38th National Congress of the Italian Transplantation SocietyLiver transplantationDiagnosis and Management of Hepatic Artery Complications After Liver Transplantation

- Because the hepatic artery is the only route by which oxygenated blood is supplied to the transplanted liver, obstruction of the hepatic artery results in parenchymal and biliary ischemia.
- Early diagnosis and prompt treatment of vascular complications result in longer graft and patient survival.
- The presence of tardus-parvus waveforms significantly improved the diagnostic accuracy of Doppler sonography in our series (100% positive predictive value), and the detection of such waveforms should thus prompt emergency angiography.

BackgroundWe assessed the usefulness of color Doppler imaging in diagnosis and monitoring hepatic artery complications after liver transplantation.MethodsSubjects were 421 liver transplant recipients who underwent serial ultrasound (US) color Doppler evaluations of the hepatic arteries after surgery.ResultsWe saw 4 hepatic arterial complications after liver transplantation (13 thrombosis, 29 stenosis, 2 kinking, 2 pseudo-aneurysm, and 2 pseudo-aneurysm rupture). All subjects underwent US color Doppler examination periodically after surgery. In 6 cases of early thrombosis, hepatic arterial obstruction was diagnosed with absence of Doppler signals; in the other 7 cases (late hepatic artery thrombosis), thrombosis was suspected for the presence of intra-parenchymal “tardus-parvus” waveforms. In all of the cases, computed tomography angiography showed obstruction of the main arterial trunk and the development of compensatory collateral circles (late hepatic artery thrombosis). In 10 of the 29 cases of stenosis, Doppler ultrasonography examination revealed stenotic tract and intra-hepatic tardus-parvus waveforms; in 17 stenosis cases, the site of stenosis could not be identified, but intra-parenchymal tardus-parvus waveforms were recorded. In 2 patients, hepatic artery stenosis occurred with ischemic complications.ConclusionsThe use of US color Doppler examination allows the early diagnosis of hepatic arterial complications after liver transplantation. Tardus-parvus waveforms indicated severe impairment of hepatic arterial perfusion from either thrombosis or severe stenosis. The presence of these indirect signs enhanced the accuracy of color Doppler diagnosis, and detection should prompt therapy.