ArticleCardiovascular digital health journal
A comparison of manual electrocardiographic interval and waveform analysis in lead 1 of 12-lead ECG and Apple Watch ECG: A validation study.
Article in Cardiovascular digital health journal. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 24 papers.
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Who cites it
24 citing papers in PubMed, 41 citations in OpenAlex.
- Multi-Tier Validation of a Single-Lead Wearable ECG Signal-Processing Pipeline: Clinical Comparison and Algorithmic Benchmarking on Public Expert-Annotated Databases.Sensors (Basel, Switzerland) · 2026Article
- The Representation of Different Populations in Studies Assessing the Validity of Consumer Wearable Photoplethysmography-Based Measurements: Scoping Review.JMIR mHealth and uHealth · 2026Article
- QTc measurement using Apple Watch electrocardiogram in congenital long QT syndrome.European heart journal. Digital health · 2026Article
- Artificial Intelligence-enhanced Electrocardiography for Heart Failure Screening and Risk Stratification.Current heart failure reports · 2026Review
- The accuracy of Apple Watch measurements: a living systematic review and meta-analysis.NPJ digital medicine · 2026Article
- Panic Attack Prediction for Patients With Panic Disorder via Machine Learning and Wearable Electrocardiography Monitoring: Model Development and Validation Study.Journal of medical Internet research · 2025Article
- Diagnostic accuracy of wearable ECG and assessment of ventricular repolarization and its cardiovascular risks post cold stress.Scientific reports · 2025Article
- Accuracy and interpretability of smartwatch electrocardiogram for early detection of atrial fibrillation: A systematic review and meta-analysis.Journal of arrhythmia · 2025Article
- Reliability and validity of a novel single-lead portable electrocardiogram device for pregnant women: a comparative study.BMC medical informatics and decision making · 2025Article
- A guide to consumer-grade wearables in cardiovascular clinical care and population health for non-experts.NPJ cardiovascular health · 2025Review
- Article
- Accuracy and clinical utility of heart rate variability derived from a wearable heart rate monitor in patients undergoing major abdominal surgery.Journal of clinical monitoring and computing · 2024Article
- Severe silent ischaemia detected with an Apple Watch in the home setting: a case report.European heart journal. Case reports · 2024Article
- Article
- Diagnostic Accuracy of Single-Lead Electrocardiograms Using the Kardia Mobile App and the Apple Watch 4: Validation Study.JMIR cardio · 2023Article
- Bioelectronic devices for light-based diagnostics and therapies.Biophysics reviews · 2023Review
- False Atrial Fibrillation Alerts from Smartwatches are Associated with Decreased Perceived Physical Well-being and Confidence in Chronic Symptoms Management.Cardiology and cardiovascular medicine · 2023Article
- Can heart rate variability data from the Apple Watch electrocardiogram quantify stress?Frontiers in public health · 2023Article
- Smart devices to measure and monitor QT intervals.Frontiers in cardiovascular medicine · 2023Review
- Assessment of Apple Watch Series 6 pulse oximetry and electrocardiograms in a pediatric population.PLOS digital health · 2022Article
Corrections and comments
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Authors and funding
6 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Background: The Apple Watch Series 4 (AW) can detect atrial fibrillation and perform a single-lead electrocardiogram (ECG), but the clinical accuracy of AW ECG waveforms compared to lead 1 of a 12-lead ECG is unclear. Objective: The purpose of this study was to assess the accuracy of interval measurements on AW ECG tracings in comparison to lead 1 on a 12-lead ECG. Methods: We obtained ECGs at a university hospital of healthy volunteers age >18 years. ECG waveforms were measured with calipers to the nearest 0.25 mm. When possible, 3 consecutive waveforms in lead 1 were measured. Waveform properties, including intervals, were recorded. Concordance correlation coefficients and Bland-Altman plots were used to assess level of agreement between devices. Results: Twelve-lead (n = 113) and AW (n = 129) ECG waveforms from 43 volunteers (mean age 31 years; 65% female) were analyzed. Sinus rhythm interpretation between devices was 100% concordant. No arrhythmias were recorded. Mean difference (d) for heart rate was 1.16 ± 4.33 bpm (r = 0.94); 3.83 ± 113.54 ms for RR interval (r = 0.79); 5.43 ± 17 ms for PR interval (r = 0.83); -6.89 ± 14.81 ms for QRS interval (r = 0.65); -11.27 ± 22.9 ms for QT interval (r = 0.79); and -11.67 ± 27 ms for QTc interval (r = 0.57). There was moderate (d <40 ms) to strong (d <20 ms or < 5 bpm) agreement between devices represented by Bland-Altman plots. Conclusion: The AW produces accurate ECGs in healthy adults with moderate to strong agreement of basic ECG intervals.
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