“Several cardiology societies have also highlighted the cardiac considerations for using these drugs in patients with Covid-19, including a summary coauthored by the presidents of the American College of Cardiology, the American Heart Association, and the Heart Rhythm Society. The authors stressed that “hydroxychloroquine and azithromycin have been touted for potential prophylaxis or treatment for Covid-19; both drugs are listed as definite causes of torsades de pointes” and increase in the risk of other arrhythmia and sudden death.
from Cardiology News, “FDA limits use of hydrochloroquine for Covid-19 to hospitals, trials” by Mitchel L. Zoler from the FDA
(Circulation. 2020 Apl 8. doi 10.1161/CIRCULATIONAHA.120.047521)