Assessment of QT Intervals in a Case Series of Patients With Coronavirus Disease 2019 (COVID-19) Infection Treated With Hydroxychloroquine Alone or in Combination With Azithromycin in an Intensive Care Unit
Study of 40 very serious condition ICU patients, 75% required invasive mechanical ventilation, 63% received vasoactive drugs, 50% received other treatments favoring QT prolongation. HCQ with or w/o AZ was given to 45% and 55% respectively. They showed an increase in QTc, more significant with the combination of HCQ+AZ where prolonged QTc was observed in 36% (10 with ΔQTc >60 milliseconds and 7 with QTc ≥500 milliseconds). No ventricular arrhythmia, including torsades de pointes, was recorded. While these results may not be generalizable outside the ICU, caution is recommended in use, especially with the combination.
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 HCQ (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 hydroxychloroquine 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 hydroxychloroquine and azithromycin together."
Bessière et al., 1 May 2020, peer-reviewed, 7 authors.
Initial Experience Prescribing Commercial Tafamidis, the Most Expensive Cardiac Medication in History
MD, MS Ahmad Masri, PharmD Hongya Chen, MD Catherine Wong, MSN, RN Katherine L Fischer, MD Chafic Karam, MD, MPH Walid F Gellad, MD Stephen B Heitner
JAMA Cardiology, doi:10.1001/jamacardio.2020.1738
program, a specialty pharmacy, and a dedicated pharmacist who spent an average of 1 hour per patient to ensure they can afford tafamidis. As such, our experience might not be easily applicable to other health care settings.
