Effects of procainamide on a canine model of electropharmacology as assessed by programmed electrical stimulation / 中国药理学通报

ABSTRACT

A canine model of electro-physiologic-electropharmacologic testing on ischemic ventricular tachyarrhythmias were established in the open-chest dogs subjected to programmed electrical stimulation (PES) on 5~8days after acute my-ocardial infarction produced with two -stage occlusion of left anteriol decending coronary artery (LAD) followed by partly reperfusion. The electrophysiologic -electropharmacologic effects of pro-cainamide (PA ) were observed in this canine model. pA distinctly lengthened the QTc interval and the effective refractory period ( ERP) of normal and infarct myocardium in both ventricles and decreasedthe dispersion of ERP in infarct myocardium (IDR) as well as the dispersion of ERP in left ventricle (VDR). The PES - induced ventricular tachycardia (VT) or ventricular fibrillation (VF) was prevented in 5 out of 6 PA treated dogs (n = 6),Normal saline (NS) did not prevented PES- induced VT/VF. The results suggest that PA may be effective in preventing the onset of reentrant ventricular tachyarrhythmias after myocardium ischemic damage.