Conclusion
HCQ use in COVID-19 may cause a significant proportion of critical QTc
prolongation. In our study population, DM and concomitant oseltamivir
use were found to raise the incidence of critical QTc prolongation but
none of our patients suffered from TdP, ventricular arrhythmia and
sudden cardiac arrest. Because of the nature of COVID-19, the use of
concurrent drugs and the clinical situations that have potential to
enhance QTc interval should be kept in mind while using HCQ and special
attention should be paid for ECG monitoring.