多巴酚丁胺对冬眠心肌灌注、代谢及功能的影响及其临床意义  

Effects of dobutamine on perfusion, metabolism and contraction of hibernating myocardium

作　　者：陈良龙[1] 罗育坤[1] 邱罕凡[1] 孙旭东[1] 洪华山[1] 

机构地区：[1]福建医科大学附属协和医院心内科,福州350001

出　　处：《中华心血管病杂志》2000年第5期379-382,共4页Chinese Journal of Cardiology

基　　金：福建省自然科学基金资助!(c970 0 41)

摘　　要：目的　探讨多巴酚丁胺负荷试验 (DST)对冬眠心肌灌注、代谢和功能的影响及其临床意义。方法　结扎猪冠状动脉左前降支制作心肌冬眠模型。 2 0只猪在冠状动脉结扎前的非缺血阶段作为对照组 ,然后按缺血程度分成中度和重度缺血的心肌冬眠分别为甲组和乙组 ,每组各 10只。采用DST“唤醒”冬眠心肌 ,测量各试验阶段心肌灌注 (MBF)、代谢 (MVO2 、Qlac、pHv)、收缩功能 (WT)及血流动力学 (RPP)指标 ,比较组内及组间各阶段上述指标变化。结果　在DST过程中 :MBF甲组逐渐增加 ,但在最大剂量时下降 ,而乙组无明显增加 ;MVO2 甲组逐渐增加 ,而乙组无明显增加 ;心肌代谢紊乱及酸中毒甲组在DST较高剂量才发生 ,而乙组立即发生 ;WT在甲组先增强后减弱 ,呈“双相反应” ,而乙组先不变后进行性减弱 ,呈“单相反应”。DST使对照组MBF和WT进行性增加 ,无代谢紊乱。DST使三组RPP逐步显著增加。结论　DST使冬眠心肌灌注和收缩功能平衡失调而再出现代谢紊乱。若冠状动脉狭窄较轻 ,DST使冬眠心肌收缩功能呈“双相反应” ,可由超声心动图检出 ,并可与顿抑和梗死心肌鉴别 ;若冠状动脉狭窄较重 ,DST使冬眠心肌收缩功能呈“单相反应” ,超声心动图难与梗死心肌鉴别。Objective To evaluate the effects of dobutamine on the perfusion, metabolism and contraction of hibernating myocardium and its clinical significance. Methods A myocardiac hibernating model was created by ligating LAD in 20 pigs. The animals were divided into group A (with moderate myocardiac ischemia) and B (with severe myocardiac ischemia), each consisted of 10 animals; the animals before ligating LAD served as controls (CL). A standard dobutamine stress test (DST) was performed for waking up the hibernating myocardium, and regional myocardiac perfusion (MBF), metabolism (MVO 2, Q 1ac , pH v), contraction (WT) and hemodynamics (RPP) were measured and compared at each experimental stage in and between groups. Results During DST,MBF increased gradually in group A with a decrease at peak dose, and did not significantly alter in group B; MVO 2, increased gradually in group A, with an insignificant increase in group B; myocardiac metabolic disorder and acidosis were induced gradually in group A and immediately in group B; WT augmented at lower dose and reduced at peak dose in group A, resulting in a bi phasic response, and unaltered at low dose and then progressively decreased in group B, presenting an uni phasic response. MBF and WT increased progressively without regional metabolic disorder in CL. RPP progressively increased in each group. The parameters between groups at each corresponding stage were significantly different. Conclusion DST impairs the balance between perfusion, metabolism and contraction of hibernating myocardium, leading to severe myocardial metabolic disorder. When coronary stenosis is mild, DST induces a bi phasic contracting response in hibernating myocardium and echocardiagraphy is able to differentiate hibernating myocardium from stunned or infarcted myocardium. When the stenosis is severe, only an uni phasic contracting response happens during DST and echocardiagraphy is unable to differentiate hibernating myocardium from infarcted myocardium.

关 键 词：冬眠心肌 灌注 代谢 心功能 多巴酚丁胺 

分 类 号：R542[医药卫生—心血管疾病]