Mechanical energetics in patients with left ventricular hypertrophy and/or dysfunction

左心室肥厚和/或功能障碍患者的机械能量学

基本信息

批准号：
06670706
负责人：
YOKOTA Mitsuhiro
金额：
$ 1.34万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

项目摘要

Idiopathic dilated cardiomyopathy is a fetal heart disease that severely compromises cardiac performance. One problem is that this disease is extremely resistant to therapy and no inotropic agent has been reported to decrease its mortality. Various aspects of this disease including the pathophysiology, hemodynemics have been analyzed and reported, but this study have focused on how these variable affect myocardial energetics. By means of left ventricular pressure-volume relations, we investigated left ventricular contractility, arterial loading conditions and the way their interaction affects myocardial energetics in patients with idiopathic dilated cardiomyopathy. The effects fo 3 inotropic agents including dobutamine, MS-857 and OPC-18790 with different mechanism of action were investigated. A phosphodiesterase inhibitor MS-857 and OPC-18790 works mainly by inhibiting phosphodiesterase, and OPC-18790 prolongs the action potential of myocyte.Methods. Pressure-volume data were measured in 33 patients with idiopathic dilated cardiomyopathy by using a conductance catheter, and myocardial oxygen consumption was obtained simultaneously by a double-themistor coronary sinus catheter (Wilton-Webster Laboratories). Fogarty catheter was placed in the inferior vena cava and was inflated transiently for the determination of left ventricular pressure-volume relation.Conclusions. The degree of ventriculoarterial coupling is far from optimal and the cardiovascular performance is severely depressed mechanically and energetically in patients with indiopathic dilated cardiomyopathy. Althought inotropic agents improve the coupling and increased the work efficiency, but not enough to optimize the coupling condition. It appears that myocardial oxygen utilization is regulated to maintain a constant mechanical efficiency.

特发性扩张型心肌病是一种严重损害心脏功能的胎儿心脏病。一个问题是这种疾病对治疗具有极强的抵抗力，并且没有报道称正性肌力药物可以降低其死亡率。该疾病的各个方面，包括病理生理学、血流动力学都已被分析和报道，但本研究的重点是这些变量如何影响心肌能量。通过左心室压力-容积关系，我们研究了特发性扩张型心肌病患者的左心室收缩力、动脉负荷状况及其相互作用影响心肌能量的方式。研究了多巴酚丁胺、MS-857和OPC-18790等3种不同作用机制正性肌力药物的作用。磷酸二酯酶抑制剂MS-857和OPC-18790主要通过抑制磷酸二酯酶起作用，OPC-18790延长肌细胞的动作电位。方法。使用电导导管测量 33 例特发性扩张型心肌病患者的压力-容积数据，并通过双热敏电阻冠状窦导管（Wilton-Webster Laboratories）同时获得心肌耗氧量。 Fogarty导管置入下腔静脉并短暂充气，测定左心室压力-容积关系。结论。特发性扩张型心肌病患者的心室动脉耦合程度远非最佳，心血管功能在机械和能量方面严重下降。虽然正性肌力剂改善了耦合并提高了工作效率，但不足以优化耦合条件。看来心肌氧利用受到调节以维持恒定的机械效率。