MYOCARDIAL INOTROPIC RESERVE IN ASYMTOMATIC AORTIC REGURGITATION

无症状主动脉瓣反流的心肌肌力储备

• 批准号: 3779634
• 负责人: J A PANZA
• 金额: --
• 依托单位: NATIONAL HEART, LUNG, AND BLOOD INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3779634
• 关键词: aortic valve disorder; dobutamine; heart contraction; heart dimension /size; heart disorder diagnosis; human subject; intracardiac volume

Previous studies have shown that resting left ventricular dimensions and basal ejection fraction are useful indices of cardiac function for the assessment and follow-up of patients with aortic regurgitation. However, the relation to the inotropic reserve of the myocardium has not been investigated previously. To address this issue, we studied the response of increasing doses of dobutamine (2.5 to 20 microg/kg/min) during transesophageal examination in 14 patients with aortic regurgitation who were asymptomatic and had normal resting ejection fraction. In each of these patients, there was dilatation of the left ventricle as a consequence of the valvular disorder. The myocardial inotropic reserve was measured as systolic thickening at each dose of dobutamine. In the overall group of patients studied, no correlation was observed between the myocardial response to dobutamine and resting left ventricular dimensions or ejection fraction. Thus, the results of this study indicate that the myocardial inotropic reserve in patients with aortic regurgitation is not related to either the degree of dilatation or the systolic function at rest of the left ventricle. It remains to be determined whether this index of myocardial contractile state is a predictor of further left ventricular dilatation, dysfunction, or development of symptoms during follow-up that may indicate need for aortic valve replacement.

以前的研究表明，静息时左心室尺寸和 基础射血分数是心脏功能的有用指标， 主动脉瓣返流患者的评估和随访。 然而，在这方面， 与心肌的正性肌力储备的关系尚未被 以前调查过。 为了解决这个问题，我们研究了 增加多巴酚丁胺剂量（2.5至20微克/公斤/分钟）， 对14例主动脉瓣关闭不全患者进行了经食管检查， 无症状，静息射血分数正常。 的每一个中 这些患者的左心室扩张， 瓣膜疾病的后果。 心肌正性肌力储备 以多巴酚丁胺各剂量下的收缩期增厚来衡量。 在 在研究的整个患者组中，未观察到 多巴酚丁胺心肌反应与静息左室 尺寸或射血分数。 因此，本研究的结果 表明主动脉瓣狭窄患者的心肌正性肌力储备 反流与扩张程度或 左心室静息时的收缩功能。 还有待 确定这一心肌收缩状态指数是否是 进一步左心室扩张、功能障碍的预测因子，或 随访期间出现可能表明需要 主动脉瓣置换术