Smart watches for heart rate assessment in atrial arrhythmias.

Abstract

Despite studies demonstrating the accuracy of smart watches (SW) and wearable heart rate (HR) monitors in sinus rhythm, no data exists regarding their utility in arrhythmias. 102 hospitalized patients were evaluated at rest using continuous electrocardiogram (ECG) monitoring with concomitant SW-HR (FitBit, FB, Apple Watch, AW) for 30 min. Across all devices, 38,616 HR values were recorded. Sinus rhythm cohort demonstrated strong agreement for both devices with a low bias (FB & AW Bias = 1 beat). In atrial arrhythmias, AW demonstrated a stronger correlation than FB (AW rs = 0.83, FB rs = 0.56, both p < 0.01) with a lower bias (Bias AW = -5 beats, FB = -18 beats). Atrial flutter demonstrated strongest agreement in both devices with a mean bias <1 beat. However, in AF, there was significant HR underestimation (Bias FB = -28 beats, AW-8 beats) with wide limits of agreement. Despite HR underestimation in AF, when SW recorded HR ≥ 100 in arrhythmias, 98% of values were within ±10-beats of ECG-HR. SW demonstrate strong agreement for HR estimation in sinus rhythm and atrial flutter but underestimates HR in AF. Tachycardic episodes recorded at rest on a SW may be suggestive of an underlying atrial tachyarrhythmia and warrant further clinical evaluation. Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) ACTRN: 12616001374459.