Kikuchi F, Mikuniya A, Higashiyama A, Komatsu T, Tamura H, Onodera K, Matsui T, Oike Y
Second Department of Internal Medicine, Hirosaki University School of Medicine.
J Cardiol. 1990;20(2):437-46.
To evaluate left ventricular mechanical energy efficiency and ventriculo-arterial coupling in humans, left ventricular pressure-volume relations were determined using the conductance catheter technique in 20 patients undergoing cardiac catheterization. The results were as follows: 1. A convex, curvilinear relationship was observed between end-systolic pressure-volume relations (Emax) and left ventricular ejection fraction (EF), as shown in the equation of EF = 28.5 x log (Emax) + 39.6 (r = 0.67, p less than 0.01, n = 20); EF remained nearly constant in the range of Emax greater than or equal to 4 mmHg/ml/m2, whereas, EF decreased markedly under the Emax of 4 mmHg/ml/m2. 2. A convex, curvilinear relationship was observed between Emax and mechanical energy efficiency (EW/PVA), as shown in the equation of EW/PVA = 30.5 x log (Emax) + 54.8 (r = 0.83, p less than 0.01, n = 16). 3. A concave, curvilinear relationship was observed between Emax and ventriculo-arterial coupling (Ea/Emax), as shown in the equation of Ea/Emax = -0.8 x (Emax)0.5 + 2.6 (r = -0.85, p less than 0.01, n = 16). Accordingly, EW/PVA was markedly decreased with changes in Emax in the range less than 4 mmHg/ml/m2, although it remained slightly increased above 4 mmHg/ml/m2. Ea/Emax was maintained constant (p less than 0.5) in the range of Emax above 4 mmHg/ml/m2 but was abruptly decreased when Emax was reduced below 4 mmHg/ml/m2. These results indicate that depressed left ventricle attempts to work effectively at the risk of mechanical energy efficiency and with suitable matching by aortic property. Application of pressure-volume relationships provides a new framework for evaluation and treatment of the failing heart.
为评估人类左心室机械能效率和心室 - 动脉耦合，采用电导导管技术对20例接受心导管检查的患者测定左心室压力 - 容积关系。结果如下：1. 观察到收缩末期压力 - 容积关系（Emax）与左心室射血分数（EF）之间呈凸形曲线关系，如方程EF = 28.5 x log（Emax）+ 39.6所示（r = 0.67，p < 0.01，n = 20）；当Emax大于或等于4 mmHg/ml/m2时，EF基本保持恒定，而当Emax低于4 mmHg/ml/m2时，EF显著下降。2. 观察到Emax与机械能效率（EW/PVA）之间呈凸形曲线关系，如方程EW/PVA = 30.5 x log（Emax）+ 54.8所示（r = 0.83，p < 0.01，n = 16）。3. 观察到Emax与心室 - 动脉耦合（Ea/Emax）之间呈凹形曲线关系，如方程Ea/Emax = -0.8 x（Emax）0.5 + 2.6所示（r = -0.85，p < 0.01，n = 16）。因此，当Emax在低于4 mmHg/ml/m2范围内变化时，EW/PVA显著降低，而当Emax高于4 mmHg/ml/m2时，EW/PVA仍略有增加。当Emax高于4 mmHg/ml/m2时，Ea/Emax保持恒定（p < 0.5），但当Emax降至低于4 mmHg/ml/m2时，Ea/Emax会突然下降。这些结果表明，功能低下的左心室试图在机械能效率降低的风险下有效工作，并通过主动脉特性进行适当匹配。压力 - 容积关系的应用为心力衰竭的评估和治疗提供了一个新的框架。
