[Can the function of the transjugular intrahepatic portosystemic shunt be evaluated noninvasively by Doppler...

Transjugular intrahepatic portosystemic shunt (TIPS) is an effective treatment of complications due to portal hypertension. Possible shunt stenosis or shunt occlusion make periodical assessment of stent function necessary. Direct portal venography is the gold standard in morphologic and functional surveillance of TIPS. Controversially discussed is whether Doppler ultrasonography is effective in hemodynamical evaluation of TIPS and sufficient in prediction of shunt dysfunction. In 39 patients, 147 Doppler ultrasonographical examinations were performed and correlated with the results obtained by direct portal venography in TIPS follow-up, 43 of 47 hemodynamically relevant stenoses, including six shunt occlusions, were being diagnosed correctly by Doppler ultrasonography, by assessing maximal flow velocity in portal vein proximal to the TIPS (sensitivity 91.5%; specificity 97%). If Doppler ultrasonographical measurement of maximal flow velocity was performed within the proximal stent itself, sensitivity was only 70.4% and specificity 27%. In conclusion, assessment of portal maximal flow velocity more accurately represents hemodynamical TIPS function than Doppler ultrasonographical measurement within the proximal stent tract itself. Since, according to data presented. Doppler ultrasonography appears to be able to detect hemodynamically significant TIPS stenoses, it might reduce the number of invasive angiographies and thus contribute to more cost-effective follow-up of TIPS patients.