Impact of contrast-enhanced ultrasound in the study of hepatic artery hypoperfusion shortly after liver transplantation: contribution to the diagnosis of artery steal syndrome.

OBJECTIVE: To assess the value of contrast-enhanced ultrasound (CEUS) in the absence of hepatic artery signal on Doppler ultrasound (DUS) in the immediate postoperative period after liver transplant.

METHODS: This prospective study included 675 consecutive liver transplants. Patients without hepatic artery signal by DUS within 8 days post-transplant were studied with CEUS. If it remained undetectable, a thrombosis was suspected. In patent hepatic artery, a DUS was performed immediately after CEUS; if low resistance flow was detected, an arteriography was indicated. Patients with high resistance waveform underwent DUS+/CEUS follow-up. Arteriography was indicated when abnormal flow persisted for more than 5 days or liver dysfunction appeared.

RESULTS: Thirty-four patients were studied with CEUS. In 11 patients CEUS correctly diagnosed hepatic artery thrombosis. In two out of 23 non-occluded arteries, a low resistance flow lead to a diagnosis of stenosis/proximal thrombosis. Twenty-one patients had absence of diastolic flow, which normalized in the follow-up in 13 patients. In the remaining eight patients, splenic artery steal syndrome (ASS) was diagnosed.

CONCLUSIONS: CEUS allows us to avoid invasive tests in the diagnostic work-up shortly after liver transplant. It identifies the hepatic artery thrombosis and points to a diagnosis of ASS.

KEY POINTS: • CEUS is useful in the diagnostic work-up shortly after liver transplant • CEUS identifies the hepatic artery thrombosis with reliability • There is little information about DUS and CEUS findings in the ASS • DUS and CEUS offer functional information useful in the diagnosis of ASS.