| Background: Portal hypertension is the most frequent clinical manifestation of cirrhosis. Predictive criteria for a first variceal hemorrhage and rebleeding is very important. Variceal pressure (VP) might be more relevant to variceal hemorrhage than the measurements of the hepatic venous pressure gradient (HVPG); the Jatter aJso has the disadvantage of being an invasion technique. Direct endoscopic puncture of the varices is the most exact method for assessment of variceal pressure, but the technique is not without risk because it may cause bleeding. Therefore, the method is in general restricted to patients under-going sclerotherapy. In 1980s noninvasive measurement is possible using a endoscopic pressure-sensitive gauge. Noninvasive techniques are based on the concept that the pressure required to compress the varix equals the VP. Ideal position of the gauge on varices proved to be difficult, and it is reproducible only in expert hands. Based on the disadvantage of endoscopic gauge technique, Gertsch and co-workers recently showed a non-invasive endoscopic balloon technique, which is a safe.easy and reproducible method for estimating VP in patients with portal hypertension. However,the new balloon technique is not yet used in dometic.Many drugs have been shown to reduce portal pressure in man. Among them, propranolol is the most and ,until recently, the only drugs used to prevent variceal hemorrhage. Propranolol is given orally with doses adjusted for each patient according to heart rate. In general, the dose is increased until the heart rate decreases by 25%, but not below 55 beats/min. However, there is extensive first-pass metabolism of propranolol in the liver, so that the plasma propranolol concentration is significantdifference among patients with the same dosage, especially with cirrhosis.Objective: The feasibility and reliability of a noninvasive endoscopic balloon technique for measurement of esophageal varix pressure was evaluated. In addition, high-performance liquid chromatographic(HPLC) method for the determination of proranolol in serum was established, and the correlation was assessed between propranolol concentration and heart rate in patients with cirrhosis.Method: Using an in vitro model consisting of an artificial esophagus(plastic tube) containing a water-filled latex tube(varix), the correlation was evaluated between actual pressure in latex tube and measured pressure by balloon technique. The variceal pressure was measured by endoscopic balloon technique in 37 patients with portal hypertension, these measurements were correlated between two investigators as well as parameters to predict the individual risk of variceal bleeding. In addition, the HPLC detection of proranolol was in 12 patients with cirrhosis, and we studied the relationship between changes of heart rate and serum level of propranolol.Statistical Analyses: Analyses of variables were calculated by SPSS8.0 program. Correlation between two groups was performed by simple linear regression and correlation analysis. Correlation coefficient (r) was evaluated by Student' s t-test.Results: In vitro, the influence of the latex tube diameter(4, 5, 6mm) and wall thickness(l, 1.5mm) were investigated, linear regression analysis showed a good correlation between the pressure in the latex tube made of different materials and that measured endoscopically(r> 0.839), the latter also well correlated with the variceal pressure detected by transducer(r=0.924). Determination of variceal pressure was successful in 32/37 patients, while no side effects were observed. The intraobservercoefficient of variation was 6.79 ?.56%, and there was a significant(p<0.001) correlation between the investigators (r =0.938). Portal pressure correlated to variceal pressure(r=0.889) in 4/37 patients with portosystemic devascalarization. Variceal pressures were significantly higher in patients with red color sign and/or with a history of variceal bleeding than that of other groups (p<0.01), but the Child-Pugh score did not correlate with v...
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