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Hydroxychloroquine and Azithromycin as a Treatment of COVID-19: Electrocardiogram Variability
Amal El Ouarradi1, Salma Abdeladim1, Sara Oualim1
1Department of Cardiology, Mohammed VI University of Health Sciences, Cheikh Khalifa Hospital, Casablanca, Morocco.
Journal of the Saudi Heart Association
|December 10, 2020
Summary
The combination of hydroxychloroquine and azithromycin in COVID-19 patients can cause QT interval prolongation, a significant cardiac side effect. Close ECG monitoring is crucial, especially for high-risk individuals, to prevent severe rhythm disturbances.
Area of Science:
- Cardiology
- Infectious Diseases
- Pharmacology
Background:
- The COVID-19 pandemic spurred interest in hydroxychloroquine and azithromycin treatments.
- This combination therapy raised concerns regarding potential severe cardiac side effects.
Purpose of the Study:
- To evaluate the cardiovascular effects of combined hydroxychloroquine and azithromycin in COVID-19 patients.
- To analyze surface electrocardiogram (ECG) changes associated with this treatment regimen.
Main Methods:
- An observational cohort study involving 118 hospitalized COVID-19 patients in Morocco.
- Patients received a minimum ten-day course of hydroxychloroquine and azithromycin.
- Surface ECGs were analyzed to assess cardiac effects, focusing on QT interval prolongation.
Main Results:
- QT interval prolongation was observed in 19% of patients.
- Factors associated with QT prolongation included male gender, age over 68, cardiovascular comorbidity, high Tisdale score, and severe COVID-19.
- First-degree atrioventricular block occurred in 2 patients; no serious rhythm disorders were noted.
Conclusions:
- QT interval prolongation is a significant risk associated with the hydroxychloroquine and azithromycin combination in COVID-19 patients.
- Patient selection and close ECG monitoring are essential to identify individuals at high risk for cardiac rhythm disturbances.
- Discontinuation of treatment is advised for alarming signs like QTc prolongation (>550 ms) or ventricular arrhythmias.
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