• 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.36 no.12
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• pp.995-998
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• 2003

During coronary artery bypass surgery, there are several discrete maneuvers that facilitates localization of the invisible left anterior descending coronary artery. In some cases with intramyocardial left anterior descending artery, long-term patency of a bypassed graft may depend on anastomosing the internal mammary artery graft to the more proximal and superficial site of the intramyocardial left anterior descending artery. We describe an easy technique to locate the proximal superficial left anterior descending artery with a distal coronary arteriotomy and retrograde insertion of a coronary probe.

• Journal of Chest Surgery
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• v.28 no.3
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• pp.253-257
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• 1995

Forty-eight patients with significant left main coronary artery obstruction underwent coronary artery bypass graft between September,1989 and September,1993. They consisted of 29 males and 19 females with the mean age of 58 [range 33 - 78 . Seventeen patients[35% had stenosis in left main coronary artery only and twenty-nine[61% had associated lesions in other coronary artery systems as well.Two[4% had isolated left coronary ostial lesion. The operative mortality was 4.17% [2/48 which is comparable to the mortality of overall coronary artery bypass surgery cases during the same period[p >0.05 . Perioperative myocardial infarction was occurred in two patients[4.17% . And the infarction rates between the two groups also showed no difference[p >0.05 . The forty-six survivors showed significant improvement in exercise tolerance as well as symptomatology. We conclude that surgery for left main coronary artery disease can be done with no increased risk through careful anesthesia,surgery, and aggressive postoperative care in the critical period.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.499-501
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• 2001

In the 1970s, the radial artery was proposed as a coronary artery bypass graft but then was abandoned due to graft occlusion secondary to spasm during harvesting. Development of new pharmacologic antispasmodic agents and minimal traumatic harvesting techniques has led to the revival of the use of the radial artery in coronary artery bypass procedures. Harmonic Scalpel(Ultracision Inc, Smithfield, Rl) offers the surgeon the ability to perform less traumatic, spasm free, and rapid radial artery harvesting.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.10 no.2
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• pp.123-131
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• 2003

This study was to compare the functional status. complication and readmission rates. and client satisfaction with nursing care of home-based care and hospital-based care for clients with Coronary Artery Bypass Graft. Raw data were collected by interviewing and reviewing charts of 41 clients with Coronary Artery Bypass Graft between June 2001 and July 2002 at an university hospital located in Seoul. Korea. Out of 41 clients. 15 were in home care group and 26 were in hospitalization group. The baseline characteristics of the groups were almost identical. Mean age was 61.7 and 75.6% of clients being male. For home care group. the data collection was made at discharge and at termination of home care. and for hospitalization group. at discharge and at the first visit of outpatient department. Complication and readmission rates were investigated at one month after operation. Collected data were then analysed by conducting Chi-square test. Wilcoxon rank sum test. and Wilcoxon signed ranks test with SPSS program. The level of significance was .05. The results of the study are summarized as follows: 1. Postoperative length of stay of the home care group was shorter than that of hospitalization group by 1. 14 days(8.45 days vs. 9.59 days). On average. 1.8 home visits per client were observed. 2. The functional status (Barthel Index) at the termination of home care was significantly increased from that at discharge. For hospitalization group. a significant increase was observed between the functional status at the discharge and that at the first visit of outpatient department. The differencies in incremental of the scores. between the groups. were however not significant. 3. Complication and readmission rates; no statistically significant difference between the groups was observed. 4. The client satisfaction with nursing care (CSS) at termination of home care was significantly higher than that at hospital discharge. In conclusion. the outcomes of the analysis suggest that the home care benefits clients with Coronary Artery Bypass Graft. Client satisfaction with nursing care rises at termination of home care as compare to that measured at hospital discharge. Meanwhile. there was no significant differences in functional status. and complication and readmission rates. Further. home care reduced the length of stay in hospital.

• Journal of Chest Surgery
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• v.22 no.6
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• pp.1092-1100
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• 1989

Since May 1987 to April 1989, fifteen patients have been subjected to coronary artery bypass graft [CABG] including coronary thromboendarterectomy in 3 patients at Hanyang University Hospital. The correlation between the preoperative coronary angiography, electrocardiography, clinical status, operative finding and postoperative blood flow, complication and degree of clinical improvement were evaluated. 1. Ten patients [67 %] were male and five patients [33 %] were female, Ages ranged from 30 to 68 years. [average 52.2 years] 2. The angina by types of presentation was stable in 3 patients, unstable in 12 patients with resting, postinfarction and progressive angina as the criteria of unstability. 3. The number of involved vessels were single in 6 cases, double in 4 cases, triple in 5 cases including 1 case of left main coronary arterial disease. 4. The distribution of sites of distal anastomosis revealed predilection to left coronary arterial system [83 %], especially left anterior descending arterial system. 5. The author performed 4 cases of single bypass, 4 cases of double bypass, 5 cases of triple bypass and 2 cases of quadruple bypass. Of these 15 patients, 3 patients received coronary thromboendarterectomy, LAD in 2 patients and right coronary artery [RCA] in 1 patient. 6. The distal anastomosis were performed first with using saphenous vein grafts as conduits in all cases except 1 case using Gore-Tex conduit because of deficient in length and narrowed internal mammary artery and sequential bypass methods were employed in last 6 cases. 7. One operative death occurred and therefore, mortality rate was 6.7%. The perioperative myocardial infarction were occurred in 3 cases [20%] and its cause was supposed that they were triple vessel disease and therefore, aortic cross clamping times were relatively long. 8. All survivors were followed for 17.7 months on an average [range 5-28 months] and they have had symptomatic improvement except 1 case having mild degree of angina at 1.5 months after operation.

• Journal of Mechanical Science and Technology
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• v.19 no.3
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• pp.905-912
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• 2005

A computational investigation of blood flow in a coronary artery grafted by artificial bypass was performed to determine such geometric parameters as the curvature of radius, approach length, and angle of end-to-side anastomosis. Transient flow features in the host artery were computed using FVM and SIMPLE algorithms. We compared flow distributions and wall shear stresses in two simple models, planar and non-planar, and confirmed that the non-planar bypass model was more conducive to suppressing intimal hyperplasia. Our non-planar model with $60^{\circ}$ of anastomosis and a 1.0 diameter approach length and radius of curvature predicts a relatively small, spatially-extended high-OSI (>0.01) zone, as well as an increased average wall shear stress on this zone.

• Journal of Chest Surgery
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• v.35 no.12
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• pp.898-901
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• 2002

It is now widely accepted that the complete arterial coronary revascularization has better short and long term results compared to coronary bypass surgery using arterial graft mixed with vein graft mainly due to its superior patency rate. However, sometimes the internal thoracic artery and other conventionally used grafts might be unavailable or it may require caution in using bilateral internal thoracic artery especially in diabetic patient because of the possible risk of the mediastinitis or other associated morbidities. Moreover, there could also be a shortage for arterial graft in case of coronary reoperation. We report our first three cases using thoracodorsal artery(TDA) as an alternative graft in complete arterial coronary revascularization.

• Journal of Chest Surgery
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• v.21 no.5
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• pp.842-849
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• 1988

Between July, 1987, and September, 1988, 6 patients with coronary occlusive disease received coronary artery bypass surgery at Kyungpook University Hospital. There were five males and one female whose age ranged from 39 to 64 years[mean 54*8.0 years]. Of the 6 patients, 5 suffered from unstable angina, 1 suffered from stable angina. Selective coronary angiography revealed a significant stenosis of the left anterior descending artery in 6 cases, of its diagonal branch in 1 case, of the right coronary artery in 1 case, the circumflex artery in 1 case, and of its obtuse marginal branch in 1 case. The mode of anastomosis were single saphenous vein graft in 3 cases, single left internal mammary artery graft in 1 case, double saphenous vein graft with sequential anastomosis in 1 case, and left internal mammary artery plus saphenous vein graft in 1 case. Of these, 6 grafts to left anterior descending artery were done. There was no operative death, but perioperative myocardial infarction was happened in 1 case. All survivors were free of angina and discontinuing medical therapy during the follow up period[mean 7.8*5.15 months].

• Journal of Chest Surgery
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• v.48 no.3
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• pp.206-209
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• 2015

Ascending aortic aneurysms are usually treated with graft replacement under cardiopulmonary bypass. However, if a candidate for off-pump coronary artery bypass grafting has an enlarged ascending aorta, surgeons may consider wrapping it without cardiopulmonary bypass. Here, we report a 78-year-old female who underwent successful wrapping of the ascending aorta concomitant with off-pump coronary artery bypass grafting, using a new wrapping technique that involves multiple bootstraps.