Santamore W P, Burkhoff D
Philadelphia Heart Institute, Presbyterian Medical Center, Pennsylvania 19104.
Am J Physiol. 1991 Jan;260(1 Pt 2):H146-57. doi: 10.1152/ajpheart.1991.260.1.H146.
Because of close anatomic association, the pressure and volume in one ventricle can directly influence the pressure and volume in the opposite ventricle. To examine the importance of ventricular interdependence in controlling the circulation, we developed a computer model in which ventricular interdependence could be turned on and off. Left ventricular chamber contractility, as judged by maximal elastance (Emax), was enhanced on the order of 10% as a result of ventricular interaction, whereas right ventricular Emax was affected by as much as 60% under physiological conditions. With increases in systemic vascular resistance, ventricular interaction caused a smaller stroke volume (SV) decrease than with no interaction. For canine data (SV = 21.4 ml), doubling systemic vascular resistance decreased SV by 3.7 without ventricular interdependence, 3.5 with diastolic ventricular interdependence, and 3.3 ml with diastolic and systolic ventricular interdependence. In contrast, with increases in pulmonary vascular resistance, ventricular interaction caused a greater decrease in SV than with no interaction present. Decreasing left ventricular free wall elastance or right ventricular free wall elastance decreased SV. Diastolic ventricular interdependence reduced the SV changes, whereas systolic ventricular interdependence accentuated the SV changes with alterations in right and left ventricular free-wall elastance. The results of the present simulation demonstrate the importance of ventricular interdependence in the observed responses of the right ventricle to volume overload, pressure overload, and ischemia.
由于解剖结构紧密相连，一个心室的压力和容积可直接影响另一个心室的压力和容积。为研究心室相互依存关系在控制循环中的重要性，我们开发了一个计算机模型，在该模型中，心室相互依存关系可开启或关闭。通过最大弹性（Emax）判断，左心室腔收缩力因心室相互作用增强了约10%，而在生理条件下，右心室Emax受影响高达60%。随着体循环血管阻力增加，与无相互作用相比，心室相互作用导致的每搏输出量（SV）减少幅度更小。对于犬类数据（SV = 21.4 ml），体循环血管阻力加倍时，无心室相互依存关系时SV减少3.7 ml，存在舒张期心室相互依存关系时减少3.5 ml，存在舒张期和收缩期心室相互依存关系时减少3.3 ml。相反，随着肺循环血管阻力增加，与无相互作用相比，心室相互作用导致的SV减少幅度更大。降低左心室游离壁弹性或右心室游离壁弹性会使SV降低。舒张期心室相互依存关系减少了SV变化，而收缩期心室相互依存关系则加剧了右心室和左心室游离壁弹性改变时的SV变化。本模拟结果表明，心室相互依存关系对于观察到的右心室对容量超负荷、压力超负荷和缺血的反应具有重要意义。
