Health Smartwatches can help detect cardiac arrhythmia
According to a study, smartwatches can detect cardiac arrhythmias more frequently than conventional standard medical care. This was announced by the Amsterdam University Medical Center (UMC) in the analysis published in the "Journal of the American College of Cardiology".
23.01.2026, 04:58
SDA
The study focused on atrial fibrillation, the most common cardiac arrhythmia worldwide. It often occurs irregularly and many sufferers are unaware of it. The research team led by cardiologist Michiel Winter and doctoral student Nicole van Steijn investigated whether wearable devices such as a smartwatch can help to detect such disorders earlier and more reliably than previous methods.
In atrial fibrillation, the atria of the heart beat irregularly. This can lead to blood clots - small clumps of clotted blood - forming in the heart. "If these clots travel to the brain, they can cause a stroke," said Winter. As the fibrillation often only occurs intermittently ("paroxysmal") or the patient has no symptoms ("asymptomatic"), it often goes undetected during routine examinations by the doctor.
The team used smartwatches for the study, which involved a total of 437 patients over the age of 65 with an increased risk of stroke. Half of the participants wore them for at least twelve hours a day for six months, while the other half received standard medical care without digital monitoring.
Optical pulse measurement and ECG function
Two functions of the smartwatch were used: the optical pulse measurement PPG (photoplethysmography) and a simple ECG (electrocardiogram) to record the electrical heart currents. While the pulse measurement only allows the irregularities to be suspected, the ECG is necessary to medically confirm the diagnosis of atrial fibrillation. Smartwatches from several manufacturers offer these functions.
Atrial fibrillation was detected four times more frequently in the group with smartwatches than in the control group. Specifically, 21 patients with smartwatches were diagnosed and treated for the condition. In the control group without a watch, there were five. In the group without a watch, all five patients had symptoms, so they went to the doctor because they felt unwell. In the smartwatch group, around half of the patients (57 percent) were asymptomatic - they had no symptoms and would probably not have known that their heart was out of sync without the watch.
The limits of the technology
The technology did not prove to be infallible in the study. Nicole van Steijn explained in an interview with dpa that there were false alarms. Of the 72 patients for whom the watch was triggered, only around half actually had atrial fibrillation.
Study leader Winter said that against the backdrop of an increasingly overburdened healthcare system, such wearable devices made it possible to medically monitor large populations without the need for constant hospitalization. "We expect that we will definitely see fewer strokes due to atrial fibrillation if we study on a large scale in this way, as we can treat patients at a very early stage of their disease," Winter said.
