Meeting NewsPerspective

Smartwatch heart rate sensor capable of detecting atrial fibrillation

CHICAGO — According to a study presented at the Heart Rhythm Society Annual Scientific Sessions, the heart rate sensor of the Apple Watch can detect symptomless atrial fibrillation when paired with artificial intelligence.

Using photoplethysmography, smartwatches can detect heart rate and potentially provide a way to detect silent AF, the researchers wrote in an abstract.

The researchers used the smartwatch’s photoplethysmographic sensors in combination with a deep learning algorithm to determine if AF could be detected using heart rate data.

Gregory M. Marcus

The study enrolled patients with AF without a ventricular paced rhythm who were undergoing cardioversion.

According to the release, data from 6,158 users of Cardiogram for Apple Watch were used to develop a “deep neural network” algorithm to distinguish AF from sinus rhythm.

“One of the major advantages of this approach is that it leverages devices that individuals are purchasing on their own and wearing continuously anyway,” Jose Sanchez, MD, cardiac electrophysiology fellow at University of California, San Francisco, told Cardiology Today.

Sanchez, Marcus and colleagues validated the algorithm in a cohort of 51 patients with AF scheduled to undergo cardioversion. Each of the 51 patients (mean age, 66 years; 68% men; 61% white; 54% with normal left ventricular function) who underwent successful cardioversion wore an Apple Watch 20 minutes before and 20 minutes after cardioversion; performance of the deep learning algorithm was compared with that of a 12-lead ECG.

Compared to previously validated algorithms for AF, the C-statistic for AF detection using the deep learning algorithm was significantly higher (0.97), as was the sensitivity of 98.04% and the specificity of 90.2%, the researchers reported.

“While mobile technology screening won’t replace more conventional monitoring methods, it has the potential to successfully screen those at an increased risk and lower the number of undiagnosed cases of AF,” Marcus said in the release. – by Dave Quaile

Reference:

Sanchez JM, et al. AF detection and ablation outcomes: Answering questions that matter to patients. Presented at: Heart Rhythm Society Annual Scientific Sessions; May 10-13, 2017; Chicago.

Disclosure: Marcus reports receiving research grants from Cardiogram Inc. Sanchez reports no relevant financial disclosures.

CHICAGO — According to a study presented at the Heart Rhythm Society Annual Scientific Sessions, the heart rate sensor of the Apple Watch can detect symptomless atrial fibrillation when paired with artificial intelligence.

Using photoplethysmography, smartwatches can detect heart rate and potentially provide a way to detect silent AF, the researchers wrote in an abstract.

The researchers used the smartwatch’s photoplethysmographic sensors in combination with a deep learning algorithm to determine if AF could be detected using heart rate data.

“Our results show that common wearable trackers like smartwatches present a novel opportunity to monitor, capture and prompt medical therapy for AF without any active effort from patients,” Gregory M. Marcus, MD, MAS, endowed professor of atrial fibrillation research and director of clinical research for the division of cardiology at University of California, San Francisco, said in a press release.

Gregory M. Marcus

The study enrolled patients with AF without a ventricular paced rhythm who were undergoing cardioversion.

According to the release, data from 6,158 users of Cardiogram for Apple Watch were used to develop a “deep neural network” algorithm to distinguish AF from sinus rhythm.

“One of the major advantages of this approach is that it leverages devices that individuals are purchasing on their own and wearing continuously anyway,” Jose Sanchez, MD, cardiac electrophysiology fellow at University of California, San Francisco, told Cardiology Today.

Sanchez, Marcus and colleagues validated the algorithm in a cohort of 51 patients with AF scheduled to undergo cardioversion. Each of the 51 patients (mean age, 66 years; 68% men; 61% white; 54% with normal left ventricular function) who underwent successful cardioversion wore an Apple Watch 20 minutes before and 20 minutes after cardioversion; performance of the deep learning algorithm was compared with that of a 12-lead ECG.

Compared to previously validated algorithms for AF, the C-statistic for AF detection using the deep learning algorithm was significantly higher (0.97), as was the sensitivity of 98.04% and the specificity of 90.2%, the researchers reported.

“While mobile technology screening won’t replace more conventional monitoring methods, it has the potential to successfully screen those at an increased risk and lower the number of undiagnosed cases of AF,” Marcus said in the release. – by Dave Quaile

Reference:

Sanchez JM, et al. AF detection and ablation outcomes: Answering questions that matter to patients. Presented at: Heart Rhythm Society Annual Scientific Sessions; May 10-13, 2017; Chicago.

Disclosure: Marcus reports receiving research grants from Cardiogram Inc. Sanchez reports no relevant financial disclosures.

    Perspective
    John Higgins

    John P. Higgins

    Just as the mobile phone has become a supercomputer internet companion, the digital watch appears to be transforming into a digital doctor that can track and monitor your body system.

    Already, the activity, heart rate, and accelerometer provide a wealth of information for driving behavioral change and exercise progression, but what about detecting signs of illness?

    Detecting abnormal heart rates and rhythms in patients is a common task for physicians, who often use a selection of expensive accessories such as Holter monitors, event records, and implantable loop recorders to figure it out.  What if I told you that your smartwatch might screen with no effort or cost on your part? It appears that for AF, the Apple Watch may accurately detect this, which is a big deal as AF is the most common cause of stroke.  

    This new study uses software and hardware, Cardiogram for Apple Watch app and the smartwatch’s photoplethysmographic sensors in combination with a deep learning algorithm respectively, to accurately detect atrial fibrillation in 51 patients with AF undergoing cardioversion.    

    The beauty is that this “watch’ is on your wrist most of the time, and thus could accrue important information about your heart rate and rhythm. Having this information can not only warn you of the risk for a possible future stroke, but also of an impending MI.

    And with newer 4G watches arriving, this might mean that your provider or the nearest emergency facility could be notified in real time with your rhythm strip, and if the heart rate or rhythm is significantly abnormal and/or life threatening, the watch could instruct you to seek medical advice, or dispatch EMS to your GPS-determined location. And you may even be able to FaceTime your physician in an instant so they can triage you appropriately.  With such technology, science fiction is becoming our new reality.

    What other sensors is the Apple Watch primed for? A blood oxygen meter to measure the oxygen saturation of your blood, blood glucose monitors to track diabetics, blood count to detect anemia, and full vital signs. Consider a fully loaded watch with medical, health, wellness, fitness sensors, devices and applications — this may help prevent, diagnose, and manage disease, as well as monitor recovery in the user. This could ultimately be an extension of your medical record and history, providing your physician with an accurate history of abnormal body system function, as well as monitoring treatment and recovery.  Stay tuned.

    They say the eyes are the window to the soul. Perhaps in the future, your electronic watch will be the window to your health.

    • John P. Higgins, MD, MBA
    • Associate Professor of Medicine
      The McGovern Medical School at UTHealth, Houston
      Sports Cardiologist, Rice University Athletics and the Houston Rockets

    Disclosures: Higgins reports no relevant financial disclosures.

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