et al., JAMA Cardiol., May 1, 2020, doi:10.1001/jamacardio.2020.1834 (Peer Reviewed) (not included in the study count)
Study of 90 hospitalized patients given HC
Q, 53 also receiving AZ, 53% hypertension, 29% diabetes mellitus, baseline median QTc 473ms for HC
Q, and 442ms for HC
Q+AZ. Median change for HC
Q+AZ ΔQTc of 23ms vs. 5.5ms for HC
Q. Other factors such as stress cardiomyopathy or myocarditis could not be ruled out. Without a control arm, they could not conclude that HC
Q and AZ conferred increased cardiotoxic risk; however, compared with HC
Q alone, ΔQTc differences were likely associated with the addition of AZ. The likelihood of prolonged QTc was greater in those who received concomitant loop diuretics or had a baseline QTc of 450 milliseconds or more. HC
Q was discontinued in 10 patients due to adverse events including nausea, hypoglycemia, and 1 case of torsades de pointes. There were no deaths reported.
Appropriate use and careful analysis of contraindications, risks, and benefits are important. More recent and much larger studies have not shown significant safety concerns, including outpatient RCTs showing no serious adverse events, and even the RECOVERY trial which used an unusually high dose of HC
Q (including 237 patients also receiving AZ) reports they "did not show any excess in ventricular tachycardia (including torsade de pointes) or ventricular fibrillation in the hydroxych
loroquine arm", and "serious cardiovascular toxicity has been reported very rarely despite the high prevalence of cardiovascular disease in hospitalized patients, the common occurrence of myocarditis in COVID-19, and the extensive use of hydroxych
loroquine and azithromycin together."