• Journal of Chest Surgery
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• v.41 no.2
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• pp.160-169
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• 2008

Bakcground: To treat anastomosis site stenosis and occlusion of the artificial vessels used in vascular surgery, tissue-engineered artificial vessels using autologous cells have been constructed. We developed artificial vessels using a polymer scaffold and autologous bone marrow cells and performed an in vivo evaluation. Material and Method: We manufactured a vascular scaffold using biodegradable PLCL (poly lactide-co-${\varepsilon}$-caprolactone) and PGA (poly glycolic acid) fibers. Then we seeded autologous bone marrow cells onto the scaffold. After implantation of the artificial vessel into the abdominal aorta, we performed an angiography 3 weeks after surgery. After the dogs were euthanized we retrieved the artificial vessels and performed histological analysis. Result: Among the six dogs, 2 dogs died of massive bleeding due to a crack in the vascular scaffold 10 days after the operation. The remaining four dogs lived for 3 weeks after the operation. In these dogs. the angiography revealed no stenosis or occlusion at 3 weeks after the operation. Gross examination revealed small thrombi on the inner surface of the vessels and the histological analysis showed three layers of vessel structure similar to the native vessel. Immunohistochemical analysis demonstrated regeneration of the endothelial and smooth muscle cell layers. Conclusion: A tissue engineered vascular graft was manufactured using a polymer scaffold and autologous bone marrow cells that had a structure similar to that of the native artery. Further research is needed to determine how to accommodate the aortic pressure.

• International Journal of Vascular Biomedical Engineering
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• v.1 no.2
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• pp.20-29
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• 2003

A new treatment for coronary artery occlusive disease is being developed in which a shunt or conduit is placed directly connecting the left ventricle with the diseased artery at a point distal to the obstruction. To aid in assessing and optimizing its benefit, a computational model of the cardiovascular system was developed and used to explore various design conditions. Simulation results indicate that in complete LAD occlusion, flow can be returned to approximately 65% of normal if the conduit resistance is equal for forward and reverse flow, increasing to 80% in the limit in which backflow resistance is infinite. Increases in flow rate produced by asymmetric flow resistance are considerably enhanced in the case of a partial LAD obstruction since the primary effect of resistance asymmetry is to prevent leakage back into the ventricle("steal") during diastole. Increased arterial compliance has little effect on net flow with a symmetric shunt, but leads to considerable augmentation when the resistance is asymmetric. These results suggest that an LV-LAD conduit will be beneficial when stenosis resistance(Rst) > 27 PRU if resistance is symmetric.

• Physical Therapy Rehabilitation Science
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• v.1 no.1
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• pp.6-12
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• 2012

Objective: Coenzyme (CoQ10) is an enzymatic co factor used in normal cellular metabolism. Recent evidence shows that in people with heart disease it can reverse endothelial cell damage in the blood vessels. It is also a potent antioxidant. Design: One group pretest-posttest design. Methods: In the present study, endothelial function was evaluated using the response to occlusion and heat before and 2 weeks after administration of CoQ10, 300 mg/day. Thirty Eight subjects, who are physical therapy students, participated in a series of experiments to see if taking 300 mg of CoQ10 daily for 2 weeks would impact resting blood flow in the forearm skin and the blood flow response to 4 minutes of vascular occlusion and the response to local heat ($42^{\circ}C$) for 6 minutes. Results: The results showed that, for this population, there was no difference in the response to heat. However, the response to occlusion was improved after administration of CoQ10. Conclusions: It would appear that in a young population CoQ10 has no effect on the nitric oxide vasodilator pathway in skin but does influence other vasodilator pathways.

• Journal of Chest Surgery
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• v.38 no.10 s.255
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• pp.710-713
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• 2005

Acute abdominal Aortic occlusion is rare but it is a vascular emergency with high mortality and morbidity. There­fore, delay in diagnosis can have severe impact on the prognosis. A 60-year-old women complained of paresthesia, paralysis, and severe pain in bilateral lower extremities on 13th day after open heart surgery for mitral stenosis, atrial fibrillation, coronary arterial stenosis, tricuspid regurgitation, and atrial septal defect. Her skin was mottled and cool from the umbilicus to the feet, and there were no palpable pulses in the lower exteremities. We diagnosed an acute abdominal aortic occlusion using the Multi-Detector Row Spiral Computed Tomography and successfully treated the problem with emergent thrombo-embolectomy and Aortobifemoral bypass.

• Journal of Chest Surgery
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• v.40 no.11
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• pp.773-776
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• 2007

A 47-year-old male with hypertension, diabetes mellitus and heavy smoking, but no anginal symptoms, presented with claudication of the lower extremities. Extremity angiography with coronary angiography revealed peripheral arterial lesions including a left subclavian artery occlusion with coronary artery disease. The patient underwent an initial off-pump coronary artery bypass with an ascending aorto-axillary bypass. The right internal mammary artery was anastomosed to the left anterior descending coronary artery. The greater saphenous vein graft was connected from the ascending aorto-axillary bypass graft to the diagonal branch. At postoperative day 18, femorofemoral and bilateral femoropopliteal bypasses were performed. We report a case of the combined repair of coronary artery disease and a left subclavian artery occlusion.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.98-100
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• 2003

Synthetic polymers such as PET and ePTFE have widely been used for artificial vascular patches. However, these materials cannot function for a long term as blood vessel due to thrombotic occlusion and calcification. To overcome this limitation, a biocompatible vascular patch was developed using stem cell and tissue engineering approach. Autologous bone marrow mesenchymal stem cells were differentiated into vascular endothelial cells and smooth muscle cells. These cells were seeded onto collagen patch matrices. The matrices were anastomosed to abdominal arteries in canine models. Prior to implantation, histological and scanning electron microscopical examination revealed stem cell adhesion and growth on the matrices. At 3 weeks, the implanted vascular patches were patent. Histological examination showed the regeneration of endothelium, media and adventitia in the grafts. Cell tracing analysis using fluorescent reagent showed that labeled stem cells were present in the implanted grafts and contributed to the regeneration of vascular tissues. This study may help us develop a tissue-engineered vascular patch appropriate for clinical applications.

• Journal of Pharmacopuncture
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• v.20 no.1
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• pp.23-28
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• 2017

Objectives: Exercise with partially restricted blood flow is a low-load, low-intensity resistance training regimen which may have the potential to increase muscle strength in the obese, elderly and frail who are unable to do high-load training. Restricted blood flow exercise has also been shown to affect blood vessel function variably and can, therefore, contribute to blood vessel dysfunction. This pilot study tests the hypothesis that unilateral resistance training of the leg extensors with partially restricted blood flow increases muscle strength and decreases vascular autoregulation. Methods: The subjects were nine normotensive, overweight, young adult African-Americans with low cardiorespiratory fitness who underwent unilateral training of the quadriceps' femoris muscles with partially restricted blood flow at 30% of the 1-repetition maximum (1-RM) load for 3 weeks. The 1-RM load and post-occlusion blood flow to the lower leg (calf) were measured during reactive hyperemia. Results: The 1-RM load increased in the trained legs from $77{\pm}3$ to $84{\pm}4 kg$ (P < 0.05) in the absence of a significant effect on the 1-RM load in the contralateral untrained legs (P > 0.1). Post-occlusion blood flow decreased significantly in the trained legs from $19{\pm}2$ to $13{\pm}2mL{\cdot}min^{-1}{\cdot}dL^{-1}$ (P < 0.05) and marginally in the contralateral untrained legs from $18{\pm}2$ to $16{\pm}1mL{\cdot}min^{-1}{\cdot}dL^{-1}$ (P = 0.09). Changes in post-occlusion blood flow to the skin overlying the trained and the contralateral untrained muscles were not significant. Conclusion: These results demonstrate that restricted blood flow exercise, which results in significant gains in muscle strength, may produce decrements in endothelial dysfunction and vascular autoregulation. Future studies should determine whether pharmacopuncture plays a role in treatments for such blood vessel dysfunction.

• Journal of Korean Neurosurgical Society
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• v.49 no.4
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• pp.226-228
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• 2011

We report a case of spontaneous right carotid-cavernous fistula (CCF) in a proximal segment of persistent primitive trigeminal artery (PPTA) and combined vascular anomalies such as left duplicated hypoplastic proximal posterior cerebral arteries and a variation of anterior choroidal artery supplying temporal and occipital lobe. A 45-year-old male presented with progressive right exophthalmos, diplopia, and ocular pain. With manual compression of the internal carotid artery, a cerebral angiography revealed a right CCF from a PPTA. Treatment involved the placement of detachable non-fibered and fibered coils, and use of a hyperglide balloon to protect against coil herniation into the internal carotid artery. A final angiograph revealed complete occlusion of PPTA resulted in no contrast filling of CCF.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.38-40
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• 1995

There have reports suggested that cerebral blood flow (CBF) has decreased in patients with both senile dementia of the Alzheimer's type and multi-infarct dementia, which are characterized by marked cognitive impairments. In addition, recent studies have demonstrated that decrease of CBF precedes the onset of multi-infarct dementia. These findings further suggest that chronic reduction of CBF may play an important role in the formation and progression of cerebral vascular dementia. Although transient cerebral ischemia, based upon vascular “reperfusion”, is apparently not paralleling the clinical condition, the transient cerebral ischemia model is one of the major methods investigated and the other is the cerebral embolism operation. Cognitive impairment and neuronal damages have been fully studied using these transient and/or embolic ischemia models. There are, however, few investigations focused the attention on the influence of chronic decrease of CBF on cognitive processes. In the present study, we have chosen a chronic ischemic model which is produced by permanent occlusion of bilateral common carotid arteries (2VO) in rats to investigate the neuronal damage and cognitive deficits through radial maze performance. We investigated furtherly the effects of tetramethylpyrazine (TMP), a constituent isolated from Ligusticum Chuanxiong on such a model.

• Journal of Chest Surgery
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• v.25 no.12
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• pp.1570-1577
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• 1992

The vascular surgery is the field that has developed in early 20 century and is progressing nowadays. Recent advance in surgical technique accompanying with excellent medical diagnosis and treatment, prompt angiographic usage, development of variable prosthetic material, and concomitant use of anti-coagulant have made remarkable results of vascular surgery. 83 cases of vascular surgery have been performed at Thoracic and Cardiovascular Surgery Department of Pusan National Unversity Hosaital since 1971 till 1990, for 20 years and their results are followed. Patient ductus arteriosus and Buerger`s disease were omited in this study. 1. The age distribution shows that the fifth and sixth decades are most frequently affected and mean age was 56.1 years old. Male to female ratio is 1: 2.32. 2. Among the 83 cases of all, number of occlusive vascular disease is 46 and that of aneurysmal disease is 33. 3. In clinical manifestation, most common symptom of occlusive disease is pulselessness and pain was next. Mass sensation is most commonly complained by patients of aneurysmal disease. 4. CT scan was more important in diagnosis of aneurysmal diseases and angiogram was more commonly used in occlusive diseases. 5. The common site of arterial occlusion was common iliac artery, femoral artery, aortic bifurcation, and external iliac artery, as its frequency rate. The most commonly affecting portion of aortic aneurysm was abdminal aorta, and descending thoracic aorta and femoral artery were next 6. Preoperative associated diseases were atherosclerosis[41 cases], hypertension[21 cases], valvular heart disease[11 cases], and diabetes mellitus[9 cases], etc, 7. Operative methods in ocllusive diseases were thrombectomy[36.9%], endarterectomy [10.9%], and bypass graft insertion[52.7%]. Among the bypass graft, Y-graft was used in 7 case, straight graft was used in 17 cases, and saphenous venous graft was used in 2 cases. 8. Postoperative complications were developed in 17 cases, and morbidity rate was 36. 9. Eleven patient were died within 1 month after operation, so operative mortality rate was 13.3%. 10. Duration of patency was beteween 7 and 58 months[average 27.5 months] in occlusive diseases and their 5-year patency rate was 56.3%. Duration of patency of aneurysmal disease was 20 months in aveage and their 5-year patency rate was 51.3%. 11. Patients of eleven cases of occlusive disease and two cases of aneurysmal disease required reoperation for variable reason. 12. 35 cases of patient have used anticoagulants: coumadin, ticlid, and persanthin-ASA combination.