Objective:To observe spontaneous functional improvement of dyssynergic segments improvement in patients with acute myocardial infarction(AMI)and evaluate the predicting value of low dose dobutamine(Dob) nitrate echocardiography for the improvement.

• 目的 :观察急性心肌梗塞 (AMI)运动异常节段功能的自发性改善 ,评价小剂量多巴酚丁胺 (Dob) -硝酸酯二维超声心动图 (2 DE)试验的预测价值和安全性。