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Hydroxychloroquine/Azithromycin Therapy and QT Prolongation in Hospitalized Patients With COVID-19
Thomas F O'Connell1, Christopher J Bradley1, Amr E Abbas1
1Department of Cardiovascular Medicine, Oakland University William Beaumont School of Medicine and Beaumont Hospital, Royal Oak, Michigan, USA.
JACC. Clinical Electrophysiology
|January 22, 2021
Summary
Hydroxychloroquine and azithromycin (HCQ/AZM) treatment for COVID-19 caused corrected QT (QTc) prolongation in hospitalized patients. Factors like age and heart failure influenced QTc prolongation, but it did not increase mortality risk.
Area of Science:
- Cardiology
- Infectious Diseases
- Pharmacology
Background:
- Hydroxychloroquine and azithromycin (HCQ/AZM) combination therapy was widely used for COVID-19.
- Concerns existed regarding HCQ/AZM's potential for QT interval prolongation and arrhythmogenesis in COVID-19 patients.
Purpose of the Study:
- To characterize corrected QT (QTc) prolongation in hospitalized COVID-19 patients treated with HCQ/AZM.
- To identify factors associated with QTc prolongation and assess its impact on mortality and arrhythmias.
Main Methods:
- Retrospective cohort study of 415 hospitalized COVID-19 patients receiving HCQ/AZM.
- QTc interval measured before and up to 5 days after drug initiation.
- Primary endpoint: magnitude of QTc prolongation; Secondary endpoints: ventricular arrhythmias and all-cause mortality.
Main Results:
- Mean QTc increased from 443 ms to 473 ms; 21% of patients had QTc ≥500 ms.
- Factors associated with QTc prolongation ≥500 ms included older age, lower BMI, heart failure, elevated creatinine, and peak troponin.
- No significant association between QTc change and mortality (HR: 0.998; p=0.607).
Conclusions:
- Hospitalized COVID-19 patients treated with HCQ/AZM experienced QTc prolongation.
- Specific clinical factors correlated with increased QTc prolongation.
- QTc prolongation was not linked to increased mortality in this cohort.
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