Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, University of Heidelberg, Heidelberg, Germany.
J Hepatol. 2010 Feb;52(2):206-10. doi: 10.1016/j.jhep.2009.11.018. Epub 2009 Dec 4.
BACKGROUND & AIMS: Liver stiffness (LS) as measured by transient elastography [Fibroscan] offers a novel non-invasive approach to assess liver cirrhosis. Since Fibroscan seems to be unreliable in patients with congestive heart failure, it remains to be determined whether hemodynamic changes affect LS irrespective of fibrosis.
METHODS & RESULTS: Using landrace pigs, we studied the direct relationship between the central venous pressure and LS measured by Fibroscan. Clamping of the inferior caval vein increased LS from 3.1 to 27.8kPa while reopening reversed LS within 5min to almost normal values of 5.1kPa. We then studied LS as a function of venous pressure in the isolated pig liver by clamping the upper and lower caval, portal vein and hepatic artery. The stepwise increase of intravenous pressure to 36cm of water column (3.5kPa) linearly and reversibly increased LS to the upper detection limit of 75kPa. We finally measured LS in 10 patients with decompensated congestive heart failure before and after recompensation. Initial LS was elevated in all patients, in 8 of them to a degree that suggested liver cirrhosis (median 40.7kPa). Upon recompensation with a median weight loss of 3.0kg, LS decreased in all 10 patients down to a median LS of 17.8kPa. Inflammation could not account for increased LS since initial liver enzyme counts were only slightly elevated and did not change significantly.
LS is a direct function of central venous pressure which should be considered when assessing the degree of fibrosis.
瞬时弹性成像(Fibroscan)测量的肝硬度(LS)提供了一种新的非侵入性方法来评估肝硬化。由于 Fibroscan 似乎在充血性心力衰竭患者中不可靠,因此仍需要确定血流动力学变化是否会影响 LS,而与纤维化无关。
我们使用长白猪研究了 Fibroscan 测量的中心静脉压与 LS 之间的直接关系。下腔静脉夹闭使 LS 从 3.1kPa 增加到 27.8kPa,而重新开放则在 5 分钟内将 LS 逆转至接近正常的 5.1kPa。然后,我们通过夹闭上腔静脉、下腔静脉、门静脉和肝动脉来研究孤立猪肝中 LS 作为静脉压的函数。静脉内压力逐步增加到 36cm 水柱(3.5kPa),可使 LS 线性且可逆地增加到 75kPa 的上限。最后,我们在 10 例失代偿性充血性心力衰竭患者中测量了 LS,分别在补偿前后进行了测量。所有患者的初始 LS 均升高,其中 8 例升高到提示肝硬化的程度(中位数 40.7kPa)。在中位体重减轻 3.0kg 的补偿后,10 例患者的 LS 均降低,中位数降至 17.8kPa。初始肝酶计数仅略有升高且变化不明显,因此不能说明 LS 升高是由炎症引起的。
LS 是中心静脉压的直接函数,在评估纤维化程度时应考虑这一因素。