HEMODYNAMIC EFFECTS OF DOBUTAMINE & MILRINONE

这是一项随机、双盲、平行分组的积极对照试验，为期18个月，共有72名患者。这项研究将在两个地点进行，犹他大学GCRC和科罗拉多大学GCRC。因特发性扩张型心肌病而导致NYHA II-IV级心力衰竭的患者将接受布汀多洛或美托洛尔治疗，以确定与这两种药物相关的心肌基因表达的变化。与心肌功能和重塑改变相关的基因表达变化也在研究中。如果布汀多洛或美托洛尔被证明能降低心脏肾上腺素能驱动力，那么这种效应与心肌基因表达变化的关系将被确定。如果布汀多洛或美托洛尔降低肾素-血管紧张素系统的活性，那么这种效应的关系也将与心肌基因表达的变化相关。米力农是一种磷酸二酯酶抑制剂，该药物的使用将使研究人员能够确定该药物是否增强了布吲哚的作用，这表明布吲哚也可能通过环磷酸腺苷依赖的机制发挥作用。这项研究还处于早期阶段，但还没有足够成熟的数据来报告。

This is a randomized, double-blind, parallel group, active-controlled trial of eighteen months' duration and a total of 72 patients. The study will be performed at two sites, the University of Utah GCRC and the University of Colorado GCRC. Patients with NYHA class II-IV heart failure due to idiopathic dilated cardiomyopathy will be treated with either bucindolol or metoprolol to determine changes in myocardial gene expression associated with either of these drugs. Changes in gene expression associated with alterations in myocardial function and remodeling are also under study. If bucindolol or metoprolol proves to lower cardiac adrenergic drive, then the relationship of this effect to changes in myocardial gene expression will be defined. If bucindolol or metoprolol lowers activity of the renin-angiotensin system, then the relationship of this effect will also be correlated with changes in myocardial gene expression. Milrinone is a phosphodiesterase inhibitor and the use of this agent will enable the investigators to determine if the effects of bucindolol are enhanced by this drug, suggesting that bucindolol may also act through a cyclic-AMP-dependent mechanism. This study is in its earliest phases but no data are mature enough to report.