Splenic artery syndrome after orthotopic liver transplantation: treatment with the Amplatzer vascular plug. Cardiovasc Intervent Radiol. 2011;34:1208-1213. [PMID: 21184225 DOI: 10.1007/s00270-010-0083-9]

A systematic review of diagnostic and interventional techniques in non-occlusive hepatic artery hypoperfusion syndrome

OBJECTIVE

This systematic review aims to elucidate the diagnostic capabilities of imaging techniques in identifying Non-Occlusive Hepatic Artery Hypoperfusion Syndrome (NOHAH) and to evaluate the efficacy and outcomes of splenic artery embolization (SAE), including the choice and placement of embolic agents.

MATERIALS AND METHODS

A comprehensive literature search was conducted using PubMed, CINAHL, and Scopus databases, adhering to PRISMA guidelines. Fifteen studies encompassing 240 patients treated with embolization (using coils or Amplatzer Vascular Plugs (AVP)) were analyzed. Key metrics assessed included patient demographics, embolization techniques, embolic agents, technical success, radiologic findings pre- and post-embolization, and complication rates.

RESULTS

Among the 240 patients studied, 177 (73.8%) were reported by gender, with a majority being male (127/177, 71.7%). Doppler ultrasonography (DUS) emerged as the primary initial screening tool in 80% of studies. The hepatic arterial resistive index (RI) was a critical parameter, with mean values significantly decreasing from 0.84 pre-embolization to 0.70 post-embolization (p < 0.001). All cases confirmed technical success via digital subtraction angiography, revealing delayed hepatic arterial filling without stenosis or thrombosis. Coils were the predominant embolic agent, used in 80.8% of patients, followed by AVP in 16.3%. The overall mortality rate was 4.58%, with 29 major and 3 minor complications noted. Notably, proximal placement of coils in the splenic artery was associated with lower mortality rates compared to distal placement and showed comparable complication rates to AVPs.

CONCLUSION

DUS is a reliable screening modality for NOHAH, with post-SAE assessments showing significant improvements. The choice and location of embolization significantly impact patient outcomes, with proximal placement of coils emerging as a preferable strategy due to lower mortality rates and comparable complication profiles to alternative methods.

Surgical Versus Image-Guided Interventions in the Management of Complications After Liver Transplantation

Liver transplantation is a technically demanding surgical procedure with known complications, and the optimal approach to addressing vascular and biliary complications requires a coordinated effort between surgical and interventional radiology teams. Vascular complications involving the hepatic artery, portal vein, or hepatic veins can be characterized by their mechanism, chronicity, and timing of presentation. These factors help determine whether the optimal therapeutic approach is surgical or endovascular. Very early presentation in the perioperative period favors surgical revision, while later presentation is best addressed endovascularly. Biliary complications can be categorized as leaks or strictures, and coordinated surgical, endoscopic, and percutaneous management is needed to address these types of complications. Through advances in technique and the management of complications, outcomes after liver transplantation continue to improve.

Efficacy and Technical Feasibility of Plug-Assisted Retrograde Transvenous Obliteration of Gastric Varices via Pathways Other than the Gastrorenal Shunt

PURPOSE

To evaluate the efficacy and technical feasibility of plug-assisted retrograde transvenous obliteration of gastric varices via pathways different from the typical gastrorenal shunt.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 130 patients who underwent plug-assisted retrograde transvenous obliteration for gastric varices between 2013 and 2022. Eight patients underwent plug-assisted retrograde transvenous obliteration via different pathways. We evaluated the types of portosystemic shunts in these patients, the procedure technical and clinical success rates, and clinical outcomes.

RESULTS

In these eight patients (6 males, 2 females; mean age = 60 ± 6 years), the most common type of portosystemic shunt was a gastrocaval shunt (n = 7). Five patients had a gastrocaval shunt only; two had coexisting gastrocaval and gastrorenal shunts. One patient had a pericardiacophrenic shunt without a gastrorenal or gastrocaval shunt. The mean procedure time was 55 min. For patients with a gastrocaval shunt alone (n = 5), the mean procedure time was 40.8 min. The technical and clinical success rates were 100%. No major complication related to the procedure occurred. An initial follow-up computed tomography was performed within 2-3 weeks in all patients and revealed complete thrombosis of the gastric varices. Subsequent follow-up computed tomography (interval: 2-6 months) was performed in seven patients and showed complete disappearance of the gastric varices in all patients. During the follow-up period (range: 42 days-6.25 years), no patients experienced rebleeding or recurrence of gastric varices.

CONCLUSION

Plug-assisted retrograde transvenous obliteration via alternative portosystemic shunts is effective and technically feasible in the treatment of gastric varices.

Splenic artery steal syndrome in patients with orthotopic liver transplant: Where to embolize the splenic artery?

Purpose

This study compared proximal and distal embolization of the splenic artery (SA) in patients with splenic artery steal syndrome (SAS) after orthotopic liver transplantation (OLT) regarding post interventional changes of liver function to identify an ideal location of embolization.

Methods and materials

85 patients with SAS after OLT treated with embolization of the SA between 2007 and 2017 were retrospectively reviewed. Periinterventional DSA was used to assess treatment success and to stratify patients according to the site of embolization. Liver function was assessed using following laboratory values: bilirubin, albumin, gamma-glutamyl transferase, glutamat-pyruvat-transaminase (GPT), glutamic-oxaloacetic transaminase (GOT), Alkaline Phosphatase (ALP), aPTT, prothrombin time and thrombocyte count. Descriptive statistics were used to summarize the data. Median laboratory values of pre, 1- and 3-days, as well as 1-week and 1-month post-embolization were compared between the respective embolization sites using linear mixed model regression analysis.

Results

All procedures were technically successful and showed an improved blood flow in the hepatic artery post-embolization. Ten Patients were excluded due to re -intervention or inconsistent image documentation. Pairwise comparison using linear mixed model regression analysis showed a significant difference between proximal and distal embolization for GPT (57.0 (IQR 107.5) vs. 118.0 (IQR 254.0) U/l, p = 0.002) and GOT (48.0 (IQR 48.0) vs. 81.0 (IQR 115.0) U/l, p = 0.008) 3-days after embolization as well as median thrombocyte counts 7-days after embolization (122 (IQR 108) vs. 83 (IQR 74) in thousands, p = 0.014). For all other laboratory values, no statistically significant difference could be shown with respect to the embolization site.

Conclusion

We conclude that long-term outcomes after embolization of the SA in the scenario of SAS after OLT are irrespective of the site of embolization of the SA, whereas a proximal embolization potentially facilitates earlier normalization of liver function. Choice of technique should therefore be informed by anatomical conditions, safety considerations and preferences of the interventionalist.

Meta-analysis of Intraprocedural Comparative Effectiveness of Vascular Plugs Vs Coils in Proximal Splenic Artery Embolization and Associated Patient Radiation Exposure

PURPOSE

To compare vascular plugs to coil embolization of the proximal splenic artery and evaluate differences in radiation exposure to the patients.

METHODS

An electronic literature search was performed for relevant studies from January 2000 to July 2018 that compared the efficacy of vascular plugs vs coils in splenic artery embolization. Only studies that investigated coil or vascular plug use, without combination with other embolic agents, were included. Meta-analysis was performed using a fixed effects model approach with the inverse variance-weighted average method to determine pooled differences in time to vessel occlusion, procedure time, fluoroscopy time, total number of devices used, and radiation exposure. Heterogeneity was assessed using the I square statistic. Pooled outcomes were compared, and quality assessments were evaluated using the Newcastle Ottawa Scale.

RESULTS

Eight studies met inclusion criteria. 81 patients were embolized with vascular plugs and 52 patients with coils only. The most common indication for splenic artery embolization was trauma. Time to vessel occlusion was shorter in the vascular plug group by 7.11 minutes (P = 0.003). Fluoroscopy time was shorter by 13.82 minutes in the vascular plug cohort, and these patients received less radiation (-439 mGy) compared to the coil group (P = 0.006 and P = 0.02, respectively). The number of devices was significantly fewer in the vascular plug group (-3.54; P < 0.001). Procedure time was not statistically significant.

CONCLUSION

Our data supports the vascular plug is superior to coils for embolization of the proximal splenic artery with respect to occlusion time, fluoroscopy time, patient radiation exposure, and number occlusive devices used.

Impact of Doppler Ultrasound on Diagnosis and Therapy Control of Lienalis Steal Syndrome After Liver Transplantation

Background

Lienalis steal syndrome is a rare complication after orthotopic liver transplantation leading to severe complications. Routine duplex sonography allows early and safe detection of lienalis steal syndrome and secondarily helps to monitor the outcome by evaluating the hemodynamics.

Material/Methods

This analysis included eight patients who after orthotopic liver transplantation needed splenic artery embolization due to lienalis steal syndrome. Lienalis steal syndrome was assumed in case of elevated transaminases, bilirubinemia or persistent ascites, and the absence of further pathologies. Diagnosis was supported by ultrasound, confirmed by digital subtraction angiography, and followed by splenic artery embolization for treatment. We analyzed blood levels and ultrasound findings before and after splenic artery embolization as well as during follow-up and evaluated for incidence of severe biliary complications and survival.

Results

Arterial resistive index (RI) significantly regularized after splenic artery embolization while the maximum arterial velocity increased. The portal venous flow volume and maximum velocity decrease. Laboratory parameters normalized. Two of eight patients developed ischemic-type biliary disease. Survival rate was 88% over a median follow-up of 33 months.

Conclusions

Beside unspecific clinical findings, bedside ultrasound examination enabled a quick verification of the diagnosis and allowed direct treatment to minimize further complications. Furthermore, ultrasound can immediately monitor the therapeutic effect of splenic artery embolization.

Amplatzer vascular plug as an embolic agent in different vascular pathologies: A pictorial essay

The Amplatzer Vascular Plug (AVP) is a cylindrical plug made of self-expanding nitinol wire mesh with precise delivery control, which can be used for a variety of vascular pathologies. An AVP is an ideal vascular occlusion device particularly in high-flow vessels, where there is high risk of migration and systemic embolization with traditional occlusion devices. We performed 28 embolizations using the AVP from 2009 to 2014 and achieved complete occlusion without complications.

The Amplatzer Vascular Plug: Review of Evolution and Current Applications

The Amplatzer Vascular Plug (AVP) was created for peripheral embolization as a modification of the family of Amplatz septal occluders used in the treatment of congenital heart malformations. The device has evolved over the years and multiple versions have been launched into the market. Each of the versions of the device has some important modifications in terms of the size of the introducer's system, number of layers, and resultant thrombogenicity. It is very important for the operator to become familiar with the unique features of the AVP, and to understand the advantages and limitations of each model in the AVP family to achieve an optimal embolic result. The purpose of this article is to review the evolution and current clinical applications of the AVP in the field of interventional radiology, with emphasis on the advantages and limitations of this device in comparison with other embolization agents.

New strategies for prevention and treatment of splenic artery steal syndrome after liver transplantation

AIM: To explore a prophylactic procedure to prevent splenic artery steal syndrome (SASS), as well as a therapeutic intervention to correct it.

METHODS: Forty-three liver transplant patients were enrolled in a non-randomized controlled trial, with the eligible criterion that the diameter of the splenic artery is more than 5 mm and/or 1.5 times of the diameter of the hepatic artery. The procedure of splenic artery banding was performed in 28 of the 43 patients, with the other 15 patients studied as a control group. SASS and other complications were compared between these two groups. A new therapeutic intervention, temporary incomplete blockade of the splenic artery with a balloon, was performed to treat SASS in this study.

RESULTS: The incidence of SASS was decreased by banding the splenic artery (0/28 vs 5/15, P = 0.006), and the same result was observed in total complications associated with prophylactic procedures (2/28 vs 6/15, P = 0.014). Five patients in the control group developed SASS within 5 d after OLT, 2 of whom were treated by coil embolization of the splenic artery, whereas the other 3 by temporary blockade of the splenic artery. Reappeared or better hepatic arteries with improved systolic amplitude and increased diastolic flow were detected by Doppler ultrasonography in all the 5 patients. Local splenic ischemic necrosis and nonanastomotic biliary stricture were diagnosed respectively in one patient treated by coil embolization, and no collateral complication was detected in patients treated by temporary blockade of the splenic artery.

CONCLUSION: SASS should be avoided during the operation by banding the splenic artery. Temporary blockade of the splenic artery is a new safe and effective intervention for SASS.

Partial splenic artery embolization in cirrhotic patients

Splenomegaly is a common sequela of cirrhosis, and is frequently associated with decreased hematologic indices including thrombocytopenia and leukopenia. Partial splenic artery embolization (PSE) has been demonstrated to effectively increase hematologic indices in cirrhotic patients with splenomegaly. This is particularly valuable amongst those cirrhotic patients who are not viable candidates for splenectomy. Although PSE was originally developed decades ago, it has recently received increased attention. Presently, PSE is being utilized to address a number of clinical concerns in the setting of cirrhosis, including: decreased hematologic indices, portal hypertension and its associated sequela, and splenic artery steal syndrome. Following PSE patients demonstrate significant increases in platelets and leukocytes. Though progressive decline of hematologic indices occur following PSE, they remain improved as compared to pre-procedural values over long-term follow-up. PSE, however, is not without risk and complications of the procedure may occur. The most common complication of PSE is post-embolization syndrome, which involves a constellation of symptoms including fever, pain, and nausea/vomiting. The rate of complications has been shown to increase as the percent of total splenic volume embolized increases. The purpose of this review is to explore the current literature in regards to PSE in cirrhotic patients and to highlight their techniques, and statistically summarize their results and associated complications.

Gelfoam-assisted amplatzer vascular plug technique for rapid occlusion in proximal splenic artery embolization

OBJECTIVE

The objective of this study was to prospectively investigate the role of rapid Gelfoam-assisted occlusion of the splenic artery with an Amplatzer Vascular Plug (AVP). Ten consecutive proximal splenic artery embolizations were performed with AVP as the primary embolic agent and Gelfoam slurry as an adjunct. These cases were then compared with 10 retrospective cases of splenic artery embolization performed with AVP and augmented with coils or additional AVPs, or both, in patients with similar indications.

CONCLUSION

Successful proximal splenic artery embolization using a single Amplatzer Vascular Plug and Gelfoam slurry occurred in all cases. No recanalization was identified on imaging follow-up at an average interval of 5.1 months. Gelfoam can be used as an adjunct to AVP in proximal splenic artery embolization. Using adjunctive Gelfoam is a simple, safe, and cost-saving method of improving the occlusion efficiency of the Amplatzer Vascular Plug.

Contrast-enhanced ultrasound diagnosis of splenic artery steal syndrome after orthotopic liver transplantation

The aim of this study was to investigate the use of contrast-enhanced ultrasound (CEUS) for the detection of splenic artery steal syndrome (SASS) after orthotopic liver transplantation (OLT). Two hundred forty-seven patients underwent OLT. Blood tests and color Doppler flow imaging (CDFI) were performed at various time points after the operation. CEUS and celiac angiography were used for patients suspected of having SASS. If the diagnosis of SASS was confirmed, splenic artery embolization was performed to enhance hepatic artery flow. CEUS and angiography were performed for the assessment of postinterventional clinical outcomes. Three of the 247 patients died postoperatively, and 8 patients were suspected of having SASS because of elevated liver enzyme levels and slim or undetectable hepatic artery blood signals by CDFI at various points after the operation. In these 8 patients, CEUS showed a delayed and weak contrast-enhanced blood signal in the hepatic artery associated with a rapid and intense enhancement of the portal vein blood. No narrowing of the hyperintense signal was observed in the hepatic artery by CEUS. The 8 diagnoses of SASS were proven by celiac angiography, which showed delayed perfusion of the hepatic artery and rapid filling of the splenic artery. Immediately after the interventional procedure, CEUS demonstrated a significantly enlarged hyperintense blood signal in the hepatic artery. In conclusion, approximately 3.27% of SASS cases occur after OLT. SASS can be identified as a sluggish and weak hyperintense blood signal in the hepatic artery without the narrowing and interruption of the hypointense signal in CEUS imaging. CEUS is an effective imaging modality for the detection of SASS after OLT.