Future of wearable technology in health care, with focus on atrial fibrillation detection

A person interacts with a fitness tracker, which is actively monitoring for atrial fibrillation.

Atrial Fibrillation and Its Impact

Atrial fibrillation, a common heart rhythm anomaly, often emerges after the age of 65, affecting one in three individuals throughout their lives. The risk of stroke escalates fivefold with atrial fibrillation; however, judicious use of blood thinners can reduce this risk by up to two-thirds.

The Silent Nature of Atrial Fibrillation

Interestingly, atrial fibrillation can often remain silent, influencing the heart's rhythm without noticeable symptoms. In certain cases, it manifests briefly and fades before medical attention is sought, making detection elusive. Approximately one out of every four strokes can be traced back to atrial fibrillation, a revelation often uncovered after the fact. The ability to identify covert atrial fibrillation presents a potent opportunity for stroke prevention.

Wearable Technology in Detection

Enter modern technology. The Apple Heart Study unveiled a noteworthy correlation between irregular heartbeats detected by their smartwatch and subsequent atrial fibrillation discerned via an ECG patch. Similar findings have emerged from other studies utilizing wearable technology and home ECG monitors. A novel term, "subclinical atrial fibrillation," is coined to characterize atrial fibrillation incidentally spotted by smartwatches, implanted cardiac pacemakers, or other wearable cardiac devices. Astonishingly, the ASSERT study estimates "subclinical atrial fibrillation" to be eight times more prevalent than its "clinical atrial fibrillation" counterpart.

Understanding Subclinical Atrial Fibrillation

Amidst the landscape of "subclinical atrial fibrillation," certain uncertainties linger. Stroke risk appears relatively lower (2.5-fold increased risk vs. the 5-fold risk associated with traditionally detected atrial fibrillation), prompting discussions about optimal treatment duration. For instance, fleeting episodes of atrial fibrillation lasting mere seconds are occasionally unearthed during routine pacemaker checks, yet solid data to warrant treatment for such brief occurrences is lacking. The TRENDS study suggests that atrial fibrillation should exceed 5.5 hours per day to warrant significant concern.

Who Benefits from Wearable Technology?

In a nutshell, who stands to gain the most from wearable technology for irregular heartbeat detection? In our view:

• Individuals aged 65 and above,

• Those at heightened stroke risk (with a combination of risk factors such as diabetes, high blood pressure, congestive heart failure, or prior heart attacks),

• Individuals with a history of stroke where initial investigations failed to unveil atrial fibrillation.

Additionally, those who sporadically experience palpitations or rapid heartbeats lasting longer than a few minutes, but occurring less frequently than once a month, might find value in these wearable devices. Regular, medical-grade external wearable ECGs may not be practical for extended use beyond a month.

References

TRENDS, ASSET, Apple Heart Study, e-Brave AF trials.