Smart Wristband May Detect Cardiac Arrest, Study Finds

A small study published today in Circulation: Arrhythmia and Electrophysiology, a peer-reviewed journal of the American Heart Association, suggests that a smart technology wristband may be able to automatically detect cardiac arrest. The DETECT-1b study, conducted in the Netherlands, analyzed data from 49 adults with abnormal heart rhythms who underwent a medical procedure in which pulseless ventricular tachycardia (pVT) or ventricular fibrillation (VF) was briefly induced.

The algorithm-based wristband detected cardiac arrest 92% of the time, including 100% of ventricular fibrillation cases and 90% of pulseless ventricular tachycardia cases, with only nine false positives during over 125 hours of recording. “Our findings are important because many out-of-hospital cardiac arrests are unwitnessed. A smart technology wristband capable of automatically detecting cardiac arrest and triggering an alert could function as a digital witness,” said study senior author Judith Bonnes, M.D., Ph.D., a cardiologist at Radboud University Medical Center.

The device uses a photoplethysmography algorithm to continuously monitor blood flow changes in the wrist, differing from previous approaches by allowing unobtrusive daily monitoring. Lead study author Roos Edgar, M.Sc., a technical physician at Radboud University Medical Center, noted, “This is the first study to externally validate such an algorithm using patient data, which is an important step toward developing a reliable detection system for real-world use.”

While many commercially available smart watches use similar sensors, most are not designed to detect cardiac arrest. The research is part of the broader DETECT project, a collaboration of several hospitals and a company in the Netherlands, aiming to develop a smart wristband that automatically detects cardiac arrest and alerts emergency services.

In a future application, the algorithm could alert nearby lay rescuers and emergency dispatchers. “The goal is to connect the wristband to emergency dispatch centers and volunteer responder networks in the Netherlands so that nearby rescuers and ambulance services can be alerted immediately when cardiac arrest is detected,” Bonnes said.

Cameron Dezfulian, M.D., FAHA, chair of the American Heart Association’s Resuscitation Science Symposium Program Committee, who was not involved in the study, commented, “What is more impressive than the ability of this technology to detect cardiac arrest is the fairly low frequency of false positives it detected.” He added that pulseless electrical activity remains the most common presenting rhythm in cardiac arrest and accounts for a small number of validation data for such sensors, emphasizing the need for further research.

The study was conducted in a controlled clinical setting, which is a limitation. The system’s effectiveness and reliability in real-world conditions still need to be evaluated. Participants had a median age of 66 years, and 84% were men. Researchers assessed more than 125 hours of algorithm data for cardiac arrest alerts.

For more information, visit the American Heart Association’s cardiac arrest resources and view the manuscript online.