Vallet B, Dupuis B, Chopin C
Service de Réanimation Polyvalente, Lille.
Ann Cardiol Angeiol (Paris). 1991 Jun;40(6):397-402.
High levels of circulating catecholamines associated with heart failure down-regulate cardiac beta-receptors, with a more pronounced effect on beta-1 receptors, leading to impaired inotropic effect. The use of exogenous inotropic agents is therefore a logical therapeutic approach in heart failure. Dobutamine is a synthetic catecholamine that acts on alpha-1, beta-1 and beta-2 adrenergic receptors. In the heart, the stimulation of these receptors produces a relatively strong, additive inotropic effect and a relatively weak chronotropic effect. In the vasculature, alpha-1 agonist activity (vasoconstriction) balances the beta-2 agonist effect (vasodilatation). In clinical use, dobutamine has a rapid onset of action and a short half-life. It increases myocardial contractility, while the reflex reduction in sympathetic tone, in response to augmentation of stroke volume, leads to a decrease in total peripheral resistance. The expected hemodynamic effects are an increase in cardiac output and a decrease in systemic vascular resistance without significant change in arterial pressure or heart rate. In acute cardiac failure state with elevated afterload pressures, resulting from myocardial dysfunction, dobutamine therapy remains, nowadays, the reference.
与心力衰竭相关的循环儿茶酚胺水平升高会下调心脏β受体，对β-1受体的影响更为显著，导致心肌收缩力受损。因此，使用外源性正性肌力药物是治疗心力衰竭的合理方法。多巴酚丁胺是一种合成儿茶酚胺，作用于α-1、β-1和β-2肾上腺素能受体。在心脏中，刺激这些受体可产生相对较强的累加性正性肌力作用和相对较弱的变时作用。在血管系统中，α-1激动剂活性（血管收缩）可平衡β-2激动剂效应（血管舒张）。在临床应用中，多巴酚丁胺起效迅速且半衰期短。它可增加心肌收缩力，而由于每搏量增加导致的交感神经张力反射性降低会使总外周阻力下降。预期的血流动力学效应是心输出量增加和全身血管阻力降低，而动脉压或心率无显著变化。在因心肌功能障碍导致后负荷压力升高的急性心力衰竭状态下，多巴酚丁胺治疗至今仍是标准治疗方法。
