Investigation of QT Prolongation with Hydroxychloroquine and Azithromycin for the Treatment of COVID-19

Abstract

Objective: To assess and identify the risk of prolonged QT about hydroxychloroquine (HQ) and azithromycin (AZ) used in the treatment of patients with COVID-19.

Study design: Cohort study.

Place and duration of study: Kartal Dr. Lütfi Kırdar City Hospital, İstanbul, Turkey, from March to May 2020.

Methodology: One hundred and forty-four patients with the diagnosis of COVID-19, confirmed by Rt-PCR (reverse transcription-polymerase chain reaction), were restrospectively reviewed. Patients who were hospitalised, received HQ or HQ plus AZ treatment, had a baseline electrocardiogram (ECG), and had at least one ECG after treatment were included in the study. Patients with missing data were excluded.

Results: Fifty-one (35.4%) patients were given hydroxychloroquine monoterapy (HQ), 93 (64.6%) were given hydroxychloroquine plus azithromycin (HA), and 70 (48.6%) were women. Pre-treatment mean QTc measurements were calculated as 410.61 ± 29.44 milliseconds (ms) for HQ group and 412.02 ± 25.37 ms for HA group, while the mean values of post-treatment QTc measurements were calculated as 432.31 ± 33.97 ms for HQ group and 432.03 ± 27.0 ms for the HA group. Post-treatment QTc measurements of both HA group and HQ group were prolonged compared to pre-treatment measurements. Ventricular arrhythmia was not observed in any patient.

Conclusion: For COVID-19, no globally accepted definite treatment has yet been found. Both of hydroxychloroquine monotherapy and hydroxychloroquine plus azithromycin treatment regimens cause QTc measurement to increase at a statistically significant level. We concluded that this increase in QTc did not cause ventricular arrhythmia. Key Words: COVID-19, QTc interval, Hydroxychloroquine, Azithromycin.