心肌收缩功能减退,不论其原因孰何,常是引起左室泵功能不全的机制.当严重时,泵衰竭的表现伴有心排出量减低和肺静脉压力增高.所以,用药物治疗以改善心肌收缩力和泵功能,是处理心力衰竭的一个合理治疗途径.拟交感神经药物由于其具有增强心肌收缩力的作用,常被用以治疗急性和慢性心力衰竭.然而,很多心脏兴奋性儿茶酚胺类药物,由于其不良的副作用而限制了它们的临床应用.例如,异丙肾上腺素能使心搏 Myocardial contractile dysfunction, no matter what the cause, is often the mechanism that causes left ventricular dysfunction.When severe, the performance of pump failure accompanied by decreased cardiac output and pulmonary venous pressure.Therefore, with drug treatment to improve myocardial contractility And pump function, is a reasonable treatment for heart failure.Py sympathomimetic drugs are often used to treat acute and chronic heart failure because of their ability to enhance myocardial contractility.However, many cardiac excitatory catecholamines, as a result of Its adverse side effects limit their clinical application, for example, isoproterenol can make heartbeat