Objectives To observe the electrophysiologic effects of propafenone (Prop) on ischemic ventricular tachyarrhythmias. Methods A canine ischemic ventricular tachyarrhythmia model was established in open-chest dogs sub...Objectives To observe the electrophysiologic effects of propafenone (Prop) on ischemic ventricular tachyarrhythmias. Methods A canine ischemic ventricular tachyarrhythmia model was established in open-chest dogs subjected to programmed electrical stimulation (PES) on 5-8 days after acute myocardial infarction. The electrophysiologic effects of propafenone were observed in the model. Results Propafenone distinctly lengthened the QTc interval (P 〉 0.01) and effective refractory period (ERP) of normal and ischemic ventricular myocardium (NERP and IERP) respectively (P 〉 0.01), decreased the dispersion of ERP in ischemic myocardium and in left ventricle (P 〉 0.01), and increased the diastolic excitability threshold of normal and ischemic ventricular myoeardium remarkably (P 〉 0.01). Propafenone effectively prevented PES-induced ventricular tachycardia (VT) or ventricular fibrillation (VF) (P 〉 0.01) and ischemia-induced VT/VF (P 〉 0.05). Conclusions The results indicated that the canine model produced by our methods is a worthy and reliable one, propafenone may be effective in preventing the onset of VT / VF after myocardial ischemic damage in dogs, and deserve further attention as an antifibrillatory agent.展开更多
Increased QT dispersion in the surface ECG (QTd = QTmax minus QTmin) is considered as an indicator of electrical inhomogeneitv and a useful predictor for severe ventricular arrhythmia and sudden cardiac death in patie...Increased QT dispersion in the surface ECG (QTd = QTmax minus QTmin) is considered as an indicator of electrical inhomogeneitv and a useful predictor for severe ventricular arrhythmia and sudden cardiac death in patients with different heart diseases. Patients with ischemic and idiopathic cardiomyopathy have a very high incidence of severe ventricular arrhythmia and sudden cardiac death. We compared QT, QTc. JT and JTc dispersion in ischemic (ICMP) and idopathic (CCMP) cardiomyopathy patients with and without severe ventricular arrhythmia and normal controls.展开更多
文摘Objectives To observe the electrophysiologic effects of propafenone (Prop) on ischemic ventricular tachyarrhythmias. Methods A canine ischemic ventricular tachyarrhythmia model was established in open-chest dogs subjected to programmed electrical stimulation (PES) on 5-8 days after acute myocardial infarction. The electrophysiologic effects of propafenone were observed in the model. Results Propafenone distinctly lengthened the QTc interval (P 〉 0.01) and effective refractory period (ERP) of normal and ischemic ventricular myocardium (NERP and IERP) respectively (P 〉 0.01), decreased the dispersion of ERP in ischemic myocardium and in left ventricle (P 〉 0.01), and increased the diastolic excitability threshold of normal and ischemic ventricular myoeardium remarkably (P 〉 0.01). Propafenone effectively prevented PES-induced ventricular tachycardia (VT) or ventricular fibrillation (VF) (P 〉 0.01) and ischemia-induced VT/VF (P 〉 0.05). Conclusions The results indicated that the canine model produced by our methods is a worthy and reliable one, propafenone may be effective in preventing the onset of VT / VF after myocardial ischemic damage in dogs, and deserve further attention as an antifibrillatory agent.
文摘Increased QT dispersion in the surface ECG (QTd = QTmax minus QTmin) is considered as an indicator of electrical inhomogeneitv and a useful predictor for severe ventricular arrhythmia and sudden cardiac death in patients with different heart diseases. Patients with ischemic and idiopathic cardiomyopathy have a very high incidence of severe ventricular arrhythmia and sudden cardiac death. We compared QT, QTc. JT and JTc dispersion in ischemic (ICMP) and idopathic (CCMP) cardiomyopathy patients with and without severe ventricular arrhythmia and normal controls.