A smartphone app that alerts nearby CPR-trained volunteers did not increase the likelihood that a person experiencing cardiac arrest received CPR or an AED before professional responders arrived, according to preliminary late-breaking research presented at the American Heart Association's Resuscitation Science Symposium 2026. The study, conducted in British Columbia and Columbus, Ohio, randomly assigned cardiac arrest 911 calls to either standard EMS dispatch alone or standard dispatch plus PulsePoint Respond alerts to nearby volunteers.
Among 355 people in the primary analysis, bystander CPR or AED use occurred in 69% of cases when PulsePoint alerts were activated and 72% with standard 911 response alone—a difference that was not statistically significant. Bystander CPR rates were 70% and 73%, respectively, while bystander AED use was 15% and 17%. Survival to hospital discharge was about 21% in both groups. Median time from 911 call to EMS arrival was 5.6 minutes in the alert group and 5.9 minutes in the no-alert group.
The findings matter because out-of-hospital cardiac arrest is a time-critical emergency where every minute without CPR reduces survival chances. PulsePoint Respond connects with local 911 dispatch centers to send "CPR Needed" notifications to nearby app users who indicate they are willing to perform CPR, displaying the emergency location and nearby AEDs. EMS agencies pay a subscription fee, but the app is free for community volunteers.
"In the event of a cardiac arrest, calling 911 is essential, yet even a rapid professional response can take several minutes—time the person in cardiac arrest cannot afford to lose," said Steven Brooks, M.D., M.H.Sc., senior lead author and professor at Queen's University in Kingston, Ontario. "We found that bystander CPR was already common without alerts in the regions we studied. In the control group, 73% of patients received bystander CPR. This unexpectedly high rate may have limited the opportunity for alerted responders to provide additional benefit."
Researchers reviewed 17,547 randomly assigned 911 calls for possible cardiac arrest in public locations from June 8, 2021, to March 27, 2026. Most arrests occurred in urban settings (91%). In 57% of activated incidents, only one app user was within 400 meters, and 91% had four or fewer volunteer responders nearby. The study does not answer whether benefits would differ for cardiac arrests in private homes, rural areas, or communities with denser volunteer networks—questions researchers say remain important for future research.
The results could influence how EMS agencies and policymakers evaluate investments in volunteer alerting systems. "Although our study didn't show the PulsePoint smartphone alerts increasing bystander CPR and AED use in public locations, it will contribute evidence to help the global resuscitation community, emergency medical services and policymakers assess the potential of this approach," Brooks said. The abstract is available via the Link to abstract, with further details in the Online Program Planner and the meeting's About Resuscitation Science Symposium 2026 page.
As abstracts presented at scientific meetings are not peer-reviewed, the findings are considered preliminary until published in a peer-reviewed journal. The American Heart Association notes that statements and conclusions of studies presented at its meetings are solely those of the authors. Financial information is available here. For those inspired to act, the Association offers resources to Join the Nation of Lifesavers by learning CPR today, and its 2025 American Heart Association Guidelines for CPR and ECC provide current guidance.
