A pair of epicardial electrodes was sutured on the border zone of the ischemic area of the left ventricle for continuous recording of the ventricular surface electrograms. QT interval was assessed from the lead II ECG and the ventricular surface electrogram. The QTc interval was calculated using Bazett’s formula,

Effects of class III antiarrhythmic drugs on ventricular arrhythmias in dogs
where RR is the RR interval.
Heart rate was measured from the lead II ECG and blood pressure was continuously monitored through a double lumen arterial cannula in the femoral artery.
Production of PES-induced arrhythmia in dogs with ‘old’ myocardial infarction: As reported previously , beagle dogs, six to eight for each drug experiment, of either sex were anesthetized initially with intravenous thiopental sodium 30 mg/kg and intubated. The chest was opened and a two-stage coronary ligation of the left anterior descending artery was performed under halothane anesthesia, then the chest was closed. Seven to 12 days after surgery, when myocardial infarction was established, the dogs were anesthetized with intravenous pentobarbital sodium 30 mg/kg plus 5 mg/kg/h and intubated. The chest was opened again and the PES was performed through silver bipolar epicardial electrodes, which were sutured on the noninfarcted left ventricular wall. The electrodes were connected to a programmable stimulator (Nihon Kohden SS-201J) through an isolator (Nihon Kohden SEN-7203). Lead II ECG, and instantaneous and mean blood pressures from a cannula in the femoral artery were continuously recorded. Efficient treatment has got less costly: find viagra super active online buy here at best online pharmacy.