Risk factor analysis of new brain lesions associated with carotid endarterectmy

PURPOSE: Carotid endarterectomy (CEA) is the standard treatment for carotid artery stenosis. New brain ischemia is a major concern associated with CEA and diffusion weighted imaging (DWI) is a good imaging modality for detecting early ischemic brain lesions. We aimed to investigate the surgical complications and identify the potential risk factors for the incidence of new brain lesions (NBL) on DWI after CEA. METHODS: From January 2006 to November 2011, 94 patients who had been studied by magnetic resonance imaging including DWI within 1 week after CEA were included in this study. Data were retrospectively investigated by review of vascular registry protocol. Seven clinical variables and three procedural variables were analyzed as risk factors for NBL after CEA. RESULTS: The incidence of periprocedural NBL on DWI was 27.7%. There were no fatal complications, such as ipsilateral disabling stroke, myocardial infarction or mortality. A significantly higher incidence of NBL was found in ulcer positive patients as opposed to ulcer negative patients (P = 0.029). The incidence of NBL after operation was significantly higher in patients treated with conventional technique than with eversion technique (P = 0.042). CONCLUSION: Our data shows CEA has acceptable periprocedural complication rates and the existence of ulcerative plaque and conventional technique of endarterectomy are high risk factors for NBL development after CEA.

Comparative results of conventional and eversion carotid endarterectomy

PURPOSE: Comparative results of conventional carotid endarterectomy (cCEA) and eversion carotid endarterectomy (eCEA) have been reported in many studies. But in Korea, there have been no reports to compare the outcome of the two techniques. Thus, we investigated the results of eCEA compared to cCEA in Yeungnam University Medical Center. METHODS: A total of 120 subjects who underwent CEA were included in this study. Of them, cCEAs were performed in 63 patients and eCEAs were performed in 57 patients. We analyzed the results divided into the early (within 30 days after surgery), midterm (from 30 days up to 1 year after surgery) and late (over 1 year after surgery). RESULTS: Mean age of the patients was 65.9 +/- 7.1 years in cCEA group and 66.8 +/- 7.7 years in eCEA group (P = 0.523). Carotid shunt frequency was higher in the cCEA group (39.7% vs. 19.3%, P = 0.015). There were no statistical differences in the early complications with the exception of a significantly higher risk for new brain lesions in the cCEA group (34.9% vs. 14.0%, P = 0.008). The frequency of complication was same between cCEA group and eCEA group in the midterm. Although there was no statistical significance, the frequency of late complications was higher in the cCEA group compared to eCEA group. Mean follow-up duration was 29.4 +/- 23.5 months. CONCLUSION: These data showed that eCEA was an acceptable procedure and had some advantage compared to cCEA in the aspect of the early and late complication.

The results of aspiration thrombecomy in the endovascular treatment for iliofemoral deep vein thrombosis / 대한외과학회지

PURPOSE: The aim of this study is to evaluate the results of aspiration thrombectomy (AT) in the endovascular treatment for iliofemoral deep vein thrombosis (DVT) through the comparison of catheter directed thrombolysis (CDT) alone group and CDT with AT group. METHODS: From November 2001 to April 2011, 100 patients received endovascular treatment with CDT alone or CDT with AT for iliofemoral DVT at Yeungnam University Medical Center. We compared procedure, clinical outcomes and complications between the two groups. RESULTS: The mean age of patients was 60.48 +/- 14.57 years. The patients consisted of 41 men and 59 women. CDT alone and CDT with AT were performed in 29 and 71 patients, respectively. The mean procedural time of the CDT-alone group was longer than the CDT with AT group (P < 0.001) and dose of urokinase used during the procedure significantly decreased in the CDT with AT group (P < 0.001). There were no statistically significant differences in clinical outcomes between the two groups. Cases of pulmonary embolism was not noted in each group in our series, but entrapped thrombus during procedure was noted in 6 of 37 in the CDT with AT group and 0 of 9 in the CDT-alone group among 46 patients with prophylactic inferior vena cava (IVC) filter insertion. CONCLUSION: In conclusion, CDT with AT is safe and effective for the treatment of an acute iliofemoral DVT. In AT treatment, prophylactic IVC filter insertion should be considered for the prevention of pulmonary embolism by floating thrombi.

The Results of Eversion Endarterectomy for Carotid Artery Stenosis / 대한혈관외과학회지

PURPOSE: Potential benefits of eversion carotid endarterectomy (eCEA) compared with conventional carotid enderterectomy (cCEA) are more simple and faster reanastomosis with a low risk of restenosis. However, in Korea, eCEA is not popular having only one report of eCEA. This study aimed to investigate the results of eCEA. METHODS: From July 2008 to September 2010, authors performed 36 eCEAs for patients with carotid artery stenosis in our hospital. Patients' demographics and clinical data were retrospectively reviewed. Regarding early (<30 days) results including the frequency of postoperative stroke, myocardial infarction, cerebral hyperperfusion syndrome, bleeding, cranial nerve palsy, new brain lesions (NBLs) on diffuse-weighted MRI (DW-MRI) and mortality were examined. Mid-term results such as stroke, death and restenosis after over thirty days were also examined. RESULTS: Mean age was 66.6 years old and 88.9% of the patients were male. Twenty-four patients (66.7%) had a previous neurological event in the preceding 6 months. A carotid shunt was used in 3 cases (8.3%) and mean carotid clamping time was 25.4 minutes. One case (2.8%) of non-disabling ipsilateral stroke, 1 case (2.8%) of wound hematoma and 1 case (2.8%) of cranial nerve palsy developed after operation. DW-MRI was conducted in 27 patients (75.0%) and NBLs were detected in 4 patients (11.1%). One case (2.8%) of restenosis was discovered during the follow-up period (mean, 9.0 months), and there were no strokes or death. CONCLUSION: Early and mid-term postoperative stroke and complication rates of eCEA were acceptable in our series. However, to assess efficacy of eCEA, further large-volumed and long-term follow-up studies are needed.

Predictor of Recanalization in Lower Extremity Deep Vein Thrombosis / 대한혈관외과학회지

PURPOSE: Residual thrombus is known as a risk factor of recurrent deep vein thrombosis (DVT) and may induce functional impairment of the affected vein and post-thrombotic syndrome. This study was constructed to examine recanalization rates in patients with DVT at 6 months after treatment and to identify the predictors of recanalization. METHODS: From June 2006 to December 2009, we retrospectively reviewed the medical records of 40 patients who underwent a follow-up duplex scan or computed tomography venography at 6 months following treatment. The degree of recanalization on duplex scans was categorized as "complete recanalization", "partial recanalization" and "occlusion". Univariate and multivariate analyses were conducted to identify the independent predictors of "complete recanalization". RESULTS: The mean age of individuals within the study was 59 years (33-85 years) and 40% was the participants were female. Ten patients (25%) had transient risk factors, such as immobilization, recent trauma, orthopedic or major surgery. Complete recanalization, partial recanalization, and occlusion at 6 months were obtained in 58%, 25%, 18% (50%, 31%, 19% in anticoagulation alone group and in 71%, 14%, 14% in catheter-directed thrombolysis group, P=0.489, respectively). With regards to the multivariate analysis including the binary logistic regression model, the presence of transient risk factors was the only independent predictor of "complete recanalization" (P=0.041). CONCLUSION: In our series, complete recanalization rate at 6 months was 58%. Furthermore, complete modulation of transient risk factors during the follow up period seems to be an important predictive factor concerning complete recanalization.

The early and mid-term results of carotid artery stenting in high-risk patients / 대한외과학회지

PURPOSE: This study aimed to investigate early and mid-term outcomes of carotid artery stenting (CAS). METHODS: We retrospectively reviewed 111 patients who were treated for carotid stenosis between October 2004 and December 2009 (42 CASs and 69 carotid endarterectomies [CEAs]). RESULTS: CAS group was older than CEA group (70 years vs. 67 years, P = 0.001). Coronary artery disease and high lesion above the 2nd cervical vertebral body were more common in CAS group (29% vs. 13%, P = 0.002; 4% vs. 24%, P = 0.004). The 30-days stroke rate was higher in CAS group (10% vs. 1% in CEA group, P = 0.067, Fisher's exact test). New brain lesions on diffusion-weighted magnetic resonance imaging were more common in CAS group (48% vs. 20% in CEA group, P = 0.002, chi-square test). The 1-, 3-year freedom from stroke were 91%, 84% in CAS group and 99%, 99% in CEA group (P = 0.007, log-rank test). Univariate analysis showed that female gender and age > 70 years were related with postprocedural neurological complications (P = 0.046 and P = 0.007, log-rank test). However, none were independent risk factors on multivariate analysis. CONCLUSION: In our series, the rates of peri-procedural neurological complications in CAS group were significantly high. These results suggest that more experience and restricted patient selection will be needed for CAS.

Adventitial cystic disease of common femoral vein / 대한외과학회지

Adventitial cystic disease (ACD) of venous system is an extremely rare condition. Very few reports of ACD in venous system have been described. In this report we discuss two cases of common femoral vein ACD that presented with a swollen leg by the obstruction of the vein. Ultrasound imaging showed the typical hypoechoic fluid filled cyst with a posterior acoustic window. Computed tomography scan and ascending venogram showed a stenosis to flow in the common femoral vein caused by an extrinsic mass. Trans-adventitial evacuation of cyst with removal of vein wall was performed for both cases. During operation we found the gelatinous material in the cysts arising in the wall of the common femoral vein and compressing the lumen. The patients were released after short hospitalization and have remained symptom free with no recurrence.

FDG Uptake Pattern of a Prosthetic Graft without Infection on a PET/CT Scan

PURPOSE: A prosthetic graft infection is a rare but often disastrous complication during vascular surgery. Diagnosis of a prosthetic graft infection is not always easy, particularly with a low virulent bacterial infection or in a deeply placed graft in the retroperitoneal space. Recently, fludeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) has been proposed as a diagnostic modality for prosthetic graft infection. However, some reports have indicated that high FDG uptake occur in grafts without infections. This study analyzed FDG uptake patterns in prosthetic grafts of asymptomatic patients. METHODS: We reviewed 14,545 patients who had received PET/CT in a tertiary hospital between July 2007 and March 2010. Of them, 11 patients who had undergone previous bypass surgery with a prosthetic graft were identified. Four underwent an aortic bypass and the others received lower extremity bypass grafting. PET/CT images and patient clinical data were reviewed retrospectively. The maximum standardized uptake value (SUVmax, A) in the graft, the mean SUV (SUVmean, B) of the blood-pool, and the target-to-background ratio (T/B, A/B) were calculated. RESULTS: The mean duration between bypass grafting and the PET/CT scan was 21 months (range, 1~80 months). No clinical evidence of graft infection was observed in any of the patients. PET/CT revealed an uneven, diffuse FDG uptake pattern on the grafts, and the mean T/B was 2.0 (range, 0.9~4.6). T/B was greater than 2.0 in six patients (55%). CONCLUSION: A prosthetic graft without an infection can result in increased FDG uptake during PET/CT. A further prospective study is necessary to evaluate the usefulness of FDG PET/CT for diagnosing a prosthetic graft infection.

The Results of Aspiration Thrombectomy for the Endovascular Treatment of Ileofemoral Deep Vein Thrombosis

PURPOSE: This study was performed to evaluate the effect of aspiration thrombectomy for the treatment of ileofemoral deep vein thrombosis. METHODS: We reviewed the records of sixty-two patients who were treated with catheter-directed thrombolysis (CDT) at our institution between November 2001 and October 2007. The patients were divided into two groups: those who were treated by CDT with aspiration thrombectomy (AT) (the aspiration group; 33 patients) or those who were treated with using CDT alone (the CDT alone group; 29 patients). The obtained data included the demographics, the procedural details, the periprocedural evaluation and the thrombus resolution. RESULTS: The treatment time with using CDT only was 40.93+/-15.59 hours compared with 23.18+/-8.22 hours with using AT (P<0.001). The mean dose of urokinase with using CDT only was 2.48+/-0.82 million IU as compared with 1.60+/-0.54 million IU with using AT (P<0.001). The use of AT did not improve the overall lytic success (P=0.084), but more patients had complete thrombus resolution (13 vs. 22 patients, respectively). There was no difference in symptom improvement or the long term patency rate between the two groups. There was no major morbidity or mortality. The prophylactic IVC filters were inserted in 31 patients and entrapped thrombi were founded in 3 patients of the aspiration group. Evidence of venous reflux was identified in the CDT only group (3 patients; 10.4%). CONCLUSION: These results suggest that the use of AT offers more effective thrombus removal in less time and with using a lower dose of thrombolytic agents. When performing AT treatment, prophylactic IVC filter insertion should be considered for preventing floating thrombi.

Temporary Inferior Vena Cava Filter Placement in Patients withDeep Vein Thrombosis

PURPOSE: To evaluate the effectiveness and complications of temporary inferior vena cava filters in deep vein thrombosis. METHOD: We retrospectively evaluated the clinical data of 35 patients who underwent percutaneous insertion of a temporary, retrievable IVC filter during treatment of deep vein thrombosis between 2003 and 2006. A Tulip(R) was used in 25 patients, and an OptEase(R) was used in 10 patients. Indications for filter insertion included thrombolytic therapy (n=29), long floating IVC thrombosis (n=4), and pulmonary thromboembolism history with recurrent venous-thromboembolism (n=2). Deep vein thrombosis was treated with an endovascular procedure in 33 patients and anticoagulation therapy in 2 patients. RESULT: Complete symptom resolution was achieved in all patients. The temporary IVC filters were successfully retrieved in 28 of 35 patients (mean duration of filter placement: 9.57 days), but retrieval failed in 7 patients (thrombus in filter, 3 cases; remnant IVC thrombosis, 1 case; remnant iliac vein thrombosis/venous stenosis in high risk patient, 2 cases; in-hospital mortality due to underlying heart disease, 1 case). There were no cases of pulmonary embolism and no serious IVC filter-related complications during insertion, retraction, or remnant IVC filter follow-up. CONCLUSION: Temporary, retrievable IVC filters were effective in the prevention of pulmonary embolism. Further investigations are necessary to determine long-term outcome data for filters left in place.

Catheter Directed Thrombolysis for Deep Vein Thrombosis during the First Trimester of Pregnancy: Two Case Reports

Anticoagulation with heparin has been the standard management therapy of deep vein thrombosis during pregnancy. Pregnancy is generally considered as a contraindication for thrombolysis. However, anticoagulation therapy alone does not protect the limbs from post-thrombotic syndrome and venous valve insufficiency. Catheter-directed thrombolysis, combined with angioplasty and stenting, can remove the thrombus and restore patency of the veins, resulting in prevention of post-thrombotic syndrome and valve insufficiency. We report successful catheter-directed thrombolysis and stenting in two early gestation patients with a deep vein thrombosis of the left lower extremity.

Comparison of the Clinical Results between Endovascular and Open Bypass Surgery for Treating Iliac Artery Occlusion

PURPOSE: This study was constructed to review our experience for the treatment for iliac artery occlusion/stenosis with performing angioplasty/stenting and open bypass surgery. METHODS: We retrospectively evaluated the 86 primary endovascular and open bypass procedures that were done for iliac artery occlusion/stenosis between 2000 and 2005. The data was divided into two groups by the procedure: the endo group (31 limbs, 36%), and the bypass group (55 limbs, 65%). RESULTS: The outcomes were defined according to the reported standards of the Society for Vascular Consensus (TASC). The lesion types were significantly more severe in the patients in the bypass group (P=0.000). The initial technical & clinical success rates were 100% in both groups. The cumulative 48-month primary & secondary patency rates were 76.1% and 95.2% in the endo group and 78.0% and 93.8% in the bypass group, respectively. The perioperative complication rates were 6% in the endo group and 9% in the bypass group, respectively. The mean hospital stay was more significantly shorter in the endo group (5.4 days vs. 15.1 days, respectively, p=0.000). CONCLUSION: The treatment of iliac artery lesion with angioplasty/stenting was a safe and effective method in our experience. Selective angioplasty/stenting may be preferable to bypass surgery for treating TASC A and B type iliac artery occlusions.

The Effects of Foam Sclerotherapy for the Treatment of Lower Limb Varicose Veins

PURPOSE: To evaluate the effectiveness of foam sclerotherapy, we compared the clinical data and results of foam sclerotherapy with conventional sclerotherapy. METHOD: Ninety-three cases of varicose veins were retrospectively reviewed; these were treated by sclerotherapy from January 2000 to September 2005 (women: 82 cases, men: 12 cases, mean age: 43.7 years old). The enrolled cases were divided into the conventional sclerotherapy (CS) group (n=53) and the foam sclerotherapy (FS) group (n=40) according to the applied technique. We assessed the results with the disappearance scoring scale (DSS) and the satisfaction scoring scale (SSS). RESULT: In DSS, complete disappearance was reported as 28.3% by physicians and 30.2% by the patients in CS group and as 47.5% and 52.5% in the FS group, respectively. On the SSS, a satisfaction score scale above 3 (4: Good, 5: Very good) was reported for 79.1% in the CS group and 90.0% in the FS group, retrospectively. The average amounts of sclerosants used were significantly lower in the FS group (1.2+/-0.4 vials) than in the CS group (2.1+/-0.5 vials)(P=0.001). Post injection complications were retrospectively observed in 16.1% of all the patients, in 20.7% of the CS group and in 10.0% of the FS group. CONCLUSION: Sclerotherapy is a very effective and sufficient treatment for telangiectases or reticular varicose veins. Especially, foam sclerotherapy is more effective than conventional liquid sclerotherapy for the clinical results and the patient satisfaction, and it shows a with lower incidence of complications.

The Effects of Foam Sclerotherapy for the Treatment of Lower Limb Varicose Veins

PURPOSE: To evaluate the effectiveness of foam sclerotherapy, we compared the clinical data and results of foam sclerotherapy with conventional sclerotherapy. METHOD: Ninety-three cases of varicose veins were retrospectively reviewed; these were treated by sclerotherapy from January 2000 to September 2005 (women: 82 cases, men: 12 cases, mean age: 43.7 years old). The enrolled cases were divided into the conventional sclerotherapy (CS) group (n=53) and the foam sclerotherapy (FS) group (n=40) according to the applied technique. We assessed the results with the disappearance scoring scale (DSS) and the satisfaction scoring scale (SSS). RESULT: In DSS, complete disappearance was reported as 28.3% by physicians and 30.2% by the patients in CS group and as 47.5% and 52.5% in the FS group, respectively. On the SSS, a satisfaction score scale above 3 (4: Good, 5: Very good) was reported for 79.1% in the CS group and 90.0% in the FS group, retrospectively. The average amounts of sclerosants used were significantly lower in the FS group (1.2+/-0.4 vials) than in the CS group (2.1+/-0.5 vials)(P=0.001). Post injection complications were retrospectively observed in 16.1% of all the patients, in 20.7% of the CS group and in 10.0% of the FS group. CONCLUSION: Sclerotherapy is a very effective and sufficient treatment for telangiectases or reticular varicose veins. Especially, foam sclerotherapy is more effective than conventional liquid sclerotherapy for the clinical results and the patient satisfaction, and it shows a with lower incidence of complications.

OKT3-Induced Cytokine Release Attenuation by Interleukin-10

Purpose: OKT3 is a very powerful immunosuppressive drug in acute allograft rejection treatment but its side-effects such as fever, nausea, vomiting, and pulmonary edema are strongly linked with its inducing cytokines such as tumor necrosis factor alphaTNF-alpha, interleukin-6(IL-6), and interferon-gammaIFN-gamma. Interleukin-10(IL-10) inhibits proinflammatory cytokines which are produced by activated monocyte/ macrophages and prevents production of cytokines in acute inflammatory states. The purpose of this study is to determine the effect of exogenous administration of the anti- inflammatory cytokine, IL-10 on TNF-alpha IL-6, and IFN-gammaproduction and pulmonary injury after OKT3 injection. METHODS: For experiment, Sprague-Dawley rat weighed 300~400 gm was injected either OKT3(0.6mg/kg i.v.) only or recombinant IL-10(0.5microgram/rat i.p. one hour before the injection of OKT3(IL-10/OKT3). The rats were divided into three groups; control group(n=5); normal saline injected group(1.0ml/rat i.v.), OKT3 group(n=5); OKT3 only injected group, and IL-10/OKT3 group; IL-10 plus OKT3 injected group. After two hours of injection, all animals were sacrificed and submitted for a study of serologic and histologic changes. Student t-test was used for statistical analysis. To evaluate the cytokine production the serum levels of TNF-alpha, IL-6, and IFN-gamma level were measured. The serum levels of TNF-alpha, IL-6, and IFN-gamma were also significantly decreased in IL-10/ OKT3 group(109.6+/-38.0, 65.2+/-14.1, 96.2+/-17.3pg/ml) compared with OKT3 group(399.8+/-71.4, 155.4+/-45.1, 297+/-87.0pg/ml)(p<0.05). To determine the pulmonary injury, wet/dry ratio and microscopic findings for the lung tissue were analyzed. RESULTS: The wet/dry ratio of the lung tissue was significantly decreased in IL-10 /OKT3 group (3.52+/-0.31) compared with OKT3 group(4.16+/-0.48)(p<0.05). Microscopic findings of lung tissue revealed severe neutrophilic infiltration and microvascular congestion in the OKT3 group, but in IL-10/ OKT3 group, neutrophilic infiltration and microvascular congestion were decreased. CONCLUSION: In this study the inhibitory effect of IL-10 on the production of proinflammatory cytokines by OKT3 treatment was significant. This results suggest that the exogenous IL-10 injection may decrease the complications associated with OKT3 treatment of allograft rejection in organ transplantation.

Report of Nation-wide Questionnaire Survey for Abdominal Aortic Aneurysm Treatment in Korea

While endovascular aneurysm repair (EVAR) is prevailing for the treatment of abdominal aortic aneurysm (AAA) in modern vascular practice, PURPOSE: we conducted nationwide questionnaire survey to investigate the current status of AAA treatment and their results in Korea. METHOD: We reviewed the replies from 28 hospitals (33 departments) to the questionnaire inquiring annual number, clinical features, mode of treatment and results of AAA patients during the period from Jan. 2000 to Jul. 2004. Results: 980 AAA patients were reported including 292 ruptured AAA (29.8%) and 688 non-ruptured AAA (70.2%). For treatment of AAA, 834 (85.1%) surgical repairs (SRs) and 111 (11.3%) endovascualr aneurysm repairs (EVARs) were performed while 35 patients (3.6%) died of AAA rupture before operation. The locations of AAA were infrarenal in 889 (90.7%), juxtarenal in 62 (6.3%), and suprarenal in 29 patients (3.0%). Among 834 patients undergoing SR, 577 patients (69.2%) had non-ruptured AAAs and 257 patients (30.8%) had ruptured AAAs. Mean operative mortality rate was 4.1% after elective SRs, 30.7% after SR for ruptured AAAs, and 2.3% after EVARs. The reported brand name of stent graft devices were various including domestic custom-made in 56 (50.5%), imported brand in 18 (16.2%) while 37 (33.3%) stent grafts were not reported their brand name. The frequencies of type I and III endoleaks after EVAR were reported 5.8% and 5.8% respectively in 86 patients with an available data. CONCLUSION: SR has been used as a major treatment option in Korea for the treatment of AAA patients while EVAR is increasing. The mortality rate of SR of AAA was comparable to western multi-center trial reports but mortality or morbidity rates of EVAR were unable to know in this questionnaire survey.

The Endovascular Treatment for Iliac Vein Compression Syndrome

PURPOSE: Iliac vein compression syndrome (IVCS), first characterized by Cockett and Thomas in 1965, is the development of iliofemoral deep venous thrombosis due to compression of the left common iliac vein against the spine and pelvic brim by the right common iliac artery. Thrombectomy treatment of the underlying compression is essential if significant long-term sequelae are to be avoided. Surgical treatment options include venous reconstruction or venous bypass, but treatment using endovascular techniques have recently been described. This study was conducted to evaluate the usability of endovascular treatment (esp. thrombolysis with stent insertion) in a venous outflow obstruction resulting from IVCS. METHOD: During a 2-year period, 20 patients (17 women, 3 men; mean age, 60 years) presented with clinical and imaging findings consistent with IVCS. All patients presented with leg edema or pain. The mean duration of symptom onset was 6.6+/-4.4 days, ranging from 1 to 15 days. All patients were evaluated using a Duplex scan, computerized tomography and venography. After the ascending venography had been performed, an infusion catheter system was placed, and urokinase infused locally into the thrombus burden. After near complete clot dissolution, the residual left common iliac vein stenosis was treated by means of angioplasty and the placement of a Wallstent. All patients continued to receive oral warfarin. Patients were followed-up by means of clinical visits, and the stent patency was assessed by means of a Duplex scan or computerized tomography. RESULT: The total dose of urokinase used and the duration of infusion were 2.28+/-0.93 million unit, ranging from 1.00 to 5.20 and 46.8+/-14.8 hours, ranging from 14 to 72 hours, respectively. Grade III (complete lysis) thrombolysis was achieved in 17 patients. All 17 patients successfully received a Wallstent. The initial clinical success was 100%, with complete resolution of symptoms in all patients. One patient, with combined ovarian cancer, had a recurrent symptomatic deep vein thrombosis and complete occlusion of the stent due to thrombosis 2 months after treatment. However, no other patients showed evidence of deep vein thrombosis after treatment. The overall patency rate of the stenting at 18 months was 94.1%. There were no deaths, pulmonary embolism, cerebral hemorrhage or major bleeding complications. CONCLUSION: These results suggested that the treatment of iliac vein compression syndrome, using catheter directed thrombolytic therapy and venous stent insertion, was a safe and effective method at the mid term evaluation. These patients will continue to be followed up with screening tests to further define the long-term patency.

The Effect of Tissue Plasminogen Activator on Intimal Hyperplasia after Balloon Injury to Rat Aorta

PURPOSE: Thrombus formation enhances both neointima formation and clinical restenosis after vascular injury or angioplasty. Thrombotic occlusions and intimal hyperplasia limit the success of vascular reconstructive procedures. Thrombolysis is expected to improve the outcome for both restenosis and acute arterial occlusion after injury. Tissue-type plasminogen activator (tPA) is commonly used clinically, and it is thought to play a critical role in vascular remodeling by mediating intravascular clot lysis and modulating cell migration within the vessel wall. However, there is controversy about the late effects of tPA on the vascular lumen either for preventing or enhancing intima hyperplasia in vivo. Thus, this study was done to evaluate the impact of a clinical infusion of tPA on the neointima formation after a balloon injury. METHOD: Forty male Sprague- Dawley rats weighting of 250~300 gm each were underwent aortic intimal denuation with a 2F balloon catheter. The rats were divided into two groups: the control group (n=20: normal saline infusion), and the*ean IMAR on the 21st day was 1.14+/-0.16 in the control group and 1.10+/-0.11 in the experiment group. The mean IMAR was lower in the experiment group, but the result was not statistically significant. In comparison to the gelatinolytic activity of MMP-9 and, activated MMP-2, there was no significant difference between the two groups. CONCLUSION: These results suggest that the effect of tPA on intimal hyperplasia after balloon injury to rat aorta showed minimal significance.

Effect of Prolonged Thrombus Exposure on the Development of Secondary Venous Wall Changes in a Rat Venous Thrombosis Model

PURPOSE: There is growing evidence that thrombosis and inflammation are closely interrelated and that the inflammatory response may play a role in the development of the syndrome of post-thrombotic, chronic venous insufficiency. A thrombus contains biologically active factors that stimulate cellular and structural alterations and lead to post-thrombotic venous abnormalities. Prolonged exposure to thrombus may result in the development of more severe pathologic conditions. To assess the effect of prolonged thrombus exposure on the development of secondary venous wall changes, the level of D-dimer test and the microscopic findings of thrombosed vein were analyzed in a rat venous thrombosis model. METHOD: The left iliac vein of male Sprague-Dawley rats weighing of 250 to 300 gm were thrombosed by means of either proximal ligation or temporary 24-hour occlusion with a microvascular clamp. The rats were divided into three groups: control group (n=10), thrombosis model by proximal ligation of the iliac vein only; group A (n=10), thrombosis model by proximal ligation of the iliac vein with treatment of low molecular weight heparin (LMWH; Clexane(r) 0.5 mg/kg, s.c.b.i.d); and group B (n=10), thrombosis model by temporary 24-hours clamp of the iliac vein without treatment of LMWH. The vein located 2 cm below from the initial ligation was harvested at time intervals of 7 and 14 days after ligation or clamp. Thrombi were identified by gross findings and indirectly quantitated with D-dimer test. RESULT: The levels of D-dimer test on days 7 and 14 after ligation or occlusion were significantly higher in the control group than in groups A and B (P<0.05). However, gross findings of intraluminal thrombosis were not present only in group B. These findings suggest that injection of LMWH did not prevent the development of thrombi around the ligation area. The neutrophilic infiltration of the perivascular area was evaluated microscopically (Hematoxylin-Eosin stain, x100). Severe perivascular neutrophilic infiltration was found in the control group and group A, whereas in group B neutrophilic infiltration was decreased to a mild or moderate degree. The vein wall thickness was evaluated by counting cells on representative sections through the mid vein area and by direct measuring of the vein wall usinga scale bar. The rat vein walls on days 7 and 14 were significantly thicker in the control group and group A than in group B (P<0.05). CONCLUSION: These results suggest that prolonged exposure of thrombus plays a major role in the development of secondary venous wall changes. However, the injection of LMWH did not prevent the development of secondary venous wall changes during the prolonged exposure of thrombus.

Analysis of the Clinical Factors Affecting Graft Patency Rate after Infrainguinal Arterial Reconstruction

PURPOSE: This study was designed to determine the clinical factors affecting the long-term graft patency of leg arterial bypass for the patients with chronic lower limb arterial occlusion. METHOD: The clinical data of 81 femoro-distal bypasses performed at Yeungnam University Hospital from January 1996 to December 2002 were included for this retrospective study. A Log-Rank test of Kaplan-Meier method and Cox proportional hazard analysis were performed to identify those main effects that were predictive of graft patency. The patients, 79 males and 2 females, ranged from 37 to 81 years of age, with a mean age of 64. The highest incidence occurred among those in their 60s and 70s. Associated diseases were hypertension in 42 cases (51.8%), diabetes mellitus in 15 (18.8%), cardiac disease in 26 (32.1%) and cerebrovascular disease in 6 (7.4%). A history of smoking was noted in 76.5% of the cases. As for the clinical grades of chronic limb ischemia according to SVS/ISCVS classification, 21 limbs (25.9%) were classified as grade I (category 3), 40 (49.4%) as grade II, and 20 (24.7%) as grade III. The site of distal anastomosis was above the knee popliteal artery in 53 limbs (65.4%), below the knee popliteal artery in 8 (9.9%) and tibial artery in 20 (24.7%). As bypass conduit, autologous vein graft was used in 67 limbs (82.7%) and polytetrafluoroethylene (PTFE) graft in 14 (17.3%). There were no hospital mortalities or major perioperative complications. RESULT: From the univariate analysis of 21 clinical variables (age, sex, smoking, hypertension, diabetes mellitus, coronary arterial disease, congestive heart failure, chronic pulmonary disease, cerebrovascular disease, malignancy, hypercholesterolemia, clinical grade of chronic limb ischemia by SVS/ISCVS, level of occlusion, preoperative ankle-brachial index, type of graft, site of distal anastomosis, operation time, status of inflow artery, postoperative ankle-brachial index, clinical outcome criteria by SVS/ISCVS, postoperative anticoagulation therapy), 5 factors were identified as being associated with long-term graft patency: preoperative clinical grade (P=0.03), preoperative ankle-brachial index (P=0.00), level of occlusion (P=0.03), type of graft (P=0.00) and clinical outcome criteria (P=0.00). In multivariate analysis, type of graft, PTFE graft (vs. autologous vein graft, P=0.002), and clinical outcome criteria, minimally improved (vs. moderately, and markedly improved, P=0.029), showed a lower graft patency rate. CONCLUSION: These results suggest that autogenous vein is more acceptable for leg arterial bypass and poor early clinical outcome predicts poor long term graft patency rate.