A smart-technology wearable wristband may be able to automatically detect cardiac arrest, potentially enabling faster medical assistance and improved survival odds when cardiac arrest occurs outside of a hospital, according to new research published today in Circulation: Arrhythmia and Electrophysiology, a peer-reviewed scientific journal of the American Heart Association.
The DETECT‑1b study analyzed data from 49 adults in the Netherlands with abnormal heart rhythms who underwent a medical procedure in which a life-threatening heart rhythm was briefly induced. The algorithm-based wristband detected cardiac arrest 92% of the time, including 100% of ventricular fibrillation and 90% of pulseless ventricular tachycardia cases.
“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 the 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 examined whether a medically certified smart technology wristband that continuously monitors vital signs can detect when the heart suddenly stops pumping blood. The device uses a light-based technique (photoplethysmography algorithm) to measure changes in blood flow in the wrist.
During 125 hours of recording, 59 shockable cardiac arrest events were documented, with only nine false positives. The per-patient analysis showed 92% accuracy for detecting the irregular rhythms. “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.
In a future application, the algorithm could alert nearby lay rescuers, emergency services, or both when cardiac arrest is detected. “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, noted the low frequency of false positives as particularly impressive. “This study parallels findings from a study in Canada and one in the U.S. that shows this technology has great potential,” he said, adding that further research is needed for pulseless electrical activity, the most common presenting rhythm in cardiac arrest.
The research was conducted in a controlled clinical setting, a limitation, and the system’s effectiveness in real-world conditions still needs evaluation. The DETECT-1b study included participants with a median age of 66 years, 84% of whom were men. The broader DETECT project involves several Dutch hospitals and a company developing a smart wristband for automated cardiac arrest detection and emergency alerting.
“What is more impressive than the ability of this technology to detect cardiac arrest is the fairly low frequency of false positives it detected,” Dezfulian said. “Further research will be important.”
