Antiarrhythmic agents
HCLQ, a derivative of chloroquine, is notoriously known for drug-induced QT prolongation.35,40,41,42Moreover, azithromycin also induces QT prolongation.35 The administration of antiarrhythmic agents, including amiodarone, dronedarone, flecainide and propafenone with HCLQ or azithromycin may further increase the risk of QT prolongation and induce ventricular tachyarrhythmia or sudden cardiac death (Table 1). Therefore, ECG monitoring for the QT interval is important. Drugs should be either withheld or removed if QT interval is longer than 500ms as generally recommended. The increased plasma level of antiarrhythmic agents while being used with these antiviral drugs would potentially increase the risk of malignant arrhythmias and sudden cardiac death.
In addition to ventricular tachyarrhythmia, co-administration of antiarrhythmic agents and investigational COVID-19 medications could increase the blood concentration of class Ic and class III antiarrhythmic drugs, and expose the patients to risk of atrial proarrhythmic events. The increased blood concentration of class Ic and III antiarrhythmic agents, including propafenone and amiodarone, would change conduction properties of the atrial tissue. For example, persistent atrial flutter may occur with the increase of atrial refractory period.43,44,45