Finding the best screening method for a common heart condition, with the goal of preventing stroke

Early detection of atrial fibrillation can help significantly reduce the risk of stroke, and digital health tools may be the answer.

September 30, 2020

LA JOLLA, CA—Scientists at Scripps Research Translational Institute have demonstrated a promising new model for using digital health wearables to identify people with atrial fibrillation before they exhibit symptoms.

The screening approach could be expanded to save lives, as atrial fibrillation increases a person’s risk of having a stroke by fivefold. If the condition is found early, preventative treatments nearly eliminate that risk.

The study appears in EP Europace, a journal published by the European Heart Rhythm Association of the European Society of Cardiology.

Atrial fibrillation—often referred to as afib—is the most common heart rhythm problem in the world, affecting more than 6 million adults in the United States alone. Yet too often, the condition goes undetected until after a stroke, says Giorgio Quer, PhD, who led the study.

Patients are traditionally not screened for atrial fibrillation. If they are screened, it’s typically done “opportunistically,” during a visit with a healthcare provider for another reason, by feeling the individual’s pulse or taking a 10-second electrocardiogram (ECG) reading. For that reason, roughly 20 percent of people are first identified as having the condition at the time of their stroke. However, modern digital health tools enable much easier and more affordable heart monitoring outside of the clinic.

“Screening for atrial fibrillation is possible today using one of many technologies that can accurately measure heart activity, including smartwatches, smartphones, patches, implantable devices and more,” says Quer, director of Artificial Intelligence at Scripps Research Translational Institute. “In this study, we explored how to use tools like these to best identify people with asymptomatic atrial fibrillation, with the ultimate goal of reducing stroke.” 

The Scripps Research team previously showed that by monitoring at-risk individuals continuously for several weeks using an ECG patch technology, they found atrial fibrillation among 6.4 percent of the participants, who were asymptomatic.

But since other studies screening for atrial fibrillation have relied on obtaining a 30-second ECG “snapshot” one or more times a day for several weeks, the new study was designed to create a model to enable researchers and healthcare systems to design better screening programs to more accurately identify individuals who have the condition and are most likely to benefit from preventative treatment.

The team dug into data from their prior studies, looking at the continuous heart monitoring data of nearly 7,000 individuals with intermittent atrial fibrillation. Using this information, they simulated the likelihood of being able to identify atrial fibrillation in an individual by capturing just 30-second ECG recordings several times a day for multiple days, and what the characteristics of the atrial fibrillation (for example, the length of time that people experienced the condition) would likely be present in the individuals identified by that method.

They found that while the intermittent screening approach caught only approximately half of all the people with atrial fibrillation that a continuous patch identified, the individuals it identified as having the condition had a much higher disease burden, meaning they spent a larger percentage of time with irregular heartbeat.

“There is still a lot to learn about how to best screen people for atrial fibrillation in a way that will most effectively prevent strokes and all of its complications, including death,” says Steven Steinhubl, MD, director of Digital Medicine at Scripps Research Translational Institute. “As the digital tools available to physicians and to all people continues to expand, we believe this work empowers providers, systems and individuals to create an early detection program for atrial fibrillation that best meets their needs.”

As a next step, Quer said the intermittent screening approach should be tested with different devices and monitoring characteristics, then adopted and validated as part of larger prospective trials.

The study, “Screening for Atrial Fibrillation: Predicted Sensitivity of Short, Intermittent ECG Recordings in an Asymptomatic At-Risk Population,” is authored by Giorgio Quer and Steven R. Steinhubl of Scripps Research and Ben Freedman of the Heart Research Institute and the Charles Perkins Centre at University of Sydney.

The work was supported in part by the National Center for Advancing Translational Sciences (NCATS), which was established to transform the translational process so that new treatments and cures for disease can be delivered to patients faster.

For more information, contact press@scripps.edu See More News