Effects of inferior mesenteric vein flow in patients with cirrhosis.

BACKGROUND & AIMS: The inferior mesenteric vein (IMV) is detected in more than 90% of computed tomography images. Little is known about the hemodynamic features of IMV as a collateral vessel in portal hypertension, or its effects in clinical presentation and outcome. We investigated the roles of the IMV in portal hemodynamics, clinical presentation, and outcomes of patients with cirrhosis.

METHODS

We performed a prospective study of 467 patients with cirrhosis (274 men; age, 64.6 ± 10.9 y). We assessed hemodynamics in the IMV using Doppler sonography and compared these data with patients' clinical presentation and patient outcome.

RESULTS

IMV was detected in 94 patients (20.1%); 51 patients had hepatopetal flow, 33 patients had hepatofugal flow, and 10 patients had to-and-fro flow. Those with hepatofugal flow had a significantly greater number of ascites than those with hepatopetal flow, higher Child classification (P = .004), and a higher incidence of decompensated liver (51.5% vs 27.5%; P = .015) and rectal varices (56.3% vs 13.3%; P = .013). The incidence of gastroesophageal varices was lower among those with hepatofugal flow (51.5%; P = .005) or to-and-fro flow (40%; P = .008) than those with hepatopetal flow (80.4%). IMV had similar effects after adjustment for liver function. There were no differences in the cumulative rates of survival during the median 17.2 months of follow-up evaluation, when the patients with and without IMV were stratified by Child classification.

CONCLUSIONS

In patients with cirrhosis, hepatofugal flow of the IMV appears to increase the risk of ascites and liver decompensation but reduce the risk for gastroesophageal varices. Although IMV is associated with reduced liver function, it does not affect survival.