Clinical characteristics and prognosis of Korean patients with ventricular tachycardia

Background: Although the determination of etiology is crucial for the management of ventricular tachycardia (VT), there have been few studies on the epidemiology and clinical characteristics of patients with ventricular tachycardia in Korea. Previous studies on Western populations have shown that ischemic VT is the most common type arrhythmia; however, the incidence of ischemic heart disease in Korea is lower than in Western culture. The purpose of this study was to determine the clinical characteristics and prognosis of Korean patients with VT. Methods: From January 1999 to December 2002 patients who were diagnosed with VT by ECG or confirmed by electrophysiological studies were enrolled. Hospital records were reviewed for the clinical characteristics which included: demographic features, underlying disease, clinical presentation, ECG features and prognosis in 136 patients who visited our emergency room or out patient clinic. Results: There were 100 men and 36 women (mean age 51.517.6). The most common presenting symptom was palpitation (56.6%), which was followed by chest pain and syncope. The most common type of VT was idiopathic VT (54.4%); ischemic VT was found in 29 cases (21.3%) and dilated or hypertrophic cardiomyopathy in 16 cases (11.8%). For all types of VT, the idiopathic VT showed the best prognosis and cardiac function (p<0.05). RFCA (Radiofrequency catheter ablation) was the best treatment option for treatment of idiopathic VT (p<0.05). Conclusions: These findings suggest that idiopathic VT may be the most common type of VT in Korean patients; it usually originates form either the right ventricular outflow tract (RVOT) or the LV. The response to treatment and prognosis was poor in VT patients who had underlying heart disease; however, the prognosis was excellent for those with idiopathic VTope

Endovascular Drug-Coated Stenting of Basilar Artery Stenosis: A Case Report and Literature Review

Patients with a symptomatic basilar artery stenosis have a poor prognosis and limited therapeutic options. Despite the best medical efforts, there is still a high incidence of stroke. A surgical bypass is technically demanding with a high mortality and morbidity rate. Percutaneous angioplasty still carries a risk of procedure related complication and restenosis. Stenting has been shown to improve the safety and durability of angioplasty in the coronary and peripheral arteries. Recently, stenting of the intracranial arteries has been attempted by some investigators with newer and more trackable stents. We report a case of a basilar artery stenosis that was successfully treated using a drug-coated stent.ope

Alagebrium chloride, a novel advanced glycation end-product cross linkage breaker, inhibits neointimal proliferation in a diabetic rat carotid balloon injury model.

BACKGROUND AND OBJECTIVES: Vascular perturbation induced by advanced glycation end-products (AGEs) leads to progression of atherosclerosis, plaque instability, and vascular inflammation, which results in a higher risk of neointimal proliferation. Here we investigated the inhibitory effect of alagebrium chloride (ALT-711), a breaker of AGE-based cross links, on neointimal proliferation in a carotid artery balloon injury model in diabetic rats induced by streptozotocin (STZ). MATERIALS AND METHODS: Rat aortic vascular smooth muscle cells (RASMCs) were treated with 1-100 µM of alagebrium added 24 hours before the addition of AGEs. This in vivo study was done using 8-week-old male rats that were injected intraperitoneally with 80 mg/kg STZ. Sixteen weeks later, the diabetic rats were treated with 10 mg/kg alagebrium for 4 weeks, after which carotid artery balloon injury was induced. After 4 weeks, the animals were sacrificed for histological analysis. RESULTS: Proliferation of RASMCs was significantly inhibited in alagebrium-treated cells. Alagebrium dose-dependently inhibited AGE-mediated formation of reactive oxygen species (ROS), extracellular signal-regulated kinase phosphorylation, and cyclooxygenase-2 expression. The cellular mechanisms of AGE-induced connective tissue and extracellular matrix expression were decreased in the alagebrium-treated group. This in vivo study shows that expression of AGE receptors and neointima hyperplasia are significantly suppressed in balloon-injured rats treated with alagebrium. CONCLUSION: Alagebrium treatment in diabetic rats significantly inhibits neointimal hyperplasia after carotid balloon injury due to its inhibition of intracellular ROS synthesis, which results in inhibition of RASMCs proliferationope

The Prognostic Significance of ST Segment Depression Score in Acute Non ST Elevation Myocardial Infarction

Background and Objectives：A significant ST segment depression is known to be an independent risk factor for acute coronary syndrome (ACS). Defining high risk groups in non ST elevation myocardial infarction (NSTEMI) is especially important due the poor long term prognosis of these patients. The purpose of this study was to determine the prognostic significance of the degree of ST depression on admission, as determined by a novel ST depression scoring system. Subjects and Methods：68 patients, admitted to Yonsei Cardiovascular Hospital between Jan 2001 and Aug 2002, and diagnosed with acute non ST elevation myocardial infarction were included in this study. Analysis of the initial ECG on admission was retrospectively performed. Results：ST depression scores ≥1 and <1 were present in 36 (Group I) and 32 (Group II) patients, respectively. The rate of multivessel disease was significantly higher in group I than II (76.7 vs. 50%, p=0.032), the use of glycoprotein IIb/IIIa inhibitors was more frequent in group I than II (25 vs. 6.3%, p=0.041) and the left ventricular ejection fraction was significantly lower in group I than II (44.6±14.5 vs. 54.5±11.6%, p<0.05). The one-year survival rates were 68.9 and 93.7% for Groups I and II, respectively; p=0.0095), with Group I having a significantly higher early in-hospital mortality rate compared to group II.( 27.8 vs. 3.1%, p=0.0058) The event free survival rate in group I was lower than that in group II (55 vs. 90.6%, p=0.001). Conclusion：The ST depression score may be useful as an objective prognostic factor in acute NSTEMI, which may be especially useful for prediction of the early in hospital prognosis.ope

Right-to-Left Shunting through a Patent Foramen Ovale as a Cause of Hypoxemia in a Patient with Acute Right Ventricular Infarction Diagnosed by Contrast Echocardiography

Right ventricular (RV) infarction is a well-recognized complication of acute inferior myocardial infarction. Right-to-Left shunt through a patent foramen ovale (PFO) is an unusual complication of acute RV myocardial infarction that can result in the development of severe hypoxemia. However, the diagnosis may not be easy without high index of suspicion and echocardiography combined with an echocardiographic contrast (agitated saline) is useful diagnostic imaging modality in this regard. We report a case of acute inferior myocardial infarction and RV infarction associated with unexplained hypoxemia. Contrast echocardiography detected a significant right to left shunt through patent foramen ovale, which considered as a cause of hypoxemia in this patient.ope

당뇨 백서 모델의 경동맥 손상후 신생 내막 증식에 대한 A

Dept. of Medicine/박사[한글] 최근 보고에 의하면 당뇨에서의 지속되는 고혈당증은 AGEs의 생성을 야기하며 그것들의 축적은 죽상동맥경화증과 플라크 불안정의 진행을 이끄는 혈관벽 기억과 손상을 유도한다. 게다가, 동맥협착증 동물 실험에서 AGEs의 신생혈관내막 형성 역할이 보고 되고 있다. 콜라겐과 같은 단백질 교차결합 형성에 관계하는 AGE는 동맥들을 경직시킬 뿐만 아니라 세포내막 형성 상승과 신생혈관 내막 증식의 높은 위험성을 가진 혈관 염증을 증가시키기도 한다. In vitro 연구에서는 AGE 처리된 RASMC의 증식에서 alagebrium의 농도 의존적인 억제 효과를 나타냈다. 이는 활성산소종 형성에 관계된 AGE에 대해 alagebrium의 의미 있는 농도 의존성 억제가 나타났다. 이는 또한 pMAPK 형성의 농도 의존적 억제와 연관됐다. 이러한 세포의 기작은 RASMC에서AGE가 유도된 CTGF와 세포 외 기질 발현에 영향을 주는 alagebrium과 연관되었다. In vivo 연구에서는 플라시보와 비교하여 alagebrium을 처리한 풍선도관으로 손상된 쥐에서 신생 혈관내막 과형성의 억제가 일어났다. 결과적으로, alagebrium은 혈관 평활근 세포 증식의 억제를 일으키는 세포 내 활성산소종을 제어하기 때문에 경동맥 풍선도관 손상 후 신생 혈관내막 과형성을 억제하였다. 신생혈관 형성에 영향을 주는 alagebrium의 억제 효과는 세포 외 기질 형성을 감소시키는데 연관되어 있을 것이다. [영문] Recent report has shown that longstanding hyperglycemia in diabetes leads to generation of AGEs (advanced glycation end products) and their accumulation induce vessel wall memory and vascular perturbation that lead to progression of atherosclerosis, plaque instability. Moreover, AGEs are reported to have a role in neointimal formation in animal experiment of arterial stenosis. AGE mediated cross link formation of proteins such as collagen will not only result in stiffening of the arteries, but will result in increased extracellular matrix formation and increased vascular inflammation resulting in higher risk of neointimal proliferation. The in vitro study revealed a dose-dependently inhibitory effect of Alagebrium on AGE stimulated proliferation of RASMC. There was a significant dose dependent inhibition of AGE mediated reactive oxygen species formation by alagebrium. This was associated with a dose dependent inhibition of pMAPK formation as well. This cellular mechanism was involved in the regulatory effect of alagebrium on AGE-induced CTGF and ECM expression in RASMC. The in vivo study revealed a significant inhibition of neointima hyperplasia in ballooned injured rats treated with Alagebrium compared to placebo. In conclusion, alagebrium inhibits neointimal hyperplasia after carotid balloon injury because it blocks the intracellular ROS synthesis resulting in inhibition of vascular smooth muscle cell proliferation. The inhibitory effect of alagebrium on neointimal formation may be also mediated by reduction of extracellular matrix production.ope

Clinical features and prognosis of ventricular tachycardia in Korean patients

의학과/석사[한글] 심실빈맥(Ventricular tachycardia: VT)은 심실에서 기원하며 정상 전도로를 경유하지 않는 연속된 3회 이상의 심실박동으로 정의하며 그의 임상양상에 따라 지속성과 비지속성, 단일형과 다형 등으로 분류할 수 있다. 심실 빈맥의 원인 질환으로 허혈성 심질환이 가장 흔하다고 보고되고 있으나 우리나라의 경우 허혈성 심질환에 의한 심실 빈맥의 빈도나 임상양상 및 예후에 대하여 국내 보고가 미흡한 상태였다. 따라서 본 연구를 통해 우리나라에서 발생한 심실 빈맥의 임상적 특징과 예후에 대해 알아보고자 하였다. 대상 환자 136명중 남자는 100명(73.5%), 여자는 36명(26.5%) 으로 남녀 비는 2.76:1였다. 환자의 발작 시 증상 중 가장 많이 호소 하였던 것은 심계 항진(50.8%)이었으며 흉통(17.6%), 졸도가 15예(11.0%), 호흡곤란 7예(5.1%), 심장 돌연사 7예(5.1%)였으며 무증상인 경우가 2예(1.5%), 기타 다른 증상이 4예(2.9%)였다. 심실 빈맥의 발생에 특별한 유발 인자가 없었던 경우가 제일 많았으며(58.1%), 물리적인 활동(45예:33.1%), 감정적인 스트레스 (10예:7.4%)가 유발인자로 관찰되었다. 심전도상의 특징을 살펴보면 기저 심박수는 74.8±17.5회, QRS폭은 101.1±18.5ms였으며 전기축은 정상축이 가장 많았으며 V1 유도의 QRS모양으로 분류해 보면 우각 차단형이 54예(39.7%), 좌각 차단형이 44예(32.4%), 다형 심실 빈맥이 15예(11.0%)였으며 V1유도가 기록되지 않았던 경우가 23예(16.9%)있었다. 심실 빈맥의 원인 질환으로는 특발성 심실 빈맥이 74예(54.4%)로 가장 많았으며 허혈성 심질환이 29예(21.3%)로 그 다음을 이었다. 특발성 심근병증이 16예(11.8%)였으며 심판막증이 6예(4.4%)있었고 그 밖에도 선천성 심질환(3예), Long QT 증후군(4예), Brugada 증후군 (4예) 있었다. 추적 관찰되었던 119예 중에서 재발되었던 환자는 31예(22.8%) 였으며 사망한 환자는 12예(10.1%) 였다. 추적 관찰에서 재발 및 사망 여부가 확인되지 않은 환자는 17명(13.9%)였다. 재발하기까지의 기간이나 사망률로 환자의 예후를 판별하였는데, 여타 질환에 비해 특발성 심실 빈맥의 경우가 통계적으로 유의하게 좋은 예후를 보여 주었으며 허혈성 심질환인 경우가 가장 좋치 못한 결과를 보여 주었다.(P<0.05) 특발성 심실 빈맥의 치료법 중 전극 도자 절제술(RFA)가 가장 좋은 예후를 보여 주었으며 득발성 심실 빈맥의 경우 사망환자는 없었다. (P<0.05) 이상의 결과로 볼 때 국내 심실 빈맥의 환자는 서구와는 달리 특발성인 경우가 가장 많았고 특발성 심실 빈맥의 경우가 다른 심실 빈맥에 비하여 예후가 가장 좋았으며 특발성 심실 빈맥의 치료 방법 중 전극 도자 절제술(RFA)의 효과가 가장 좋았다. [영문]There have been few studies on the epidemiology and clinical characteristics of ventricular tachycardia(VT) in Korea. Although their determination data is crucial in the management of VT The purpose of this study was to determine the clinical characteristics and prognosis of VT. Materials and methods : From Jan. 1999 to Dec. 2002, 158 patients, who were diagnosised as VT by ECG recording during the VT and confirmed by electrophysiological studies in some case are enrolled. Hospital records were reviewed as to clinical characteristics which included demographic features, underlying disease, and clinical presentation in 136 patients who visited our emergency room or the out patient clinic and had VT as the primary medical problem Results : There is 100 men and 36 women (mean age 51.45±17.6). The most common presenting symptom was palpitaion(56.6%), which was followed by chest pain, syncope. and most common type of VT is idiopathic VT in Korea(54.4%). Ischemic VT is 29 cases(21.3%) and dilated and hypertropic cardiomyopathy are 16 case(11.8%) In several type of VT, idiopathic VT is best prognosis and cardiac function(p < 0.05). RFA is best treatment option in idiopathic VT(p < 0.05). Conclusion : These findings suggest that idiopathic VT may be the most common type of VT in Korean patients and usually originates form either the RVOT or the LV. The response to medical therapy is poor in VT patients who have an underlying heart disease but excellent in those who have idiopathic VT.ope

Relationship between global warming and wild fire.

산림청 자료에 의하면 전국 연평균 산불 건수는 1980년대에 179건, 1990년대에 402건, 2000년대에 491건으로 2000년대가 1980년대에 비래 2.7배 증가하였다. 우리나라에서 대부분의 산불은 인간의 부주의에 의해서 발생하지만 지구온난화로 인한 봄철의 온도 상승과 습도의 감소는 대기를 더욱 건조하게 하여 사소한 발화 요인에도 산불이 발생할 수 있음을 의미한다.2

PERFORMANCE OF TRANSACTION BACKOUT STRATEGIES FOR NETWORK PARTITIONS

분산 데이타베이스 시스템에서 분할 고장이 발생했을 때 트랜잭션을 수행시키는 두가지 방법(비관적인 방법과 낙관적인 방법) 중 낙관적인 방법을 사용할 경우 네트워크에 합병될 때 데이타베이스의 일관성을 유지시켜 주기 위해 불가피하게 충돌이 발생한 일부 트랜잭션을 철회시켜야 한다. 그런데 기존의 Davidson의 알고리즘은 단계 1에서 2-사이클만 제거시키고 단계 2에서 남은 긴 사이클을 제거시킨다. 이때 단계 1에서 2-사이클만 고려함으로써 불필요하게 철회되는 트랜잭션이 존재할 수 있다. 본 논문에서는 단계 1에서 2-사이클과 특별한 형태의 긴 사이클인 물결 사이클을 함께 고려할 수 있는 알고리즘을 설계하고 기존의 Davidson의 알고리즘과 철회되는 트랜잭션의 수 및 수행시간을 척도로 성능 평가를 하였다. 결과는 read/write 비율이 낮은 부분인 높은 충돌의 경우에 두 알고리즘은 거의 차이가 없으나 read/write 비율이 높은 부분인 낮은 충돌의 경우 제안된 알고리즘은 철회되는 트랜잭션의 수가 줄어들고 수행시간도 줄었다

Analysis of meteorological elements for the optimum use of solar energy

우리나라에서 태양에너지 최적 활용이 좋은 곳을 알기위하여 1988~2007년을 평균한 월별, 계절별, 년별 14개 기상요소를 분석하였으며 이들 요소는 (1) 일사량, (2)일조시간, (3) 강수량, (4) 강수일수, (5) 강수계속시간, (6) 평균기온, (7) 평균 최고기온, (8) 평균 최저기온, (9) 운량, (10) 상대습도, (11) 안개일수, (12) 황사일수, (13) 연무일수, (14) 박무일수이다. 분서위치는 기상청의 일사 관측 22지점(대관령, 춘천, 강릉, 서울, 인천, 원주, 수원, 서산, 청주, 대전, 추풍령, 안동, 포항, 대구, 전주, 광주, 부산, 목포, 흑산도, 제주, 고산, 진주)이다. 분석결과 남쪽 해안지역과 서해안지역의 일사량이 많고 일조시간이 길며 평균기온, 평균 최고기온, 평균 최저기온이 다른 지역에 비해 높다. 구름의 양과 황사일수는 많으며, 상대습도는 높다.2