Jan Raupach

Wedged hepatic venography for targeting the portal vein during TIPS: comparison of carbon dioxide and iodinated contrast agents.

Purpose: Carbon dioxide (CO2) can traverse the hepatic sinusoids better than iodinated contrast medium and has been used by many interventionalists for wedged hepatic venography during transjugular intrahepatic portosystemic shunt (TIPS) procedures. Our study was designed to compare the extent of the portal vein opacification using either CO2 or iodinated contrast medium. Methods: Wedged hepatic venography for portal vein opacification during TIPS was performed using hand injection through a 6.5 Fr diagnostic catheter. Portograms of 36 patients performed with 10 ml of iodinated contrast medium were retrospectively compared with portograms of 45 patients performed with 30-40 ml of CO2. Opacification of the right portal vein branch including the portal vein bifurcation was defined as a successful study. Results: Using CO2 the right portal vein branch and the portal vein bifurcation were opacified in 87% of patients (39 of 45); only a part of the right portal vein branch was opacified in 6% of patients and no opacification of any portal vein branch was seen in 7% of patients. Using iodinated contrast medium, there was opacification of the portal vein bifurcation in 25% of patients (9 of 36), of a part of the portal vein branch in 36% and no opacification of any branch in 39%. There was one case of hepatic laceration from CO2 wedged venography which was treated with microcoil embolization. Conclusions: Using CO2 as a contrast medium, opacification of the portal vein bifurcation by wedged hepatic venography was seen in 87% of patients, in comparison with only 25% when iodinated contrast medium was used (p < 0.001). CO2 is superior to iodinated contrast medium for wedged hepatic venography during TIPS.

Influence of the Secondary Deployment of Expanded Polytetrafluoroethylene–covered Stent Grafts on Maintenance of Transjugular Intrahepatic Portosystemic Shunt Patency

PURPOSE To evaluate the effects of secondary deployment of expanded polytetrafluoroethylene (ePTFE)-covered stent grafts in the treatment of dysfunctional transjugular intrahepatic portosystemic shunts (TIPSs) in comparison with other common approaches (conventional angioplasty or implantation of bare metal stents). MATERIALS AND METHODS A retrospective review of 121 dysfunctional bare metal TIPS presenting between 2000 and 2004 was conducted. The group was divided into four subgroups according to the type of intervention: conventional angioplasty (52 cases; 43%), bare metal stent deployment (35 cases; 28.9%), nondedicated ePTFE-covered stent-graft deployment (15 cases; 12.4%), and dedicated ePTFE-covered stent-graft deployment (19 cases; 15.7%). In all four groups, the primary patency after the specific intervention was calculated and mutually compared. RESULTS Primary patency rates after 12 and 24 months were 49.7% and 25.3%, respectively, in conventional angioplasty; 74.9% and 64.9%, respectively, with bare metal stents; 75.2% and 64.5%, respectively, with nondedicated ePTFE-covered stent grafts; and 88.1% and 80.8%, respectively, with dedicated ePTFE-covered stent grafts. CONCLUSIONS In the treatment of dysfunctional TIPS, better patency after the intervention was obtained by deploying dedicated ePTFE-covered stent grafts in comparison with conventional angioplasty, bare metal stents, and nondedicated ePTFE-covered stents.

Endovascular Treatment of Acute and Chronic Thoracic Aortic Injury

Our aim is to present midterm results after endovascular repair of acute and chronic blunt aortic injury. Between December 1999 and December 2005, 13 patients were endovascularly treated for blunt aortic injury. Ten patients, 8 men and 2 women, mean age 38.7 years, were treated for acute traumatic injury in the isthmus region of thoracic aorta. Stent-graftings were performed between the fifth hour and the sixth day after injury. Three patients (all males; mean age, 66 years; range, 59–71 years) were treated due to the presence of symptoms of chronic posttraumatic pseudoaneurysm of the thoracic aorta (mean time after injury, 29.4 years, range, 28–32). Fifteen stent-grafts were implanted in 13 patients. In the group with acute aortic injury one patient died due to failure of endovascular technique. Lower leg paraparesis appeared in one patient; the other eight patients were regularly followed up (1–72 months; mean, 35.6 months), without complications. In the group with posttraumatic pseudoaneurysms all three patients are alive. One patient suffered postoperatively from upper arm claudication, which was treated by carotidosubclavian bypass. We conclude that the endoluminal technique can be used successfully in the acute repair of aortic trauma and its consequences. Midterm results are satisfactory, with a low incidence of neurologic complications.

COMPARISON OF DUPLEX ULTRASONOGRAPHY AND MAGNETIC RESONANCE IMAGING IN THE DETECTION OF SIGNIFICANT RENAL ARTERY STENOSIS

OBJECTIVE The aim of our study was to evaluate duplex ultrasonography (DUS) and magnetic resonance angiography (MRA) in detection of haemodynamically significant renal artery stenosis (RAS). METHODS The study included patients with high clinical suspicion of renovascular hypertension (RVH). The imaging of renal arteries was performed by DUS, MRA and digital subtraction angiography (DSA). Significant RAS was defined as maximum systolic velocity > or =180 cm/sec (DUS) or as 60% reduction of the endoluminal arterial diameter (MRA, DSA). The results of DUS and MRA were assessed in respect to the results of DSA. RESULTS Arterial supply of 186 kidneys in 94 patients was evaluated. DSA revealed significant RAS in 61 kidneys evaluated. DUS was not able to examine arterial supply in 18 kidneys of 13 patients. In the detection of significant RAS, DUS was characterized by sensitivity and specificity of 85% and 84%. MRA achieved satisfactory imaging quality in all but one kidney evaluated. The sensitivity and specificity of MRA in the detection of significant RAS was 93% and 93%, respectively. CONCLUSION In patients with high clinical probability of RVH, MRA proved to be more reliable and superior in both sensitivity and specificity to DUS in the detection of significant RAS.

Autologous vein stent-graft: feasibility study.

PURPOSE To evaluate expandable stents healed into vein wall as autologous vein stent-grafts for endoluminal grafting. MATERIALS AND METHODS Balloon expandable stents were placed into external jugular veins of eight dogs. Stent and vein patency was followed by ultrasonography. Five weeks after stent placement, jugular veins with endothelialized stent were harvested. The autologous vein stent-grafts were divided into two groups. In group A, autologous vein stent-grafts (n = 3) were placed immediately into Baker solution for microscopic examination. In group B, autologous vein stent-grafts (n = 3) underwent mechanical manipulation; they were compressed, mounted on angioplasty balloon, pushed through a 9-F sheath and dilated. The autologous vein stent-graft endothelialization and changes after mechanical manipulation were evaluated by light and electron microscopy. RESULTS Stent placement was successful in seven dogs. One stent migrated into the pulmonary artery. One well placed stent was damaged by compression dressing and thrombosed. At 5 weeks, gross and microscopic examinations revealed the autologous vein stent-grafts were fully covered by a 0.115- +/- 0.036-mm-thick neointimal layer. Small wall thrombus was observed in one autologous vein stent-graft. Repeated manipulations did not result in any intimal damage or stent loosening in the autologous vein stent-grafts. CONCLUSION Expandable stents healed into a vein have potential to be used as autologous vein stent-grafts for endoluminal grafting without risk of disruption during percutaneous transcatheter introduction.

Fatal Intraventricular Hemorrhage After the Extracranial Carotid Artery Angioplasty and Stent Placement

We report on a 72-year-old female with an unusual intracranial bleeding complication after an extracranial carotid artery stenting procedure performed for a tight left ICA stenosis associated with contralateral carotid occlusion. Two hours after the procedure, the initial signs of intracranial bleeding appeared that led to the patient’s demise 5 days later. A brain CT showed and autopsy proved massive intraventricular bleeding. To our knowledge, our case is only the second report of isolated reperfusion intraventricular hemorrhage post-CAS.

Endovascular brachytherapy of transjugular intrahepatic portosystemic shunt

Purpose: To evaluate the technical feasibility and efficacy of endovascular brachytherapy with Iridium-192 in the prevention of restenosis caused by neointimal hyperplasia of transjugular intrahepatic portosystemic shunt (TIPS).Materials and Methods: The endovascular brachytherapy with high dose rate automatic afterloading system was performed in six patients with recurrent of stenosis of TIPS. We used a single dose fraction of 12 Gy delivered at 3 millimeter (mm) from the source axis to the stenotic vessel segment in five patients with spiral Z-stent, and 15 Gy at 5 mm in one patient with Wallstent.Results: Follow-up time ranged from 148 to 639 days. In one patient, restenosis occurred in the treated vessel segment, diagnosed 71 days after endovascular brachytherapy by doppler ultrasound. All other patients were, during the follow-up time, without restenosis in the irradiated vessel segment. Radiation-associated side effects were not observed.Conclusions: Endovascular brachytherapy of TIPS is technically feasible and may be done as a part of the percutaneous revision of the shunt. This pilot study may be the largest experience of treating TIPS restenosis in humans to date. For definitive conclusions, a lot of studies are needed.

Laparoscopic Left Renal Vein Transposition for Nutcracker Syndrome.

The left renal vein (LRV) reimplantation into the distal inferior vena cava is considered to be the gold standard of care for symptomatic nutcracker syndrome (NCS). The vast majority of these surgical procedures are performed by open surgery. Experiences with minimally invasive laparoscopic surgery in this field are very limited. We present a case of a 17-year-old boy with NCS in whom the transposition of the LRV was done laparoscopically. The patient suffered from left flank pain, painful left-sided varicocele, microscopic hematuria, proteinuria, and oligoasthenospermia. There were no intraoperative complications, and the postoperative course was uneventful. At 12-month follow-up, hematuria, left flank pain, and left testicular pain resolved. Duplex ultrasonography revealed patent LRV. Laparoscopic LRV transposition appears to be safe, feasible, and has favorable postoperative course.

Emergent Carotid Thromboendarterectomy for Acute Symptomatic Occlusion of the Extracranial Internal Carotid Artery

Background: Strokes secondary to acute internal carotid artery (ICA) occlusion are associated with an extremely poor prognosis. The best treatment approach in this setting is still unknown. The aim of our study was to evaluate the efficacy, safety, and outcomes of emergent surgical revascularization of acute extracranial ICA occlusion in patients with minor to severe ischemic stroke. Methods: A retrospective analysis was performed using prospectively collected data of consecutive patients who underwent carotid thromboendarterectomy for symptomatic acute ICA occlusion during the period from January 2013 to December 2015. Primary outcomes were disability at 90 days assessed by the modified Rankin Scale (mRS) and neurological deficit at discharge assessed using the National Institute of Health Stroke Scale (NIHSS). Secondary outcomes were the recanalization rate, 30-day overall mortality, and any intracerebral bleeding. Results: During the study period, a total of 6 patients (5 men and 1 woman) with a median age of 64 years (range: 58-84 years) underwent emergent reconstruction for acute symptomatic ICA occlusion within a median of 5.4 hours (range: 2.9-12.0 hours) after symptoms onset. The median presenting NIHSS score was 10.5 points (range: 4-21). Before surgery, 4 patients (66.7%) had been treated by systemic recombinant tissue plasminogen activator lysis. The median time interval between initiation of intravenous thrombolysis and carotid thromboendarterectomy was 117.5 minutes (range: 65-140 minutes). Patency of the ICA was achieved in all patients. On discharge, the median NIHSS score was 2 points (range: 0-11 points). There was no postoperative intracerebral hemorrhage and zero 30-day mortality rate. At 3 months, 5 patients (83.3%) had a good clinical outcome (mRS ≤ 2). Conclusion: Patients presenting with minor to severe ischemic stroke syndromes due to isolated extracranial ICA occlusion may benefit from emergent carotid revascularization. Thorough preoperative neuroimaging is essential to aid in selecting eligible candidates for acute surgical intervention.

Stent-grafts in TIPS

The transjugular intrahepatic portosystemic shunt (TIPS) is a percutaneous, minimally invasive method of reducing an increased portal pressure in patients with symptomatic portal hypertension. TIPS is done under local anesthesia on awake, mildly sedated patients and can be performed in emergency settings, in patients at both extremes of age, and in those with poor liver function and massive ascites who often are not considered candidates for shunt surgery. In the past decade, TIPS has been shown to be effective in variceal bleeding, refractory ascites, portal gastropathy, hepatic hydrothorax, and the Budd-Chiari syndrome [1]. During a TIPS procedure an intrahepatic shunt is performed by using an expandable stent to connect a large hepatic vein with a main branch of the portal vein. The major disadvantage of TIPS is the high rate of stenoses or occlusions necessitating careful follow-up of these patients and repeated interventional corrections of insufficient shunts. Depending on the definition of the shunt stenosis and surveillance protocols, stenoses of greater than 50% have been reported in 25% to 50% of cases within 6 to 12 months of shunt creation [2–5]. However, these patients were rarely symptomatic, and recurrent variceal bleeding was seen in fewer than 25% of patients with significant TIPS stenosis [6, 7]. The high rate of shunt stenoses is the major reason for the relatively poor cost effectiveness of TIPS when compared with endoscopic or surgical treatment. Significant research has been carried out to improve primary shunt patency. In a series of animal and human studies, several investigators have reported a significant reduction in the development of TIPS stenoses with the use of covered stents, i.e., stent-grafts. The graft material can provide a barrier between the flowing blood and the traumatized liver parenchyma. In addition to improving primary and secondary patency of TIPS, stent-grafts play an important role in sealing off an extrahepatic portal vein leak during TIPS [8]. Worsened encephalopathy after TIPS can be treated more easily by using a special design of constrained stent-graft creating shunt stenosis than by previously described shunt reduction methods [9]. The use of stent-grafts that traverse malignant hepatic tumor in TIPS potentially can prevent tumor invasion into the shunt and reduce the possibility of vascular spread and seeding of tumor in the lungs [10, 11]. The purpose of this paper is to analyze the causes of TIPS stenoses and occlusion and summarize the current results of experimental and clinical uses of stent-grafts. The role of stent-graft implantation in sealing an extrahepatic portal vein leak, a rare but potentially fatal complication of TIPS procedure, also is discussed.