Electrocardiographic safety of daily Hydroxychloroquine 400mg plus Azithromycin 250mg as an ambulatory treatment for COVID-19 patients in Cameroon

Objective To determine the early electrocardiographic changes in a cohort of ambulatory cameroonian COVID-19 patients treated with hydroxychloroquine and Azithromycin. Design Prospective study. Setting Treatment centres of the city of Yaounde, Cameroon, from May 7th to 24th 2020. Participants We enrolled 51 consecutive confirmed COVID-19 on RT-PCR who having mild forms of COVID-19 and treated by hydroxychloroquine 200mg twice daily during seven days plus Azithromycin 500 mg the first day and 250 mg the remaining 4 days as per national standard. Main outcomes measures The primary end-point was the change in QTc interval between day 0 (D0), day 3 (D3) and day 7 (D7). Secondary endpoints were changes in all other cardiac electrical conductivity patterns and the occurrence of clinical arrhythmic events during the course of treatment. Results The population (29 men and 22 women) was aged 39 ± 11 years (range 17 to 61 years). Mean Tisdale score was 3.35±0.48. No significant change from baseline (D0) of QTc was observed at D7 (429±27 ms at D0 versus 396±26 ms at D7; p=0.27). A reduction of heart rate was observed between the D0 and D7 (75±13 bpm versus 70±13 bpm, p = 0.02) with increased QRS duration between D0 and D7 (95±10 ms versus 102±17 ms, p = 0.004). No symptomatic arrhythmic events occurred during the treatment course. Conclusions No life-threatening modifications of the QT interval was observed in non-severe COVID-19 patients treated ambulatory with hydroxychloroquine and azithromycin. Studies are needed in critical-ill and older patients.