Portal vein arterialization for hepatic artery thrombosis in liver transplantation: a case report, Doppler-ultrasound aspects, and review of the literature.

Portal vein arterialization (PVA) is a salvage procedure for insufficient hepatic arterial or portal vascularization. It plays a role in auxiliary and orthotopic liver transplantation (OLT). In OLT, current indications for PVA include hepatic artery thrombosis (HAT), pre-OLT or post-OLT extended splanchnic vein thrombosis, intraoperative low portal flow, and anatomic variations like the absence of portal and mesenteric veins. Out of the transplantation domain, PVA is used both in extensive surgery for malignancies of the liver, biliary tract, and pancreas and in the treatment of fulminant hepatic failure (FHF) due to intoxications. We describe a case of acute post-OLT HAT successfully treated with PVA as a short bridge to retransplantation. By Doppler ultrasound of clinical PVA we detected an increased intrahepatic portal flow velocity, with disappearance of the arterial spikes, a finding that needs further investigation. PVA represents a rare surgical procedure. In fact, it has been used most of all in urgent conditions or in case of abrupt vascular complications during surgery. According to the literature, PVA emerges as a salvage procedure for poor arterial or portal hepatic flow, both in OLT and in general abdominal surgery. The outcome of this procedure is unpredictable. The aim of the shunt is to gain time, awaiting the onset of collateral arterial vessels or the performance of definitive surgery. Its early thrombosis may be a catastrophic event, due to acute liver ischemia. In contrast, a late occlusion is often well tolerated. Strict surveillance is always useful because sometimes it is mandatory to embolize the arterioportal fistula to treat or to prevent the onset of portal hypertension.