• Applied Microscopy
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• 제23권1호
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• pp.139-163
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• 1993

Background: It has been well established and is now no longer a controversial issue that ischemia produces a series of inflammatory reactions and the ischemic myocardium cannot survive without adequate restoration of coronary flow, ie, reperfusion. Nevertheless, controversies that intravascular pluggings (IVP) by polymorphonuclear leukocytes (PMNs) or platelets may cause contractile dysfunction in ischemia and even in repefusion still remain. Accordingly, we attempted to examine the intravascular plug fomation as well as the ultrastructural changes in myocytes and microvessels and to determine the relation among them. Methods: 1) Human (n= 10, 39-63 years of age; 3 females and 7 males): left ventricular myocardium (LVM) was biopsied from chronic ischemic heart disease patient during bypass surgery. 2) Calf (Holstein-Friesian species, n=4): Circumflex branch of the left coronary artery (LCx) was occluded (ischemia) for 45 minutes and recanalized (reperfusion) for 3 and 6 hours, respectively and LVMs were biopsied after occlusion and recanalization, respectiverly. 3) Rat (Sprague-Dawley species, n=20): Left coronary artery (LCA) was occluded for 20 minutes and recanalized for an hour as the method described by Selye et al., (1960) and hearts were removed after occlusion and recanalization, respectively. 4) Pig (landrace type, n=7): Anterior ascending branch of the left coronary artery (LAD) was coccluded for 45 minutes and recanalized for 2 hours and LVMs were biopsied after occlusion and recanalization, repectively. All of the LVMs were routinely prepared for transmissiom electron microscopy. Rseults: In human, most of the LVM showed irreversible ultrastructural changes in myocytes and frequent IVPs by PMNs or platelets without any significant correlation with age or sex. In the animal LVM, myocytes showed reversible ultrastructural changes with slight variations in accordance with the species, duration of ischemia and reperfusion or site of biopsy, however, injuries were more severe in the subendocardial myocytes and IVPs by PMNs or platelets were frequently observed. Ultrastructural changes in the myocytes seemed to be gradually improved by recanalization, howerver, IVPs were still observed after recanalization. Conclusion: These results suggest that microvessels are more resistant to ischemic insult than the myocytes themselves and IVP by PMNs and platelets may play an important role to produce ischemic or reperfusion injuries. Thus, it is favorable that angioplasty is preceded by thrombolysis and it is likely that restoration of myocardial function requires relarively long period of time even after recanalization.

• Journal of Chest Surgery
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• 제54권2호
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• pp.117-126
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• 2021

Background: Several factors, such as the degree of target vessel stenosis, are known to be associated with radial artery (RA) graft patency in coronary artery bypass grafting (CABG). There is a lack of data regarding the effect of the RA proximal configuration (aortic anastomosis versus T-anastomosis). This study evaluated the effects of the RA proximal configuration on the patency rate and clinical outcomes after CABG. Methods: We conducted a retrospective study, analyzing 328 patients who had undergone CABG with an RA graft. We divided the patients into 2 groups. The primary endpoint was RA patency and the secondary endpoints were overall mortality and major adverse cardiac and cerebrovascular events (MACCE). We performed a propensity score-matched comparison. Results: Aorta-RA anastomosis was performed in 275 patients, whereas the rest of the 53 patients received T-RA anastomosis. The mean age was 67.3±8.7 years in the T-RA anastomosis group and 63.8±9.5 years in the aorta-RA anastomosis group (p=0.02). The mean follow-up duration was 5.13±3.07 years. Target vessel stenosis ≥70% (hazard ratio [HR], 0.42; 95% confidence interval [CI], 0.20-0.91; p=0.03) and T-RA anastomosis configuration (HR, 2.34; 95% CI, 1.01-5.19; p=0.04) were significantly associated with RA occlusion in the multivariable analysis. However, T-RA anastomosis was not associated with higher risks of overall mortality and MACCE following CABG (p=0.30 and p=0.07 in the matched group, respectively). Conclusion: Aorta-RA anastomosis showed a superior patency rate compared to T-RA anastomosis. However, the RA proximal anastomosis configuration was not associated with mortality or MACCE.

• Journal of Chest Surgery
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• 제34권4호
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• pp.365-367
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• 2001

매우 드물게 발생하지만 대동맥판막수술중에 우관상동맥의 급성폐색은 우심실부전을 일으켜 매우 치명적인 결과를 초래할 수 있다. 심한 대동맥 판막부전증을 가진 67세 여자 환자에서 19 mm Hancock II 조직판막을 이용하여 대동맥판막치환술을 시행한 후 심폐기에서 이탈하는 과정주에 우심실부전이 발견되었으며, 우관상 동맥의 폐색을 의심하여 우측 내흉동맥을 사용하여 관상동맥 우회수술을 시행하였고 이후에 심폐기에서 순조롭게 이탈할 수 있었다. 수술후 9일째 시행한 관상동맥 조영술에서 우관상동맥 근위부에 색전에 의한 폐색을 확인할 수 있었다. 이에 저자들은 우관상동맥의 폐색으로 인한 우심부전증이 우관상동맥우회수술후에 회복된 증례를 보고하고자 한다.

• Journal of Yeungnam Medical Science
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• 제35권2호
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• pp.227-231
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• 2018

Left main coronary artery (LMCA) thrombosis is rare and the cause should be determined. A previously healthy young man presented with severe chest pain and dyspnea. The electrocardiogram showed typical ST-segment elevation myocardial infarction with clinical instability. Emergency coronary angiography revealed complete LMCA occlusion by thrombosis. After reperfusion, the patient was admitted to the cardiac care unit. He was diagnosed with hemolytic anemia and tested positive for antinuclear antibodies. Systemic lupus erythematosus (SLE) and LMCA disease due to systemic thrombosis were diagnosed. Steroids were started and the patient was discharged without complications. We report this rare case of LMCA thrombosis as an initial presentation of SLE.

• Advances in biomechanics and applications
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• 제1권4호
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• pp.279-292
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• 2014

This paper presents some simulations of fluxes and pressures in the coronary network, in the case of very severe coronary disease (several stenoses on the left branches and total occlusion of the right coronary artery). In that case, coronary artery bypass graft surgery is the commonly performed procedure. However, the success of the intervention depends on many factors. Modeling of the coronary circulation is thus important since it can help to understand the influence of all these factors on the coronary haemodynamics. We previously developed an analog electrical model that includes the eventual presence of collateral flows, and can describe the different revascularization strategies (two grafts, three grafts, ...). The aim of the present work is to introduce in our simulations the time-dependence of the coronary microvascular resistances, in order to better represent the effect of the systolic ventricular contraction (which induces an elevation of the resistances because the vessels are squeezed).

• Journal of Chest Surgery
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• 제35권3호
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• pp.231-234
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• 2002

모야모야 병은 혈관 내막의 이형성증으로 인하여 양측 내경동맥의 원위부나 뇌혈관의 근위부 폐쇄와 이로인한 측부 혈관의 발달로 인한 비정상적인 혈관망을 가지는 질환이다. 그러나 모야모야 병이 전신 혈관을 침범하는 질환이라는 보고들이 나오고 있으며, 실제로 신동맥이나 관상동맥을 침범한 모야모야 환자들에 대하여 보고가 되고 있다. 고려대학교 구로병원 흉부외과학 교실에서는 관상동맥을 침범한 모야모야 병 환자 1례를 경험하였다. 환자는 35세 여자로 내원 6개월 전부터 NYHA class ll의 호흡 곤란과 흉통이 있었고, 내월 1개월 전부터는 신체 우측 부위의 감각 이상이 발생되어 내원하였다. 내원하여 시행한 뇌혈관 조영술과 관상동맥 조영술 등의 검사에서 뇌혈관계의 이상을 보이는 모야모야 병과 이로 인한 뇌경색 및 좌측 관상동맥 기시부의 협착으로 인한 협심증을 진단받았으며, 뇌경색에 대하여는 약물 치료를, 협심증에 대하여는 관상동맥 우회술을 시행하였다. 수술 시야에서의 관상동맥 소견은 해부학적 이상 소견이나 전형적인 혈전이나 동맥 경화의 소견 등은 관찰되지 않았고, 전반적으로 부드럽고 혈관 내벽의 비후 소견을 보이는 등 모야모야 병의 병리학적 특성을 보여주어 이 환자의 협심증은 모야모야 병이 관상동맥을 침범하여 발생된 것으로 결론지었다. 따라서 모야모야 병 환자의 경우에는 전신 혈관에 대한 검사 및 치료가 병행되어야 할 것이며, 위와 같은 경험은 아마도 국내의 첫 보고인 것으로 사료된다.

• Clinical and Experimental Pediatrics
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• 제56권2호
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• pp.90-93
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• 2013

Congenital coronary arteriovenous fistulas (CCAFs) are rare coronary artery abnormalities in which blood is shunted into a cardiac chamber or great vessel. If the fistula itself is large and tortuous, it is generally recommended to occlude the fistula to prevent several complications. In approaches of transcatheter occlusion, the transvenous approach is preferred over the transarterial approach. The transvenous approach would enable the cannulation of a relatively larger catheter or sheath without potential damage to the femoral vessels or normal coronary arteries, which can occur in the transarterial approach. The transvenous approach may also minimize the blind pouch after releasing the devices. Herein, we report the success of transvenous proximal closure of a CCAF using an Amplatzer vascular plug (AVP) in a 3-year-old patient with cardiomegaly. Complete occlusion was achieved by a single AVP and thrombus formation of the distal aneurysmal portion of the fistula. We suggest that this strategy of closing the proximal end with a dilated fistula using a single AVP by the transvenous approach may be a good option in treating CCAFs in a young child.

• Nutrition Research and Practice
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• 제8권4호
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• pp.391-397
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• 2014

BACKGROUND/OBJECTIVE: Myocardial cell death due to occlusion of the coronary arteries leads to myocardial infarction, a subset of coronary heart disease (CHD). Dietary fiber is known to be associated with a reduced risk of CHD, the underlying mechanisms of which were suggested to delay the onset of occlusion by ameliorating risk factors. In this study, we tested a hypothesis that a beneficial role of dietary fiber could arise from protection of myocardial cells against ischemic injury, manifested after occlusion of the arteries. MATERIALS/METHODS: Three days after rats were fed apple pectin (AP) (with 10, 40, 100, and 400 mg/kg/day), myocardial ischemic injury was induced by 30 min-ligation of the left anterior descending coronary artery, followed by 3 hr-reperfusion. The area at risk and infarct area were evaluated using Evans blue dye and 2,3,5-triphenyltetrazolium chloride (TTC) staining, respectively. DNA nicks reflecting the extent of myocardial apoptosis were assessed by TUNEL assay. Levels of cleaved caspase-3, Bcl-2, and Bax were assessed by immunohistochemistry. RESULTS: Supplementation of AP (with 100 and 400 mg/kg/day) resulted in significantly attenuated infarct size (IS) (ratio of infarct area to area at risk) by 21.9 and 22.4%, respectively, in the AP-treated group, compared with that in the control group. This attenuation in IS showed correlation with improvement in biomarkers involved in the apoptotic cascades: reduction of apoptotic cells, inhibition of conversion of procaspase-3 to caspase-3, and increase of Bcl-2/Bax ratio, a determinant of cell fate. CONCLUSIONS: The findings indicate that supplementation of AP results in amelioration of myocardial infarction by inhibition of apoptosis. Thus, the current study suggests that intake of dietary fiber reduces the risk of CHD, not only by blocking steps leading to occlusion, but also by protecting against ischemic injury caused by occlusion of the arteries.

• 대한핵의학회지
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• 제27권2호
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• pp.210-217
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• 1993

To compare the myocardial viability in patients suffering from total occlusion of the right coronry artery (RCA) with the angiographic collaterals, intracoronary injection of Thallium-201 (T1-201) was done to 14 coronary artery disease (CAD) patients (pts) with total occlusion of RCA and into four normal subjects for control. All 14 CAD pts had Grade 2 or 3 collateral circulations. There were 14 male and 4 females, and their ages ranged from 31 to 70 years. In nine pts, T1-201 was injected into left main coronary artery (LCA) ($300{\sim}350{\mu}Ci$) to evaluate the myocardial viability of RCA territory through collateral circulations. The remaining five pts received T1-201 into RCA ($200{\sim}250{\mu}Ci$) because two had intraarterial bridging collaterals and three had previous successful PTCA. Planar & SPECT myocardial perfusion images were obtained 30 minutes, and four to five hours after T1-201 injection. Intravenous T1-201 reinjection (six pts) or $^{99m}Tc-MIBI$ (two pts) were also performed in eight CAD pts. Intracoronary myocardial perfusion images were compared with intravenous T1-201 (IV T1-201) images, ECG, and ventriculography. Intracoronary T1-201 images proved to be superior to that of IV T1-201 due to better myocardial to background uptake ratio and more effective in the detection of viable tissue. We also found that perfusion defects were smaller on intracoronary T1-201 images than those on the IV T1-201. All of the 14 CAD pts had either mostly viable myocardium (seven pts) or large area of T1-201 perfusion (seven pts) in RCA territory, however ventriculographic wall motion and ECG did not correlate well with intracoronary myocardial perfusion images. In conclusion, total RCA occlusion patients with well developed collateral circulation had large area of viable myocardial in the corresponding territory.

• Journal of Chest Surgery
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• 제41권3호
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• pp.366-368
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• 2008

관상동맥 우회수술 후 협심증이 재발한 46세 남자 환자로 입원 후 시행한 관상동맥조영술 상에서 과거에 없었던 첫 번째 대각지의 폐쇄가 확인되어 좌측 후측방개흉술을 이용한 관상동맥 우회 재수술을 시행하였다. 우측와위에서 좌측 후측방개흉술을 시행하였고 심폐바이패스 없이 우측 요골 동맥을 이용하여 하행 흉부 대동맥과 대각지 사이에 문합을 시행하였다. 술 후 시행한 다중검출 전산화 단층 촬영을 이용한 관상동맥조영술상에서 문합부위에 이상이 없음을 확인하였다. 대각지에 국한된 병변을 가진 환자에서 좌측 후측방개흉술을 통해 관상동맥 우회 재수술을 시행하여 만족할만한 결과를 얻었기에 보고하는 바이다.