risk of stroke. Patients at high risk of having an atrial fibrillation-related stroke due to their age and/or additionally associated with increased risk, such as hypertension and diabetes, are usually on blood-thinning medication.

Consumers are becoming able to obtain equipment for documenting cardiac arrest. Portable electrocardiograms (ECG) with pulse-based technologies in smartwatches, other wearables, and portable consumer gadgets are promoted as "health and lifestyle" products.

As reported by Mirage News, the Australian and international recommendations encourage frequent monitoring for atrial fibrillation in persons aged 65 and over. However, modern technology (such as wearables) enables users to record their ringtones anytime they choose and regularly check the correctness of their pulse. This technology has the potential to empower people and deliver crucial information, but it does have drawbacks.

A new study claims that smartwatches and other wearables with ECG can monitor irregular heartbeat that can lead to atrial fibrillation.
(Photo: Dragana Gordic / Shutterstock)
A new study claims that smartwatches and other wearables with ECG can monitor irregular heartbeat leading to atrial fibrillation.

ALSO READ: Smartwatches Can Detect Atrial Fibrillation; How Accurate Are the Results These Devices Can Produce Compare to ECGs?

Accuracy of Wearables and Smartwatches

The quick answer is that wearables are accurate (typically over 95%) at detecting atrial fibrillation. However, the data is frequently based on research on small groups of people.

Some gadgets have an algorithm that informs you if your heart rhythm is regular ("normal sinus rhythm") or abnormal (which may indicate atrial fibrillation). These algorithms often require regulatory permission (for example, from Australia's Therapeutic Goods Administration (TGA).

However, gadget manufacturers frequently do not share many facts regarding their devices' accuracy and functionality. The TGA does not regulate wearables that measure heart rate or exercise without making claims concerning severe diseases.

While the Fitbit, Apple, and Huawei trials are substantial, the data used to assess the device's accuracy can be based on tiny numbers because there aren't many participants in the research who have atrial fibrillation.

Smartwatch Can be Fit for Certain Users

The Apple Heart research, for example, included 419,000 participants in all - that's a lot of people! However, only 86 participants were tested for accuracy by analyzing concurrent readings with atrial fibrillation on a wristwatch pulse abnormality detector and an ECG patch.

If an individual has indications or is over 65, smartwatches can be quite helpful in detecting atrial fibrillation. Wearables are ideal as an "event recorder" for anyone experiencing symptoms of an arrhythmia (such as heart palpitations). ECG-capable devices, such as the Apple Watch Series 4 or later, the Withings Scanwatch, and the KardiaMobile, are very useful since they give additional information. If users have an ECG recording during discomfort, they can give it to their doctor to assist guide treatment, following the report from The Conversation.

Smartwatch devices provide more heart-rate data than ever before, but it's not always apparent how to interpret it. Wearables can also assist patients in acquiring a timely detection of atrial fibrillation. This should ideally be accompanied by integrated treatment, which includes risk factor reduction and lifestyle improvements (especially appropriate for young people who may need no specific therapy) to prevent progression and problems.

Researchers also know that wearables can be used to screen many people: 457,000 in the Fitbit trial, 419,000 in the Apple Heart research, and 188,000 in the Huawei study. However, because the research participants were so young, the newly identified atrial fibrillation yield was modest (less than 1%).

Smartwatches Drawbacks and Data

Additional information is not necessarily better. Suppose one's doctor measures someone's pulse during the visit and finds it irregular, or the ECG confirms that you have atrial fibrillation. In that case, users are most likely experiencing it often (or all the time).

The dangers of atrial fibrillation are the same for persons with and without symptoms, and we know how to manage the illness. On the other hand, wearables may monitor a person's heartbeat often and for an extended time. The more people look, the more they find atrial fibrillation, but the researchers indicate that it's not sure if it's acceptable, as per the US Today report.

Even the most effective and efficient devices can and do produce false positives, most commonly in young persons who have a low chance of developing atrial fibrillation. Diagnostic checks may be required, increasing the expense and maybe leading to an unwanted test that causes difficulties and raises worry.

Privacy protection is also an issue. Many nations have severe legislative gaps in data protection and applicable regulation. Consumers frequently do not own or process information from healthcare applications. If the user's equipment indicates that they might have atrial fibrillation, duplicate the reading and consult with a specialist. More tests or therapy may be required.

RELATED ARTICLE: Atrial Fibrillation High-Risk Group Revealed in Study Involving a Million Patients

Check out more news and information on Wearables in Science Times.