Mechanical Interactions between Four Heart Chambers with and without the Pericardium in Canine Hearts
Mechanical Interactions between Four Heart Chambers with and without the Pericardium in Canine Hearts
复制标题
犬心脏有心包和无心包的四个心室之间的机械相互作用
作者：
Y. Maruyama;K. Ashikawa;S. Isoyama;E. Ino;T. Takishima
我们从15只杂种狗的死后切除的心包完整的心脏，从心室压力-容积关系的角度研究了四个心室之间的力学相互作用。所研究的相互作用是(1)心房与心室之间的相互作用，(2)右心室与左心室之间的相互作用，(3)心房与一个心室与另一个心室之间的相互作用，以及(4)左右心房与右心室与左心室之间的相互作用。为此，我们在不损伤心包的情况下将柔软的球囊插入四个心腔，即切开没有被心包覆盖的心房底部。我们通过改变与每个球囊相连的储层的高度，获得了其他三个心室在恒定压力下的右心室和/或左心室压力-容积关系。因此，去除心包后，心房压力在5 ~ 30 cm H2O范围内升高，两种心室压力-容积关系几乎不受影响，尽管心室因对侧心室压力增加相同幅度而变得不那么顺从。另一方面，在心包完好的情况下，房压升高的影响是明显的。此外，所有机械相互作用在心包完整的情况下都显著增强。因此，心包在这些机械相互作用中起着重要的作用，特别是当所有心室的充盈压力同时增加时。在临床上，这些发现可能对理解与各种心脏疾病有关的心室功能很重要，尤其是急性心力衰竭。
By using excised postmortem hearts obtained from 15 mongrel dogs with the pericardium intact, we investigated mechanical interactions between the four heart chambers from the standpoint of ventricular pressure-volume relationships. The interactions investigated were those between (1) the atrium and the ventricle, (2) the right ventricle and left ventricles, (3) the atrium and one ventricle vs. the other ventricle, and finally (4) the left and right atrium and the right ventricle vs. the left ventricle. For these purposes, we inserted compliant balloons into the four heart chambers without injuring the pericardium, i.e., we incised the base of the atria which was not covered with the pericardium. We obtained the right and/or left ventricular pressure-volume relationships under a constant pressure in three other heart chambers by changing the height of the reservoir connected to each balloon. As a result, both ventricular pressure-volume relationships were hardly affected by an increase in the atrial pressure ranging from 5 to 30 cm H2O with the pericardium removed, although the ventricle became less compliant due to an increase of the same magnitude of the opposite ventricular pressure. On the other hand, the effect of an increase in atrial pressure was distinct with the pericardium intact. Also, all mechanical interactions were enhanced dramatically with the intact pericardium. Thus, the pericardium plays an important role in these mechanical interactions, especially when the filling pressures of all heart chambers increase simultaneously. Clinically, these findings may be important to understanding ventricular functions as related to various heart disease--especially acute heart failure.