ArticleBMJ open2021
Manual QT interval measurement with a smartphone-operated single-lead ECG versus 12-lead ECG: a within-patient diagnostic validation study in primary care.
Article in BMJ open, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 1 of them a synthesis that pooled it.
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Who cites it
13 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Remote monitoring technologies for measuring cardiovascular functions in community-dwelling adults: a systematic review.GeroScience · 2023Pooled it
- Comparative analysis of 6-lead and single-lead consumer-grade electrocardiograms: diagnostic accuracy, numerical agreement, and inter-rater reliability.European heart journal. Digital health · 2026Article
- Beyond the QT interval: how QT/RR hysteresis may reveal a sex-dependent hidden risk for cardiac arrhythmias.American journal of physiology. Heart and circulatory physiology · 2025Article
- R-wave amplitude changes in lead aVL predict outcomes in cardiac resynchronization therapy: Exploring the role of papillary muscle dyssynchrony and mitral regurgitation.Heart rhythm O2 · 2025Article
- A smartphone application for semi-automated QT interval analysis based on a snapshot of an electrocardiogram trace displayed on a patient monitor.Journal of clinical monitoring and computing · 2025Article
- Can wearables outscore general practitioners? Congenital long QT syndrome diagnosis initiated by a smartwatch.HeartRhythm case reports · 2024Article
- Utility and acceptability of remote 6-lead electrocardiographic monitoring in children with inherited cardiac conditions.Archives of disease in childhood · 2024Article
- Use of portable single-lead electrocardiogram device as an alternative for QTc monitoring in critically ill patients.Annals of noninvasive electrocardiology : the official journal of the International Society for Holter and Noninvasive Electrocardiology, Inc · 2024Article
- Diagnostic Accuracy of Single-Lead Electrocardiograms Using the Kardia Mobile App and the Apple Watch 4: Validation Study.JMIR cardio · 2023Article
- Should all electrocardiography be ambulatory?Netherlands heart journal : monthly journal of the Netherlands Society of Cardiology and the Netherlands Heart Foundation · 2023Article
- Comparison of AliveCor KardiaMobile Six-Lead ECG with Standard ECG in Pediatric Patients.Pediatric cardiology · 2023Article
- Smart devices to measure and monitor QT intervals.Frontiers in cardiovascular medicine · 2023Review
- Comparison Between QT and Corrected QT Interval Assessment by an Apple Watch With the AccurBeat Platform and by a 12‑Lead Electrocardiogram With Manual Annotation: Prospective Observational Study.JMIR formative research · 2022Article
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9 authors.
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Abstract
objectiveTo determine the accuracy of QT measurement in a smartphone-operated, single-lead ECG (1L-ECG) device (AliveCor KardiaMobile 1L).
designCross-sectional, within-patient diagnostic validation study. SETTING/
participantsPatients underwent a 12-lead ECG (12L-ECG) for any non-acute indication in primary care, April 2017-July 2018.
interventionSimultaneous recording of 1L-ECGs and 12L-ECGs with blinded manual QT assessment. OUTCOMES OF INTEREST: (1) Difference in QT interval in milliseconds (ms) between the devices; (2) measurement agreement between the devices (excellent agreement <20 ms and clinically acceptable agreement <40 ms absolute difference); (3) sensitivity and specificity for detection of extreme QTc (short (≤340 ms) or long (≥480 ms)), on 1L-ECGs versus 12L-ECGs as reference standard. In case of significant discrepancy between lead I/II of 12L-ECGs and 1L-ECGs, we developed a correction tool by adding the difference between QT measurements of 12L-ECG and 1L-ECGs.
results250 ECGs of 125 patients were included. The mean QTc interval, using Bazett's formula (QTcB), was 393±25 ms (mean±SD) in 1L-ECGs and 392±27 ms in lead I of 12L-ECGs, a mean difference of 1±21 ms, which was not statistically different (paired t-test (p=0.51) and Bland Altman method (p=0.23)). In terms of agreement between 1L-ECGs and lead I, QTcB had excellent agreement in 66.9% and clinically acceptable agreement in 93.4% of observations. The sensitivity and specificity of detecting extreme QTc were 0% and 99.2%, respectively. The comparison of 1L-ECG QTcB with lead II of 12L-ECGs showed a significant difference (p=<0.01), but when using a correction factor (+9 ms) this difference was cancelled (paired t-test (p=0.43) or Bland Altman test (p=0.57)). Moreover, it led to improved rates of excellent (71.3%) and clinically acceptable (94.3%) agreement.
conclusionSmartphone-operated 1L-ECGs can be used to accurately measure the QTc interval compared with simultaneously obtained 12L-ECGs in a primary care population. This may provide an opportunity for monitoring the effects of potential QTc-prolonging medications.
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