Could your smartwatch spot a heart problem? What to know about wearables and AFib

Smartwatches and other wearables can do an amazing number of things, including potentially alerting you to a common heart condition called atrial fibrillation (AFib).

AFib is an electrical disorder of the heart and a type of abnormal heart rhythm in which the heart’s upper chambers beat irregularly and out of sync with the heart’s lower chambers. An estimated 5 million Americans have AFib, making it one of the most common types of heart rhythm conditions.

Some people with AFib don’t notice any symptoms, but it commonly feels like heart palpitations or a fluttering feeling in the chest. AFib can also cause shortness of breath, fatigue, lightheadedness or dizziness.

“While smartwatches alone can’t diagnose AFib, they can alert us to symptoms that might have otherwise gone unnoticed,” said Sahil Attawala, MD, a cardiac electrophysiologist with Endeavor Health.

How do smartwatches detect AFib?

While doctors confirm AFib with an electrocardiogram, smart watches often use photoplethysmography (PPG), which measures changes in blood flow using light.

How accurate are watches at detecting AFib?

Interestingly, some devices can detect AFib fairly accurately. One study of the Apple Watch found it correctly detected AFib 84% of the time, while a study of Fitbit found the device was correctly detecting AFib 98.2% of the time.

That said, a wearable device is not a definitive diagnosis, nor is it necessarily accurate for you. If you feel symptoms and get a notification from your smartwatch, your next step should be to schedule a visit with your primary care physician.

Can you rely on a watch to provide critical health data?

Nobody should rely on a smartwatch to diagnose a disease. But these devices could make it easier for you and your physician to analyze and treat your health.

“They could be especially helpful for people at a higher risk of developing AFib —people who are older than 65, have high blood pressure or heart disease, or who have chronic health conditions such as lung disease or diabetes,” Dr. Attawala said.

While smartwatches may not be consistently accurate, they do track your health data over time, which can be useful for your physician to see. This can be true of AFib in particular, as sometimes people don’t feel the symptoms.