Hepatic artery thrombosis in children with liver transplants: False- positive findings at Doppler sonography and arteriography in four patients

OBJECTIVE. Patency of the hepatic artery in patients with liver transplants is evaluated with duplex Doppler sonography. In many centers, loss of an arterial waveform in the liver hilum is an indication for immediate arteriography to confirm the presence of hepatic artery thrombosis. We describe the findings in four children with liver transplants in whom occlusion of the graft artery was erroneously suggested by findings on duplex Doppler sonography and angiography. MATERIALS AND METHODS. We describe four patients 14-26 months old who had undergone liver transplant 9 days to 9 weeks earlier. The patients were critically ill with sepsis and hypotension. Duplex Doppler sonography was performed by interrogation of the hepatic artery in the liver hilum and parenchyma. When loss of an arterial waveform in the hilum was identified, angiography was performed immediately. Angiography consisted of aortography in all patients and selective celiac or superior mesenteric angiography in three patients. Autopsy was performed in all patients. RESULTS. Duplex Doppler sonography showed loss of arterial waveforms in the liver hilum in all patients; intrahepatic arterial waveforms were absent in three. The hepatic artery was not opacified at arteriography, but all patients had a patent hepatic artery at autopsy. Postmortem hepatic histology showed massive hepatic necrosis in three patients-necrosis without rejection in two and necrotizing vasculitis associated with severe rejection in one. The fourth patient had minor hepatic parenchymal injury. CONCLUSION. We conclude that failure to show flow in the hepatic artery with duplex Doppler sonography and arteriography is not necessarily indicative of arterial thrombosis. A low-flow nonocclusive phenomenon caused by massive hepatic necrosis or systemic hypotension may not be distinguishable from arterial occlusion.