Beppu S, Matsuhisa M, Izumi S, Masuda Y, Nagata S, Park Y D, Sakakibara H, Nimura Y
J Cardiogr. 1986 Mar;16(1):193-205.
To elucidate the physioanatomic roles of the pericardium, the alterations in gross anatomy and cardiac motion induced by posture were examined by two-dimensional echocardiography in seven patients with total absence of the left pericardium. Ten healthy subjects were served as controls. The heart was located deeper within the chest at end-diastole in patients with pericardial defect than in healthy subjects, especially in the left lateral decubitus position. With progression of systole, the cardiac apex swung anteriorly with the cardiac base as the fulcrum, and the heart approximated the normal position at end-systole. The deeper the position of the center of the cross-section of the left ventricular cavity at end-diastole, the more exaggerated the swinging motion in systole. The deep location of the heart in end-diastole is considered to result from release from pericardial support, and the systolic tonus of the cardiac muscle restores the apex to nearly normal position. The characteristic swinging motion of the heart and its alterations dependent of posture seemed the signs suggestive of total absence of the pericardium. The shape of the short-axis view of the left ventricular cavity was nearly circular throughout the cardiac cycle. Therefore, paradoxical motion of the ventricular septum observed on M-mode echocardiography in pericardial defect results from the anterior shift of the entire heart overcoming the proper motion of the interventricular septum. The left ventricular dimension become enlarged according to the postural change from the right to left lateral decubitus positions regardless of the presence or absence of the pericardium. The right ventricular cavity became enlarged in the left lateral decubitus position in patients with pericardial defect. The elevation of hydrostatic pressure due to postural change was considered excessive due to the absence of the pericardium. In the left lateral decubitus position, systolic excursions of the mitral and tricuspid rings became more prominent in healthy subjects, whereas these excursions, particularly of the tricuspid ring, were reduced in patients with pericardial defect. Depressed tricuspid ring motion was also observed in the right lateral position in cases with pericardial defects. The reduced excursion of the tricuspid, ring and the right ventricular dilatation may affect systemic venous return to the right atrium.
为阐明心包的生理解剖学作用，我们通过二维超声心动图检查了7例完全缺失左心包患者因体位改变引起的大体解剖结构和心脏运动变化。选取10名健康受试者作为对照。与健康受试者相比，心包缺损患者在舒张末期心脏位于胸腔内更深的位置，尤其是在左侧卧位时。随着收缩期的进展，心尖以心底为支点向前摆动，在收缩末期心脏接近正常位置。舒张末期左心室腔横截面中心位置越深，收缩期摆动运动越明显。舒张末期心脏位置较深被认为是由于心包支持作用解除所致，而心肌的收缩张力使心尖恢复到接近正常位置。心脏的特征性摆动运动及其随体位的变化似乎提示心包完全缺失。在整个心动周期中，左心室腔短轴视图的形状几乎呈圆形。因此，心包缺损患者M型超声心动图上观察到的室间隔矛盾运动是由于整个心脏向前移位克服了室间隔的正常运动所致。无论有无心包，从右侧卧位到左侧卧位的体位变化都会使左心室尺寸增大。心包缺损患者在左侧卧位时右心室腔增大。由于心包缺失，体位改变引起的静水压力升高被认为过高。在左侧卧位时，健康受试者二尖瓣和三尖瓣环的收缩期移动更为明显，而心包缺损患者这些移动，尤其是三尖瓣环的移动则减少。在心包缺损病例的右侧卧位也观察到三尖瓣环运动减弱。三尖瓣环移动减弱和右心室扩张可能会影响体循环静脉血回流至右心房。
