Portal hypertension is the most important feature of liver cirrhosis and its complications. In addition, kidney dysfunction, especially renal vasoconstriction, plays important role in the hepatorenal syndrome and patient’s prognosis [
A total of 67 in-patients with liver cirrhosis were investigated from 2008 to 2010 year. The main characteristic of the patients with liver cirrhosis was given on Table
Characteristics of patients with liver cirrhosis.
Parameters | All patients |
Child A |
Child B |
Child C |
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Age ( |
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Sex—m/f | 39/28 | 17/16 | 14/8 | 8/4 |
Etiology ( |
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Alcohol | 25 | 5 | 10 | 10 |
Viral | 37 | 26 | 10 | 1 |
Study approved | 2 | 1 | 1 | — |
Autoimmune | 3 | 1 | 1 | 1 |
Others | ||||
LC ( |
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Compensated | 32 | 29 | 3 | 0 |
Decompensated | 35 | 4 | 19 | 12 |
Esophageal varices ( |
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Yes/no | 49/18 | 23/10 | 14/8 | 12/0 |
Ascites ( |
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Yes/no | 26/41 | 2/31 | 13/9 | 11/1 |
Encephalopathy ( |
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Yes/no | 8/59 | 0/33 | 2/20 | 6/6 |
MELD score ( |
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Therapy with ( |
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B-blockers—Yes/no | 39/28 | 15/18 | 16/6 | 8/4 |
Diuretics—Yes/no | 42/25 | 16/17 | 15/7 | 11/1 |
Comorbidity ( |
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Yes/no | 50/17 | 28/5 | 14/8 | 8/4 |
The study was approved by the Institutional Review Committee Board and informed consent for the trial was obtained from each person. The patients with gastrointestinal bleeding and or endoscopic band ligation or sclerotherapy in the last 8 weeks, surgery, thrombosis portal veins, liver tumors, extrahepatic cholestasis, acute alcoholic hepatitis, hepatorenal syndrome, therapy with vasoactive drugs, excluding beta-blockers and diuretics, significant concomitant disease and cotherapy, which might interfere Doppler ultrasound parameters, and renal function were excluded.
Abdominal ultrasound (US), as well as liver and renal Doppler US, was performed and interpreted by one investigator according to standard protocol. US measurements were done by Aloka SSD 4000, convex probe 2.5–5,0 MHz, cut-off filter 100 Hz, with angle of insonation 50°, using a 2–3,5-5 mm Doppler gate, as large as at least one-third of the vessel diameter. The investigated subjects fasted over night and rest in bed in the supine position for at least 10 minutes before the US measurements. Portal vein (PV), hepatic artery (HA), and intrarenal arteries (RAs), interlobar or segmental branch, were evaluated by Color Doppler US. A rectilinear segment of the common tract of the portal vein (PV), as near as possible to the bifurcation, was estimated. The proper hepatic artery (HA) was investigated near the point where it crosses the main PV. A train of at least three similar, sequential Doppler waveforms was obtained during suspended respiration, sometimes in sustained shallow inspiration. Three Doppler waveform tracings were obtained from each kidney by sampling the RA: right (RRA-RA) and left (LRA-RA) in the superior, middle, and inferior portions of the kidney. The mean values of the parameters, for each kidney, were obtained from the measurement of the waveforms of both, right and left renal area.
We evaluated the following hepatic and intrarenal blood flow Doppler parameters (cm/sec): PV peak systolic velocity (PV-PSV), portal venous time-averaged maximum velocity (PVV = PV-PSV × 0,57), HA maximum peak systolic velocity (HA-PSV), HA minimal end diastolic velocity (HA-EDV), HA mean velocity (HA-MnV = HA-PSV × 0,62), HA resistance index (HA-RI = HA-PSV − HA-EDV/HA-PSV), HA pulsatility index (HA-PI = HA-PSV − HA-EDV/HA-MnV), liver vascular index (LVI = PVV/HA-PI), modified liver vascular index (mLVI = PVV/HA-RI), arterio/portal ratio (A/P = HA-PSV/PV-PSV), RA peak systolic velocity (RA-PSV), RA minimal end diastolic velocity (RA-EDV), RA mean velocity (RA-MnV), RA resistance index (RA-RI = RA-PSV − RA-EDV/RA-PSV), and RA pulsatility index (RA-PI = RA-PSV − RA-EDV/RA-MnV).
The diagnosis of liver cirrhosis was based on standard criteria. Besides the standard hematological and biochemical tests, we also tested urine sodium excretion (mmol/24 h), glomerular filtration rate (GFR, mL/min), and correct GFR (GFR × 1,73/body surface, mL/min). For evaluation of the degree of liver damage we used Child-Pugh classification of liver cirrhosis [
Statistical analysis was performed using ANOVA, Mann-Whitney, and correlation analyses (SPSS v.14).
From all evaluated liver Doppler US parameters significant differences among Child’s class A, B, and C were observed only for the peak systolic velocity of PV, liver, and modified liver vascular indices (Table
Liver Doppler US parameters in patients with liver cirrhosis according to Child-Pugh classification.
Parameter | All patients |
Child A |
Child B |
Child C |
Child’s score (5–15 points) |
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Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Correlation ( | |
PVV |
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0.268,
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PV-PSV |
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0.268 |
HA-PSV |
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HA-MnV |
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HA-EDV |
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HA-RI |
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HA-PI |
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A/P |
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LVI |
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0.282
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mLVI |
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Liver Doppler US parameters with significant differences according to MELD score.
Parameter | MELD |
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Mean | SD | 95% confidence interval for mean | Minimum | Maximum |
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Lower bound | Upper bound | ||||||||
HA-MnV | <20 | 55 | 41.32 | 10.45 | 38.49 | 44.14 | 22.30 | 71.36 | 0.007 |
>20 | 12 | 52.01 | 18.29 | 40.39 | 63.62 | 24.37 | 84.60 | ||
HA-PSV | <20 | 55 | 66.49 | 16.85 | 61.93 | 71.04 | 36.00 | 115.10 | 0.007 |
>20 | 12 | 83.85 | 29.48 | 65.12 | 102.58 | 39.30 | 136.40 | ||
A/P | <20 | 55 | 2.41 | 0.63 | 2.24 | 2.58 | 1.15 | 4.07 | 0.029 |
>20 | 12 | 2.95 | 1.20 | 2.18 | 3.71 | 1.01 | 4.81 |
There were no significant differences between liver Doppler US parameters and the presence of esophageal varices and collaterals and among patients with compensated and decompensated liver cirrhosis, as well as patients with or without ascites, or portal encephalopathy.
All intrarenal blood flow Doppler parameters except right and left RA peak systolic velocity showed significant differences between Child’s class A, B, and C (Table
Renal Doppler US parameters in patients with liver cirrhosis according to Child-Pugh classification.
Parameter | All patients |
Child A |
Child B |
Child C |
Child’s score (5–15 points) |
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Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Correlation ( | |
RRA-PSV |
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LRA-PSV |
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RRA-MnV |
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LRA-MnV |
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RRA-EDV |
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LRA-EDV |
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RRA-RI |
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LRA-RI |
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RRA-PI |
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LRA-PI |
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According to MELD score a significant decrease of right and left RA mean velocity and minimal end diastolic velocity and an increase of right and left RA resistance and RA pulsatility indices were observed in patients with MELD <20 versus those with MELD >20 (Table
Renal Doppler US parameters in patients with liver cirrhosis according to MELD score.
Parameter | MELD |
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Mean | SD | 95% confidence interval for mean | Minimum | Maximum |
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MELD score (8–46) | |
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Lower bound | Upper bound | Correlation ( | ||||||||
<20 | 55 | 32.30 | 7.13 | 30.38 | 34.23 | 19.90 | 49.10 | |||
RRA-MnV | >20 | 12 | 28.47 | 7.88 | 23.46 | 33.47 | 13.80 | 39.90 | NS |
−0.396
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Total | 67 | 31.62 | 7.36 | 29.82 | 33.41 | 13.80 | 49.10 | |||
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<20 | 55 | 31.37 | 7.15 | 29.43 | 33.30 | 17.10 | 49.90 | |||
LRA-MnV | >20 | 12 | 29.89 | 9.73 | 23.71 | 36.08 | 14.90 | 53.50 | NS |
−0.294
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Total | 67 | 31.10 | 7.61 | 29.25 | 32.96 | 14.90 | 53.50 | |||
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<20 | 55 | 19.80 | 5.14 | 18.41 | 21.19 | 11.30 | 32.30 | |||
RRA-EDV | >20 | 12 | 15.71 | 5.46 | 12.24 | 19.18 | 6.80 | 24.20 | 0.016 |
−0.459
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Total | 67 | 19.07 | 5.40 | 17.75 | 20.39 | 6.80 | 32.30 | |||
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<20 | 55 | 18.51 | 4.75 | 17.22 | 19.79 | 10.20 | 30.70 | |||
LRA-EDV | >20 | 12 | 16.61 | 7.48 | 11.86 | 21.36 | 6.90 | 35.20 | NS |
−0.358
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Total | 67 | 18.17 | 5.33 | 16.87 | 19.47 | 6.90 | 35.20 | |||
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<20 | 55 | 0.65 | 0.05 | 0.63 | 0.66 | 0.56 | 0.79 | |||
RRA-RI | >20 | 12 | 0.73 | 0.07 | 0.68 | 0.77 | 00.65 | 0.86 | 0.0001 |
0.552
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Total | 67 | 0.66 | 0.06 | 0.65 | 0.68 | 0.56 | 0.86 | |||
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<20 | 55 | 0.66 | 0.06 | 0.64 | 0.67 | 0.53 | 0.77 | |||
LRA-RI | >20 | 12 | 0.74 | 0.07 | 0.69 | 0.78 | 0.61 | 0.82 | 0.0001 |
0.477
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Total | 67 | 0.67 | 0.07 | 0.66 | 0.69 | 0.53 | 0.82 | |||
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<20 | 55 | 1.13 | 0.17 | 1.08 | 1.17 | 0.87 | 1.57 | |||
RRA-PI | >30 | 12 | 1.56 | 0.47 | 1.27 | 1.86 | 1.13 | 2.62 | 0.0001 |
0.604
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Total | 67 | 1.21 | 0.30 | 1.13 | 1.28 | 0.87 | 2.62 | |||
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<20 | 55 | 1.16 | 0.19 | 1.11 | 1.22 | 0.78 | 1.78 | |||
LRA-PI | >30 | 12 | 1.56 | 0.35 | 1.33 | 1.78 | 1.01 | 2.22 | 0.0001 |
0.564
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Total | 67 | 1.23 | 0.27 | 1.17 | 1.30 | 0.78 | 2.22 |
In patients with esophageal varices we observed a decrease of right (
The values of RRA/LRA-MnV, RRA/LRA-PSV and RRA/LRA-EDV in patients with presence or absence of esophageal varices.
In comparison of patients with compensated and decompensated liver cirrhosis we found a significant decrease of right RA minimal end diastolic velocity (
The values of RRA/LRA-EDV in patients with compensated and decompensated liver cirrhosis.
The values of RRA/LRA-RI in patients with compensated and decompensated liver cirrhosis.
The values of RRA/LRA-PI in patients with compensated and decompensated liver cirrhosis.
The values of RRA/LRA-MnV and RRA/LRA-EDV in patients with presence or absence of ascites.
The values of RRA/LRA-RI in patients with presence or absence of hepatic encephalopathy.
The values of RRA/LRA-PI in patients with presence or absence of hepatic encephalopathy.
We observed correlations between Doppler US parameters of hepatic artery and arterio/portal ratio by one hand and some renal Doppler US parameters on the other hand (Table
Significant correlations between liver and renal Doppler US parameters.
Surrogate markers of renal function | Parameters | Pearson correlation |
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RRA-MnV | 0.252 | 0.040 | |
HA-PSV | RRA-PSV | 0.347 | 0.004 |
LRA-PSV | 0.363 | 0.003 | |
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RRA-MnV | 0.250 | 0.041 | |
HA-MnV | RRA-PSV | 0.343 | 0.005 |
LRA-PSV | 0.355 | 0.003 | |
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RRA-MnV | 0.278 | 0.023 | |
LRA-MnV | 0.266 | 0.030 | |
HA-EDV | RRA-EDV | 0.301 | 0.013 |
RRA-EDV | 0.287 | 0.019 | |
LRA-PSV | 0.267 | 0.029 | |
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RRA-RI | 0.446 | 0.0001 | |
LRA-RI | 0.528 | 0.0001 | |
HA-RI | RRA-PI | 0.387 | 0.001 |
LRA-RI | 0.451 | 0.001 | |
LRA-EDV | −0.250 | 0.041 | |
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RRA-PSV | 0.244 | 0.047 | |
RRA-RI | 0.416 | 0.0001 | |
HA-PI | LRA-RI | 0.477 | 0.0001 |
RRA-PI | 0.344 | 0.004 | |
LRA-RI | 0.394 | 0.001 | |
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A/P | RRA-PSV | 0.284 | 0.020 |
Serum urea levels and serum sodium levels correlated with Child’s and MELD scores (Table
Significant correlations between surrogate markers of renal function and Childs and MELD scores, and renal Doppler US parameters.
Surrogate markers of renal function | Parameters | Pearson correlation |
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Serum urea | Child’s score | 0.353 | 0.012 |
MELD score | 0.435 | 0.002 | |
LRA-MnV | −0.294 | 0.036 | |
LRA-EDV | −0.313 | 0.025 | |
RRA-RI | 0.297 | 0.035 | |
RRA-PI | 0.296 | 0.035 | |
LRA-PI | 0.280 | 0.046 | |
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Serum creatinine | RRA-MnV | −0.346 | 0.005 |
LRA-MnV | −0.326 | 0.008 | |
RRA-EDV | −0.350 | 0.004 | |
LRA-EDV | −0.317 | 0.010 | |
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Serum sodium | Child’s score | −0.423 | 0.001 |
MELD score | −0.485 | 0.0001 |
We observed relationship between patient’s age and some liver Doppler US parameters as HA minimal end diastolic velocity
Many liver Doppler US parameters and indices have been used to distinguish the patients with portal hypertension from those with normal hemodynamic of portal vein and hepatic arterial blood flow [
The evaluation of the renal hemodynamics in patients with liver cirrhosis is based mainly on the index of resistance of the intrarenal arteries [
The simultaneous measurement of liver and renal Doppler US parameters allows to find relationships between Doppler US parameters of hepatic artery and the corresponding renal artery Doppler US parameters. These data emphasize common pathophysiological mechanisms for impairment of hepatic and renal artery blood flow. On the other hand, renal Doppler US parameters show more dynamic deviations than liver Doppler US parameters in advance of liver cirrhosis and may need to be evaluated in follow-up of these patients.
In conclusion, our results show parallel changes in renal and hepatic artery Doppler US parameters in patients with liver cirrhosis, independently of patient’s age. There is no direct correlation between the degree or complications of liver cirrhosis and most of liver Doppler US parameters. In contrast, renal Doppler US parameters correlate with the severity and complications of liver cirrhosis. Because of dynamic deviations of renal Doppler US parameters in advance of liver cirrhosis, we recommend Doppler US of renal artery as a part of the followup of these patients.