Portal hemodynamics in cirrhotics with portal hypertension using color Doppler velocity profile.

OBJECTIVE

To investigate portal hemodynamics and its correlation with esophageal variceal bleeding (EVB) in cirrhotics with portal hypertension by using a newly-developed technique, color Doppler velocity profile (CDVP).

METHODS

Hemodynamics of portal trunk (PT), right anterior branch (RAB) and splenic vein (SV) were evaluated in 48 cirrhotics with portal hypertension and 35 normal volunteers by CDVP. The parameters included maximum cross-sectional velocity (CS-Vmax), flow volume, congestion index (CI), profile parameter N and pattern of flow curve. Stepwise logistic regression model was employed to determine EVB-relating factors in cirrhotics.

RESULTS

CS-Vmax in PT and RAB was significantly lower in cirrhotic group than that of normal group, being 14.91 +/- 3.08 cm/s, 9.44 +/- 2.70 cm/s vs 30.52 +/- 6.75 cm/s, 12.82 +/- 2.69 cm/s, respectively (P < 0.01 for both). Flow volume of PT and SV was significantly higher in cirrhotic group compared with that of normal group, being 25.16 +/- 10.48 ml.min-1.kg-1, 15.83 +/- 9.18 ml.min-1.kg-1 vs 20.43 +/- 5.57 ml.min-1.kg-1, 5.81 +/- 2.04 ml.min-1.kg-1, respectively (P < 0.01 for both). CI of PT, RAB and SV was significantly higher in cirrhotic group than in normal group, being 0.142 +/- 0.0654, 0.105 +/- 0.0496, 0.0884 +/- 0.0431 vs 0.0326 +/- 0.0142, 0.0757 +/- 0.0342, 0.0483 +/- 0.0230, respectively (P < 0.01 for all). In dynamic variation of flow volume over time, RAB and SV in cirrhotic group increasingly presented flat pattern and periodically changed pattern, respectively (P < 0.01 for both). Between cirrhotic subgroups without and with EVB history, there were significant differences in flow volume, CI and N value of SV, splenic size, degree of esophageal varices (EV) and portal hypertensive gastropathy (PHG), and stepwise logistic regression revealed that N value of SV, splenic size, degree of EV and PHG were four independent factors in relation to EVB. EVB scores calculated from the regression equation had a close correlation with EVB. In patients with EVB score > 0, 88.9% of them had EVB, and in those with EVB < 0, 76.9% of them had no history of EVB.

CONCLUSION

In cirrhotics with portal hypertension, portal venous system has the features of elevated vascular resistance and hyperdynamics, and the latter mainly results from increased blood flow in SV. EVB score may become a valuable parameter in predicting occurrence of EVB.