Lessons Learned During the Pandemic: Correlation of QT Intervals Between Telemetry and 12-Lead Electrocardiogram

Area of Science:

• Cardiology
• Clinical Monitoring

Background:

• QT prolongation increases ventricular arrhythmia risk.
• Contact/droplet precautions necessitate careful monitoring for patients on QT-prolonging medications.
• Reducing staff exposure and PPE use is crucial, especially during pandemics like COVID-19.

Purpose of the Study:

• To compare QT intervals measured via telemetry versus 12-lead ECG.
• To determine if telemetry can substitute for 12-lead ECG in QT interval monitoring.

Main Methods:

• Simultaneous telemetry and 12-lead ECG recordings were obtained from 50 cardiac telemetry/ICU patients.
• QT intervals were compared between the two monitoring methods.
• Exclusion of 2 patients due to uninterpretable telemetry recordings.

Main Results:

• A high agreement (69%) was observed between telemetry and 12-lead ECG QT intervals in 48 patients.
• Intraclass correlation coefficient (ICC) was 0.887 (p<0.001), indicating strong agreement.
• Discrepancies in 31% of patients were associated with baseline rhythm, conduction, or repolarization abnormalities.

Conclusions:

• Telemetry is a viable alternative for QT interval measurement in most patients.
• Patients with baseline ECG abnormalities require serial 12-lead ECGs.
• This approach minimizes pathogen exposure and conserves PPE for isolated patients.