Research Highlights:

  • A five-year, randomized controlled trial of 60 counties in North Carolina (representing a population of over 8.5 million people) found that a comprehensive emergency medical services (EMS) and community-based cardiac arrest educational intervention did not significantly improve survival to hospital discharge with good brain function for adults who experienced cardiac arrest outside of a hospital.
  • The trial of the RACE-CARS intervention program did not improve overall rates of bystander CPR or defibrillation for people who experienced out-of-hospital cardiac arrest.
  • Notably, an exploratory analysis found that during the final year of the study, people who experienced out-of-hospital cardiac arrest in communities with the education program had 33% higher odds of receiving bystander CPR than those in communities that were not part of the intervention program, showing that longer-term community CPR education initiatives appear to improve bystander response and warrant further study.
  • Note: This trial is simultaneously published today as a full manuscript in the peer-reviewed scientific journal NEJM.

Embargoed until 4:15 p.m. CT/5:15 p.m. ET, Sunday, November 8, 2026

This news release contains updated information provided by the researchers and not listed in the abstract.

CHICAGO, IL - November 8, 2026 (NEWMEDIAWIRE) - A comprehensive EMS and community-based educational intervention in North Carolina focused on recognizing out-of-hospital cardiac arrest and actions needed quickly to increase bystander CPR and use of an automated external defibrillator (AED) did not significantly improve patient survival with favorable brain function, according to new, independent, preliminary, late-breaking science presented today at the American Heart Association’s Scientific Sessions 2026. The meeting, on Nov. 6-9 in Chicago, is a premier global exchange of the latest scientific advancements, research and evidence-based clinical practice updates in cardiovascular science.

“Your chance of survival while waiting for emergency medical services during a cardiac arrest decreases by 10% every minute without CPR,” said study author Carolina Malta Hansen, M.D., Ph.D., a cardiologist and clinical research associate professor at Herlev and Gentofte Hospital and Copenhagen EMS in Denmark. “The RACE-CARS trial was an ambitious effort to improve cardiac arrest outcomes across entire communities, including rural areas where emergency care often relies on volunteer-first responders.”

The five-year trial included 60 counties in North Carolina that were randomly assigned to receive the cardiac arrest educational intervention or continue their existing cardiac arrest response practices. Researchers implemented a series of efforts aimed to improve early care and outcomes for people who experienced out-of-hospital cardiac arrest. The intervention program included community-wide CPR education and training, and an EMS component that included training 9-1-1 dispatchers to quickly recognize cardiac arrest and guide callers through CPR, as well as enhanced first-responder efforts, including increased use of defibrillation before EMS arrival. The training was free and incorporated into schools, workplaces, county government and other community organizations.

What are the study’s key findings?

  • Cardiac arrests: Over the five-year study period, 11,615 people experienced out-of-hospital cardiac arrest in communities that received the educational intervention, and 10,844 people had cardiac arrest outside of a hospital in communities that did not receive the intervention.
  • Survival: About 9% of patients who experienced out-of-hospital cardiac arrest in communities that were part of the intervention program survived to leave the hospital with favorable brain function, compared with 9.4% in communities that were not part of the intervention program.
  • Bystander CPR: Bystanders performed CPR in 44.8% of cardiac arrests in communities that received the educational intervention, compared with 42.3% in communities that did not. Notably: during the last year of the study, people who experienced out-of-hospital cardiac arrest in communities that were part of the program had 33% higher odds of receiving CPR from a bystander than those in communities that were not.
  • Early defibrillation: Defibrillation occurred before emergency medical services (EMS) arrived in 13.5% of cardiac arrests in communities that received the educational intervention, compared with 15.3% of the communities in the study that did not. Of the 31 counties that received a total of 405 trial-provided defibrillators, 26 counties (87%) deployed the devices; 19 (63%) placed defibrillators in publicly accessible locations; and 18 (60%) deployed defibrillators with first responders, including fire departments and law-enforcement agencies.
  • Community participation: Community partners conducted 5,724 CPR training events, reaching 201,586 people, or 4.8% of residents in communities that were included in the educational intervention. Participation in the CPR training programs varied considerably, with four counties reaching more than 10% of residents and eight reaching fewer than 3%. Most counties also established systematic training of employees at workplaces such as county government, schools and large businesses.

Christopher Granger, M.D., FAHA, the trial principal investigator and a cardiologist and professor at Duke University in North Carolina, said, “The increase in bystander CPR toward the end of the study shows there was some effect and suggests that a sustained community outreach may be needed to show an improvement in survival. We have established an efficient, high-quality clinical trial network to continue this work.” 

“Changing how an entire community responds to cardiac arrest takes time, and our findings show just how challenging that can be. In the meantime, the message to the public remains simple: learn CPR, recognize the signs of cardiac arrest, call 9-1-1 immediately and follow the dispatcher’s instructions. Everyone has the potential to save a life,” said Hansen.

According to the American Heart Association’s 2026 Heart Disease and Stroke Statistics, approximately 350,000 people in the U.S. experience cardiac arrest outside a hospital each year, and only about 1 in 10 survive. Immediate CPR can double or triple a person’s chance of survival. The Association’s comprehensive 2025 Guideline for CPR and emergency cardiovascular care emphasizes the importance of quickly recognizing cardiac arrest, calling 9-1-1, starting CPR and using an AED, a portable device that can help to restore a normal heart rhythm by delivering an electric shock through the chest, when available. However, only about 40% of people who experience out-of-hospital cardiac arrest receive bystander CPR, and only 10% have an AED applied by a bystander before emergency medical services (EMS) arrives, according to the Heart Association’s AED Fact Sheet.

What are the study’s details, background, design and limitations?

  • The study was conducted from July 1, 2021, through June 30, 2026, in 60 counties throughout North Carolina, including urban and rural communities. The counties represented approximately 8.5 million residents, or nearly 80% of the state’s population.
  • Researchers randomly assigned 31 of the counties to receive a comprehensive, community-based cardiac arrest response education program. The other 29 counties continued their own efforts and response to cardiac arrest without the education program from the RACE-CARS team.
  • The study included 22,459 adults ages 18 and older who experienced cardiac arrest outside of a hospital in all 60 counties over the five-year study period. The median age of cardiac arrest patients was 64 years; 37% were women, 33% were Black adults, and 29% lived in rural areas. Researchers excluded cardiac arrests witnessed by EMS personnel or occurring in hospitals, nursing homes or other healthcare facilities.
  • Researchers used the Cardiac Arrest Registry to Enhance Survival (CARES), a national database that includes data from 9-1-1, EMS and hospitals, to collect data and to evaluate whether patients survived to leave the hospital with favorable brain function, whether bystanders performed CPR and whether defibrillation occurred before EMS arrived. Local leaders, such as county commissioners and church leaders, were recruited to promote community efforts. Surveys were completed every six months to report on community CPR training, AED deployment and other aspects of how the education program was implemented.
  • Study limitations included differences in how extensively counties implemented the intervention program and reliance on self-reported information to assess 9-1-1 training, CPR training and first responder engagement. Staffing shortages and turnover at 9-1-1 centers created challenges for training and data collection. The COVID-19 pandemic and Hurricane Helene, which severely affected western North Carolina, also created operational challenges for the program.

A key strength of the study was its size, inclusiveness of the entire eligible population and the inclusion of both urban and rural communities, allowing researchers to evaluate the program across a broad range of typical emergency response settings. Hansen also emphasized the value of collaboration among local governments, community organizations, 9-1-1 centers and first responders. She stressed that CPR education should be widely accessible through schools, workplaces and other community settings, and that strong first-responder programs are especially important in rural areas where EMS response times may be longer. Researchers suggested that reaching more people with CPR education and sustaining these efforts over time may be necessary to achieve changes in community response that could improve survival.
Through its Nation of Lifesavers initiative, the American Heart Association aims to double survival rates from sudden cardiac arrest by 2030 by expanding CPR education and training and helping more people recognize and respond to cardiac emergencies. The Nation of Lifesavers movement has already increased U.S. bystander CPR confidence from 33% to 39% since it launched in 2023, representing 17.7 million more people ready to act in a cardiac emergency.

Co-authors and disclosures are listed in the abstract. The study was funded by the National Institutes of Health and National Heart, Lung, and Blood Institute, a division of the National Institutes of Health.

Statements and conclusions of studies that are presented at the American Heart Association’s scientific meetings are solely those of the study authors and do not necessarily reflect the Association’s policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. Abstracts presented at the Association’s scientific meetings are not peer-reviewed, rather, they are curated by independent review panels and are considered based on the potential to add to the diversity of scientific issues and views discussed at the meeting. The findings are considered preliminary until published as a full manuscript in a peer-reviewed scientific journal.

The Association receives more than 85% of its revenue from sources other than corporations. These sources include contributions from individuals, foundations and estates, as well as investment earnings and revenue from the sale of our educational materials. Corporations (including pharmaceutical, device manufacturers and other companies) also make donations to the Association. The Association has strict policies to prevent any donations from influencing its science content and policy positions. Overall financial information is available here.

Additional Resources:

###

About the American Heart Association

The American Heart Association is a relentless force for a world of longer, healthier lives. Dedicated to ensuring equitable health in all communities, the organization has been a leading source of health information for more than one hundred years. Supported by more than 35 million volunteers globally, we fund groundbreaking research, advocate for the public’s health, and provide critical resources to save and improve lives affected by cardiovascular disease and stroke. By driving breakthroughs and implementing proven solutions in science, policy, and care, we work tirelessly to advance health and transform lives every day. Connect with us on heart.org, Facebook, X or by calling 1-800-AHA-USA1.

For Media Inquiries and American Heart Association Expert Perspective:

American Heart Association Communications & Media Relations in Dallas: 214-706-1173; ahacommunications@heart.org

Amanda Ebert: Amanda.Ebert@heart.org

For Public Inquiries: 1-800-AHA-USA1 (242-8721)

heart.org and stroke.org