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Published on: December 11, 2019
Portable single-lead electrocardiogram device is accurate for QTc evaluation in hospitalized patients
María Mónica Marín O1, Ángel Alberto García P1, Oscar Mauricio Muñoz V2
1Department of Cardiology, Pontificia Universidad Javeriana, Hospital Universitario San Ignacio, Bogotá, Colombia.
Insights
Portable ECG devices accurately measure QTc intervals, showing excellent agreement with traditional 12-lead ECGs. This offers a simpler alternative for assessing QTc prolongation in hospitalized patients, especially during the COVID-19 pandemic.
Area of Science:
- Cardiology
- Medical Devices
- Public Health
Background:
- Common medications and COVID-19 can prolong the QTc interval, increasing arrhythmia risk.
- Accurate QTc interval monitoring is crucial for patient safety.
Purpose of the Study:
- To compare the accuracy of a portable single-lead ECG device (KardiaMobile) with a standard 12-lead ECG for QTc interval measurement.
- To evaluate the clinical agreement and precision of the portable ECG device.
Main Methods:
- 128 COVID-19 patients' ECGs were recorded using both KardiaMobile and a 12-lead ECG.
- Bland-Altman plots and Lin's concordance coefficient assessed QTc interval agreement.
- Kappa statistics evaluated consistency in identifying QTc prolongation.
Main Results:
- KardiaMobile and 12-lead ECG showed similar QTc intervals (442.45 ± 40.5 vs 441.65 ± 40.3 ms).
- Bland-Altman analysis revealed no significant difference, with excellent agreement (Lin's CC = 0.988).
- Both devices demonstrated excellent concordance in detecting QTc prolongation (kappa >0.90).
Conclusions:
- The KardiaMobile device provides accurate QTc interval assessment.
- Its ease of use offers advantages over conventional ECG for hospitalized patients.
- This portable ECG is a viable alternative for QTc evaluation, particularly during the COVID-19 pandemic.
Background:
Many commonly used drugs can prolong the QTc interval (QTc), which can lead to potentially life-threatening arrhythmias. In the current era of the COVID-19 pandemic, it is worth mentioning that the disease itself and several drugs used for its treatment have been associated with QTc prolongation.
Objective:
To evaluate the agreement and clinical precision of a portable single-lead electrocardiogram (ECG) device to measure the QTc interval compared to the standard 12-lead ECG.
Methods:
In sequential tests, QTc of ECG recordings obtained with the KardiaMobile (KM-1L) device (AliveCor, San Francisco, CA) were compared to QTc obtained with conventional 12-lead ECG. Agreement was evaluated using Bland-Altman plots and Lin's concordance coefficient. Consistency between the 2 devices in determining QTc prolongation (QTc ≥470 ms in males or ≥480 ms in females) was evaluated with kappa statistics.
Results:
A total of 128 patients with a presumed or confirmed diagnosis of COVID-19 admitted to a university hospital were included. QTc intervals measured with KM-1L were similar to QTc measured with conventional ECG (442.45 ± 40.5 vs 441.65 ± 40.3 ms, P = .15). Bland-Altman analysis showed no significant difference in QTc values (average difference of -0.797, 95% limits of agreement:-13.179; 11.585). Lin's concordance coefficient showed an excellent agreement (0.988, P < .001). Concordance between the 2 devices for determining QTc prolongation was excellent (kappa >0.90).
Conclusion:
ECG recordings obtained with KM-1L allow an accurate QTc interval assessment. Considering its simplicity of use, this approach has advantages over conventional ECG and can provide an alternative for the evaluation of QTc in hospitalized patients, during the current time of the COVID-19 pandemic and beyond.
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