• Journal of Chest Surgery
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• v.44 no.2
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• pp.89-98
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• 2011

Background: Although considerable efforts have been made to improve the graft patency in coronary artery bypass surgery, the role of biomechanical factors remains underrecognized. The aim of this study is to investigate the influences of geometric configurations of the bypass graft on hemodynamic characteristics in relation to anastomosis. Materials and Methods: The Numerical analysis focuses on understanding the flow patterns for different values of inlet and distal diameters and graft angles. The Blood flow field is treated as a two-dimensional incompressible laminar flow. A finite volume method is adopted for discretization of the governing equations. The Carreau model is employed as a constitutive equation for blood. In an attempt to obtain the optimal aorto-coronary bypass conditions, the blood flow characteristics are analyzed using in vitro models of the end-to-side anastomotic angles of $45^{\circ}$, $60^{\circ}$ and $90^{\circ}$. To find the optimal graft configurations, the mass flow rates at the outlets of the four models are compared quantitatively. Results: This study finds that Model 3, whose bypass diameter is the same as the inlet diameter of the stenosed coronary artery, delivers the largest amount of blood and the least pressure drop along the arteries. Conclusion: Biomechanical factors are speculated to contribute to the graft patency in coronary artery bypass grafting.

• Journal of Chest Surgery
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• v.30 no.7
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• pp.724-728
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• 1997

We experienced a case of thoracic aortic aneurysm combined with coronary artery disease. A 68-year-old man complained of anginal pain in the left anterior chest and nonspecific pain in the posterior chest. The aneurysm was extending from left subclavian artery to the diaphragm and sign of impending rupture was noted in the chest CT. Coronary angiograms r vealed significant obstruction of left circumflex coronary artery(>95%) and left anterior descending artery(>50%). Exposure was obtained through the left posterolateral thoracotomy incision in the 4th intercostal space and then partial femoro-femoral cardiopulmonary bypass was established. After aortic cross clamping, the aneurysmal sac was opened and repaired with interposition of 26 mm Hemashield graft. Under the beating heart with femoro-femoral cardiopulmonary bypass, aorto-left circumflex coronary bypass with autogenous saphenous vein used as conduit was performed. Postoperatively multiple cerebral infarction ensued due to intraoperative hypovolemic shock and hypoxic brain damage during cardiopulmonary bypass. Currently, the patient's mental status is drowsy and in an improving state.

• Journal of Chest Surgery
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• v.20 no.2
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• pp.384-392
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• 1987

The occlusive coronary artery disease presents a potential threat to a significant population in the United State. According to many case reports, the increasing incidence of coronary artery disease due to atherosclerosis is noted in Korean, recently. We experienced one case of coronary artery disease. He was a 68 year old male who had been suffered from hypertension since 1 5 years ago, and had intermittent conservative treatment at local clinic. He had been afflicted with severe chest pain on exertion, but this symptom was relieved on rest. Pre-operative EKG finding revealed no any other ischemic sign. Significant S-T segment depression was noted at lead II, aVF, V3, V4, and V5, and inverted T wave in V5 and V6 after Master`s test. Simple chest X-ray finding showed emphysematous field, bilaterally. Final pre-operative diagnosis was made by coronary angiogram, which showed almost 90% degree of occlusive lesion in the proximal part of left main coronary artery above the origin LAD artery. He was treated successfully by aorta-coronary saphenous vein graft under extra-corporeal circulation in May, 1987. He has been followed up with uneventful course.

• Journal of Chest Surgery
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• v.35 no.9
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• pp.688-691
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• 2002

Takayasu's arteritis is a chronic inflammatory disease of unknown cause. It predominantly affects the aortic arch and its branches. Concomitant involvement of coronary and renal arteries is a rare entity. In this report, we described successful treatment of a patient with Takayasu's arteritis associated with coronary and renal arteries stenosis. A 23-year-old woman was presented with chest pain on exertion. Angiographic studies demonstrated left main coronary, bilateral renal, and left subclavian arteries stenosis. She underwent angioplasty and stenting of bilateral renal artery. After one week, coronary artery bypass grafting using greater saphenous veins and aorto-subclavian bypass with PTFE vascular graft were done simultaneously. She was discharged on the 13th postoperative day without any complications.

• Journal of Chest Surgery
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• v.26 no.5
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• pp.349-354
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• 1993

From July 1992 through January 1993, 11 patients with unstable angina received aorto-coronary bypass surgery at Dong-A University Hospital. There were 5 males and 6 females whose age ranged from 36 to 76 years old. Of the 11 patients, 3 were Functional class IL 5 were Functional class 111.3 were Functional class IV. Preoperative coronary angiography showed a significant stenosis of the left anterior descending artery in 9 cases, of its diagonal branch in I case, of the circumfiex artery in 3 cases, and of its obtuse marginal branch in 2 cases, of the right coronary artery in 4 cases, and of left main coronary artery in 3 cases. There were 4 cases of single vessel disease, 1 double vessel disease, 3 triple vessel disease and 3 left main disease. A single graft was placed in 1 patient, a double graft in 5, a triple graft in 2, and a quadriple graft in 3 patients. Left internal mammary artery plus saphenous vein graft were used in 4 patients. Postoperative complications were mediastinitis in 1, sternal instability in 2, pneumonia in 1, arrythmia in I case.

• Journal of Chest Surgery
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• v.18 no.2
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• pp.265-272
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• 1985

Congenital aneurysm of sinus of Valsalva is one of the rare congenital heart disease, which is usually asymptomatic until rupture. The aneurysm usually ruptures into a cardiac chamber and produces an aorto-intracardiac fistula. Ruptured aneurysm is a grave lesion in that it causes heart failure and subsequent death. If, however, it is discovered in its early stages and operated on properly, it can be corrected with considerable success. Form January 1975 through December 1984, 18 consecutive patients with congenital aneurysm of sinus of Valsalva underwent corrective surgery using total cardiopulmonary bypass in our department of Thoracic Surgery. 1. The incidence was about 0.9% of surgical cases of congenital heart disease during that period. 2. 13 were males and 5 females, with ages ranging 12 years to 52 years. 3. Associated anomalies were VSD in 14, infundibular PS in 1, aberrant muscle band in RVOT in 1, and secondary aortic insufficiency in 9. 4. 17 were suggested to arise from right coronary sinus and 1 from noncoronary sinus; Among 17, 12 ruptured into right ventricle, and one from noncoronary sinus into right atrium. 5. Surgical correction was performed by means of direct suture closure with combined pledget or patch graft after aneurysm resection, and associated lesions were also corrected simultaneously. 6. There was only one case of operative mortality, and all the other patients were relatively uneventful in their follow-up studies.

• Journal of Chest Surgery
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• v.12 no.4
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• pp.355-360
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• 1979

Mitral and aortic valve replacement with tricuspid annuloplasty was undertaken in 5 patients out of 38 valvular surgery between the period from Jan. 1977 to May 1979 in the Dept. of Thoracic and Cardiovascular Surgery in Korea University Hospital. All were male patients with age ranging from 18 to 42 years, and preoperative evaluation revealed one case in Class IV, and four cases in Class III according to the classification of NYHA. Preoperative diagnosis was confirmed by routine cardiac study including retrograde aorto- and left ventriculography, and there were two cases with MSi+ASi+Ti, two cases with MSi+Ai+Ti, and one case with Mi+Ai+Ti. Double valve replacement was performed under the hypothermic cardiopulmonary bypass with total pump time of 247 min. in average ranging from 206 min. to 268 min. During aortic valve replacement, left coronary perfusion was done in the first two cases, and cardiac arrest with cardioplegic solution proposed by Bretschneider was applied in the remained three cases. Starr-Edwards, Bjork-Shiley prosthetic valves and Carpentier-Edwards tissue valve were replaced in the aortic area, and Carpentier-Edwards and Angell-Shiley tissue valves were replaced in the mitral area with each individual combination [three prosthetic and two tissue valves in the aortic, and five tissue valves in the mitral area respectively]. Postoperative recovery was uneventful in all cases except one case with hemopericardium, which was managed with pericardiectomy on the postoperative 10th day in good result. Follow-up after double valve replacement of the all five cases for the period from 6 months to 33 months revealed satisfactory adaptation in social activity and occupation with cardiac function of Class I according to the classification of NYHA In all five cases.