Wearables and the Electrophysiology Practice: Challenges and Opportunities

Editor's Note: Listen to EP Lab Digest's podcast discussion with Dr. Tarakji — link is included at the end of this article!  

Digital technologies have transformed all aspects of life, including shopping, banking, streaming music and movies, booking travel, and more. This digital transformation has reshaped many traditional industries, including healthcare delivery, and has mainly been the result of a wide availability of smart devices and Internet connectivity among the general public. In regard to healthcare, this transformation has also been aided by a flood of new healthcare apps and wearables. The premise of this transformation is to provide better patient care at a lower cost through enhanced patient engagement. However, despite the hype about digital health, adoption in healthcare has been slow. Often, use of digital technology is limited to utilization of electronic medical records and easy access to digital medical literature.  

There are multiple reasons behind the slower adoption of digital technologies in healthcare. Some of these reasons stem from the unique nature of healthcare as an industry, and others are due to the solutions proposed. Many digital health products lack essential needs assessment.

Some startups also release minimum viable products to the public without proper testing or validation. Theranos is one example, and has become the poster child of failure in gaining the trust of the healthcare system.¹ It promised the ability to provide a battery of blood values through tiny drops of blood, offering a cheaper and more efficient alternative to traditional medical laboratory testing. This turned out to be a fraudulent claim that was later revealed, but only after the company had collected billions of dollars of investment money without proper independent validation study. The evolution of digital health technology has also outpaced physicians’ ability to adapt. Confusion about the stakeholders in the design of these products has led many healthcare providers to find themselves on the receiving end without any knowledge or involvement in the process of development. In addition, this transformation is coming at a time when physician burnout is widely recognized as a national crisis, and healthcare providers are not sensing the promised benefits of using these digital solutions in creating more efficient workflows.² In fact, examples of using wearables in clinical practice have occasionally dwarfed into models of concierge medicine rather than widespread public health solutions. While banks, travel agencies, and the music industry have smoothly transitioned their operations into digital ones, physician practices must ensure patient care irrespective of technology access, social status, or age. Lastly, with the model of direct-to-consumer products, startup and technology companies are releasing products (sometimes with FDA clearance) without addressing the regulatory issues of workflow, processing, storage, or billing. There is also a lack of understanding of the complexity of the healthcare system, leaving healthcare providers feeling alone in tackling these logistical issues and with little incentive to use these technologies. 

Cardiac electrophysiology remains at the forefront of digital health. This is partly due to the fact that for decades, digital technologies have been an essential part of our practice with cardiac implantable electronic devices (CIEDs), remote monitoring, and medical-grade cardiac rhythm monitoring devices. It is also the result of a more recent abundance of direct-to-consumer devices that have the ability to check pulse irregularities or record an ECG tracing. In general, consumer products detect arrhythmias through two main mechanisms. For example, photoplethysmographic (PPG) sensors provide constant pulse monitoring; however, they lack the electrical signature usually needed to establish a reliable diagnosis of arrhythmia. The other mechanism is a mobile ECG device (Figure 1), which enables the user to record a rhythm strip on demand. These devices provide the electrical signature needed, but lack the ability to continuously monitor pulse or rhythm.^3,4 The development of smartwatches has enabled the coupling of both technologies, which has allowed for passive assessment of pulse rate and regularity with on-demand ECG confirmation, including when the PPG algorithm for atrial fibrillation (AF) detection is triggered through different formulas (Figure 2).⁵ The recording can then be downloaded or shared with the physician. 

Using artificial intelligence embedded in the software of these products allows for automated interpretation that can provide instant diagnosis of possible AF. These automated algorithms have been tested through several independent studies. A common theme among available ECG wearables is that they perform the task of recording a rhythm strip equivalent to traditional single-lead monitors. However, while the automated algorithms for AF detection are very advanced, false negatives and positives can sometimes occur. For any recording to trigger a change in patient management, physician overread is still needed. Despite these shortcomings, it is important to note that many of these validation studies compared the recordings and automated interpretation of wearables to standard 12-lead ECGs. Also, when interpreting the performance data of these devices, one has to remember that the user is an important element of the process. Noisy or short recordings can lead to misinterpretation. While this might not be a fair comparison, seeking perfection is understandable since these devices are available to the public, and false positive results can lead to raising anxiety or more additional unnecessary testing. In addition to the fact that these ECG recordings are subject to interpretation, even when confirmed, there is no clear guidance on how to manage randomly detected, short-lived episodes of AF. This issue should not be viewed as a failure of the technology, but rather as a gap in our clinical knowledge that ongoing studies can hopefully fill — wearables can help the medical community answer some of these unanswered questions.

In the Apple Heart study that enrolled nearly 420,000 Apple Watch users, 0.5% of users received an irregular heart rhythm notification.⁶ Among these, 34% had documented AF on subsequent ECG patch readings. In patients who received a notification while wearing an ECG patch, the positive predictive value for the notification was 84% in detecting AF. However, it is important to note that 16% of users who received the notification were 22 to 39 years old, and only 33% of those who received the notification had a CHA₂DS₂-VASc score of 2 or greater. This raises the question about optimal management of these notifications among low-risk individuals. 

From a clinical practice standpoint, wearables that record ECGs can be a great asset, especially among AF patients. AF is the most common arrhythmia in the world, and its prevalence and incidence are increasing. Management of the AF patient involves multiple stages starting with establishing a diagnosis, using rate or rhythm control strategies (both medically or through interventions, including cardioversion or ablation), and preventing stroke using anticoagulation when indicated. The ability to record ECG on demand can help facilitate all of these stages. 

Establishing a diagnosis in a patient who complains of intermittent, infrequent episodes of palpitation can be challenging — many of these patients go through multiple types of monitors or have several emergency visits before confirming the diagnosis of their arrhythmia. Wearables with the ability to record an ECG rhythm strip on demand could be very helpful in providing documentation of the rhythm at the time of symptoms. These devices can also help with management of patients who have already been diagnosed with AF, including monitoring for recurrence after a cardioversion or ablation procedure, or assessing response to antiarrhythmic drug therapy. In addition, smartphone ECG monitors enable us to explore the possibility of transforming the concept of a “pill in the pocket” approach from the use of an antiarrhythmic drug on demand to the use of anticoagulation as needed, especially in the era of the short-acting DOACs,^7,8 a concept that will need to be validated through randomized clinical trials. Finally, wearables can be very useful when utilizing telemedicine. With the proper tools and data collected from smartphone ECG recordings over an extended period of time (versus a single ECG), a virtual visit has the potential to be more informative and helpful than an in-person visit. 

From research standpoint, digital technology is reshaping the way we conduct clinical research. Pragmatic studies, direct-to-participant studies, siteless trials, e-consent, and virtual follow-up are all part of the new vocabulary in conducting clinical trials. These novel studies are also moving from observational studies looking into AF detection among high-risk individuals (mSToPS study),⁹ to detecting AF in the general public (Apple Heart study and MAFA II study),^6,10 to looking into outcomes from these wearables through ongoing and future studies (Heartline study: www.heartline.com).¹¹ 

We are certainly living in a new era of healthcare delivery as well as witnessing a new partnership between the patient and physician. Digital health should not be a burden, but rather an asset to provide better care. Releasing innovative devices to the market is a step forward, but in order to achieve true impact, these devices need to be coupled with proper testing and validation, easy workflows to embed them into clinical practice, clear rules and regulations for proper use, and reimbursement models. Progress has been made in all of these aspects, albeit at different paces. Understanding these devices and their potential values is an important investment in caring not only for the patients of today, but certainly for the patients of tomorrow. 

Disclosures: Dr. Tarakji reports personal fees (consulting/advisory board) from Medtronic and AliveCor, and personal fees (consulting) from Boston Scientific.

1. Ioannidis JPA. Stealth research and Theranos: reflections and update 1 year later. JAMA. 2016;316:389-390.
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10. Guo Y, Wang H, Zhang H, et al, MAFA II investigators. Mobile photoplethysmographic technology to detect atrial fibrillation. J Am Coll Cardiol. 2019;74:2365-2375.
11. A Study to Investigate if Early Atrial Fibrillation (AF) Diagnosis Reduces Risk of Events Like Stroke in the Real-World. ClinicalTrials.gov. Available at https://bit.ly/2ZcVEeD. Accessed May 26, 2020.