Ultrasound findings after endovascular stent deployment in transplant liver hepatic artery stenosis

Intraoperative Doppler Ultrasound for Detection of Early Postoperative Vascular Complications in Orthotopic Liver Transplants

Liver transplantation is currently the only curative treatment for patients with end-stage liver disease. However, liver transplantation can be associated with catastrophic complications in the early postoperative setting, including hepatic artery thrombosis (HAT) and portal vein thrombosis (PVT). Postoperative complications are associated with hepatic artery resistive index (RI) < 6, systolic acceleration time (SAT) > 0.08 seconds and peak systolic velocity (PSV) > 200 cm/s on doppler ultrasound (DUS). DUS is also used in an intraoperative setting to assess patency and early complications prior to the end of the operative period, allowing for early correction. This literature review evaluates the prevalence of DUS use in intraoperative settings to identify transplant complications. A lack of consistency and minimal knowledge of intraoperative DUS warrants additional research into its usage and standardization.

Doppler Characteristics of Recurrent Hepatic Artery Stenosis

OBJECTIVES

We sought to assess midterm sonographic findings in patients after stenting for hepatic artery stenosis.

METHODS

Thirty-nine hepatic artery stent procedures were performed for hepatic artery stenosis after liver transplantation between September 2009 and December 2013. Thirty cases were technically successful and met the minimum follow-up time (76 days, defined by earliest diagnosed stenosis). Routine ultrasound surveillance was obtained on all patients, and statistical analysis of the findings in the patency and restenosis groups was performed.

RESULTS

Of the 30 cases, restenosis occurred 9 times in 6 patients. Mean follow-up was 677 days. Mean time to restenosis was 267 days. Five cases (56%) were identified within the first 6 months after stent placement. Four cases (44%) were recognized in the second year after stent placement. Prior to the sonographic diagnosis of restenosis, the mean resistive indices of the main (.64 versus .57, P < .0001), left (.63 versus .54, P < .0001), right anterior (.60 versus .52, P < .0001), and right posterior (.60 versus .53, P = .001) hepatic artery branches differed among patency and restenosis groups, respectively. The mean peak systolic velocity also differed significantly between the 2 groups: 254 cm/sec in patients with eventual restenosis versus 220 cm/sec in patients without restenosis (P = .02).

CONCLUSIONS

The sonographic evaluation of hepatic artery stenosis remains critical during the first 2 years after stent placement. While the vast majority of patients do not restenose, resistive index and peak systolic velocity differed significantly between the 2 groups and may be prognostic surveillance markers for the development of restenosis.

[Arterial and portal venous complications after HPB surgical procedures: Interdisciplinary management]

The surgical treatment of hepatopancreatobiliary (HPB) diseases requires complex operative procedures. Within the last decades the morbidity (36-50 %) and mortality (<5 %) of these procedures could be reduced; nonetheless, postoperative complications still occur in 41.2 % of cases. Compared with hepatobiliary procedures, pancreatic surgery shows an increased rate of complications. Postoperative bleeding has a major effect on the outcome and the incidence is 6.7 % after pancreatic surgery and 3.2 % after hepatobiliary surgery. The major causes of early postoperative hemorrhage are related to technical difficulties in surgery whereas late onset postoperative hemorrhage is linked to anastomosis insufficiency, formation of fistulae or abscesses due to vascular arrosion or formation of pseudoaneurysms. In many cases, delayed hemorrhage is preceded by a self-limiting sentinel bleeding. The treatment is dependent on the point in time, location and severity of the hemorrhage. The majority of early postoperative hemorrhages require surgical treatment. Late onset hemorrhage in hemodynamically stable patients is preferably treated by radiological interventions. After interventional hemostatic therapy 8.2 % of patients require secondary procedures. In the case of hemodynamic instability or development of sepsis, a relaparotomy is necessary. The treatment concept includes surgical or interventional remediation of the underlying cause of the hemorrhage. Other causes of postoperative morbidity and mortality are arterial and portal venous stenosis and thrombosis. Following liver resection, thrombosis of the portal vein occurs in 8.5-9.1 % and in 11.6 % following pancreatic resection with vascular involvement. Interventional surgical procedures or conservative treatment are suitable therapeutic options depending on the time of diagnosis and clinical symptoms. The risk of morbidity and mortality after HPB surgery can be reduced only in close interdisciplinary cooperation, which is particularly true for vascular complications.