Monitoring for individual triggers may reduce episodes of atrial fibrillation

Research Highlights:

  • Personalized testing may help identify triggers for irregular heart rhythms and reduce their frequency in people with atrial fibrillation.
  • Alcohol consumption was linked to having an atrial fibrillation episode.
  • Caffeine did not appear to increase the risk for an episode of atrial fibrillation.

Embargoed until 2:19 p.m. CT/3:19 p.m. ET, Sunday, Nov. 14, 2021

(NewMediaWire) – November 14, 2021 – DALLAS – People with atrial fibrillation who underwent individualized testing to discover triggers for their irregular heartbeats reported less frequent irregular episodes, according to late-breaking research presented today at the American Heart Association’s Scientific Sessions 2021. The meeting is fully virtual, Saturday, November 13-Monday, November 15, 2021, and is a premier global exchange of the latest scientific advancements, research and evidence-based clinical practice updates in cardiovascular science for health care worldwide.

Atrial fibrillation (AFib) is an irregular or quivering heartbeat that can lead to blood clots, stroke, heart failure and other heart-related complications. At least 2.7 million Americans live with this condition in which the upper chambers of the heart, the atria, beat irregularly (quiver), which can lead to the formation of blood clots. Left untreated, AFib doubles the risk of heart-related death and increases stroke risk 5-fold. People with AFib report that certain behaviors appear to increase the likelihood of an AFib episode. In the I-STOP-AF Trial, “Individualized Studies of Triggers of Atrial Fibrillation: A Randomized Controlled Trial,” researchers set out to determine whether monitoring potential triggers could reduce AFib episodes.

“There has been little research done on whether perceived triggers of AFib actually lead to AFib episodes,” says Gregory Marcus, M.D., M.A.S., the study’s lead author, a professor of medicine at the University of California, San Francisco School of Medicine and associate chief of cardiology for research at UCSF Health. “Our research team aimed to determine whether perceived triggers equate to actual triggers – and whether tracking triggers for AFib could lead to fewer episodes.”

Researchers initially enrolled 446 participants in the trial, with 320 completing the study. They performed a remote, mobile application-based trial, and patients were randomly assigned to either monitor their AFib episodes without tracking their presumed triggers, or to test whether specific “triggers” affected or caused atrial fibrillation episodes. The comparison took place over a 10-week period, with both groups of patients using a specific device to monitor or track AFib triggers.

Participants who tested specific AFib triggers could select from a menu of triggers – or write in a personalized trigger at the start of the study. The testing group then received instructions to either expose themselves or to avoid a specific trigger (alcohol, caffeine, less sleep, etc.) during a given week. This process was randomized over a six-week period, and all participants reported daily about any atrial fibrillation episodes.

At the conclusion of the first six weeks of the trial, participants received their results on the probability that their presumed trigger did or did not influence the chance of experiencing an AFib episode. All participants were then given the option to continue to test potential AFib triggers. Those who had been tracking AFib episodes could now also test a specific trigger for an individualized study. At the end of week 10 of the trial, both groups completed a questionnaire about the severity of their atrial fibrillation.

The study’s findings include:

  • Patients who completed the individualized trigger study reported less frequent episodes of atrial fibrillation during the four weeks after their testing compared to those who only tracked AFib episodes.
  • Drinking alcohol was associated with more atrial fibrillation episodes than when patients avoided that trigger.
  • In contrast, caffeine consumption was not linked to an increased risk of AFib episodes.

“As this was the first study to tackle this idea, there are many lessons we have learned that future studies could build upon,” said Marcus. “We also had a unique opportunity to work closely with patients who have atrial fibrillation including several atrial fibrillation patients who are now co-authors of the study. It’s important for us, as health care professionals, to focus on patient-centered outcomes.”

Marcus says these findings point to the need for more real-time assessments, such as those available to the study participants who had access to daily, text-based surveys. The research team also believes assessments of possible AFib triggers can empower patients by alerting them to behaviors they can change in their daily lives.

Several limitations were noted for the study. First, all study participants did not complete all assessments, particularly for the daily, smartphone-based ECG monitoring. The study relied on self-reported responses to determine compliance with AFib trigger testing assignments. Additionally, because the study was dependent on participants use of their own smartphones, the findings may not be generalizable to patients without access to these devices. 

Co-authors are Madelaine Faulkner Modrow, M.P.H.; Christopher H. Schmid, Ph.D.; Kathi Sigona, M.A.; Gregory Nah, M.A.; Jiabei Yang, M.S.; Tzu-Chun Chu, M.P.H.; Sean Joyce, B.S.; Shiffen Gettabecha, M.P.H.; Kelsey Ogomori; Vivian Yang; Xochitl Butcher; Mellanie True Hills, B.S.; Debbe McCall, M.B.A.; Kathleen Sciarappa, Ed.D.; Ida Sim, M.D., Ph.D.; Mark J. Pletcher, M.D., M.P.H.; and Jeffrey E. Olgin, M.D. Authors’ disclosures are listed in the abstract.

The study was funded by the Patient Outcomes Research Center.

Additional Resources:

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. The Association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific Association programs and events. The Association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and biotech companies, device manufacturers and health insurance providers and the Association’s overall financial information are available here.

The American Heart Association’s Scientific Sessions 2021 is a premier global exchange of the latest scientific advancements, research and evidence-based clinical practice updates in cardiovascular science for health care professionals worldwide. The 3-day meeting will feature more than 500 sessions focused on breakthrough cardiovascular basic, clinical and population science updates in a fully virtual experience Saturday, November 13 through Monday, November 15, 2021. Thousands of leading physicians, scientists, cardiologists, advanced practice nurses and allied health care professionals from around the world will convene virtually to participate in basic, clinical and population science presentations, discussions and curricula that can shape the future of cardiovascular science and medicine, including prevention and quality improvement. During the three-day meeting, attendees receive exclusive access to more than 4,000 original research presentations and can earn Continuing Medical Education (CME), Continuing Education (CE) or Maintenance of Certification (MOC) credits for educational sessions. Engage in Scientific Sessions 2021 on social media via #AHA21.

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