IL6 and COVID-19: In fact, the hypothesis that IL-6 plays a key role in the pathogenesis of COVID-19-associated QTc prolongation, as suggested by the evidence that in these patients a correlation between IL-6 levels and QTc exists, was then supported by the demonstration that IL-6 can per se reproduce such ECG abnormality in an animal model, along with consistent electrophysiological changes in a cell.