Arrhythmia is a common health issue leading to pediatric cardiology referrals and presents unique diagnostic challenges in children. Traditional methods including patch rhythm monitors and Holter monitors, often fall short due to their limited duration, discomfort, and sporadic nature of symptoms. Implantable loop recorders offer a longer-term solution but require an invasive procedure. The Apple Watch, a popular adult arrhythmia detection tool, has shown potential in pediatric applications. Its dual capabilities of passive heart rate alerts and patient-initiated ECG recordings make it a promising tool for extended heart rhythm monitoring in children. Challenges arise due to children’s higher heart rates and activity levels, and the lack of arrhythmia detection algorithms tailored for pediatric use.
A study at Lucille Packard Children’s Hospital Stanford retrospectively analyzed patients under 18 years who exhibited arrhythmia signs captured by an Apple Watch, leading to a formal diagnosis. This approach overcomes the limitations of traditional ambulatory cardiac monitors, which often fail to detect arrhythmias due to short wear times and skin irritation. The analysis includes Apple Watch data submitted by patients or caregivers, focusing on its role in arrhythmia diagnosis, results from other cardiac monitoring studies, and findings from invasive electrophysiology studies. The study’s design adhered to ethical standards, with Stanford University’s Institutional Review Board waiving the need for guardian consent. The study identified 145 cases where the Apple Watch played a role in arrhythmia detection, confirming arrhythmias in 41 patients. These patients, with an average age of 13.8 years, presented various arrhythmias including supraventricular tachycardia (SVT), ventricular tachycardia (VT), heart block, and wide complex tachycardia. In 71% of these cases, Apple Watch findings led to a new arrhythmia diagnosis. As well as this, in 35 patients who also used traditional ambulatory monitors, 10 did not detect arrhythmias captured by the Apple Watch. This portrays the Apple Watch’s utility in scenarios where conventional monitors fall short.
The Apple Watch proved beneficial in both diagnosing new arrhythmia cases, and also in monitoring known cases. Patients with a history of successful SVT ablations used the device for symptom tracking, leading to the identification of SVT recurrences. The study also detailed potential drawbacks, such as the false-positive rate of device-generated alerts. About 25% of patients without arrhythmia sought medical care based on Apple Watch notifications, indicating a need for more precise algorithms tailored for pediatric patients. The findings demonstrate that the Apple Watch can record adverse arrhythmia events in children, filling a gap left by traditional monitoring methods. This is particularly relevant for patients with congenital heart disease, where the Apple Watch effectively captured arrhythmias in several cases. Examples include a patient with repaired Tetralogy of Fallot and another who had undergone an orthotopic heart transplant, both of whom had arrhythmias confirmed by the device.
This study contributes to the growing body of evidence supporting the use of wearable devices in pediatric cardiology. It shows the Apple Watch’s potential as a non-invasive, extended cardiac monitoring tool for children, complementing traditional diagnostic methods. Limitations exist due to the retrospective nature of the study and potential selection bias, as the patient cohort came from a large referral center. The study did not fully assess the false-positive rates or the accuracy of the Apple Watch in comparison to gold-standard ambulatory methods. Despite these limitations, the study is a positive step towards future research, including prospective studies comparing the Apple Watch with traditional monitors to better understand its diagnostic value in children.