Santamore W P, Constantinescu M, Shaffer T
Section of Cardiology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27103.
Ann Biomed Eng. 1988;16(2):215-34. doi: 10.1007/BF02364582.
Based on the balance of forces across the interventricular septum, we developed a theoretical analysis to explain how one ventricle can directly influence the filling characteristics of the other ventricle. The analysis indicated that the pressure and volume transfer were related to the relative compliances of the interventricular septum and ventricular free walls. The present study examined whether the theoretical analysis could be used to predict changes in ventricular interdependence caused by altering regional compliance. To examine this hypothesis, hearts were removed from 18 dogs and placed in cool cardioplegic solution. Balloons were inserted into each ventricle, and the left and right pressure (delta P1, delta Pr) and volume (delta V1, delta Vr) changes caused by changing the pressure and volume of the other ventricle were recorded. After the initial measurements, acute changes in left ventricular free wall compliance (n = 6), septal compliance (n = 6), and right ventricular free wall compliance (n = 6) were induced by glutaraldehyde injections. As predicted by the theoretical analysis, decreasing left ventricular free wall compliance increased delta P1/delta Pr, delta P1/delta Vr, delta Pr/delta V1, and delta Vr/delta V1 significantly (P less than 0.05) by 89 +/- 15, 155 +/- 33, 282 +/- 65, and 112 +/- 22% (mean +/- SEM), respectively. Decreasing septal compliance decreases delta P1/delta Pr, delta V1/delta Pr, delta V1/delta Vr, delta Pr/delta P1, delta Vr/delta P1, and delta Vr/delta V1 significantly (P less than 0.05) by 48 +/- 7, 71 +/- 10, 69 +/- 14, 48 +/- 7, 62 +/- 8, and 57 +/- 13%, respectively. Decreasing right ventricular free wall compliance increased delta P1/delta Vr, delta V1/delta Vr, delta Pr/delta P1, and delta Pr/delta V1 significantly (P less than 0.05) by 97 +/- 25, 79 +/- 20, 57 +/- 18, and 59 +/- 23%, respectively. Furthermore, these alterations in ventricular coupling were predictable: The actual and predicted percentage changes in the transfer functions were in close agreement. The results of these studies show predictable alterations in the mechanical coupling between the ventricles following changes in right ventricular, septal, and left ventricular free wall compliances.
基于跨室间隔的力平衡，我们进行了一项理论分析，以解释一个心室如何直接影响另一个心室的充盈特性。分析表明，压力和容积传递与室间隔和心室游离壁的相对顺应性有关。本研究检验了该理论分析是否可用于预测因改变局部顺应性而导致的心室相互依存性变化。为检验这一假设，从18只犬身上取出心脏并置于冷心脏停搏液中。将球囊插入每个心室，记录因改变另一个心室的压力和容积而引起的左、右压力（ΔP1、ΔPr）和容积（ΔV1、ΔVr）变化。在初始测量后，通过注射戊二醛诱导左心室游离壁顺应性（n = 6）、室间隔顺应性（n = 6）和右心室游离壁顺应性（n = 6）的急性变化。如理论分析所预测，降低左心室游离壁顺应性会使ΔP1/ΔPr、ΔP1/ΔVr、ΔPr/ΔV1和ΔVr/ΔV1分别显著增加（P < 0.05）89±15%、155±33%、282±65%和112±22%（平均值±标准误）。降低室间隔顺应性会使ΔP1/ΔPr、ΔV1/ΔPr、ΔV1/ΔVr、ΔPr/ΔP1、ΔVr/ΔP1和ΔVr/ΔV1分别显著降低（P < 0.05）48±7%、71±10%、69±14%、48±7%、62±8%和57±13%。降低右心室游离壁顺应性会使ΔP1/ΔVr、ΔV1/ΔVr、ΔPr/ΔP1和ΔPr/ΔV1分别显著增加（P < 0.05）97±25%、79±20%、57±18%和59±23%。此外，心室耦合的这些改变是可预测的：传递函数的实际和预测百分比变化密切一致。这些研究结果表明，右心室、室间隔和左心室游离壁顺应性改变后，心室之间的机械耦合会发生可预测的改变。
