Endovascular management for significant iatrogenic portal vein bleeding.

Background Despite conservative treatment, hemorrhage from an intrahepatic branch of the portal vein can cause hemodynamic instability requiring urgent intervention. Purpose To retrospectively report the outcomes of hemodynamically significant portal vein bleeding after endovascular management. Material and Methods During a period of 15 years, four patients (2 men, 2 women; median age, 70.5 years) underwent angiography and embolization for iatrogenic portal vein bleeding. Causes of hemorrhage, angiographic findings, endovascular treatment, and complications were reported. Results Portal vein bleeding occurred after percutaneous liver biopsy (n = 2), percutaneous radiofrequency ablation (n = 1), and percutaneous cholecystostomy (n = 1). The median time interval between angiography and percutaneous procedure was 5 h (range, 4-240 h). Common hepatic angiograms including indirect mesenteric portograms showed active portal vein bleeding into the peritoneal cavity with (n = 1) or without (n = 2) an arterioportal (AP) fistula, and portal vein pseudoaneurysm alone with an AP fistula (n = 1). Successful transcatheter arterial embolization (n = 2) or percutaneous transhepatic portal vein embolization (n = 2) was performed. Embolic materials were n-butyl cyanoacrylate alone (n = 2) or in combination with gelatin sponge particles and coils (n = 2). There were no major treatment-related complications or patient mortality within 30 days. Conclusion Patients with symptomatic or life-threatening portal vein bleeding following liver-penetrating procedures can successfully be managed with embolization.

Removal of Caval and Right Atrial Thrombi and Masses Using the AngioVac Device: Initial Operative Experience.

PURPOSE: To describe initial single-center experience with a thrombectomy device in managing right atrial and caval thrombi, tumors, and vegetations. MATERIALS AND METHODS: A retrospective analysis of AngioVac thrombectomy performed in 16 patients (mean age 53 y ± 13; 8 men, 8 women) between August 2013 and August 2015 was performed. Indications included right atrial mass/thrombus (6/16; 37.5%) and iliocaval thrombus (10/16; 62.5%). Procedural success was defined as aspiration of > 70% volume of atrial mass/thrombus or restoration of antegrade caval flow. RESULTS: Procedural success was achieved in 4/6 (67%) right atrial masses/thrombi and 10/10 (100%) caval thrombi. All patients (8/8; 100%) with caval thrombus presenting with swelling/edema had improvement or resolution of symptoms. There were no procedural or periprocedural mortalities; complications included one major (6.3%; intraprocedural pulmonary embolus) and one minor (6.3%; access site hematoma not requiring transfusion) complication. Of 16 patients, 14 (87.5%) survived to discharge at a mean of 10 days ± 8 (range, 1-23 d), and 12 patients (75%) were alive at last known follow-up at a mean of 385 days ± 267 (range, 63-730 d). At a mean of 194 days ± 177 (range, 41-372 d), 4/16 (25%) patients were dead; no death was related to AngioVac thrombectomy. At a mean of 66 days ± 21 (range, 49-90 d) after intervention, 3/14 (21.4%) cases with procedural success had local recurrence of mass/thrombus. CONCLUSIONS: AngioVac thrombectomy can be performed with high procedural success with clinical benefit in patients with right atrial and caval masses/thrombi.

Balloon-Occluded Retrograde Transvenous Obliteration (BRTO) for Treatment of Gastric Varices: Review and Meta-Analysis.

AIM: To perform a systematic review and meta-analysis of the effectiveness and complications of BRTO for gastric varices. MATERIALS AND METHODS: A systematic review was performed to identify relevant articles. Inclusion criteria were applied to select studies with at least ten patients with acute bleeding or at-risk gastric varices treated with BRTO. Meta-analysis with random effects model was performed to calculate data for immediate technical success, clinical success, and complications. RESULTS: A total of 1,016 Patients from 24 studies met inclusion criteria. Technical success rate for BRTO was 96.4 % (95 % CI 93.7, 98.3 %; Q = 3,269.26, p < 0.01, I (2) = 99.39 %). Clinical success (defined as no recurrence or rebleed of gastric varices, or complete obliteration of varices on subsequent imaging) rate was 97.3 % (95 % CI 95.2, 98.8 %; Q = 3,105.91, p < 0.01, I (2) = 99.29 %). Major complication rate was 2.6 % (95 % CI 1.1, 4.6 %; Q = 3,348.98, p < 0.01, I (2) = 99.34 %). Esophageal variceal recurrence rate was 33.3 % (95 % CI 24.6, 42.6 %; Q = 7,291.75, p < 0.01, I (2) = 99.74 %). CONCLUSION: BRTO is safe and efficacious for gastric varices, and current best evidence suggests that BRTO could be considered as therapy for patients with gastric varices.

Endovascular management of posttraumatic and iatrogenic large pelvic pseudoaneurysms following biopsy: case report.

Pelvic traumatic and iatrogenic pseudoaneurysms supplied by the internal iliac artery are very rare but can present with pain, nerve compression, and rupture. Particularly with more chronic pseudoaneurysms, their imaging appearance can be confusing and they can be mistaken for tumors. We present two cases of pelvic pseudoaneurysms supplied by the superior gluteal artery that were initially mistaken for masses and subsequently biopsied. We report the subsequent successful endovascular embolization technique subsequently utilized for both of these cases. A high index of suspicion should be maintained to avoid biopsy of these lesions. In the appropriately selected patient, an endovascular approach may be safely used to perform embolization.

Upper extremity tumor embolization using a transradial artery approach: technical note.

Transradial access is being used with increasing frequency for interventional radiology procedures and offers several key advantages, including decreased access site complications and increased patient comfort. We report the technique of using transradial access to perform preoperative embolization of a humeral renal cell carcinoma metastasis and pathologic fracture. A transradial approach for performing humeral preoperative tumor embolization has not been previously reported, to our knowledge. In the appropriately selected patient, this approach may be safely used to perform upper extremity embolization.

Radiofrequency Ablation for the Treatment of Hepatocellular Carcinoma in Patients with Transjugular Intrahepatic Portosystemic Shunts.

PURPOSE: To assess radiofrequency (RF) ablation efficacy, as well as the patency of transjugular intrahepatic portosystemic shunts (TIPSs), in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Retrospective database review of patients with pre-existing TIPS undergoing RF ablation of HCC was conducted over a 159-month period ending in November 2013. TIPS patency pre- and post-RF ablation was assessed by ultrasound, angiography, and/or contrast-enhanced CT or MRI. Patient demographics and immediate post-RF ablation outcomes and complications were also reviewed. RESULTS: 19 patients with 21 lesions undergoing 25 RF ablation sessions were included. Child-Pugh class A, B, and C scores were seen in 1, 13, and 5 patients, respectively. Eleven patients (58 %) ultimately underwent liver transplantation. Immediate technical success was seen in all ablation sessions without residual tumor enhancement (100 %). No patients (0 %) suffered liver failure within 1 month of ablation. Pre-ablation TIPS patency was demonstrated in 22/25 sessions (88 %). Of 22 cases with patent TIPS prior to ablation, post-ablation patency was demonstrated in 22/22 (100 %) at immediate post-ablation imaging and in 21/22 (95 %) at last follow-up (1 patient was incidentally noted to have occlusion 31 months later). No immediate complications were observed. CONCLUSION: Ablation efficacy was similar to the cited literature values for patients without TIPS. Furthermore, TIPS patency was preserved in the majority of cases. Patients with both portal hypertension and HCC are not uncommonly encountered, and a pre-existing TIPS does not appear to be a definite contraindication for RF ablation.

Vascular plug-assisted retrograde transvenous obliteration of portosystemic shunts for refractory hepatic encephalopathy: a case report.

While balloon-assisted retrograde transvenous obliteration (BRTO) has been used for two decades in Asia for the management of gastric variceal bleeding, it is still an emerging therapy elsewhere. Given the shunt closure brought about by the procedure, BRTO has also been used for the management of portosystemic encephalopathy with promising results. Modified versions of BRTO have been developed, including plug-assisted retrograde transvenous obliteration (PARTO), where a vascular plug is deployed within a portosystemic shunt. To our knowledge, we present the first North American case of PARTO in the setting of a large splenorenal shunt for the management of portosystemic encephalopathy.

Renal artery stenosis in swine: feasibility of MR assessment of renal function during percutaneous transluminal angioplasty.

PURPOSE: To prospectively test--in a swine model of renal artery stenosis (RAS)--the hypothesis that magnetic resonance (MR) imaging can reveal changes in renal function at the time of percutaneous transluminal angioplasty (PTA). MATERIALS AND METHODS: In this animal care and use committee-approved study, high-grade unilateral RAS was surgically induced in six pigs. MR imaging at 3.0 T was used for intraprocedural assessment of the anatomic and physiologic changes induced by x-ray-guided PTA. With use of MR imaging, changes in single-kidney glomerular filtration rate, extraction fraction, and renal blood flow were assessed during PTA. The arterial diameter of stenosis before and after PTA was assessed by using conventional digital subtraction angiography. Mean changes in functional and anatomic parameters were compared by using the Wilcoxon signed rank test (alpha = .05). RESULTS: At digital subtraction angiography, the mean percentage of stenosis was 69% +/- 10 (standard deviation) before PTA and 26% +/- 10 after PTA (P<.03). Mean pre- and post-PTA extraction fraction values were 0.11 +/- 0.03 and 0.19 +/- 0.06, respectively (P<.03). The mean single-kidney glomerular filtration rate before PTA, 19 mL/min +/- 13, increased to 41 mL/min +/- 33 after PTA (P<.03). There was no significant change in mean renal blood flow after PTA (P=.44). CONCLUSION: In swine, MR imaging can reveal changes in renal function after x-ray-guided PTA for unilateral RAS.

MR imaging assessment of changes in renal function with renal artery stent placement in swine.

PURPOSE: To prospectively test the hypothesis that magnetic resonance (MR) imaging can detect changes in renal function at the time of renal artery stent placement in a swine model of renal artery stenosis (RAS). MATERIALS AND METHODS: In this animal care and use committee-approved study, hemodynamically significant (>50%) RAS was surgically induced in six pigs. MR imaging was employed for assessment of the anatomic and physiologic changes induced by fluoroscopically guided stent placement. With MR imaging, we assessed changes in renal blood flow (RBF), extraction fraction (EF), and single-kidney glomerular filtration rate (skGFR) during the procedure. Arterial diameter stenosis before and after stent placement was assessed with x-ray digital subtraction angiography (DSA). Mean changes in functional and anatomic parameters were compared with the Wilcoxon matched-pairs test, with an alpha level of 0.05. RESULTS: There was no significant change in mean RBF after stent deployment (P=.44). Mean EF increased from 0.19+/-0.08 before stent placement to 0.31+/-0.17 after stent placement (P=.16). Mean skGFR measurements were 25 mL/min+/-16 before stent placement and 41 mL/min+/-28 after stent placement (P<.05). According to x-ray DSA measurements, mean stenosis measurements were 60%+/-12% before stent placement and 24%+/-16% after stent placement (P<.02). CONCLUSIONS: In swine, MR imaging can detect immediate changes in renal function after radiographically guided stent placement for unilateral RAS. This functional MR technique may have applications in the setting of hybrid MR/x-ray DSA procedure suites.

Comparison of intraarterial MR angiography at 3.0 T with X-ray digital subtraction angiography for detection of renal artery stenosis in swine.

PURPOSE: To compare the accuracy of catheter-directed intraarterial (IA) magnetic resonance (MR) angiography at 3.0 T with that of x-ray digital subtraction angiography (DSA) for the measurement of renal artery stenosis (RAS) in swine. MATERIALS AND METHODS: Unilateral hemodynamically significant RAS (>50%) was induced surgically in six pigs with use of reverse cable ties. One to two weeks after surgery, each pig underwent x-ray DSA and MR angiography before and after percutaneous transluminal balloon angioplasty (PTA). X-ray DSA was performed before and after PTA of RAS by injection of iodinated contrast agent through a 5-F multiple-side hole angiographic catheter placed in the abdominal aorta under fluoroscopic guidance. MR angiography of RAS was performed before and after PTA of RAS on a 3.0-T clinical MR imager with use of gadolinium-based contrast agent. MR angiography and DSA images were analyzed with the full width at half maximum method. Percent stenosis measurements between x-ray DSA and MR angiography were compared with a paired t test and were correlated with linear regression and Bland Altman analysis (alpha = 0.05). RESULTS: Six cases of RAS were induced and imaged successfully with DSA and MR angiography techniques before and after PTA. On x-ray DSA, median stenoses was 64% (95% CI 57%-80%) before PTA and 20% (95% CI 5%-32%) after PTA. Corresponding MR angiography median stenosis measurement was 69% (95% CI 58%-80%) before PTA and 26% (95% CI 16%-36%) after PTA. A paired t test comparison did not show a difference between DSA and MR angiography (P = .16). RAS measurements on MR angiography correlated closely (P < .01) with DSA measurements (r(2) = 0.92). CONCLUSION: In swine, the accuracy of catheter-directed IA MR angiography with use of a clinical 3.0-T MR imaging unit for the measurement of RAS was similar to that of conventional x-ray DSA.