Newer smartwatches aren’t just for your weather and step goals anymore – they may now be able to detect certain heart arrhythmias, including Afib. In this post, we will discuss what is Afib, what are the benefits and drawbacks of this new technology, and what an abnormal heart rhythm notification on your smartwatch may mean.
What is Afib?
Atrial Fibrillation (also known as AFib or AF) is the most common type of heart arrhythmia. An arrhythmia is another way of saying irregular heartbeat.
Normally the heart requires regular electrical activity for the heart to pump consistently. Instead, a person’s heartbeat during Afib is often fast and irregular, and there can be complications of the heart not pumping correctly.
Why should I be concerned about Afib?
Even if you have no noticeable symptoms, you are nearly 2.5 times more likely to have a stroke than a person without AFib. Afib can also lead to blood clots, heart failure, and other heart-related complications. Once Afib is diagnosed by a cardiologist or your primary care provider, thankfully there are medications you can take to decrease the risk of stroke and other complications. That is why detection is so important.
What symptoms should I look out for?
The most common symptom is a quivering or fluttering heartbeat. Some people may not feel these symptoms and their Afib is only detectable upon exam by your doctor.
What are other less common symptoms of Afib?
Other less common symptoms include fatigue, a rapid and irregular heartbeat, fluttering or “thumping” in the chest, dizziness, shortness of breath, weakness, faintness or confusion, fatigue when exercising, sweating, or even chest pain. If you are experiencing any of these symptoms, it is important to get checked out by your provider. You should go to the ER if you are experiencing chest pain for a full evaluation as it may be a sign of something more serious.
How do you detect and diagnose Afib?
The best tool for the diagnosis of Afib is an ECG (electrocardiogram), which is a painless, non-invasive way to record the electrical activity of the heart. The irregular electrical signal produced during Afib is recorded by an ECG; a cardiologist or primary care provider then reviews or “reads” the ECG and diagnoses the arrhythmia as Afib.
How do the smartwatch’s ECG work?
Most smartwatches have a tiny ECG that works a little differently than your traditional ECG in your doctor’s office. Your smartwatch ECG uses flashing lights to penetrate the skin and detect blood flow. When light is reflected off the flow of blood, it’s captured by the sensor. An algorithm interprets the sensor’s data to determine your heart rate and detect Afib.
How is a smartwatch’s ECG different from a regular ECG? What are limitations of using a smartwatch to detect Afib?
To provide a little more background, usually an ECG uses 12-leads, meaning 12 electrodes or sensors that are applied to your skin to detect your heart’s electrical activity. Some people are diagnosed in the hospital or physician’s office with an ECG and some people wear a home ECG monitor for a week to diagnose their Afib.
Compared to 12 sensors, the smartwatch captures less data overall because it uses only a single sensor. This means that the results of a smartwatch may not be as reliable as those from a traditional ECG and may not pick up all types of irregular heart rhythms. A single sensor is also more prone to “noise”, meaning interference in the signal, which can affect the quality of the ECG captured. The smartwatch requires the user, not a skilled technician, to position the device correctly to ensure accurate measurements. That means the smartwatch may not capture data needed, if it is not being applied correctly. Lastly, the smartwatch is not covered by insurance, may be costly for some, and require some tech know-how to use.
What are the benefits of wearing a smartwatch for Afib?
Despite these limitations, the smartwatch does have some notable benefits:
- Smartwatches allow people with AFib to record their heart rhythm from home at any time. Although it cannot replace a traditional ECG, this ability to record your heart rhythm as symptoms occur can help provide the evidence of an arrhythmia that’s needed for meaningful conversations and treatment planning with your provider.
- Many of these smartwatches pair with apps that store data, which can be shared with your provider.
- These smartwatches don’t require a prescription or order from your cardiologist for you to use and start tracking your heart rhythm. They are also often convenient to use, water-resistant, and wireless.
- Afib can be intermittent, and sometimes it will not happen when you are at the doctor’s office. Having a device that can record the Afib outside the doctor’s office over the course of many weeks or months can provide you with the data you need for your cardiologist.
Although the data on how well smartwatches detect Afib is mixed, one recent analysis of available studies in the Journal of Atrial Fibrillation was encouraging. The conclusion was that there is no significant difference in Afib detection between smartwatches and ECG monitoring, and other types of monitoring. Unfortunately, smartwatches tended to capture many false positives too, meaning detecting the person was experiencing Afib when they were really not. As technology improves, hopefully smartwatches can be reliably used to identify both when someone is and is not experiencing Afib.
Who should I talk to if I get an Afib or abnormal rhythm notification from my smartwatch?
Talk to your primary care provider or directly to a cardiologist if you have one. Although the notification can cause anxiety, the alert may be accurate or inaccurate and only your provider can assess that with further testing.
Prepared by: Garbo Grossman, PharmD, Kelley-Ross Pharmacy Resident
References:
- American Heart Association. “What Are the Symptoms of Atrial Fibrillation (AFib or AF)?” Www.heart.org, 2016, www.heart.org/en/health-topics/atrial-fibrillation/what-are-the-symptoms-of-atrial-fibrillation-afib-or-af.
- “Atrial Fibrillation Institute Launch.” Afibinstitute.com.au, 1 June 2022, afibinstitute.com.au/atrial-fibrillation-a-guide-to-wearable-ecg-smart-watches/
- Ding, Eric Y et al. “Emerging Technologies for Identifying Atrial Fibrillation.” Circulation research vol. 127,1 (2020): 128-142. doi:10.1161/CIRCRESAHA.119.316342
- Hughes, Andrew et al. “Wearable Devices in Cardiovascular Medicine.” Circulation research vol. 132,5 (2023): 652-670. doi:10.1161/CIRCRESAHA.122.322389
- “Is Your Smartwatch Telling You That You Have Afib?” University of Iowa Health Care, 2024, uihc.org/health-topics/your-smartwatch-telling-you-you-have-afib. Accessed 28 Oct. 2024.
- Isakadze, Nino, and Seth S Martin. “How useful is the smartwatch ECG?.” Trends in cardiovascular medicine vol. 30,7 (2020): 442-448. doi:10.1016/j.tcm.2019.10.010
- Joglar, José A et al. “2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines.” Circulation vol. 149,1 (2024): e1-e156. doi:10.1161/CIR.0000000000001193
- Kamga, Paola et al. “The Use of Wearable ECG Devices in the Clinical Setting: a Review.” Current emergency and hospital medicine reports vol. 10,3 (2022): 67-72. doi:10.1007/s40138-022-00248-x
- Mehmet AE, Young D, Kanuri SH, et al. Diagnostic utility of smartwatch technology for atrial fibrillation detection – a systematic analysis. Journal of Atrial Fibrillation. Apr-May 2021. 13(6): 20200446. doi:10.4022/jafib.20200446.
