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1.
Clinical Experience with Covered Wallstents for Biliary Malignancies: 23-Month Follow-Up 总被引:4,自引:4,他引:0
Plinio Rossi Mario Bezzi Filippo M. Salvatori Claudio Panzetti Michele Rossi Gianluca Pavia 《Cardiovascular and interventional radiology》1997,20(6):441-447
Purpose: To evaluate the effectiveness of partially covered metallic Wallstents to prevent tumoral ingrowth in patients with neoplastic
obstruction of the biliary tract.
Methods: Twenty-one patients with malignant obstructive jaundice have been treated with Wallstents partially covered with a polyurethane
polymer. In total, 36 covered stents (8 and 10 mm in diameter, 70 and 90 mm long) were deployed. All the stents were free
from covering at both ends.
Results: Jaundice was successfully treated in 100% of cases. There were no problems related to the releasing system during stent positioning,
no major complications, and no incompatibility reactions to the materials composing the endoprostheses. At 23-month follow-up,
6 patients are still alive and 15 are dead; of these 15 patients, 11 died in the first 6 months and the last 4 died between
6 and 23 months. Seven patients had an obstructed stent; in four of these, cholangioscopy showed the presence of tumoral ingrowth
and in one it showed necrotic tissue with biliary pigments and inflammatory cells. No biopsy specimen was obtained in the
remaining two patients with stent obstruction. The follow-up, ranging from 7 to 23 months, showed a primary patency of 46.8%
and 24.6% and an assisted patency of 66.3% and 59% at 6 months and 23 months, respectively.
Conclusions: Covered metallic stents are effective and may produce improved survival in patients with malignant biliary obstruction (27.8%
at 23 months). Stent patency, however, is similar to that of uncovered stents. Modifications in the design of the covering
membrane may reduce stent obstruction resulting from disruption of the plastic covering.
Received: 0/00/00/Accepted: 0/00/00 相似文献
2.
Polyorethaoe-covered nitinol strecker stents as primary palliative treatment of malignant biliary obstruction 总被引:5,自引:3,他引:2
Kanasaki S Furukawa A Kane T Murata K 《Cardiovascular and interventional radiology》2000,23(2):114-120
Purpose: To evaluate the clinical efficacy of the polyurethane-covered Nitinol Strecker stent in the treatment of patients with malignant
biliary obstruction.
Methods: Twenty-three covered stents produced by us were placed in 18 patients with malignant biliary obstruction. Jaundice was caused
by cholangiocarcinoma (n = 5), pancreatic cancer (n = 6), gallbladder cancer (n = 4), metastatic lymph nodes (n = 2), and tumor of the papilla (n = 1).
Results: The mean patency period of the stents was 37.5 weeks (5–106 weeks). Recurrent obstructive jaundice occurred in two patients
(11%). Adequate biliary drainage over 50 weeks or until death was achieved in 17 of 18 patients (94.4%). Late cholangitis
was observed in two patients whose stents bridged the ampulla of Vater. Other late severe complications were not encountered.
Conclusion: Although more study is necessary, our results suggest the clinical efficacy of our covered Nitinol Strecker stent in the
management of obstructive jaundice caused by malignant diseases. 相似文献
3.
Venous recanalization by metallic stents after failure of balloon angioplasty or surgery: Four-year experience 总被引:2,自引:0,他引:2
Gwen K. Nazarian M.D. William R. Austin Scott A. Wegryn Haraldur Bjarnason Daniel J. Stackhouse Wilfrido R. Castañeda-Zúñiga David W. Hunter 《Cardiovascular and interventional radiology》1996,19(4):227-233
Purpose: This retrospective study describes our updated experience in treating venous stenoses and occlusions with metallic endovascular
stents.
Methods: Gianturco, 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.
Results: Lifetable 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.
Conclusion: Endovascular stent placement provides a nonsurgical alternative for reestablishment of venous flow and symptomatic relief
in patients with benign as well as malignant venous obstruction.
Received: 0/00/00/Accepted: 0/00/00 相似文献
4.
Lee JM Han YM Lee SY Kim CS Yang DH Lee SO 《Cardiovascular and interventional radiology》2001,24(1):25-30
Purpose: To evaluate the efficacy of the placement of covered metallic stents for palliation of gastrointestinal anastomotic strictures
secondary to recurrent gastric cancer.
Methods: Under fluoroscopic guidance, placement of one or two self-expandable covered metallic stents was attempted perorally in 11
patents (aged 48–76 years) with anastomotic stenoses due to recurrent gastric malignancies. The strictures involved both the
afferent and efferent loops in three patients. All patients had poor peroral food intake with severe nausea and vomiting after
ingestion. The technical and clinical success was evaluated.
Results: Placement of the covered stent was technically successful in 13 of 15 (87%) attempts in ten patients. After the procedure,
9 of 11 (82%) patients overall were able to ingest at least a liquid diet and had markedly decreased incidence of vomiting.
During the follow-up of 2–31 weeks (mean 8.5 weeks) there were no major complications.
Conclusion: These preliminary results suggest that flexible, covered stents may provide effective palliation of malignant anastomotic
stricture secondary to recurrent gastric cancer. 相似文献
5.
Jens J. Froelich Martin Hoppe Christina Freymann Thomas Thiel Hans-Joachim Wagner Klemens H. Barth Klaus J. Klose 《Cardiovascular and interventional radiology》1997,20(5):369-376
Purpose: Catheters are compared in vitro to evaluate the efficacy of thrombolysis during urokinase infusion within the thrombus.
Methods: Six catheters were introduced individually into human thrombus within a stenotic flow model. Urokinase was infused continuously
into the thrombus. To quantify the efficacy of thrombolysis, pressure gradients were recorded proximal and distal to the thrombus
and during the course of infusion. Uniformity of lysis was assessed radiographically.
Results: The fastest and most homogeneous thrombolysis was achieved with the EDM and the straight-flush catheter, shown by decreasing
transthrombotic pressure gradients. All other catheter designs showed less homogeneous and delayed thrombolysis (p≤ 0.001, Friedmann-Test, Schaich-Hamerle). There was no significant difference in the efficacy of thrombus dissolution between
the EDM and the straight-flush catheter (Wilcoxon, matched pairs, p> 0.7).
Conclusion: The EDM catheter and the straight flush catheter achieved the most homogeneous and fastest thrombolysis, apparently due to
the best urokinase distribution within the thrombus.
Received: 0/00/00/Accepted: 0/00/00 相似文献
6.
Dierk Vorwerk Rolf W. Guenther Karl Schürmann 《Cardiovascular and interventional radiology》1997,20(5):359-363
Purpose: To report on the efficacy of fixing fresh venous thrombus to the venous wall by stent placement.
Methods: Seven patients underwent stenting to treat acute venous thrombosis. In two patients, the hemodialysis fistula was thrombosed
with the thrombus extending into the brachial veins. In three patients, the hemodialysis fistula was patent but massive swelling
of the ipsilateral arm was caused by proximal venous thrombosis. Two patients presented with iliac venous thrombosis within
stented pelvic veins. Stent placement was preceded by other mechanical thrombectomy methods in all cases.
Results: Attachment of thrombus to the venous wall was successful in all cases treated. Acute rethrombosis did not occur. Follow-up
patency in dialysis patients was 7.2 ± 2.1 months. One patient had rethrombosis of the dialysis graft 3 months after primary
treatment. Three patients developed restenosis within a mean period of 7.7 months. One shunt remained patent for 10 months
with no event of reobstruction during follow-up. In both patients with iliac stent placement, the vein remained patent over
a follow-up period of 8 and 12 months respectively.
Conclusion: Stenting fresh venous thrombus can achieve immediate venous patency. It may be used as an alternative approach when all other
percutaneous methods fail. Frequent restenosis within stented veins limits its use to very selected cases.
Received: 0/00/00/Accepted: 0/00/00 相似文献
7.
Transjugular intrahepatic portosystemic shunt (TIPS) is a well-validated decompressive therapy option to manage ascites and variceal bleeding secondary to portal hypertension. Complications following TIPS procedures include hepatic encephalopathy, liver failure, and TIPS dysfunction. TIPS dysfunction is due to occlusion or stenosis of the TIPS shunt and can be caused by acute or chronic thrombosis. TIPS thrombosis is often treated with mechanical thrombectomy or catheter-directed thrombolytic therapy. Most cases of in-stent occlusion can be treated via a transjugular approach with recanalization or placement of additional stents. We present a case of a 72-year-old female who presented with worsening ascites 17 months after initial TIPS procedure; she was found to have a large thrombus completely occluding the TIPS stent. In our case, a combined transhepatic and transjugular approach was required for TIPS revision given the extent of well-organized clot located near the hepatic venous end of the stent, resulting from prolonged stent occlusion. This was an extremely challenging scenario with two overlapping covered stents and a bare metal stent at the hepatic venous end in the setting of chronic thrombosis and a well-organized fibrous cap. The case highlights the need for optimal initial placement of the primary TIPS shunt to avoid the need for subsequent complex interventions to maintain TIPS shunt patency. 相似文献
8.
Gary P. Siskin Brian F. Stainken Valerie S. Mandell R. Clement Darling Kyran Dowling Allen Herr 《Cardiovascular and interventional radiology》1999,22(5):375-380
Purpose: To evaluate the role of metallic stents in treating stenoses involving prosthetic arterial bypass grafts.
Methods: Patients undergoing stent placement within a failing prosthetic bypass graft, during a 41-month period, were reviewed for
treatment outcome and complications. The indications for stent placement in 15 patients included severe claudication (n= 3), rest pain (n= 9), and minor or major tissue loss (n= 3). Lesions were at the proximal anastomosis (n= 6), the distal anastomosis (n= 3), or within the graft (n= 6).
Results: Treatment with metallic stents was successful in all patients. There was one acute stent thrombosis, successfully treated
with thrombolytic therapy. Follow-up data are available for a mean duration of 12.3 months. The mean duration of primary patency
was 9.4 months with 6- and 12-month primary patency rates of 51.9% and 37.0%, respectively. The mean duration of secondary
patency was 12.1 months with 6- and 12-month secondary patency rates of 80.0% and 72.7%, respectively. Two patients with discontinuous
runoff and preexisting gangrene required a below-knee amputation. Six patients were revised surgically after stent placement
(at a mean of 10.8 months). Three late deaths occurred during follow-up.
Conclusion: Given the mortality risks of surgical revision and the reduced life expectancy of this patient population, metallic stent
placement represents a viable, short-term treatment option for stenoses within or at the anastomoses of prosthetic grafts.
Further evaluation is warranted to compare intragraft stent placement with surgical graft revision. 相似文献
9.
Roy S Laerum F Brosstad F Kvernebo K Sakariassen KS 《Cardiovascular and interventional radiology》2000,23(2):131-137
Purpose: Lysis of a thrombus is a function of the local concentration of thrombolytic enzymes. This study was designed to determine
in a porcine model of acute deep vein thrombosis (DVT) whether perithrombic sequestration of small volumes of a concentrated
enzyme solution can accelerate the process of thrombolysis.
Methods: DVT was induced in both hind limbs using a previously described technique (n = 32). Thirty minutes later the animal was heparinized and unilateral thrombolysis was attempted using 8 mg recombinant tissue plasminogen
activator (rt-PA); saline was administered in the opposite leg. For conventional high-volume infusion (CI) (n = 5) rt-PA (0.067 mg/ml) was infused at 1 ml/min. For sequestrated thrombolysis the external iliac vein was endoluminally occluded,
and rt-PA (0.25 mg/ml) administered either for proximal injection (ST-P) (n = 5), as a bolus every 3 min through a microcatheter placed via the balloon catheter, or for transthrombic injection (ST-T) (n = 5), as a bolus every 3 min through a Katzen wire in the balloon catheter. At autopsy, the thrombus mass in the iliofemoral veins
was measured, and the extent of residual thrombosis in the venous tributaries graded at four sites. From these data a thrombolysis
score was calculated.
Results: One pig died before thrombolysis could be performed. Only with ST-T was residual thrombus mass in the test limb normalized
to control, residual thrombus index (RTI), consistently less than unity. The median RTI of this group was 0.50 (range 0.39–0.97)
compared with 1.22 (0.64–1.38) for ST-P and 0.88 (0.37–1.13) for CI. Compared with contralateral controls, a lower grade of
residual thrombosis in tributaries was observed in test limbs at more venous sites with ST-T (8/20; 95% confidence interval
5–13) and ST-P (9/20; confidence interval 5–13) than with CI (2/20; confidence interval 0–5) (p= 0.04). A trend toward lower thrombolysis scores was observed with ST-T (p = 0.08). Systemic fibrinogenolysis was not observed in any of the groups. Changes in coagulation parameters during thrombolysis were
similar irrespective of treatment protocol.
Conclusions:“Transthrombic” sequestrated thrombolysis may offer some advantages over conventional selective infusion for the treatment
of acute DVT. However further refinements will be necessary before it can be considered an alternative to the latter. 相似文献
10.
Sumit Roy Frank Brosstad Kjell S. Sakariassen 《Cardiovascular and interventional radiology》1999,22(5):403-410
Purpose: To evaluate in a porcine model of acute deep vein thrombosis (DVT) the efficacy of dalteparin and antithrombin with respect
to heparin for local adjuvant therapy during selective thrombolysis, and the utility of nitroglycerin and iloprost as heparin
supplements.
Methods: DVT was induced in both hind limbs using a previously described technique (n = 20). Thirty minutes later, the animal was heparinized (2500 IU IV), and bilateral sequestrated thrombolysis was performed using
8 mg alteplase: both external iliac veins were endoluminally occluded with Swan-Ganz catheters, and a multi-sideport infusion
wire coaxially introduced through each catheter and advanced into the ipsilateral popliteal vein. In the control limbs, tissue
plasminogen activator (tPA) 8 mg was injected as 0.8-ml boluses at 3-min intervals for 2 hr as a 0.25-mg/ml solution containing
heparin 50 IU/ml (n = 20). On the contralateral side, heparin was substituted with either dalteparin 50 IU/ml (n = 5) or antithrombin 12.5 IU/ml (n = 5), or supplemented with either nitroglycerin 0.075 mg/ml (n = 5) or iloprost (150 ng/ml) (n = 5). Blood samples were taken at predetermined intervals to measure the activated partial thromboplastin time (aPTT), prothrombin
time (PT), and fibrinogen concentration. At autopsy, the thrombus mass in the iliofemoral veins was measured, and the extent
of residual thrombosis in the venous tributaries graded at four sites.
Results: Bilateral thrombolysis was successfully completed in all animals. The median thrombus mass in the iliofemoral veins after
thrombolysis was 0.48 g (range 0.06–1.58 g), 0.95 g (0.59–1.29 g), 0.74 g (0.52–0.96 g), and 0.29 g (0.0–0.77 g) for dalteparin,
antithrombin, iloprost, and nitroglycerin respectively, as compared with 0.53 g (0.18–0.88 g) (p = 0.69), 0.97 g (0.46–1.15 g) (p = 0.69), 0.53 g (0.48–1.10 g) (p = 0.69), and 0.18 g (0.13–1.04 g) (p = 0.5) for the respective controls. Likewise, the severity of residual thrombosis in the venous tributaries was not affected by
the constituents of adjuvant therapy. Nitroglycerin induced a small drop in blood pressure, which was transient. The temporal
change in aPTT was similar in all four groups. Invariably PT progressively shortened during thrombolysis (p = 0.0001); this effect was somewhat blunted with antithrombin. Fibrinogen levels demonstrated a time-dependent increase (p = 0.004) that was not influenced by the adjuvant therapy used.
Conclusions: Dalteparin or antithrombin demonstrated no appreciable advantage over heparin as local adjuvant therapy for selective venous
thrombolysis. Supplementation of heparin with iloprost or nitroglycerin also had virtually no effect on thrombolytic efficacy. 相似文献
11.
Noboru Terayama Osamu Matsui Masumi Kadoya Jun Yoshikawa Toshifumi Gabata Shiro Miyayama Tsutomu Takashima Kenichi Kobayashi Isao Nakanishi Yasuni Nakanuma 《Cardiovascular and interventional radiology》1997,20(6):457-461
Purpose: To assess the histologic findings associated with stenosed and occluded transjugular intrahepatic portosystemic shunt (TIPS)
tracts.
Methods: Four TIPS tracts within three autopsy livers were histologically studied for vascular components by routine staining and
immunohistochemical staining. TIPS had been performed for bleeding from esophageal varices in patients with cirrhosis of the
liver.
Results: Two TIPS, examined on days 4 and 53, showed occlusion by fibrin thrombus. In the former, no endothelial cells were detected,
but coagulative necrosis of hepatocytes was found in the surrounding liver. In the latter, bile pigments were seen on the
luminal surface. In the two other TIPS without tract occlusion, examined on days 49 and 293, a layer of endothelial cells,
proliferation of smooth muscle cells, and deposition of an extracellular matrix such as collagen were confirmed. In the tract
examined on day 293, there was protrusion of hepatocytes into the lumen through the stent wires.
Conclusion: Short- and midterm TIPS occlusions were caused by thrombus forming after necrosis of hepatocytes and bile leakage, respectively.
Long-term TIPS stenosis was associated with a combination of pseudointimal hyperplasia and ingrowth of hepatocytes.
Received: 0/00/00/Accepted: 0/00/00 相似文献
12.
Massive Pulmonary Embolism: Treatment with Thrombus Fragmentation and Local Fibrinolysis with Recombinant Human-Tissue Plasminogen Activator 总被引:8,自引:0,他引:8
Klaus Wilhelm Stock Augustinus Ludwig Jacob Karl Jakob Schnabel Georg Bongartz Wolfgang Steinbrich 《Cardiovascular and interventional radiology》1997,20(5):364-368
Purpose: To report the results of thrombus fragmentation in combination with local fibrinolysis using recombinant human-tissue plasminogen
activator (rtPA) in patients with massive pulmonary embolism.
Methods: Five patients with massive pulmonary embolism were treated with thrombus fragmentation followed by intrapulmonary injection
of rtPA. Clot fragmentation was performed with a guidewire, angiographic catheter, and balloon catheter. Three patients had
undergone recent surgery; one of them received a reduced dosage of rtPA.
Results: All patients survived and showed clinical improvement with a resultant significant (p < 0.05) decrease in the pulmonary blood pressure (mean systolic pulmonary blood pressure before treatment, 49 mmHg; 4 hr
after treatment, 28 mmHg). Angiographic follow-up in three patients revealed a decrease in thrombus material and an increase
in pulmonary perfusion. Two patients developed retroperitoneal hematomas requiring transfusion.
Conclusion: Clot fragmentation and local fibrinolysis with rtPA was an effective therapy for massive pulmonary embolism. Bleeding at
the puncture site was a frequent complication.
Received: 0/00/00/Accepted: 0/00/00 相似文献
13.
Jean-Paul Beregi Alain Prat Serge Willoteaux Marc-Antoine Vasseur Valérie Boularand Frédéric Desmoucelle 《Cardiovascular and interventional radiology》1999,22(1):13-19
Purpose: To evaluate initial and midterm results of percutaneous treatment of peripheral aneurysms using covered stents.
Methods: Between June 1994 and December 1997 we used covered stents (EndoPro System or Passager) on 19 patients with peripheral aneurysms
(7 iliac, 5 subclavian, 3 femoral, 3 popliteal, 1 carotid).
Results: Successful aneurysm exclusion was achieved in 18 of 19 patients (95%). In the short term (<30 days), one patient died of
puncture site hemorrhage complicated by myocardial infarction; two femoral stents were surgically removed because of leakage.
At subsequent follow-up (mean 20 months) two further unrelated deaths occurred. At 1 year (intention-to-treat) the stent was
patent in 13 of 19 patients (68%) and the aneurysm was excluded in 17 of 19 (89%).
Conclusion: Treatment of peripheral aneurysms with covered stents has a high rate of immediate procedural success. Continued exclusion
of the aneurysms is achieved in a large proportion of patients but there is a relatively high rate of stent thrombosis. 相似文献
14.
Gastric and Duodenal Stents: Follow-Up and Complications 总被引:11,自引:0,他引:11
Isabel Teresa Pinto Pabón Laura Paúl Díaz Juan Carlos Ruiz de Adana Julio López Herrero 《Cardiovascular and interventional radiology》2001,24(3):147-153
Purpose: To assess the efficacy of self-expanding metallic stents in treating inoperable gastric and duodenal stenoses during follow-up
and to evaluate the complications encountered.
Methods: A total of 31 patients suffering from gastroduodenal obstruction (29 malignant, 2 benign) were treated with a self-expanding
metallic stent (Wallstent). In 24 cases insertion was by the peroral route, in seven cases via gastrostomy.
Results: All the strictures were successfully negotiated under fluoroscopic guidance without having to resort to endoscopy. A total
of 27 patients (87%) were able to resume a regular diet, a soft diet, or a liquid diet orally. Complications included one
case of stent malpositioning, one case of leakage of ascitic fluid through the gastrostomy orifice, one case of perforation
and fistula to the biliary tree, and two cases of hematemesis. In two patients (6%) additional stents were implanted to improve
patency. In all patients follow-up was maintained until death. Recurrence of symptoms immediately before death occurred in
seven cases (23%). Mean survival time of patients was 13.3 weeks (SE ± 4.6).
Conclusions: The deployment of gastroduodenal stents resulted in good palliation of inoperable gastric and duodenal stenoses. Certain
technical aspects, e.g., adaptation of stents to bowel morphology, is critical to proper stent function and avoidance of complications. 相似文献
15.
Wildberger JE Schmitz-Rode T Haage P Pfeffer J Ruebben A Günther RW 《Cardiovascular and interventional radiology》2001,24(1):53-56
Purpose: To evaluate the effectiveness of ultrasound thrombolysis in occluded hemodialysis access shunts using an in vitro model.
Methods: Thrombosed hemodialysis accesses were simulated by clotted bovine blood in a flow model (silicone tubing; inner diameters
4, 6, and 9 mm). After retrograde and antegrade sheath placement (7 Fr), mechanical thrombolysis was performed using an ultrasound
probe (Acolysis, Angiosonics, Morrisville, NC, USA). The tip of the device measured 2.2 mm in diameter. During sonication,
the catheter was moved slowly back and forth using an over-the-wire system. Thirty complete occlusions [tubing diameters 4
mm (n = 12), 6 mm (n = 12), 9 mm (n = 6)] were treated. Initial thrombus weights were 3.5 (± 0.76) g, 7.7 (± 1.74) g, and 19.4 (± 2.27) g for the three diameters.
Maximum sonication time was 15 min for each probe.
Results: With this device, we were able to restore a continuous lumen in all 12 occluded 4∼mm silicone tubes. No wall-adherent thrombi
remained after sonication for 3.5–9.6 min. In hemodialysis access models with diameters of 6 mm, thrombus fragments persisted
in 25% (3/12 accesses). These were located in the medial portion of the access loop and near to the puncture sites. However,
flow was re-established after 5.0–13.0 min of treatment in all settings. Mechanical dissolution of thrombus material failed
in five of six access models with diameters of 9 mm, even though ultrasound energy was applied for the maximum of 15 min.
Conclusion: In a clotted hemodialysis shunt model, successful ultrasound thrombolysis was limited to small access diameters and small
amounts of thrombus. 相似文献
16.
Joanne Latimer Sadeeq M. Bawa Colin J. Rees Mark Hudson John D. G. Rose 《Cardiovascular and interventional radiology》1998,21(3):234-239
Purpose: To assess the medium-term outcome of transjugular intrahepatic portosystemic stent shunts (TIPSS) by measuring the incidence
of shunt obstruction or failure during routine surveillance and the number of interventions performed.
Methods:This is a retrospective study covering a 4-year period, from 1992 to 1996, during which 102 TIPSS procedures were performed.
Indications for treatment were variceal bleeding (76%) and refractory ascites (24%). Follow-up protocol after TIPSS included
transfemoral or transjugular portal venography and measurement of portosystemic pressure gradient (PPG) at 3 months, 12 months,
and then at yearly intervals. The results of the first 155 venograms on 62 patients (mean follow-up 14 months) have been reviewed
and Kaplan-Meier analysis performed.
Results: One hundred and thirty-seven of 155 (88%) examinations showed patent shunts. Fifty-six of 137 (41%) of the patent TIPSS had
elevated PPG with signs of stenosis. The majority (41/56) of shunt stenoses with elevated pressure gradients were related
to neointimal hyperplasia in the hepatic venous aspect of the shunt. Interventions used to reduce the pressure gradient or
to restore patency included: angioplasty (62/102 interventions), additional stents (21/102), a second TIPSS procedure (2/102),
and thrombolysis or thrombectomy (4/102). The primary patency rate was 66% at 1 year (52% at 2 years). Primary assisted patency
was 72% at 1 year (58% at 2 years). Secondary patency was 86% at 1 year (63% at 2 years).
Conclusion: The majority of TIPSS shunts will remain patent when regular portal venography, with appropriate intervention, is undertaken.
Although there is a high reintervention rate this mainly takes the form of balloon angioplasty. 相似文献
17.
Duncan F. Ettles M.D. MRCP FRCR Alastair W. MacDonald Paul A. Burgess Anthony A. Nicholson John F. Dyet 《Cardiovascular and interventional radiology》1998,21(6):475-480
Purpose: To assess the feasibility and efficacy of directional atherectomy in the treatment of iliac stent stenosis or occlusion and
to evaluate the histologic composition of excised atherectomy specimens.
Methods: Directional atherectomy of six occluded and 10 severely stenosed iliac stents was undertaken in 12 patients at a mean interval
of 28 months (range 3–69 months) after stent insertion for occlusive aortoiliac disease. In cases of stent occlusion, atherectomy
was preceded by low-dose thrombolysis. In all patients stent clearance with return of femoral pulses was achieved within 24
hr and there were no significant complications. All excised specimens were sent for histologic examination.
Results: Eleven patients (92%) remain symptom free with unlimited walking distance at a mean follow-up interval of 11.5 months (range
3–31 months) after treatment. Histologic examination revealed typical myointimal hyperplasia at three excision sites, intimal
fibrosis at three sites, atheroma at four sites and organized thrombus at six sites.
Conclusion: Atherectomy offers an effective treatment in iliac stent occlusion and restenosis with no significant adverse effects. Debulking
of these lesions seems to offer a more logical approach than simple balloon angioplasty. Clinical and duplex follow-up confirms
satisfactory outcome within the first year but longer-term results are not yet known. The histologic data obtained demonstrate
that stent restenosis and occlusion are likely to be multifactorial, and challenge the assumption that myointimal hyperplasia
is the sole cause of iliac stent occlusion. 相似文献
18.
Jun-Ichiro Sanada Osamu Matsui Jun Yoshikawa Toshihiko Matsuoka 《Cardiovascular and interventional radiology》1998,21(1):45-49
Purpose: To evaluate the effects of bare stents and covered stents on the aortic wall, especially the vasa vasorum.
Methods: Eight bare stents and nine covered stents were placed in the infrarenal aorta of nine dogs. The dogs were euthanized at 4–45
weeks after stent placement. The vasa vasorum was evaluated by microstereoscopy with vascular casting, and the histopathology
of the aortic wall was examined by light microscopy.
Results: In the unstented normal aorta, vasa vasorum nourished the adventitia and the outer media, and the intima and inner media
were avascular. In the stented segment, vascular dilatation and proliferation of vasa vasorum, medial atrophy, and intimal
hyperplasia were observed, more prominent for covered stents than for bare stents.
Conclusion: Intravascular stent placement caused not only medial atrophy and intimal hyperplasia but also proliferation of the vasa vasorum,
probably due to hypoxia in the aortic wall.
Received: 0/00/00/Accepted: 0/00/00 相似文献
19.
Shozo Hirota M.D. Satoshi Ichikawa Shinichi Matsumoto Tomofumi Motohara Tetsuya Fukuda Takeshi Yoshikawa 《Cardiovascular and interventional radiology》1999,22(4):311-314
Purpose: To evaluate the usefulness of interventional radiological treatment for idiopathic portal hypertension.
Methods: Between 1995 and 1998, we performed an interventional radiological treatment in five patients with idiopathic portal hypertension,
four of whom had refused surgery and one of whom had undergone surgery. Three patients with gastroesophageal varices (GEV)
were treated by partial splenic embolization (PSE), one patient with esophageal varices (EV) and massive ascites by transjugular
intrahepatic portosytemic shunt (TIPS) and PSE, and one patient with GEV by percutaneous transhepatic obliteration (PTO).
Midterm results were analyzed in terms of the effect on esophageal and/or gastric varices.
Results: In one woman with severe GEV who underwent three sessions of PSE, there was endoscopic confirmation that the GEV had disappeared.
In one man his EV shrunk markedly after two sessions of PSE. In two patients slight reduction of the EV was obtained with
one application of PSE combined with endoscopic variceal ligation therapy. PTO for GV in one patient resulted in good control
of the varices. All patients have survived for 16–42 months since the first interventional treatment, and varices are well
controlled.
Conclusion: Interventional radiological treatment is effective for patients with idiopathic portal hypertension, whether or not they
have undergone surgery. 相似文献
20.
Fontaine AB Borsa JJ Hoffer E Bloch R So C 《Cardiovascular and interventional radiology》2001,24(5):324-328
Purpose: Comparative evaluation of the biological effects of a silicone-covered stent versus a bare-metal stent, in an animal model.
Methods: Twelve stent implants were placed in the iliac arteries of six adult dogs. Each animal received one 8-mm × 20-mm silicone-covered
stent (Permalume; Boston Scientific Vascular, Watertown, MA, USA), in the right iliac artery and one Wallstent (Boston Scientific
Vascular) of the same diameter and length in the left iliac artery, during systemic anticoagulation. Angiography was performed
before and after implantations. Animals were then allowed to recover and no platelet suppression was given during a 6-week
interval, after which the animals were euthanized. The stented arteries were isolated and pressure-fixed in situ with 10%
buffered formalin at a pressure of approximately 100 mmHg for a period of 1 hr. Two of 12 stented specimens were opened lengthwise
and the luminal surfaces were photographed. Ten of 12 stented arterial segments were encased in methacrylate, then stained
with hematoxylin and eosin. Neointimal thickness was quantified on histologic cross-section, for both bare and covered stents.
The mean neointimal thicknesses were compared for significant difference using a student t-test.
Results: All implants were widely patent at 6-week follow-up angiography. Histologic analysis showed bare metal stents covered by
a thin uniform lining of neointima composed of smooth muscle cells in a hyaline matrix (mean thickness of 189 ± 47 μm). Silicone
covered stents were devoid of neointima. There was no chronic thrombus or mature endothelium noted anywhere upon the internal
silicone surfaces of any of the specimens. There was no foreign body reaction to the silicone cover.
Conclusion: Short-term implantation of a silicone-lined Wallstent in canine iliac arteries is well tolerated. Silicone appears to be
inert at 6 weeks in this experimental application. 相似文献