• International Journal of Vascular Biomedical Engineering
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• v.4 no.2
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• pp.13-18
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• 2006

Direct injection of a fibrinolytic agent to the intra-arterial thrombosis may increase the effectiveness of thrombolysis by enhancing the permeation of thrombolytic agents into the blood clot. Permeation of fibrinolytic agents into a clot is influenced by the surface pressure, which is determined by the injection velocity of fibrinolytic agents. Computational fluid dynamic methods were used in order to predict clot lysis for different jet velocities and nozzle arrangements. Firstly, thrombolysis of a clot was mathematically modeled based on the pressure and lysis front velocity relationship. Direct injection of a thrombolytic agent increased the speed of thrombolysis significantly and the effectiveness was increased as the ejecting velocity increased. The nine nozzles model showed about 20% increase of the lysed volume, and the one and seventeen nozzles models did not show significant differences. Secondly, thrombolysis was modeled based on the enzyme transport and the fluid flow equations, and quasi steady numerical analysis was performed. Clot lysis efficiency was also increased as injection velocity increased.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.226-231
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• 2009

Objective : We describe our clinical experiences and outcomes in patients who had thromboembolic complications occurring during endovascular treatment of intracerebral aneurysms with a review of the literature. The types of thromboembolic complications were divided and the treatment modalities for each type were described. Methods : Between August 2004 and March 2009 we performed endovascular embolization with Guglielmi detachable coils for 173 patients with 189 cerebral aneurysms, including ruptured and unruptured aneurysms at our hospital. Sixty-eight patients were males and 105 patients were females. The age of patients ranged from 22-82 years (average, 58.8 years). We retrospectively evaluated this group with regard to complication rates and outcomes. The types of thromboembolic complications were classified into the following three categories: mechanical obstruction, distal embolic stroke, and stent-induced complications, which corresponded to types I, II, and III, respectively. A comparison of the clinical results was made for each type of complication. Results : Only eight patients had a thromboembolic complication during or after a procedure (4.6%). Of the eight patients, two had a mechanical obstruction as the causative factor; the other three patients had distal embolic stroke as the causative factor. The remaining three patients had stent-induced complications. In cases of mechanical obstruction, recanalization occurred due to the use of intra-arterial thrombolytic agents in one of two patients. Nevertheless, a poor prognosis was seen. In the cases of stent-induced complications, in one of three patients in whom a thrombus developed following stent insertion, a middle cerebral artery territory infarct developed with a poor prognosis despite the use of wiring and an intra-arterial thrombolytic agent. In the cases of distal embolic stroke, all three patients achieved good results following the use of antiplatelet agents. Conclusion : Treatment for thromboemboic complications due to mechanical obstruction and stent-induced complications include antiplatelet and intra-arterial thrombolytic agents; however, this cannot guarantee a sufficient extent of effectiveness. Therefore, active treatments, such as balloon angioplasty, stent insertion, and clot extraction, are helpful.

• Journal of Biomedical Engineering Research
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• v.26 no.3
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• pp.157-161
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• 2005

Direct injection of a fibrinolytic agent to the intraarterial thrombosis may increase the effectiveness of thrombolysis by enhancing the permeation of thrombolytic agents into the blood clot. Permeation of fibrinolytic agents into a clot is influenced by the surface pressure, which is determined by the injection velocity of fibrinolytic agents. In order to calculate the pressure distribution on the clot surface for different jet velocities (1, 3, 5 m/sec) and nozzle arrangements (1, 9, 17 nozzles), computational fluid dynamic methods were used. Thrombolysis of a clot was mathematically modeled based on the pressure and lysis front velocity relationship. Direct injection of a thrombolytic agent increased the speed of thrombolysis significantly and the effectiveness was increased as the ejecting velocity increased. The nine nozzles model showed about $20\%$ increase of the lysed volume, and the one and seventeen nozzles models did not show significant differences. The wall shear stress decreased as the number of nozzles increased, and the wall shear stress in most vessel wall was lower than 25 Pa. The results implied that thrombolysis could be accelerated by direct injection of a drug with the moderate velocity without damaging the blood vessel wall.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.275-283
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• 2018

Ischemic stroke can result from blockage of blood vessels, forming fibrin clots in the body and causing irreparable brain damage. Remedial thrombolytic agents or anticoagulants have been studied; however, because the FDA-approved tissue plasminogen activator has low efficacy and side effects, it is necessary to develop safer and more effective treatment candidates. This study aimed at assessing the fibrinolytic and anticoagulation features of a novel serine protease extracted and purified from Diopatra sugokai, a polychaeta that inhabits tidal flats. The purified serine protease was obtained through ammonium sulfate precipitation, affinity chromatography, and ion-exchange chromatography. Its molecular size was identified via SDS-PAGE. To characterize its enzymatic activities, the protease activity at various pH and temperatures, and in the presence of various inhibitors, was measured via azocasein assay. Its fibrinolytic activity and anticoagulant effect were assessed by fibrin zymography, fibrin plate assay, and fibrinogenolytic activity assays. The novel 38 kDa serine protease had strong indirect thrombolytic activity rather than direct activity over broad pH (4-10) and temperature ($37^{\circ}C-70^{\circ}C$) ranges. In addition, the novel serine protease exhibited anticoagulant activity by degrading the ${\alpha}$-, ${\beta}$-, and ${\gamma}$-chains of fibrinogen. In addition, it did not produce cytotoxicity in endothelial cells. Therefore, this newly isolated serine protease is worthy of further investigation as a novel alkaline serine protease for thrombolytic therapy against brain ischemia.

• 대한미세수술학회:학술대회논문집
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• 1994.11a
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• pp.104.1-104.1
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• 1994

• Clinical and Experimental Pediatrics
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• v.46 no.3
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• pp.302-307
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• 2003

The long-term clinical issues in Kawasaki disease are concerned with the coronary artery lesions that result in aneurysmal formation, thrombotic occlusion, progression to ischemic heart disease, and premature atherosclerosis. We here report a 3 month old infant with Kawasaki disease complicated by giant coronary aneurysm with thrombosis. After urokinase(10,000 IU/kg) and heparin(400 IU/kg) were injected for two days as thrombolytic agents, thrombi were successfully dissolved. Even though long-term oral anticoagulation with low-dose aspirin, dipyridamole and coumadin were administered, thrombosis of the left main coronary artery was slowly increased. five years later, coronary angiography showed nearly total occlusion of the left anterior descending artery and collaterals from the right posterior branch and radionuclide scan demonstrated complete reversible perfusion defect of several portions of the left ventricle.

• Tuberculosis and Respiratory Diseases
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• v.66 no.1
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• pp.6-12
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• 2009

Background: The efficacy of several thrombolytic agents for treating massive pulmonary thromboembolism (PTE) has been reported to be similar. However, the difference of the bleeding complications caused by two commonly used thrombolytic agents in PTE patients is not well known. The aim of this study was to compare the therapeutic efficacy and the bleeding complications between urokinase and recombinant tissue-type plasminogen activatior (rt-PA, alteplase) in a Korean medical center. Methods: We retrospectively reviewed the clinical data of the patients who were treated with thrombolytic agents (urokinase and alteplase) because of massive PTE. Results: A total of 40 patients were included: 16 (40%) treated with urokinase and 24 (60%) with alteplase. The patients treated with alteplase showed a shorter duration of using vasopressor agents than did the patients who were given urokinase, but the duration of mechanical ventilation, the length of the ICU stay and the hospital stay were not different between the thrombolytic agents. Five patients treated with urokinase and eight patients treated with alteplase died (p=0.565): One patient in the urokinase group and four patients in the alteplase group died due to pulmonary thromboembolism. Bleeding complications after thrombolysis were observed in 3 patients (7.5%) treated with urokinase and in 11 (27.5%) patients treated with alteplase (p=0.079). Major bleeding complication occurred in 2 patients who were treated with alteplase. Conclusion: Urokinase seems to have fewer bleeding complications with an equivalent efficacy, as compared to alteplase, in Korean patients who suffer with massive pulmonary thromboembolism.

• Journal of Chest Surgery
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• v.34 no.9
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• pp.711-715
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• 2001

Background: Deep venous thrombosis(DVT) is a curable disease when it is appropriately treated in the early stages of onset. The long term follow up of chronic DVT shows poor prognosis with serious complications such as venous valvular insufficiency, venous claudication, venous ulcer and leg swelling. Thrombolytic therapy is a very active treatment that delivers thrombolytic agents via catheter to the target thrombi. The aim of this study is to evaluate the effect of catheter directed thrombolysis using urokinase to acute DVT. Material and Method: We studied 5 patients, who were diagnosed as acute DVT and had no contraindication for selective hemolysis using urokinase. Result: All the patients were successfully recanalized. Total infusion time of urokinase was 2.0$\pm$0.6 days, and the amount was 5.9$\pm$2.45 million IU. In 4 patients, who were diagnosed as May-Therner syndrome, we performed the balloon angioplasty and inserted the stent at the stenotic portion. There were minor complications such as hematuria, hematoma at puncture site, and all of them are self limited. Conclusion: Catheter induced thrombolysis is an effective treatment in acute DVT.

• Archives of Plastic Surgery
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• v.48 no.5
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• pp.511-517
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• 2021

The use of free flaps is an essential and reliable method of reconstruction in complex head and neck defects. Flap failure remains the most feared complication, the most common cause being pedicle thrombosis. Among other measures, thrombolysis is useful when manual thrombectomy has failed to restore flap perfusion, in the setting of late or established thrombosis, or in arterial thrombosis with distal clot propagation. We report a case of pedicle arterial thrombosis with distal clot propagation which occurred during reconstruction of a maxillectomy defect, and was successfully treated with thrombolysis using recombinant tissue plasminogen activator. We also review the literature regarding the use of thrombolysis in free flap surgery, and propose an algorithm for the salvage of free flaps in head and neck reconstruction.

• The Korean Journal of Emergency Medical Services
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• v.17 no.1
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• pp.21-39
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• 2013

Purpose : The purpose of this study is to provide the basic data to improve pre-hospital phase emergency care for acute myocardial infarction (AMI) patients by analyzing AMI patients' clinical characteristics and emergency care situations. Methods : Data were collected through medical records of 385 AMI patients including ambulance records of 107 AMI patients transferred to the emergency medical center for three and a half years. Results : Regarding emergency care for AMI patients in pre-hospital phase, 47% of the care revealed moderate level or higher, and appropriateness of pre-hospital phase emergency care for cardiopulmonary complaints practiced by paramedics showed statistically significant improvement in recent years (p<.001). The time from onset of symptom to ballooning intervention by 119 emergency services was shorter than that in other cases. However, emergency care by paramedic was mainly basic life support. Conclusion : Since prognosis of AMI shows vast differences depending on prompt detection and medical intervention, cooperation between pre-hospital and in-hospital phase is highly required. 119 paramedics should be trained focusing on the accurate assessment and emergency care, and medical direction should be activated. In addition, regulation on 12-lead EKG, cardiac enzyme analysis, use of analgesics and thrombolytic agents should be legally implemented.