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Diagnostic accuracy of a single-lead portable ECG device for measuring QTc prolongation
Charlotte L Bekker1, Fauve Noordergraaf2, Steven Teerenstra3
1Department of Pharmacy, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands.
Background:
To assess the diagnostic accuracy of a single-lead portable ECG device for measuring QTc-intervals in comparison with a standard 12-lead ECG.
Methods:
Adult patients visiting the cardiology outpatient clinic for a 12-lead recording were also measured with a portable single-lead ECG recorder (HeartcheckTM). QTc-intervals were determined by two cardiologists. Perfect agreement was defined as a limit of ≤10 ms between the two measurement methods.
Results:
Hundred one ECGs were recorded. QTc-interval mean differences between the two measurement methods was substantially outside our definition of perfect agreement (-31.9 [SD±41.3] ms).
Conclusion:
In conclusion, the Heartcheck single-lead ECG device is not accurate for measuring QTc-intervals.
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