McAvoy N C, Semple S, Richards J M J, Robson A J, Patel D, Jardine A G M, Leyland K, Cooper A S, Newby D E, Hayes P C
Department of Hepatology, University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, UK.
Clinical Research Imaging Centre, Queen's Medical Research Institute, Edinburgh, UK.
Aliment Pharmacol Ther. 2016 May;43(9):947-54. doi: 10.1111/apt.13571. Epub 2016 Mar 7.
With advancing liver disease and the development of portal hypertension, there are major alterations in somatic and visceral blood flow. Using phase-contrast magnetic resonance angiography, we characterised alterations in blood flow within the hepatic, splanchnic and extra-splanchnic circulations of patients with established liver cirrhosis.
To compare blood flow in splanchnic and extra-splanchnic circulations in patients with varying degrees of cirrhosis and healthy controls.
In a single-centre prospective study, 21 healthy volunteers and 19 patients with established liver disease (Child's stage B and C) underwent electrocardiogram-gated phase-contrast-enhanced 3T magnetic resonance angiography of the aorta, hepatic artery, portal vein, superior mesenteric artery, and the renal and common carotid arteries.
In comparison to healthy volunteers, resting blood flow in the descending thoracic aorta was increased by 43% in patients with liver disease (4.31 ± 1.47 vs. 3.31 ± 0.80 L/min, P = 0.011). While portal vein flow was similar (0.83 ± 0.38 vs. 0.77 ± 0.35 L/min, P = 0.649), hepatic artery flow doubled (0.50 ± 0.46 vs. 0.25 ± 0.15 L/min, P = 0.021) and consequently total liver blood flow increased by 30% (1.33 ± 0.84 vs. 1.027 ± 0.5 L/min, P = 0.043). In patients with liver disease, superior mesenteric artery flow was threefold higher (0.65 ± 0.35 vs. 0.22 ± 0.13 L/min, P < 0.001), while total renal blood flow was reduced by 40% (0.37 ± 0.14 vs. 0.62 ± 0.22 L/min, P < 0.001) and total carotid blood flow unchanged (0.62 ± 0.20 vs. 0.65 ± 0.13 L/min, P = 0.315).
Rather than a generalised systemic hyperdynamic circulation, liver disease is associated with dysregulated splanchnic vasodilatation and portosystemic shunting that, while inducing a high cardiac output, causes compensatory extra-splanchnic vasoconstriction - the 'splanchnic steal' phenomenon. These circulatory disturbances may underlie many of the manifestations of advanced liver disease.
随着肝病进展和门静脉高压的发展，体循环和内脏血流发生重大改变。我们采用相位对比磁共振血管造影术，对已确诊肝硬化患者肝内、内脏和内脏外循环中的血流改变进行了特征分析。
比较不同程度肝硬化患者与健康对照者内脏和内脏外循环的血流情况。
在一项单中心前瞻性研究中，21名健康志愿者和19名已确诊肝病（Child B级和C级）的患者接受了心电图门控的相位对比增强3T磁共振血管造影，检查部位包括主动脉、肝动脉、门静脉、肠系膜上动脉、肾动脉和颈总动脉。
与健康志愿者相比，肝病患者胸降主动脉的静息血流增加了43%（4.31±1.47对3.31±0.80 L/min，P = 0.011）。虽然门静脉血流相似（0.83±0.38对0.77±0.35 L/min，P = 0.649），但肝动脉血流增加了一倍（0.50±0.46对0.25±0.15 L/min，P = 0.021），因此肝脏总血流量增加了30%（1.33±0.84对1.027±0.5 L/min，P = 0.043）。肝病患者的肠系膜上动脉血流增加了两倍（0.65±0.35对0.22±0.13 L/min，P < 0.001），而肾总血流量减少了40%（0.37±0.14对0.62±0.22 L/min，P < 0.001），颈总动脉总血流量无变化（0.62±0.20对0.65±0.13 L/min，P = 0.315）。
肝病并非伴有全身性高动力循环，而是与内脏血管扩张失调和门体分流有关，这在导致高心输出量的同时，引起内脏外血管的代偿性收缩——即“内脏盗血”现象。这些循环紊乱可能是晚期肝病许多表现的基础。
