Apple Heart Study – Clinical Trial Review

Apple Heart Study – Clinical Trial Review

The Apple Heart Study was designed as a large-scale, app-based study to identify cardiac arrhythmias using a smartwatch [1]. Pulse rate can be measured using smartwatch and fitness band wearable consumer electronic devices by photoplethysmography. Pulse irregularity from these data can potentially identify atrial fibrillation.

Participants without self reported atrial fibrillation used a smartwatch (Apple iPhone) app to consent to monitoring. If possible atrial fibrillation was detected by the smartwatch algorithm, a telemedicine visit was initiated and an ECG patch was mailed to the participant. Patches were worn for 7 days. Surveys were conducted 90 days after notification of the irregular pulse and at the end of the study period.

The study recruited more than 400 thousand participants over a period of 8 months. At a median 117 days of monitoring 2161 participants received notification of irregular pulse. 450 participants returned ECG patches containing data which could be analyzed. Patches were applied on an average 13 days after notification. Overall 34% had atrial fibrillation. Percentage in those aged 65 years or more was 35% [2].

Positive predictive value was 0.84 among participants who were notified of an irregular pulse for observing atrial fibrillation on the ECG simultaneously with a subsequent irregular pulse notification. This was a unique siteless study in that no on-site visits were required for the participants. Authors concluded that the pragmatic study design provides a foundation for  future large-scale studies in which outcomes or adherence can be reliably assessed with user-owned devices.

References

1. Turakhia MP, Desai M, Hedlin H, Rajmane A, Talati N, Ferris T, Desai S, Nag D, Patel M, Kowey P, Rumsfeld JS, Russo AM, Hills MT, Granger CB, Mahaffey KW, Perez MV. Rationale and design of a large-scale, app-based study to identify cardiac arrhythmias using a smartwatch: The Apple Heart Study. Am Heart J. 2019 Jan;207:66-75. doi: 10.1016/j.ahj.2018.09.002. Epub 2018 Sep 8. PMID: 30392584; PMCID: PMC8099048.
2. Perez MV, Mahaffey KW, Hedlin H, Rumsfeld JS, Garcia A, Ferris T, Balasubramanian V, Russo AM, Rajmane A, Cheung L, Hung G, Lee J, Kowey P, Talati N, Nag D, Gummidipundi SE, Beatty A, Hills MT, Desai S, Granger CB, Desai M, Turakhia MP; Apple Heart Study Investigators. Large-Scale Assessment of a Smartwatch to Identify Atrial Fibrillation. N Engl J Med. 2019 Nov 14;381(20):1909-1917. doi: 10.1056/NEJMoa1901183. PMID: 31722151; PMCID: PMC8112605.