Photo by Simon Daoudi on Unsplash

ROCHESTER, Minn. — Scientists are developing a way for Apple Watches to detect people with a weak heart pump. The AI algorithm could allow for early intervention measures to prevent worsening symptoms.

Before, detecting a weak heart pump would require 12 electrodes placed around a person’s chest, arms, and legs to create a full picture of the heart’s electrical signals. But in collaboration with Anumana Inc., an AI-driven health technology company, scientists at Mayo Clinic tweaked the 12-lead algorithm for low ventricular ejection fraction into a single lead watch signal.

“Left ventricular dysfunction — a weak heart pump — afflicts 2% to 3% of people globally and up to 9% of people over age 60. It may have no symptoms, or be associated with shortness of breath, leg swelling or racing heart beats. What is important is that once we know a weak heart pump is present, there are many lifesaving and symptom-preventing treatments available. It is absolutely remarkable that AI transforms a consumer watch ECG signal into a detector of this condition, which would normally require an expensive, sophisticated imaging test, such as an echocardiogram, CT scan or MRI,” says Dr. Paul Friedman, chair of the Mayo Clinic’s Department of Cardiovascular Medicine, in a statement.

The study involved recruiting participants who downloaded an app that securely transferred ECG data from their Apple Watch in the background. Scientists used an adaptation technique to translate single-lead readings into signals that the algorithm can understand.

The algorithm recorded 125,610 ECG signals from people’s Apple Watches from over 46 states and 11 countries over six months. People commonly use the app two times a month with 92% overall participation in the app.

“Approximately 420 patients had a watch ECG recorded within 30 days of a clinically ordered echocardiogram, or ultrasound of the heart, a standard test to measure pump strength. We took advantage of those data to see whether we could identify a weak heart pump with AI analysis of the watch ECG. While our data are early, the test had an area under the curve of 0.88, meaning it is as good as or slightly better than a medical treadmill test. AI analysis of the watch ECG is a powerful test to identify a weak heart pump,” says Dr. Attia.

“The ongoing AI research in cardiology is part of Mayo’s commitment to bringing a digital transformation to health care. Advanced diagnostics that once required travel to a clinic can be accurately done, as this Apple Watch ECG study demonstrates, from a patient’s wrist whether they live in Brazil or Baton Rouge,” says Dr. Bradley Leibovich, medical director of Mayo Clinic’s Center for Digital Health ads. “App-based access to a medical center can help address health disparities by making high-level diagnostics accessible to more people in real time.”

The study was presented at the Heart Rhythm Society conference.

About Jocelyn Solis-Moreira

Jocelyn is a New York-based science journalist whose work has appeared in Discover Magazine, Health, and Live Science, among other publications. She holds a Master's of Science in Psychology with a concentration in behavioral neuroscience and a Bachelor's of Science in integrative neuroscience from Binghamton University. Jocelyn has reported on several medical and science topics ranging from coronavirus news to the latest findings in women's health.

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