A new 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, potentially enabling faster medical assistance and improving survival odds for the hundreds of thousands of people who experience out-of-hospital cardiac arrest each year.
The DETECT-1b study analyzed data from 49 adults in the Netherlands with abnormal heart rhythms who underwent a routine medical procedure in which a life-threatening heart rhythm was briefly induced. The researchers tested a wristband that uses a light-based technique, known as photoplethysmography, to continuously monitor blood flow changes at the wrist. The algorithm detected cardiac arrest in 92% of cases, including 100% of ventricular fibrillation episodes and 90% of pulseless ventricular tachycardia events.
“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 in Nijmegen, Netherlands. “With the device automatically notifying emergency services or nearby trained responders, help could arrive sooner, which may significantly improve survival chances.”
The study recorded 59 shockable cardiac arrest events, defined as rhythms that can be corrected by an automated external defibrillator (AED). The wristband accurately identified cardiac arrest in 92% of these events. There were nine false positives during 125 hours of recording, a rate that researchers consider promising for a detection device.
“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,” said lead study author Roos Edgar, M.Sc., a technical physician at Radboud University Medical Center. While many commercially available smartwatches use similar sensors, most are not designed to detect cardiac arrest, she noted.
Cameron Dezfulian, M.D., FAHA, chair of the American Heart Association’s Resuscitation Science Symposium Program Committee, who was not involved in the study, praised the low false-positive rate. “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 said. “This study parallels findings from a study in Canada and one in the U.S. that shows this technology has great potential.”
However, Dezfulian noted that pulseless electrical activity, the most common presenting rhythm in cardiac arrest, accounts for only a small number of validation data points for such sensors, and further research is needed. Bonnes acknowledged that the study was conducted in a controlled clinical setting, a limitation that requires future evaluation of the system’s effectiveness and reliability in real-world conditions.
The research is part of the broader DETECT project, a collaboration of several hospitals and a company in the Netherlands working to develop a smart wristband for automated cardiac arrest detection and emergency alerting. The goal is to eventually connect the wristband to emergency dispatch centers and volunteer responder networks, allowing immediate alerts when cardiac arrest is detected.
