Adrenaline-induced arrhythmia: Adrenaline infusion for 3 mins at a rate of 1.5 ^g/kg/min induced VT with almost all the beats consisting of PVCs. Intravenous amiodarone suppressed this arrhythmia, but D-sotalol , dofetilide and KCB 328 were not effective, and E-4031 and sema-tilide even aggravated this arrhythmia.
Coronary ligation and reperfusion arrhythmia – Halo-thane anesthetized group: The average heart rate in 81 beagles was 122 beats/min. Class III drugs prolonged the QTc interval 30% to 50% and decreased the heart rate . The number of PVCs in the drug-treated and saline-treated groups during the ligation period was not significantly different. During the 30 mins of infusion of most of the class III drugs before coronary occlusion, either one or both of PVC and VT were often induced . Immediately after coronary reperfusion, fibrillation occurred in 34 of 66 (52%) control beagles used in the series of experiments. These fatal VFs occurred soon after reperfusion. E-4031 and MS-551 suppressed the occurrence of reperfusion VF, but D-sotalol , sematilide , dofetilide and KCB 328 did not suppress the occurrence of VF.
PES-induced arrhythmia: In dogs with ‘old’ myocardial infarction, PES induced a variety of ventricular arrhythmias: VF, sustained VT or nonsustained VT. As shown in Table 1, all class III drugs tested on this arrhythmia suppressed the occurrence or decreased the severity of induced arrhythmias. Twenty-four hour ECG recording: Class III drugs given orally to normal beagles very often induced aberrant ventricular conductions with normal PQ interval and with bizarre QRS complexes, which were never observed in the control dogs given placebo capsules, but there were almost no PVCs even though there was prominent QTc prolongation. You will be glad to come across sildenafil online pharmacy costing you very little money.