Lake-Bakaar Gerond, Ahmed Muneeb, Evenson Amy, Bonder Alan, Faintuch Salomao, Sundaram Vinay
Gerond Lake-Bakaar, Muneeb Ahmed, Amy Evenson, Alan Bonder, Salomao Faintuch, Vinay Sundaram, Liver Tumor Center, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States.
World J Hepatol. 2015 Jan 27;7(1):28-32. doi: 10.4254/wjh.v7.i1.28.
The onset of hepatic decompensation in cirrhosis heralds an accelerated downhill course with poor outcome. The sole predictor of this decompensation in cirrhosis is increased hepatic vein to portal vein gradient hepatic venous pressure gradient (HVPG). Surrogate markers of liver function or hepatic reserve appear to be less relevant. The hepatic sinusoids become less elastic and more rigid as liver fibrosis and cirrhosis progress. We propose that the Hagen-Poiseuille's law, which applies to rigid, but not elastic vessels, determines the pressure-flow characteristics in the sinusoids. In the rigid cirrhotic liver, HVPG rises dramatically with any change in net surface area or radius, r(4) of the vasculature that follows surgical resection. This review relates liver stiffness to the risk of decompensation in patients with cirrhosis. The liver has a unique dual blood supply comprising a low pressure portal vein and high pressure hepatic artery. We compare the complexity of autoregulation in the normal elastic liver with that in the rigid cirrhotic liver. Therapeutic modalities to reduce portal pressure may reduce the risk of hepatic decompensation and improve outcomes in cirrhosis.
肝硬化患者发生肝失代偿预示着病情加速恶化，预后不良。肝硬化患者发生这种失代偿的唯一预测指标是肝静脉与门静脉压力梯度（HVPG）升高。肝功能或肝储备的替代指标似乎相关性较小。随着肝纤维化和肝硬化的进展，肝血窦弹性降低、硬度增加。我们提出，适用于刚性而非弹性血管的哈根-泊肃叶定律决定了血窦中的压力-流量特性。在刚性的肝硬化肝脏中，HVPG会随着手术切除后血管系统净表面积或半径r⁴的任何变化而急剧升高。本综述探讨了肝脏硬度与肝硬化患者失代偿风险之间的关系。肝脏具有独特的双重血液供应，包括低压门静脉和高压肝动脉。我们比较了正常弹性肝脏与刚性肝硬化肝脏中自动调节的复杂性。降低门静脉压力的治疗方式可能会降低肝失代偿的风险并改善肝硬化患者的预后。
