QTc prolongation and mortality in SARS-2-CoV-infected patients treated with azithromycin and hydroxychloroquine.

This study points out that combination therapy of hydroxychloroquine with azithromycin (HY+AZ) prolongs the QT interval in COVID-19 patients. Interestingly, patients who reached a QTc of at least 500 ms, a cut-off value known to increase the arrhythmic risk independently of comorbidity, among those treated with HY+AZ, have a significant prolonged QTc interval at the admission ECG compared with those who did not reach this QTc value despite the same treatment. This last finding suggests a potential higher arrhythmic risk in patients with QTc slightly prolonged at hospital admission who are treated with HY+AZ, stressing the need to perform careful ECG monitoring in these patients.