“5 In the presence of … drug concentrations, however, pinacidil decreased the QRS prolongation … by mexiletine (−17%) and quinidine (− 8%), but not that induced by flecainide: this effect was already maximal at the lower concentration … (10 μm) and there was no relationship between pinacidil‐induced JT shortening and QRS changes.”
“6 Flecainide, but not quinidine and mexiletine, antagonized the JT shortening induced by pinacidil ; furthermore, no drug modified the JTp/JT decrease induced by pinacidil.”