B-PO04-193 BUT FOR THE BLIND SPOT: ACCURACY AND DIAGNOSTIC PERFORMANCE OF THE APPLE WATCH™ CARDIAC FEATURES IN PEDIATRIC PATIENTS

Abstract

New wearable technologies have features of ambulatory ECG monitors. The Apple Watch™ (AW) offers heart rate (HR) tracking by photoplethysmography (PPG) and single lead ECG recordings. The accuracy of HR measurements by AW and diagnostic performance of AW ECGs among children have not been explored. The primary objective was to assess the accuracy of AW HR measurements compared to gold-standard modalities (GSM) in children. Secondary objectives included differentiation of sinus from non-sinus rhythm using AW ECGs. Patients ≤18 years were prospectively enrolled to wear an AW during 1) telemetry admission, 2) electrophysiology study (EPS), or 3) exercise stress test (EST). AW HR measurements were compared to those of a GSM by intra-class correlation coefficients (ICC). AW ECGs were recorded with concurrent 12 lead ECGs and reviewed by two blinded pediatric electrophysiologists for rhythm determination. 53 patients (median age 10 years, IQR 1.2-15.0) wore AW during telemetry (48%, n=26), EPS (20%, n=11), or EST (32%, n=16). Peak HR measured by AW had high ICC to GSM, but AW were unable to record HR > 210 bpm by PPG (Table 1). 56 AW ECGs were reviewed. Excellent agreement was seen among raters (agreement 92.5%, Kappa 0.85 +/- 0 .13). Identification of non-sinus rhythm by AW ECG showed a sensitivity of 90.3-93.5% and a specificity of 95.5-96.0%. AW HR values by PPG tightly correlated with GSM measurements with the notable limitation of inability to record HR > 210 bpm. This represents a blind-spot in the application of AW for tachycardia evaluation in pediatric patients. AW ECGs had good sensitivity and specificity in identification of non-sinus rhythm.