Class III effects of dofetilide and arrhythmias are modulated by [K+]o in an in vitro model of simulated-ischemia and reperfusion in guinea-pig ventricular myocardium

Different arrhythmogenic mechanisms are involved in this model at different [K+]o with 8 mmol/l providing relative protection. Class III effects of dofetilide are evident in the normal zone when in the ischemic-like zone [K+]o ranges from 4 to 12 mmol/l. Thus dofetilide did not increase dispersion of repolarization and had either an antiarrhythmic or a neutral effect during ischemia/reperfusion.