Comparison of recordings obtained with smart watches and standard 12 lead ECG devices in pediatric patients with congenital heart disease

Objective: The use of wearable technology in healthcare is becoming increasingly widespread; however, the reliability of these devices in monitoring children with congenital heart disease remains unclear. Therefore, determining the accuracy and reliability of smartwatch electrocardiography (ECG) measurements compared to conventional methods is of great significance. This study aims to evaluate the diagnostic accuracy and reliability of single-lead ECG recordings obtained from smartwatches compared to standard 12-lead ECGs in pediatric patients diagnosed with congenital heart disease (CHD). Materials and Methods: This prospective, single-center study was conducted at the Department of Pediatric Cardiology, Çukurova University Faculty of Medicine, between January 1, 2023, and December 23, 2023. The study included pediatric patients aged 0–18 years who had been diagnosed with CHD and were under follow-up. Written informed consent was obtained from the parents of all participants, and both standard 12-lead ECG and single-lead ECG recordings via smartwatches were obtained. Standard 12-lead ECG recordings were performed using the Schiller AT 102 Cardiovit device. Smartwatch ECG recordings were obtained from Apple Watch Series 8 and Samsung Galaxy Watch 5, capturing D1, D2, and D3 leads. The measured electrocardiographic parameters included heart rate, P wave duration, PR interval, QRS duration, QT and QTc intervals, ST segment duration, and T wave duration. QTc calculations were performed using Bazett's formula. Statistical analyses were conducted using IBM SPSS Statistics 27.0 (IBM Corp., Armonk, NY, USA). Results: A total of 109 patients were included in the study. When comparing single-lead ECG recordings from smartwatches with standard 12-lead ECGs, a strong correlation was observed in heart rate (r=0.92, p<0.001), PR interval (r=0.88, p<0.001), and QRS duration (r=0.81, p=0.002). Particularly, a significant agreement in heart rate measurements was found between Apple Watch Series 8 and Samsung Galaxy Watch 5 compared to standard ECG (Apple Watch: 78.5±12.3 bpm, Standard ECG: 79.1±11.8 bpm, p=0.87). However, statistically significant differences were found between smartwatches and standard ECG in QT duration (Apple Watch: 398.2±24.6 ms, Standard ECG: 412.9±22.1 ms, p=0.032) and QTc duration (Apple Watch: 422.3±27.8 ms, Standard ECG: 438.6±25.3 ms, p=0.041). Additionally, T wave amplitude was found to be lower in smartwatch recordings, with a statistically significant difference between the two methods (p=0.018). Conclusion: This study demonstrates that smartwatches can accurately measure heart rate and some fundamental electrocardiographic parameters in children with CHD. However, significant differences in critical measurements such as QT and QTc intervals indicate that smartwatches may not yet be fully reliable alternatives for clinical follow-up. Further studies are needed to confirm their clinical applicability. With advancements in wearable technology, these devices may become more widely used in cardiological assessments in the future. Keywords: Congenital heart disease, electrocardiography, smartwatch, wearable technology, pediatric cardiology.