A mechanism for shifts in the diastolic, left ventricular, pressure-volume curve: the role of the pericardium.
A mechanism for shifts in the diastolic, left ventricular, pressure-volume curve: the role of the pericardium.
复制标题
舒张压、左心室、压力-容量曲线变化的机制：心包的作用。
DOI：
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发表时间：
1978
期刊：
影响因子：
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通讯作者：
W. Parmley
中科院分区：
文献类型：
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作者：
J. Tyberg;G. Misbach;S. Glantz;W. Moores;W. Parmley
试图通过心肌僵硬度的变化来解释压力-容积关系的急性变化的尝试没有得到动物实验的支持，并且计算表明，使一半心室僵硬很难解释临床观察到的曲线向上移动。在心包打开和关闭的情况下，对开胸麻醉犬进行容量负荷时收集的数据表明，当心包关闭时，右心室压力比左心室尺寸更能预测左室舒张压。这些数据支持这样一种假设，即压力-容积曲线的急剧上升可能是由心包压升高引起的，而心包内内容物的容积升高又引起了心包压升高。这是因为左室舒张压的测量值等于心包和心肌之间的压差之和。因此，心包压升高使测量的心室舒张压升高，而心室容积没有变化：因此，压力-容积曲线向上移动。
Attempts to explain acute shifts in the pressure-volume relationship by changes in myocardial stiffness have been unsupported by animal experimentation and discouraged by calculations showing that making half the ventricle rigid would hardly account for the clinically observed upward shifts in the curve. Data collected in open-chest anesthetized dogs during volume loading with the pericardium open and closed indicate that when the pericardium is closed, left ventricular enddiastolic pressure is better predicted by right ventricular pressure than by left ventricular dimensions. These data support the hypothesis that acute, upward shift in the pressure-volume curve may be caused by an increase in pericardial pressure, in turn caused by an increase in the volume of the intrapericardial contents. This follows from the fact that measured left ventricular diastolic pressure is equal to the sum of the pressure differences accross the myocardium and the pericardium. Thus, increases in pericardial pressure raise measured ventricular diastolic pressure without change in ventricular volume: hence, an upward shift in the pressure-volume curve.