• Proceedings of the KSME Conference
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• 2008.11a
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• pp.518-522
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• 2008

Recently, many patients related to heart disease have surgical operation by expanding a blood vessel to treat the angiostenosis. So far most angioplasties have been performed using balloon-dilative stent made of stainless steel. Some researchers are studying the stent made of shape memory alloy (SMA) to operate the angioplasty more easily. and there are several papers which introduce the angioplasty using SMA. However, most of the analysis models for stents are constructed using solid elements. So much computing time is required to solve the analysis model. In this study, we suggest the SMA stent model using 1D truss element which is much faster than stent model using 3D solid element. To represent non-linear behavior of SMA, we apply 1D SMA constitutive equation of Lagoudas'. Pseudo-elastic behavior of stent structures is presented as a numerical example.

• Childhood Kidney Diseases
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• v.27 no.2
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• pp.117-120
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• 2023

Here, we present the case of a 2-month-old male infant with hyponatremic hypertensive syndrome resulting from stenosis of the right proximal and mid-renal arteries. The patient exhibited nephrotic-range proteinuria, low serum albumin, increased serum creatinine, and elevated renin and aldosterone levels. Doppler ultrasonography and computed tomography angiography revealed decreased vascular flow in the small right renal artery. Following a successful percutaneous balloon angioplasty, the patient experienced a decrease in blood pressure and normalization of serum electrolyte levels within a few days. However, it took 3 months for the proteinuria to resolve completely. This case is significant as it represents the first reported instance of a neonate presenting with clinical features resembling congenital nephrotic syndrome caused by renal artery stenosis that was successfully treated with percutaneous renal angioplasty.

• Journal of Chest Surgery
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• v.23 no.2
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• pp.402-406
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• 1990

Recently we have experienced a case of Takayasu’s arteritis involving both common carotid artery, left subclavian artery, left renal artery, and the right pulmonary artery. The patients was 27 year-old female and she was admitted because of neck pain, dizziness and palpitation. Renal artery angioplasty with Griintzig balloon catheter was performed with successful result. And then bypass graft surgery using bifurcated Gore- Text graft was performed with satisfactory result.

• Journal of Chest Surgery
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• v.36 no.4
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• pp.255-260
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• 2003

Background: Stenosis of the left pulmonary artery (LPA) after repair of tetralogy of Fallot (TOF) is troublesome. A new technique of LPA angioplasty using an autologous MPA flap was performed in patients with TOF Material and Method: From October 1998 to January 2001, 24 patients (median age; 10 months, range; 4 to 145 months) underwent total correction of TOF with LPA angioplasty using the autologous MPA flap. Five patients underwent pulmonary angioplasty without any patch over the MPA and LPA. The patches were required to enlarge only the MPA in 4 patients, and transannular RVOT widening was performed in 15. Result: There were no operative or late deaths. During follow-up (range: 6~42 months), reoperation for LPA stenosis was not required in any patients, but balloon angioplasty for branch pulmonary artery stenosis was performed in 3 patients. Echocardiography and CT angiography at the recent follow-up showed an obtuse angle between the MPA and LPA. Conclusion: Although further follow-up is needed, the angioplasty using the autologous MPA flap can be easily performed, avoiding patch-related complications, and allowing growth of the MPA flap. This angioplasty technique creates a more natural and obtuse angle between the MPA and LPA, which can minimize kinking of the LPA, especially in the patients who underwent transannular patch widening.

• Korean Journal of Plant Resources
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• v.26 no.6
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• pp.678-685
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• 2013

The objective of this study was to examine the effect of 7 traditional Korean formulations (7TKFs) on intimal thickening of rat carotid artery injured by balloon catheter in vivo and on the proliferation of human smooth muscle cells (HASMCs) and secretion of matrix metalloproteinase-2 (MMP-2) in vitro. 7TKFs (400 mg/kg) were administered orally for 4 weeks from the day of balloon injury in the rats. HASMC proliferation was assessed by 3-(4,5-dimethylthiazol-2)-2,5-diphenyltetrazolium bromide (MTT) assay while enzymatic action of MMP-2 was carried out by gelatin zymography. Among 7TKFs, Samhwang-sasim-tang (SST), Banha-sasim-tang (BST) and Kegi-honghwa-tang (KHT) significantly reduced the intimal thickening by suppressing HASMC proliferation and MMP-2 expression in both extracellular and intracellular levels. Thus, the results suggest that SST, BST and KHT can be considered as a therapeutic value in the prevention of atherosclerosis because restenosis after PTCA (percutaneous transluminal coronary angioplasty) is supposed to be 'accelerated atherosclerosis'.

• Health Policy and Management
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• v.25 no.1
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• pp.3-10
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• 2015

Background: Previous studies showed differences in healthcare utilization among insurance types. This study aimed to analyze the difference in healthcare utilization for percutaneous transluminal coronary angioplasty inpatients by insurance types after controlling factors affecting healthcare utilization using propensity score matching (PSM). Methods: The 2011 national inpatient sample based on health insurance claims data was used for analysis. PSM was used to control factors influencing healthcare utilization except insurance types. Length of stay and total charges were used as healthcare utilization variables. Patients were divided into National Health Insurance (NHI) and Medical Aid (MA) patients. Factors representing inpatients (gender, age, admission sources, and Elixhauser comorbidity index) and hospitals (number of doctors, number of beds, and location of hospitals) were used as covariates in PSM. Results: Tertiary hospitals didn't show significant difference in length of stay and total charges after PSM between two insurance types. However, MA patients showed significantly longer length of stay than that of NHI patients after PSM in general hospitals. Multivariate regression analysis provided that admission sources, Elixhauser comorbidity index, insurance types, number of doctors, and location of hospitals (province) had significant influences on the length of stay in general hospitals. Conclusion: Study results provided evidences that healthcare utilization was differed by insurance types in general hospitals. Health policy makers will need to prepare interventions to influence the healthcare utilization differences between insurance types.

• Journal of Chest Surgery
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• v.36 no.3
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• pp.202-205
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• 2003

Deep vein thrombosis (DVT) is a common disease. However, May-Thurner syndrome, which is the cause of DVT, is an uncommon processes in which there is an impaired venous return due to compression of the left iliac vein by the overlying right common artery. This condition results in a left iliofemoral deep thrombosis and severe leg edema. It is, therefore, called iliac compression syndrome. Catheter-directed thrombolytic therapy of acute extensive iliofemoral DVT and balloon angioplasty with venous stenting are recommended. Two cases with history of left leg swelling are diagnosed as May-Thurner syndrome, which was demonstrated by venography. We successfully treated the patients with thrombolysis, balloon angioplasty, and stent insertion at the site of common iliac vein compression. Therefore, we report the cases with overall review of the literature.

• Journal of Korean Neurosurgical Society
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• v.64 no.2
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• pp.198-206
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• 2021

Objective : The low-profile Neuroform Atlas stent can be deployed directly without an exchange maneuver by navigating into the Gateway balloon. This retrospective study assessed the safety and efficacy of Neuroform Atlas stenting as a rescue treatment after failure of mechanical thrombetomy (MT) for large artery occlusion. Methods : Between June 2018 and December 2019, a total of 31 patients underwent Neuroform Atlas stenting with prior Gateway balloon angioplasty after failure of conventional MT caused by residual intracranial atherosclerotic stenosis (ICAS). Primary outcomes were successful recanalization and patency of the vessel 24 hours after intervention. Secondary outcomes were vessel patency after 14 days and 3-month modified Rankin Scale. Peri-procedural complications, intracerebral hemorrhage (ICH), and 3-month mortality were reviewed. Results : With a 100% of successful recanalization, median value of stenosis was reduced from 79.0% to 23.5%. Twenty-eight patients (90.3%) showed tolerable vessel patency after 14 days. New infarctions occurred in three patients (9.7%) over a period of 14 days; two patient (6.5%) underwent stent occlusion at 24 hours, and the other patient (3.2%) with delayed stent occlusion had a non-symptomatic dot infarct. There were no peri-procedural complications. Two patients (6.5%) developed an ICH immediately after the procedure with one of them is symptomatic. Conclusion : Neuroform Atlas stenting seems to be an effective and safe rescue treatment modality for failed MT with residual ICAS, by its high successful recanalization rate with tolerable patency, and low peri-procedural complication rate. Further multicenter and randomized controlled trials are needed to confirm our findings.

• Journal of Korean Neurosurgical Society
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• v.29 no.8
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• pp.1113-1120
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• 2000

Objectives : Despite advance in the surgical treatment of the intracranial aneurysm, we have to be surgical complication. The aim of this report is to evaluate the complication and its management in intracranial aneurysm operation. Methods : We reviewed our exprience with interesting cases of surgical complication of intracranial aneurysm : 1) rebleeding, 2) intra-operative premature rupture, 3) missed aneurysm in angiography, 4) vasospasm. Results : The risk of rebleeding was not related to the patients' initial comdition, but all other intracranial complications occurred significantly more often in patients graded poor compared with patients in good clinical condition. Rebleeding before early surgery remains as major cause of unfavorable outcome. The causes of intraoperative premature ruptures were as follows : 1) dural opening and arachnoid opening(8.3%), 2) hematoma removal(12.5%), 3) brain retraction(16.7%) 4) aneurysm dissection(62.5%). The double suction technique and primary hemostasis using a small piece of cotton or temporary clip resulted in good outcome even in cases with premature rupture. The incidence of missed aneurysm in angiography occurred in 10%. The causes were as thrombosed aneurysm, vasospasm on feeder artery. The most common missed aneurysm is also the most common aneurysm(anterior communicating artery aneurysm). The repeated angiography were documented in missed aneurysm. Balloon angioplasty is superior topapaverine for treatment of proximal vessel vasospasm by viture of a more sustained effect on the vessel. Papaverine can be useful as an adjunct to ballon angioplasty and also for the treatment of distal vessels that are not accessible for ballon angioplasty. Conclusion : The minimization of the complications and active treatment can reduced the mortality and morbidity of ruptured aneurysm patients.

• 대한핵의학회:학술대회논문집
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• 1999.05a
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• pp.205-208
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• 1999

Percutaneous Transluminal Coronary Angioplasty (PTCA) remains limited by restenosis that occurs in 30 to 50% of patients with coronary artery disease. During the last decade, numerous agents have been used to prevent restenosis. Despite positive results in animal models, no pharmacological therapy has been found to significantly decrease the risk of restenosis in humans. These discrepancies between animal models and clinical situation were probably related to an incomplete understanding of the mechanism of restenosis. Neointimal thickening occurs in response to experimental arterial injury with a balloon catheter. Neointimal formation involves different steps: smooth muscle cell activation, proliferation and migration, and the production of extracellular matrix. The factors that control neointimal hyperplasia include growth factors, humoral factors and mechanical factors. Arterial remodeling also plays a major role in the restenosis process. Studies performed in animal and human subjects have established the potentials for "constrictive remodeling" to reduce the post-angioplasty vessel area, thereby indirectly narrowing the vessel lumen and thus contributing to restenosis. The reduction of restenosis rate in patients with intracoronary stent implantation has been attributed to the preventive effect of stent itself for this negative remodeling. In addition to these mochanisms for restenosis, intraluminal or intra-plaque thrombus formation, reendothelialization and apoptosis theories have been introduced and confirmed at least in part.