Farzaneh-Far Ramin, McKeown Barry H, Dang Dan, Roberts John, Schiller Nelson B, Foster Elyse
Department of Medicine, University of California, San Francisco, California, USA.
Am J Cardiol. 2008 Jan 15;101(2):259-62. doi: 10.1016/j.amjcard.2007.07.086.
The hyperdynamic circulation associated with cirrhosis is typically characterized by high cardiac output and low systemic and pulmonary vascular resistance (PVR). Approximately 4% of cirrhotic patients develop portopulmonary hypertension, which is an important predictor of hemodynamic instability after orthotopic liver transplantation. Doppler estimation of pulmonary artery systolic pressure (PASP) is used as a screening test for the presence of portopulmonary hypertension. We tested the accuracy of a noninvasive measurement of PVR (ratio of peak tricuspid regurgitant velocity [TRV] to right ventricular outflow tract velocity time integral [VTI RVOT]) to detect increased PVR in a population before liver transplantation. We compared test characteristics of the TRV/VTI RVOT ratio to echocardiographically derived PASP for detection of invasively measured PVR >1.5 Wood units. There was no significant correlation between Doppler-derived PASP and invasively measured PVR. There was a moderate and significant correlation between TRV/VTI RVOT ratio and invasively measured PVR. Compared with Doppler-derived PASP, the TRV/VTI RVOT ratio was a more accurate test for PVR >1.5 Wood units. Using a cut-off value of TRV/VTI RVOT >0.12, the sensitivity and negative predictive value for PVR >1.5 Wood units were 100%. In conclusion, the TRV/VTI RVOT ratio is a more accurate screening test for the presence of portopulmonary hypertension than PASP in patients undergoing orthotopic liver transplantation. Routine use of this ratio may decrease the need for invasive hemodynamic assessment in this patient population.
与肝硬化相关的高动力循环通常表现为心输出量高以及体循环和肺血管阻力（PVR）低。约4%的肝硬化患者会发生门肺高压，这是原位肝移植后血流动力学不稳定的重要预测指标。肺动脉收缩压（PASP）的多普勒估计用作门肺高压存在与否的筛查试验。我们测试了一种无创测量PVR（三尖瓣反流峰值速度[TRV]与右心室流出道速度时间积分[VTI RVOT]之比）在肝移植前人群中检测PVR升高的准确性。我们比较了TRV/VTI RVOT比值与经超声心动图得出的PASP在检测有创测量的PVR>1.5伍德单位方面的测试特征。经多普勒得出的PASP与有创测量的PVR之间无显著相关性。TRV/VTI RVOT比值与有创测量的PVR之间存在中度且显著的相关性。与经多普勒得出的PASP相比，TRV/VTI RVOT比值对PVR>1.5伍德单位的检测更准确。使用TRV/VTI RVOT>0.12的临界值，PVR>1.5伍德单位的敏感性和阴性预测值均为100%。总之，对于原位肝移植患者，TRV/VTI RVOT比值在检测门肺高压方面比PASP是更准确的筛查试验。在该患者群体中常规使用此比值可能会减少有创血流动力学评估的需求。
