• International Journal of Vascular Biomedical Engineering
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• 제4권2호
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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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• 제46권3호
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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.

• 대한의용생체공학회:의공학회지
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• 제26권3호
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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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• 제28권2호
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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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• 대한미세수술학회 1994년도 제14차 학술대회
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• pp.104.1-104.1
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• 1994

• Clinical and Experimental Pediatrics
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• 제46권3호
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• pp.302-307
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• 2003

환아는 3개월된 영아로 발병 10일째에 본원에 내원하여 초기에 적절한 진단과 치료를 받지 못했으며 발병 2주에 시행한 심초음파상 거대 관상동맥류를 보였다. 이에 정맥용 면역글로불린 투여와 aspirin과 dipyridamole로 치료 중 발병 24일째 혈전증이 동반되어 urokinase와 heparin의 IV 투여를 통한 혈전용해 치료로 혈전을 완전히 제거할 수 있었다. 이후 5년간 aspirin, dipyridamole, coumadin을 투여하면서 심전도와 심초음파검사를 반복하며 외래 추적 관찰 중 점차 좌측관상동맥내 혈전이 증가하고 내경이 점차 좁아지는 소견과 함께 협착이 의심되었다. 발병 5년 후 시행한 관상동맥 혈관조영술상 관상동맥 좌측 전하지가 완전 폐색되고 우측관상동맥으로부터 발달한 측부순환에서 혈류를 공급받고 있었고, 핵의학 검사상 좌심실의 전벽과 중격, 일부 외벽에 완전 가역적 관류 결손을 보였던 가와사끼병 환아 1례를 경험하여 보고한다.

• Tuberculosis and Respiratory Diseases
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• 제66권1호
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• pp.6-12
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• 2009

연구배경: 폐혈전색전증 환자에서 혈전용해제의 효과는 차이가 없는 것으로 보고되어 있으나 출혈 등의 부작용에 대해서는 잘 알려져 있지 않다. 본 연구는 한 병원에서 중증 폐혈전색전증환자들에 사용한 alteplase와 urokinase의 치료효과 및 출혈 유발 정도를 비교하였다. 방법: 2000년 1월부터 2008년 7월까지 대상 환자 40명을 urokinase군(16명)과 alteplase군(24명)으로 나누어 의무기록을 후향적으로 분석하였다. 결과: 혈전용해제 사용한 이유는 혈역학적 불안정 23명, 중증 우심실부전 7명 그리고 헤파린 사용에도 불구하고 진행하는 저산소증 10명이었다. 두 군간 나이, APACHE II, SOFA score, 혈전용해제에서 유의한 차이는 없었다. 혈전용해제를 사용 후 승압제의 사용기간에서 aletplase군이 urokinase군보다 더 짧았으나, 인공호흡기 사용 기간과 중환자실 입원기간에서는 양 군간 유의한 차이가 없었다. 입원기간 동안 사망한 환자수는 13명(30%)으로 urokinase와 alteplase군 5명, 8명으로 유의한 차이는 없었고, 폐혈전색전증과 연관된 사망한 환자수에서도 urokinase와 alteplase군에서 1명, 4명으로 유의한 차이는 없었다. 혈전용해제 사용 후 수술적 치료가 필요한 환자 수도 urokinase군 2명, alteplase군 1명으로 차이가 없었다. 혈전용해제 사용 후 발생한 출혈은 14명(35%)에서 관찰되었고 urokinase군 3명(7.5%), alteplase군 11명(27.5%)으로 urokinase군에서 적은 경향을 보였다. 중증 출혈은 2명으로 모두 alteplase군에서 발생하였으며 1명은 뇌출혈로 사망하였다. 결론: 중증 폐색전혈전증환자에서 urokinase 사용은 alteplase에 비하여 치료효과는 차이가 없으면서 출혈의 위험은 낮을 것으로 사료된다.

• Journal of Chest Surgery
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• 제34권9호
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• pp.711-715
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• 2001

배경: 심부정맥 혈전증인 증세발현 초기에 적절히 치료하면 완치될 수 있는 질환이다. 만성 심부정맥 혈전증을 장기 추적해 보면 그 결과가 정맥판막 폐쇄부전증, 정맥성 파행, 울혈성 궤양 및 하지 부종 등의 심각한 합병증을 유발한다는 것을 알 수 있다. 혈전 용해술은 용해제를 직접 원하는 혈전 부위에 주입하는 적극적인 치료방법이다. 이 연구의 목적은 유로키나제를 카테터를 통하여 주입하는 방법으로 급성 심부정맥 혈전증을 치료하여 그 효과를 확인하고자 하였다. 대상 및 방법: 급성 심부정맥 혈전증으로 진단받고, 선택적 혈전 용해술에 금기 사항에 없는 5명의 환자를 대상으로 하였다. 결과: 임상적으로 대부분의 혈전을 녹이는데 성공하였다. 총 혈전용해제 투여시간을 평균 2.0$\pm$0.6일 이었고, 유로키나제 사용량은 평균 590만$\pm$245만 IU였다. May-Therner 증후군으로 진단한 4명의 환자에게 총 5개의 스텐트를 삽입하였다. 시술 후 혈뇨가 2예, 천자부위의 혈종이 1예 등이 있었으나 모두 자연 소실되었다. 결론: 급성 심부정맥 혈전증에서 카테터를 이용한 혈전 용해술은 매우 유용한 치료방법이다.

• Archives of Plastic Surgery
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• 제48권5호
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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.

• 한국응급구조학회지
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• 제17권1호
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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.