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Journal of Vascular and Interventional Radiology | 1997

Iliofemoral Deep Venous Thrombosis: Safety and Efficacy Outcome during 5 Years of Catheter-directed Thrombolytic Therapy

Haraldur Bjarnason; Janice R. Kruse; David A. Asinger; Gwen K. Nazarian; Charles A. Dietz; Michael D. Caldwell; Nigel S. Key; Alan T. Hirsch; David W. Hunter

PURPOSE To prospectively evaluate the angiographic and clinical results of using catheter-directed thrombolytic therapy for the treatment of acute iliofemoral deep venous thrombosis (IFDVT). MATERIALS AND METHODS All consecutive patients with acute IFDVT referred for thrombolytic treatment from July 1990 to December 1995 were included in this clinical data analysis. Infusions of urokinase were administered via a multisidehole infusion catheter. Angioplasty, stent placement, mechanical thrombectomy, and other procedures were often performed in conjunction with the thrombolytic procedure. RESULTS Seventy-seven patients and 87 limbs were treated. The overall technical success rate was 79%, and was 86% for iliac veins and 63% for femoral veins. The primary and secondary patency rates at 1 year were 63% and 78%, respectively, for the iliac veins, and 40% and 51%, respectively, for the femoral veins. Patients with malignant disease fared worse. Patients requiring stent placement appeared to have inferior outcomes. A previous history of DVT did not appear to affect the results. Bleeding requiring transfusion and hematomas were the major complications encountered. Pulmonary embolus was not a significant problem. Technical success rates were lower in patients who had had symptoms for more than 4 weeks compared to those who had a more recent onset of symptoms. CONCLUSION Current data suggest that catheter-directed thrombolytic therapy is safe and effective in achieving intermediate-term venous Patency. The long-term clinical benefits of this procedure remain, however, to be established.


Journal of Vascular and Interventional Radiology | 1997

Changes in Tunneled Catheter Tip Position when a Patient Is Upright

Gwen K. Nazarian; Haraldur Bjarnason; Charles A. Dietz; Casandra A. Bernadas; David W. Hunter

PURPOSE To determine the relative changes in position of tunneled catheters from supine to upright patient position and factors affecting catheter tip migration. MATERIALS AND METHODS One hundred forty-six different tunneled catheters were placed through the subclavian or jugular veins radiologically, and catheter positions were documented with use of cine radiography at the time of placement. Follow-up chest radiographs were obtained with the patient in the upright position within 48 hours after placement. Catheter tip positions were numbered from 1 to 8, with 1 representing the innominate/superior vena cava junction and 8, the lower right atrium. Patient sex and weight, the site of catheter entry, and the size and type of catheter were correlated with the relative change in position on the follow-up chest radiogrpahs. RESULTS There was a statistically significant (P < .0001) change in catheter position on the follow-up chest radiographs, with a mean difference of 1.5 catheter positions (usually mid-right atrium initially to low superior vena cava on follow-up). Catheter tip migration was greater for catheters in the subclavian veins, in females, and in obese patients. CONCLUSIONS The catheter tip migrates significantly from the initial position at the time of placement as compared to when the patient assumes the upright position. This knowledge is important in achieving the desired final catheter position.


CardioVascular and Interventional Radiology | 1996

Venous Recanalization by Metallic Stents After Failure of Balloon Angioplasty or Surgery: Four-Year Experience

Gwen K. Nazarian; William R. Austin; Scott A. Wegryn; Haraldur Bjarnason; Daniel J. Stackhouse; Wilfrido R. Castaneda-Zuniga; David W. Hunter

PurposeThis retrospective study describes our updated experience in treating venous stenoses and occlusions with metallic endovascular stents.MethodsGianturco, Palmaz, and Wallstent stents were placed in 55 patients over a 4-year period. Stent sites included the subclavian veins (9), innominate veins (3), superior vena cava (4), inferior vena cava (3), iliac veins (29), femoral veins (5), and portal veins (6). The most common indications for stent placement were malignant stenoses and chronic pelvic venous occlusions. Venoplasty and/or urokinase were used as ancillary therapy. Patients were anticoagulated for 3–6 months. Follow-up included clinical assessment and duplex ultrasound.ResultsLifetable analysis shows 59%, 63%, and 72% primary, primary assisted, and secondary 1-year patency rates, respectively. The 4-year primary patency rates were the same. Duration of patency depended on the venous site. Death was a complication of stent placement in 2 patients and 12 patients died within 6 months after stent placement from primary disease progression. Although early failures were more common in stents placed across occlusions than stenoses, 1-year secondary patency rates were comparable. Primary patency rates were only slightly lower in patients with malignant obstruction than in patients with benign disease.ConclusionEndovascular stent placement provides a nonsurgical alternative for reestablishment of venous flow and symptomatic relief in patients with benign as well as malignant venous obstruction.


Journal of Surgical Oncology | 1997

Biliary tree malignancies: The University of Minnesota experience

Chung K. Lee; Bennet R. Barrios; Haraldur Bjarnason

Because of its slow‐growing natural history, most patients with extrahepatic biliary tree malignancies present with inoperable disease. For the minority of patients with operable disease, surgical resection remains the treatment of choice and offers the patient the best chance for long‐term local control. The role of chemotherapy and radiotherapy in the management of these patients in the definitive, adjuvant, and palliative setting is expanding, although unsettled. Response rates with chemotherapy have been low and will most likely find a place in a combined multimodality setting. Radiotherapy (external beam, intraoperative, and intraluminal brachytherapy using 192Ir) has played a major role in the treatment of these cancers. The close proximity of bowel, kidney, and liver limits the external beam radiotherapy doses that can be safely delivered. Since most patients require placement of percutaneous transhepatic biliary catheters to relieve jaundice, this route has been utilized to deliver higher doses of radiation to the tumor area with intraluminal 192Ir ribbons. The University of Minnesota has treated 15 patients with extrahepatic bile duct cancers. Most were located at the bifurcation of the common bile duct and were treated with intraluminal brachytherapy alone or with external beam radiotherapy. Our results are comparable to previously reported retrospective data with a median survival of 8 months and three long‐term survivors. J. Surg. Oncol. 1997;65:298–305.


Pediatric Transplantation | 2002

Biliary stricture in living‐related donor liver transplantation: Management with balloon dilation

Sarah Jane Schwarzenberg; Harvey L. Sharp; William D. Payne; David W. Hunter; Haraldur Bjarnason; Abhinav Humar; Sally Weisdorf-Schindele; Rainer W. G. Gruessner

Abstract: Biliary stricture is a recipient graft complication, occurring late in the post‐operative period, which appears to occur with increased frequency in living‐related donor liver transplantation (LRD LTx). We reviewed the experience at the University of Minnesota in managing a biliary complication of LRD LTx. Since January 1997, 13 LRD transplants have been performed using the technique of transplantation of the left lateral segments with a small portion of segment IV. All patients had hepaticojejunostomies using a Roux‐en‐Y loop. Of the 11 surviving patients, eight had evidence of cholangitis (Gram‐negative sepsis, two patients; ascending cholangitis, three patients; or unexplained fever with elevated liver enzymes, three patients) 4–8 months after otherwise successful transplantation. Six of the patients underwent percutaneous transhepatic cholangiography (PTC) with demonstration of a stenosis at the site of the biliary anastomosis. Repeated dilation of the anastomosis led to resolution of the stenoses, normalization of liver enzymes, and prevention of further episodes of infection. No patient required revision of the hepaticojejunostomy. Computed axial tomography evidence of ductal stenosis may be subtle in this group of patients, but PTC is diagnostic. We suggest a high index of suspicion of biliary stricture in the LRD LTx population. Biliary dilation reduces the risk of life‐threatening sepsis.


CardioVascular and Interventional Radiology | 1993

Early sonographic evaluation of the transjugular intrahepatic portosystemic shunt (TIPS)

Hector Ferral; Mary C. Foshager; Haraldur Bjarnason; David E. Finlay; David W. Hunter; Wilfrido R. Castaneda-Zuniga; Janis Gissel Letourneau

The purpose of this study was to evaluate duplex and color Doppler findings in patients before and within 24 h after transjugular intrahepatic porto-systemic shunts (TIPS). Conventional duplex and color Doppler were used in the assessment of 19 patients who underwent TIPS as part of a prospective protocol. Patients were examined within 24 h before and after the procedure. Before TIPS, patency, flow direction, and peak flow velocity in the main portal vein and hepatic artery were studied, as well as patency and flow direction in hepatic veins, splenic vein, and inferior vena cava (IVC). Immediately after the procedure, sonographic identification of stent position, shunt patency, and flow dynamics were evaluated and patency and flow direction of hepatic veins, splenic vein, and IVC were determined. The portogram performed at the end of the procedure was compared with the 24-h sonographic studies after TIPS to determined sonographic/angiographic correlation. No intraparenchymal abnormalities or perihepatic fluid collections were detected after the procedure. The metallic stent was clearly seen in all patients. Mean peak shunt flow velocities were 139±50 cm/sec within 24 h after TIPS. Absence of flow through the shunt was correctly identified in one case and confirmed angiographically. Mean peak flow velocity in the portal vein before TIPS was 22±13.6 cm/sec and increased to 43.6±9.1 cm/sec after TIPS (p<0.05). The hepatic artery peak systolic velocity increased from 77±51 cm/sec before TIPS to 119±53 cm/sec after the procedure (p=0.029). Conventional duplex and color Doppler ultrasound proved to be a useful non-invasive diagnostic method to assess patients who have undergone TIPS. We propose its use as the primary diagnostic modality in these patients.


Journal of Vascular and Interventional Radiology | 1994

Chronic Iliac Artery Occlusions: Primary Recanalization with Endovascular Stents

Joseph W. Yedlicka; Hector Ferral; Haraldur Bjarnason; David W. Hunter; Wilfrido R. Castaneda-Zuniga; Kurt Amplatz

PURPOSE The authors describe treatment of chronic iliac artery occlusions with primary stent placement without prior thrombolysis or angioplasty. PATIENTS AND METHODS Eight patients with chronic iliac artery occlusions (six men and two women) underwent primary stent placement without prior use of thrombolytic agents or angioplasty. Palmaz stents were placed in seven patients and a Wallstent device was placed in one. RESULTS In all patients, revascularization was successful without residual stenoses or pressure gradients. There was no angiographic evidence of distal embolization. CONCLUSION Primary stent placement for chronic iliac artery occlusions without prior thrombolysis or angioplasty appears to be safe and efficacious and is potentially cost effective.


Journal of Vascular and Interventional Radiology | 1993

Placement of the Palmaz Stent with Use of an 8-F Introducer Sheath and Olbert Balloons

Haraldur Bjarnason; David W. Hunter; Hector Ferral; Martin R. Crain; Steven E. Miltz-Miller; Scott A. Wegryn; Wilfrido R. Castaneda-Zuniga; Kurt Amplatz

PURPOSE The authors describe a modified technique for delivering Palmaz 30-mm stents. MATERIALS AND METHODS The modification is based on the use of an 8-mm Olbert balloon mounted on a 5.8-F shaft. The Palmaz stent is crimped onto the balloon by using finger pressure only. An 8-F introducer sheath can be used instead of a 10-F sheath. The surface material of the balloon prevents the stent from moving as it is introduced through the sheath and lesion. The balloon has a very small profile after deflation, which means it can be easily removed without dislodging the stent. The balloon can be used for placement of more than one stent. RESULTS Nineteen Palmaz 30-mm stents have been placed with this method, and there have been no complications or difficulties related to this method. In one case, four stents were delivered by using the same balloon. CONCLUSION This modification should reduce the complications of stent delivery, especially in small iliofemoral systems.


Academic Radiology | 1999

Tracheobronchial metal stents: Effects of covering a bronchial ostium in pigs

Haraldur Bjarnason; Barbara C. Cahill; Nils-Einar Kløw; Young-Min Han; Myra Urness; Roland Gunther; Maria R. Gomes; Michael S. Rosenberg; Charles A. Dietz; David W. Hunter

RATIONALE AND OBJECTIVES The purpose of this study was to examine the effects of placing a metal stent across a bronchial orifice. MATERIALS AND METHODS Nine pigs were used as test subjects, because the right upper lobe bronchus comes directly off the trachea in these animals. One of three types of metal stents was placed into the trachea of each pig and covered the orifice of the right upper lobe bronchus. Follow-up studies were performed at 1 and 3 months to evaluate the right upper lobe for signs of bronchial obstruction, infection, and atelectasis. The animals were sacrificed at 3 months to study the histopathologic changes of the trachea and lungs. RESULTS Two upper lobe bronchi remained patent; seven were obstructed by granulation tissue or plugs of mucus and inflammatory cells. Right upper lobe infiltration and atelectasis were seen in eight animals. Interestingly, radiographic opacities were also common in other lung segments. There was a tendency toward fewer and less extensive lung opacities at 3 months compared with that at 1 month. At histopathologic examination, areas of both acute and chronic pneumonia were found in the right upper lobe of all animals. The segment of trachea covered by the stent was lined with a thin layer of granulation tissue containing neutrophils, monocytes, and lymphocytes. The stent luminal surface was covered with columnar, cuboidal, and stratified squamous epithelium. Tracheal stenosis was seen in three animals because of excessive granulation tissue in two and a collapsed stent in one. CONCLUSION Placement of metal stents in pig trachea covering the orifice of the right upper lobe bronchus resulted in retention of secretions and secondary infection in the right upper lobe and other distant lung segments.


Radiology | 1993

Refractory ascites: early experience in treatment with transjugular intrahepatic portosystemic shunt.

Hector Ferral; Haraldur Bjarnason; Scott A. Wegryn; Gail J. Rengel; Gwen K. Nazarian; Jeffrey M. Rank; S. Murthy Tadavarthy; David W. Hunter; Wilfrido R. Castaneda-Zuniga

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Hector Ferral

LSU Health Sciences Center New Orleans

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Kurt Amplatz

University of Minnesota

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