The Role of Interventional Radiology in Treating Complications following Liver Transplantation

Utility of nifedipine use for Doppler ultrasound early after liver transplantation to predict short-term complications and long-term outcomes

PURPOSE

To evaluate the response to nifedipine administration measured by changes in hepatic arterial (HA) flow on post-operative Doppler ultrasound (US) to predict short-term complications and long-term outcomes in liver transplant (LT) patients.

METHODS

Patients who underwent LT with post-operative Doppler US within 3 days between 1 January 2005 and 31 December 2015 were included in this retrospective single center study. The patients who received and did not receive nifedipine during the Doppler US comprised the study and control groups, respectively. A positive response to nifedipine was defined as the detection of HA flow when none was present initially or a reduction in HA resistive index (RI) ≥ 0.1 after nifedipine administration. The rates of re-transplantation, re-operation, percutaneous intervention (PCI), and overall survival (OS) were recorded. Cox proportional hazards regression was used to evaluate the association of clinic-demographic variables and Doppler findings with the outcome measures.

RESULTS

444 LT patients (305 M/139F, mean age 51.7 ± 17.4 years, mean interval between LT-Doppler US 1.12 ± 0.9 days) are presented. 220 patients comprised the nifedipine study group [n = 157/220 (71.4%) responder, n = 63/220 (28.6%) nonresponder] and 224 patients comprised the control group. There was no difference in re-transplantation or PCI rates between the groups (all p-values ≥ 0.2 and ≥ 0.08, respectively). The responder group had a lower rate of re-operation vs. the control group (15.9% vs. 24.1%, p = 0.03) and nonresponder group (15.9% vs. 31.8%, p = 0.004). 1-year and 2-year OS were similar between the groups (all p-values > 0.37).

CONCLUSION

Short-term complication rates and long-term outcomes for patients with liver transplant who responded to nifedipine administration on Doppler US are similar to those who did not require nifedipine administration. A lack of response to nifedipine was associated with a higher re-operation rate.

Imaging and Intervention in the Management of Vascular Complications Following Liver Transplantation

Liver transplantation is the treatment of choice in majority of the patients with end stage liver disease. Vascular complication following liver transplantation is seen in around 7-13% of the patients and is associated with graft dysfunction and high morbidity and mortality. Early diagnosis and prompt treatment are crucial in management of these patients. Advances in interventional radiology have significantly improved the management of vascular complications using minimally invasive percutaneous approach. Endovascular management is preferred in patients with late hepatic artery thrombosis, or stenosis, whereas retransplantation, surgical revision, or endovascular management can be considered in patients with early hepatic artery thrombosis or stenosis. Hepatic artery pseudoaneurysm, arterioportal fistula, and splenic artery steal syndrome are often treated by endovascular means. Endovascular management is also preferred in patients with symptomatic portal vein stenosis, early portal vein thrombosis, and symptomatic late portal vein thrombosis, whereas surgical revision or retransplantation is preferred in patients with perioperative portal vein thrombosis occurring within 3 days of transplantation. Venoplasty with or without stent placement can be considered in patients with hepatic venous outflow tract or inferior vena cava obstruction. Transjugular intrahepatic portosystemic shunt (TIPS) may be required in transplant recipients who develop cirrhosis, often, secondary to disease recurrence, or chronic rejection. Indications for TIPS remain same in the transplant patients; however, major difference is altered vascular anatomy, for which adjunct techniques may be required to create TIPS.

Consensus report from the 7th International Forum for Liver Magnetic Resonance Imaging

Objectives

Liver-specific MRI is a fast-growing field, with technological and protocol advancements providing more robust imaging and allowing a greater depth of information per examination. This article reports the evidence for, and expert thinking on, current challenges in liver-specific MRI, as discussed at the 7th International Forum for Liver MRI, which was held in Shanghai, China, in October 2013.

Methods

Topics discussed included the role of gadoxetic acid-enhanced MRI in the differentiation of focal nodular hyperplasia from hepatocellular adenoma and small hepatocellular carcinoma (HCC) from small intrahepatic cholangiocarcinoma (in patients with chronic liver disease), the differentiation of low-grade dysplastic nodule (DN) from pre-malignant high-grade DN and early HCC, and treatment planning and assessment of treatment response for patients with HCC and colorectal liver metastasis. Optimization of the gadoxetic acid-enhanced MRI protocol to gain robust arterial and hepatobiliary phase images was also discussed.

Results and conclusions

Gadoxetic acid-enhanced MRI demonstrates added value for the detection and characterization of focal liver lesions and shows promise in a number of new indications, including regional liver functional assessment and patient monitoring after therapy; however, more data are needed in some areas, and further developments are needed to translate cutting-edge techniques into clinical practice.

Key Points

• Liver-specific MRI is a fast-growing field, with many technological and protocol advancements.

• Gadoxetic acid-enhanced MRI demonstrates value for detecting and characterizing focal liver lesions.

• Gadoxetic acid-enhanced MRI shows promise in regional functional assessment and patient monitoring.

• Further developments are needed to translate cutting-edge techniques into clinical practice.