Portal Hypertension and Esophageal Varices in Cystic Fibrosis: Unreliability of Echo-Doppler Flowmetry

To investigate the role of echo-Doppler flowmetry in evaluating patients with cystic fibrosis and portal hypertension at risk of esophageal varices, we studied 26 subjects divided in 3 groups: 9 with portal hypertension and esophageal varices, 8 with chronic liver disease without varices, and 9 without chronic liver disease. Spleen size, diameter, blood velocity, and flow rate of portal, splenic, and superior mesenteric veins were recorded. In patients without chronic liver disease Doppler measurements were repeated on 2 different days to assess intraobserver variability. Significant differences among the three groups were found for mean values of spleen size and diameters of portal, splenic, and superior mesenteric veins. Nevertheless, a considerable overlapping of individual data was observed. No differences were observed in mean hemodynamic measurements, except for blood velocity in portal vein and flow rate in splenic vein. The intraobserver variability for repeated Doppler measurements was clinically unacceptable for most of the variables studied. Echo-Doppler assessment of splanchnic flow seems to be an unreliable tool in the management of cystic fibrosis patients with portal hypertension at risk of esophageal varices.     

Hepatic radionuclide angiography and Doppler ultrasonography in the detection and assessment of vascular disturbances in the portal system

BACKGROUND/AIMS: The aim of the study was evaluation of the morphology of the blood vessels, blood flow velocity and direction with Doppler ultrasound (D-US) and correlation with the relative liver parenchymal perfusion assessed by hepatic radionuclide angiography (HRA). METHODOLOGY: Real-time, D-US and HRA were performed in 108 patients. RESULTS: In patients with portal venous aneurysm, hepatopetal blood flow was increased, while portal perfusion did not differ from controls. In portal hypertensive patients, D-US detected dilatation of the portal system veins, with decreased blood flow. In comparison to the portal perfusion in controls and portal venous aneurysm, values were significantly (p < 0.01) lower in chronic active hepatitis and liver cirrhosis and differed between themselves (p < 0.01). In the groups of cirrhotic patients with esophageal varices, sclerosed esophageal varices, recanalized umbilical vein, partial portal thrombosis and cavernous portal vein with hepatofugal, hyperkinetic or slow blood flow, and very low velocities beside the thrombi, portal perfusion was lower (p < 0.01) than in controls, portal venous aneurysm, chronic active hepatitis and liver cirrhosis without collaterals. In complete thrombosis, minimal collateral flow was found with D-US, while HRA proved no portal supply. CONCLUSIONS: D-US and HRA are complementary for the estimation of various liver vascular disorders.     

Evaluation of the effects of combined endoscopic variceal ligation and splenectomy with pericardial devascularization on esophageal varices

INTRODUCTION In patients with portal hypertension, collaterals should be established to reduce the high portal pressure, and the hemodynamic indicators of such collaterals have been used for the evaluation of therapeutic effects. According to the location…     

Portal hemodynamics in patients with gastric varices. A study in 230 patients with esophageal and/or gastric varices using portal vein catheterization

The hemodynamic features of gastric varices are not well documented. The purpose of this study was to investigate the nature of hepatofugal collateral veins, their origins, the direction of blood flow in the major veins and collateral veins, and portal venous pressure. To this end, 230 patients, mostly cirrhotic, who had esophageal or gastric varices, or both, demonstrated by endoscopy were investigated by portal vein catheterization. The findings were correlated with endoscopically assessed degrees of varices. Gastric varices were seen in 57% of the patients with varices due to portal hypertension. In most of the patients with advanced gastric varices, esophageal varices were minimal or absent. When patients with gastric varices were compared with those having predominantly esophageal varices, it was found that advanced gastric varices were more frequently supplied by the short and posterior gastric veins, they were almost always associated with large gastrorenal shunts, and portal venous pressure in patients with large gastric varices was lower. Chronic portal systemic encephalopathy was more common in patients with large gastric varices due to hepatofugal flow of superior mesenteric venous blood in the splenic vein than in patients with predominantly esophageal varices. Thus, the hemodynamics in patients with large gastric varices are distinctly different from those in patients with mainly esophageal varices, and such differences seem to account for the differing incidence of chronic encephalopathy and variceal bleeding.     

Endoscopic, Ultrasonographic, and US-Doppler Parameters as Indicators of Variceal Bleeding in Patients with Schistosomiasis

Bleeding from esophagogastric varices is a potentially deadly complication in patients with hepatosplenic schistosomiasis. The aim of this study is to establish indicators of variceal bleeding. We studied 40 patients with compensated hepatosplenic schistosomiasis and varices, analyzing four endoscopic (variceal size, red color signs, fundic varices, and congestive gastropathy), nine ultrasonographic (right and left hepatic lobe size, periportal and gallbladder wall thickness, portal and splenic veins diameter, spleen longitudinal axis and volume, and presence of collateral circulation), and five US-Doppler parameters (portal and splenic veins velocity and flow and portal vein congestion index). Patients were divided in two groups according to previous history of variceal bleeding. The group with bleeding episodes was again divided in two groups: with and without treatment, namely endoscopic sclerotherapy. All endoscopic parameters and two ultrasonographic (periportal thickness and portal vein diameter) were statistically different between the groups with and without previous bleeding. The likelihood index, adopted to determine the best parameters related to previous bleeding showed that the most important combinations are: gastropathy and red signs followed by portal vein diameter and variceal size. In conclusion, although aware of the limits of the statistical analysis due to the small number of patients, our results demonstrated that endoscopic and US parameters (isolated or combined) can identify patients with a high risk of variceal bleeding, allowing physicians to optimize prophylactic therapy.     

Clinical Utility of Pulsed Doppler Flowmetry in Patients with Portal Hypertension

The recently developed Doppler flowmetry system that consists of an electronic sector and a pulsed Doppler flowmeter, is capable of determining the direction of blood flow in large veins visible by ultrasonography and measuring blood flow. It is noninvasive and can be performed in patients on ambulatory basis at the time of routine ultrasound examination. In this communication, clinical utility of pulsed Doppler flowmetry was tested in 20 patients with portal hypertension. Doppler flowmetry proved useful in differential diagnosis of splenorenal shunt and cystic disease, diagnosis of arterioportal shunt, diagnosis of portal vein occlusion, demonstration of hepatofugal flow in the splenic vein, and prediction of esophageal varices by the demonstration of hepatofugal flow in an enlarged left gastric vein.     

Effect of propranolol on portosystemic collateral circulation in patients with cirrhosis

Propranolol has been demonstrated to be effective in lowering portal pressure in cirrhotic patients. This effect is mediated by a reduction of splanchnic arterial inflow and a consequent decrease of portal vein and portocollateral blood flow. Although experimental studies suggest a direct effect of the drug on portocollateral circulation, little information exists about relative flow changes occurring in the portal vein and in collateral veins feeding esophageal varices. This study addressed the problem in 12 cirrhotic patients selected on the basis of feasibility of Doppler flowmetry in both the portal and left gastric veins. Caliber, flow velocity and flow volume in both vessels were measured by Doppler ultrasound before and at 60, 120 and 180 min after an oral dose of 40 mg propranolol, together with heart rate and mean arterial pressure. A significant decrease in heart rate (-17.6% +/- 1.1%, p less than 0.001) and mean arterial pressure (-10.6% +/- 0.9%, p less than 0.005) confirmed effective beta-blockade. Baseline flow velocity was significantly lower in the portal vein than in the left gastric vein (12.4 +/- 0.6 vs. 15.4 +/- 1.5 cm/sec, p less than 0.05). Maximal hemodynamic effect was reached at 120 min after administration of propranolol. The vessel caliber did not change significantly. Flow velocity fell from 12.4 +/- 0.6 to 10.4 +/- 0.7 cm/sec in the portal vein (p less than 0.05) and from 15.4 +/- 1.5 to 11.1 +/- 0.9 cm/sec in the left gastric vein (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Endoscopic recurrence of esophageal varices is associated with the specific EUS abnormalities: severe periesophageal collateral veins and large perforating veins

BACKGROUND: Endoscopic ultrasonography (EUS) with a 20 MHz ultrasound (US) catheter probe can clearly demonstrate esophageal collateral veins. The presence of large periesophageal collateral veins has been correlated with large esophageal varices in patients with portal hypertension. The correlation between the size of esophageal collateral veins and endoscopic recurrence of esophageal varices in patients with portal hypertension who had undergone endoscopic injection sclerotherapy was investigated. Furthermore, whether EUS findings could predict the variceal recurrence was retrospectively studied. METHODS: Thirty-eight patients who had undergone endoscopic injection sclerotherapy were examined every 3 to 4 months with endoscopy and US catheter probe for a period of 2 years. Recurrence of esophageal varices was determined by endoscopic findings of either new varix formation or appearance of red color sign. Esophageal collateral veins were identified by US catheter probe as peri-esophageal collateral veins (adjacent to the esophageal wall) and para-esophageal collateral veins (separated from the esophageal wall) along with perforating veins; and they were graded as severe and mild type by US catheter probe. RESULT: Ten of the 38 patients (26.3%) had endoscopic recurrence at a mean of 10.9 months after endoscopic injection sclerotherapy. In patients with endoscopic recurrences, EUS findings included a significantly (p < 0.001) higher incidence of severe type peri-esophageal collateral veins, a significantly larger number of perforating veins (p < 0.001) and a significantly larger diameter of perforating veins (p < 0.001) compared with patients without recurrence (8 of 10, 80% vs. 2 of 28, 7.1%; 1.30 vs. 0.21; 2.00 vs. 0.32 mm, respectively). The presence of veins at the esophagogastric junction did not correlate with recurrence. CONCLUSION: Severe type peri-esophageal collateral veins and large perforating veins of the esophagus detected by EUS in patients treated by endoscopic injection sclerotherapy signify recurrence of esophageal varices and predict endoscopic recurrence of varices in subsequent months.     

肝硬化食道静脉曲张的门脉血流动力学改变及相关参数的研究分析

目的通过探讨乙肝肝硬化食道静脉曲张患者的门脉血流动力学改变,遴选敏感预测食道静脉曲张程度的相关彩色多普勒指标。方法肝硬化组80例,对照组30例,均经内镜检查,将食道静脉曲张程度分为轻、中、重度。彩色多普勒超声（CDFI）测定门静脉主干（PV）、脾静脉（SV）、肠系膜上静脉（SMV）及胃左静脉（LGV）四条静脉血管内径（D,cm）、平均血流速度（V,cm/min）,血流量（Q,ml/min）。结果 1.肝硬化组VPV、VSV、VSMV较对照组明显减低、VLGV的流速较对照组明显增快,DPV、DSV、DSMV、DLGV较对照组增宽,Qsv、Qpv、QLGV、QSMV均较对照组明显增多,肝硬化组Qsv/Qpv为54.5%,高于对照组的30.3%。2.随食道静脉曲张程度的加重,DPV逐渐增加、VPV逐渐下降、DLGV、VLGV、QLGV均明显增加,重度组均可见＂红色征＂,其中（＋＋）者为92.3%（36/39）。3.对照组LGV血流均呈向肝型,在肝硬化组中可见向肝、离肝、双向三种血流方向,肝硬化组中81.25%为离肝型血流,5%为双向型血流,13.75%为向肝型血流,其中重度组的离肝型血流比例高达94.9%。结论肝硬化门脉高压时PV、SV、SMV及LGV的血流动力学均有明显的改变,可作为判断食道静脉曲张程度的敏感、无创性诊断指标,其中LGV血流动力学指标在判断重度食道静脉曲张方面具有更重要的临床价值。     

The effect of endoscopic injection sclerotherapy on portal blood flow and liver function

BACKGROUND/AIMS: It is still controversial whether endoscopic injection sclerotherapy can affect portal blood flow and liver function. To clarify this issue, we investigated the change in portal blood flow velocity and the relationship between liver function and portal blood flow after sclerotherapy. METHODOLOGY: Ten liver cirrhosis patients with F2 esophageal varices were enrolled in this study. All patients underwent sclerotherapy until all varices were eradicated. Portal blood flow velocity was measured using Doppler ultrasonography. The changes in laboratory parameters and the portal flow velocity were analyzed in each patient. RESULTS: Total mean portal blood flow velocity was changed from 7.5 +/- 5.3 cm/s to 10.3 +/- 3.5 cm/s by sclerotherapy. Six of ten cases had increase in portal blood flow velocity. Among them, 5 cases demonstrated improvement in serum albumin and total cholesterol level 3 months after sclerotherapy. CONCLUSIONS: Prophylactic endoscopic injection sclerotherapy among patients with early liver cirrhosis can improve liver function by increasing the portal blood flow.     

Utility of endoscopic ultrasound in patients with portal hypertension

Endoscopic ultrasound(EUS) has revolutionized the diagnostic and therapeutic approach to patients with gastrointestinal disorders. Its application in patients with liver disease and portal hypertension is increasing. Patients with chronic liver disease are at risk for development of portal hypertension sequale such as ascites, spontaneous bacterial peritonitis and gastroesophageal varices. Bleeding esophageal and gastric varices are among the most common causes of mortality in patients with cirrhosis. Thus, early detection and treatment improve the outcome in this population. EUS can improve the detection and diagnosis of gastroesophageal varices and collateral veins and can provide endoscopic therapy of gastroesophageal varices such as EUS-guided sclerotherapy of esophageal collateral vessels and EUS-guided cynoacrylate(Glue) injection of gastric varices. EUS can also provide knowledge on the efficacy of pharmacotherapy of portal hypertension. Furthermore, EUS can provide assessment and prediction of variceal recurrence after endoscopic therapy and assessment of portal hemodynamics such as E-Flow and Doppler study of the azygous and portal veins. Moreover, EUS-guided fine needle aspiration may provide cytologic diagnosis of focal hepatic tumors andanalysis of free abdominal fluid.Using specialized EUSguided needle biopsy,a sample of liver tissue can be obtained to diagnose and evaluate for chronic liver disease.EUS-guided fine needle injection can be used to study portal vein pressure and hemodynamics,and potentially could be used to assist in exact measurement of portal vein pressure and placement of intrahepatic portosystemic shunt.     

Correlation of Doppler ultrasound of the portal system with endoscopic changes caused by portal hypertension in cirrhotic patients

BACKGROUND: The portal hypertension in cirrhotic patients is the main cause of this illness complication, that are clinically translated to visible collateral circulation in the abdominal wall, ascites and esophageal varices. AIM: To evaluate if the portal system echodoppler is able to estimate the presence of esophageal varices, gastric varices and congestive gastropathy in patients with hepatic cirrhosis. PATIENTS AND METHODS: One hundred and eighty six patients of the gastroenterology and hepatology ambulatory of the Clinical Hospital of the Federal University of Paraná, Curitiba, PR, Brazil, had been selected for evaluation. Of those, 145 had completed all the stages of the evaluation and 133 had been enclosed in the final analysis. All had been submitted to high digestive endoscopy for evaluation of esophagogastric varices and congestive gastropathy and then to Doppler ultrasound of the portal system with study of the systolic peak speed of the portal vein, diameter of the portal and splenic vein and spleen size, presence of the umbilical vein recanalization and hepatofugal flow. RESULTS: The patients with esophagogastric varices had significant difference of the spleen size when compared to patients without these change. However, none of the Doppler ultrasound parameters showed good accuracy and specificity in this group of cirrhotic patients. Congestive gastropathy patients had their diagnosis predict with significant manner not only by the portal and splenic vein diameter but also by the spleen size. Similarly to that described above, they do not have a good accuracy and specificity. These evaluations were validated by the construction of ROC (Receiver Operating Characteristic) curves, whose areas below the curves had always been less than 0,8. CONCLUSION: There was not a good correlation of the Doppler ultrasound parameters of the portal system to the presence of the main endoscopic alterations (esophagogastric varices and congestive gastropathy) in patients with hepatic cirrhosis.     

肝硬化非常见侧支循环临床特点研究

目的 探讨肝硬化患者门体循环之间非常见侧支循环形成的临床特点及意义。方法 对临床确诊为肝硬化的患者运用64排螺旋CT和三维血管成像结合电子胃镜检查,观察其门体循环之间非常见侧支循环的形成。结果 ①700例肝硬化患者中118例(16.86%)存在非常见侧支循环,依次为脾肾静脉分流、胃肾静脉分流、椎旁静脉分流、腹膜后静脉分流、胃脾分流和心膈角静脉分流。②非常见侧支循环形成与肝硬化Child-Pugh分级相关(P<0.01)。③与常见侧支循环形成组比较,非常见侧支循环组较少出现重度食管和(或)胃底静脉曲张、重度门静脉高压性胃病及大量腹水(P<0.01)。④非常见侧支循环组中肝性脑病和慢性血氨升高的发生率高于常见侧支循环组(P<0.01)。结论 ①肝硬化患者中非常见侧支循环并不"非常见";②非常见侧支循环形成与肝功能Child-Pugh分级有关;③非常见侧支循环形成可缓解门静脉高压引起的相关并发症,但增大了肝性脑病和慢性血氨升高的发病率。     

Collateral vessels around the esophageal wall in patients with portal hypertension: comparison of EUS imaging and microscopic findings at autopsy

BACKGROUND: In patients with portal hypertension, EUS reveals the presence of collateral vessels within and outside the esophageal wall such as esophageal varices, periesophageal collateral veins (peri-ECVs), paraesophageal collateral veins (para-ECVs), and perforating veins. This study retrospectively compared radial EUS images of these collateral vessels with histopathologic findings. METHODS: Four patients with esophageal varices treated by endoscopic injection sclerotherapy were studied. EUS was performed to evaluate the effects of endoscopic injection sclerotherapy. After endoscopic injection sclerotherapy, the segment of the esophagus from the esophagogastric junction to a point 5 cm proximal to junction was imaged with a 20-MHz radial scanning catheter US probe. Esophageal collateral veins outside the esophageal wall were identified as peri-ECVs (veins lateral to muscularis propria or within adventitia) and para-ECVs (veins lateral and separate from muscularis propria) along with perforating veins (veins connecting extramural collateral veins to submucosal varices). At autopsy, the esophagus with surrounding tissue was removed and cross-sectioned at 1-cm intervals from the esophagogastric junction to a point 5 cm proximal to the junction. Radial EUS images were correlated with histopathologic findings. RESULTS: Radial EUS after endoscopic injection sclerotherapy demonstrated peri-ECVs and perforating veins in all cases and para-ECVs in 3 cases. Based on histopathologic findings, veins associated with the esophageal wall were divided into 3 groups: those adjacent to the muscularis propria, veins separated from the wall without contact with the muscularis propria, and veins perforating the muscularis propria. All 3 groups of veins were observed in all cases. These 3 types of veins identified by histopathologic examination corresponded, respectively, to the peri-ECVs, para-ECVs, and perforating veins observed by EUS. CONCLUSION: Collateral esophageal veins demonstrated by radial EUS in patients with portal hypertension correspond to collateral veins identified histopathologically. In patients with portal hypertension, EUS is useful for assessment of vascular anatomy around the esophageal wall.     

Extensive portal and splenic vein thrombosis: differences in hemodynamics and management

BACKGROUND/AIMS: To assess the incidence of extensive portal and splenic vein thrombosis in patients with extrahepatic portal vein obstruction and determine the differences in presentation, portal hemodynamics and management as compared to patients with portal vein thrombosis alone. METHODOLOGY: 118 patients of extrahepatic portal vein obstruction presenting with variceal hemorrhage, having received no definitive treatment prior to presentation were divided into two groups--with portal and splenic vein thrombosis and with portal vein thrombosis, based on ultrasonography and splenoportography. Collateralization patterns on splenoportography were studied. Results of endoscopic variceal sclerotherapy were compared. RESULTS: Portal and splenic vein thrombosis was seen in 39 patients. Collateralization in case of portal and splenic vein thrombosis, in contrast to portal vein thrombosis, was predominantly left sided (74% vs. 9%, p < 0.0001). Fundal gastric varices were seen more often in patients with portal and splenic vein thrombosis (28% vs. 11%, p = 0.02), developing even after variceal obliteration, though obliteration was achieved in fewer sessions. Surgery for control of variceal bleed was performed more in the portal and splenic vein thrombosis group (33% vs. 15%, p = 0.02), especially for gastric varices (28% vs. 9%, p = 0.006). CONCLUSIONS: Portal and splenic vein thrombosis is present in 33% of patients with extrahepatic portal vein obstruction. Hemodynamic patterns differ, accounting for the preponderance of gastric varices on presentation in patients with portal and splenic vein thrombosis and an increased need for surgery.     

Effects of vasopressin on left gastric venous flow in cirrhotic patients with esophageal varices

To assess vasopressin control of esophageal variceal bleeding, we investigated the effect of vasopressin on the left gastric venous flow, portal venous flow, superior mesenteric venous flow, and splenic venous flow in seven cirrhotic patients with esophageal varices, using a duplex system consisting of a real-time ultrasonograph and an echo-Doppler flowmeter. Infusion of vasopressin (0.3 U/min) significantly decreased the blood flow in the left gastric vein (-56%), portal trunk (-54%), superior mesenteric vein (-54%), and splenic vein (-56%) as a result of decrease of blood velocity in these vessels. Thus, vasopressin seems to control esophageal variceal bleeding, in part, by reducing blood velocity and blood flow in the left gastric vein following reduction of blood velocity and blood flow in the superior mesenteric vein and splenic vein.     

Hepatofugal flow on computed tomography of arterial portography: its correlation with esophageal varices bleeding

BACKGROUND/AIMS: To study the portal flow patterns from CTAP (computed tomography of arterial portography), then to predict the existence of esophageal varices bleeding clinically. METHODOLOGY: 192 patients who underwent CTAP from superior mesenteric artery infusion were recruited in this study. The obtained images were classified according to our proposed criteria. Stage 0: hepatopetal flow, when all the contrast medium from the superior mesenteric vein entered the portal vein. Stage 1: when the contrast medium opacified the splenic vein or the other collateral vessels. Stage II: when the contrast medium opacified the paraesophageal vessels without entering the inner wall of the esophagus. Stage III: when the contrast medium opacified the collaterals up to the inner wall of the esophagus. RESULTS: The incidence of bleeding esophageal varices was correlated to the different stages of collateral flows pattern obtained. The esophageal varices bleeding rates were 0/137, 1/16, 1/14, 16/25 for stage 0, I, II and III, respectively. The incidence of bleeding esophageal varices was significantly higher in stage III group than in the other groups (P < 0.001). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of stage III patients in regard to the occurrence of bleeding esophageal varices were estimated as 80.0%, 98.8%, 88.9%, 94.8%, and 94.3%, respectively. CONCLUSIONS: Our results show that CTAP demonstrates the portal flow patterns and collateral veins clearly, which can serve as an excellent imaging modality to predict the risk of esophageal varices bleeding.     

Effect of release‐controlled nifedipine on portal hemodynamics in cirrhotic patients

OBJECTIVE : To evaluate the therapeutic effect of release‐controlled nifedipine on portal hypertension. METHODS : Thirty‐two cirrhotic patients were enrolled to investigate, by using duplex Doppler ultrasonography, differences in portal hemodynamics before and after treatment with release‐controlled nifedipine (30 mg once per day). RESULTS : After taking nifedipine, the diameter, blood velocity and blood flow of the portal vein decreased, but only the change in velocity was statistically significant. After treatment, the congestion index increased, and the blood velocity and blood flow of the splenic vein significantly decreased. The resistance and pulsatile indices of the right hepatic and splenic arteries also decreased markedly. The total hepatic blood flow was elevated slightly and there were no significant changes in mean arterial pressure and heart rate. CONCLUSIONS : The resistance and pulsatile indices of the hepatic and splenic arteries are representative indices of portal resistance. Release‐controlled nifedipine may decrease portal pressure by the following mechanisms: (i) decrease of systemic blood pressure triggers the sympathetic reflex, leading to splanchnic artery constriction and portal blood flow reduction; (ii) dilatation of the portal vein and sinusoids leads to decrease portal resistance; and (iii) dilatation of the collateral veins. Nifedipine has no significant effect on systemic circulation in normotensive cirrhotic patients, therefore it has good prospects as a drug for clinical use in portal hypertension.     

Portal vein thrombosis following sclerotherapy.

We present the case of a woman with idiopathic portal hypertension who underwent sclerotherapy for bleeding esophageal varices. She had a rebleed 27 months after complete eradication of esophageal varices. Endoscopy showed bleeding gastric varices. Ultrasonography, and later splenoportography, revealed a large thrombus in the right branch of the portal vein causing gross dilation of the portal and splenic vein. A proximal splenorenal shunt was done to decompress the portal system and hence gastric varices. Repeat endoscopy 4 weeks after surgery revealed complete disappearance of the gastric varices, while ultrasonography at 38 weeks showed marked decompression of the portal system with complete disappearance of the thrombus from the right branch of the portal vein. No new thrombus formation was seen.     

Portal hemodynamics in chronic portal-systemic encephalopathy. Angiographic study in seven cases

A portal hemodynamic study was made in 7 consecutive patients with chronic portal-systemic encephalopathy by percutaneous transhepatic catheterization of the portal vein and injecting contrast medium into the superior mesenteric vein or by superior mesenteric arterial portography in comparison with patients without encephalopathy studied by percutaneous catheterization of these veins. All 7 patients had a large gastro-renal or spleno-renal shunt, and a large proportion of superior mesenteric venous blood was being shunted as estimated from the diameter of the portal and the collateral vein, whereas in nonencephalopathic patients in whom part of the superior mesenteric venous blood was shunting this diversion was much less (P less than 0.001). Only one of the chronic portal-systemic encephalopathic patients had esophageal varices, insignificant in size, and the incidence of esophageal varices was significantly less compared to the 12 nonencephalopathic control patients with portal hypertension who had either a gastro-renal or spleno-renal shunt (P less than 0.05). It is suggested that chronic portal-systemic encephalopathy is a result of a large collateral route shunting a large proportion of the superior mesenteric venous blood into systemic circulation, and that development of such collaterals precludes formation of large esophageal varices.