Abstract: Objective To investigate the functional changes in the myocardium afler successful resuscitation from ventricular fibrillation(VF). Methods Ventricular fibrillation was induced in Taihu-pigs with an alternating current(AC) delivered to the right ventricular endocardium. Afler either 2 or 6 minutes of untreated ventricular fibrillation,the animals were attempted to defibrillate. Then transthoracic echocardiography was applied to evaluate myocardial function after successful resuscitation. Results Myocardial dysfunction of all animals after successful resuscitation were observed,which had remarkable improvement when they survived more than 72 hours. Myocardial function of the animals afler 6 min of untreated ventricular fibrillation had more serious impairment than that after 2 minutes(P＜0.05). Conclusion As the duration of untreated ventricular fibrillation was prolonged,the severity of postresuscitation myocardial dysfunction would be increased. The myocardial dysfunction with left ventricle dilation may be reversible probably.

Key words: Taihu-Pig, Ventricular fibrillation, Defibrillation, Echocardiography