IL6 and Bradycardia: IL-6 combined with AZM and HCQ (0.5-time CRD) or HCQ (1-time CRD) or HCQ (2-time CRD) caused further significant and dose-dependent bradycardia, PR, QRS and QTc prolongations, and complete atrioventricular dissociation (Fig. 1c–i and Table 1A).