Smart watches to help detect arrhythmias after a stroke

One in six people will have a stroke in their lifetime. With the aging of the population, it is feared that this frequency will increase in the coming years and it is necessary to develop new strategies to improve the prevention of new cases.

A study led from the Vall d’Hebron University Hospital in Barcelona has analyzed the use of smart watches to detect atrial fibrillation early, the most common type of arrhythmia and which increases the risk of suffering a stroke up to five times.

The results show that they could be a useful complementary tool to medical care in the follow-up of hospitalized patients after a stroke to prevent it from happening again. The work has been led by Dr. Jorge Pagola, researcher of the Stroke Research group of the Vall d’Hebron Research Institute (VHIR) and associate of the Stroke Unit of the Vall d’Hebron University Hospital together with the Arrhythmia Unit and in collaboration with the Joan XXIII University Hospital and the Dr. Josep Trueta University Hospital of Girona.

The work was carried out with 70 patients from the Vall d’Hebron Hospital with an average age of 80 years and hospitalized for having recently suffered a stroke. All of them wore a Fitbit smart watch to measure their heart rate and, in addition, a continuous electrocardiogram was performed for a few hours. The aim was to compare the results obtained with both strategies when it comes to detecting atrial fibrillation, which is associated with a greater probability of suffering a stroke and, furthermore, with a more severe and disabling stroke. “The watches represent a simple to use, low-cost, non-invasive and well-accepted strategy, which could be useful for monitoring patients, also in elderly people”, explains Dr. Claudia Meza, a member of the Unit of Stroke at Vall d’Hebron Hospital and researcher of the VHIR Stroke Research group.

On the one hand, the heart rate was measured in hospitalized patients, and it was observed that the watch had a tendency to give values ​​that were lower than the real ones, especially when they were higher than 100 beats per minute or when there was an episode of arrhythmia. In this sense, it is thought that the changes in the skin and blood circulation present in advanced age may alter the measurement and, therefore, in these patients watches would not be recommended to control heart rate.

On the other hand, the watch alerts that appear when it detects that there is an irregular heart rhythm, suggestive of atrial fibrillation, were analyzed. Thus, it was found that the watch was capable of detecting 34.5% of real cases with this arrhythmia with a specificity of 100%. In other words, it detected a third of the cases, but all those it detected actually had atrial fibrillation according to the electrocardiogram.

Atrial fibrillation alert on a smart watch. (Photo: Vall d’Hebron University Hospital)

The results of the study indicate that smartwatches can help to monitor some stroke patients in the long term, especially those with intermittent episodes of arrhythmias and no clear associated symptoms, which can be difficult to detect if not followed. does continuous monitoring. “It is important to highlight that they must be a tool that helps the usual diagnostic methods to detect arrhythmias. In no case should they replace regular medical care, since we must then confirm the results obtained and adjust the treatment accordingly if necessary to prevent subsequent strokes”, emphasizes Dr. Jorge Pagola.

In the future, more research is needed to evaluate the effectiveness of these methods in clinical practice, both in younger people and in non-hospitalized patients going about their usual lives. In addition, it is expected that the continuous technological development will also increase the sensitivity to detect a higher percentage of cases.

The study is titled “Accuracy of a Smartwatch to Assess Heart Rate Monitoring and Atrial Fibrillation in Stroke Patients”. And it has been published in the academic journal Sensors. (Source: Vall d’Hebron University Hospital)