• Advances in biomechanics and applications
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• v.1 no.4
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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 Mechanical Science and Technology
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• v.19 no.6
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• pp.1313-1320
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• 2005

Stenosed coronary artery may play an important role in various coronary heart diseases. However, it has not been known how much stenosed coronary artery affects coronary circulation system, quantitatively. The present study developed a mathematical model for microcirculation in the left common coronary artery (LCCA) with adopting a previously measured morphological data and mechanical properties of the coronary vessels. We examine the effect of percent diameter stenosis on blood flow rate and shear stress for two cases. Case I comprised of one-stenosed element at $10^{th}$ order ($\%$ diameter stenosis are 10, 30, and 50, respectively). Case II consisted of completely occluded element at $10^{th}$ order (number of occluded elements are 0, 1, and 2 out of 8, respectively). As the level of stenosis becomes severe, the shear stress increases significantly but the flow rate reduction was relatively small. However, for the occluded case, there was linearly proportional reduction of flow rate according to number of occluded elements. Either such high shear stress associated with coronary artery stenosis or reduced flow rate due to occlusion may cause atherosclerosis and myocardial ischemia.

• International Journal of Vascular Biomedical Engineering
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• v.2 no.1
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• pp.25-30
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• 2004

Catheters are used to measure translesional pressure gradients in the stenosed coronary arteries. Uses of catheters during coronary angioplasty cause flow obstructions. A narrowed flow cross section with catheter effectively introduced a tighter stenosis than the enlarged residual stenoses after balloon angiplasty. Catheters in blood vessels cause pressure gradient rise and blood flow drop during the measurements. In this study, three dimensional computer simulations are conducted to investigate the flow blockage effects due to the catheter obstructions during the coronary angioplasty. The computer simulation models are generated by the data, which are measured by coronary angiogram, and the blood is treated as non-Newtonian fluid. The velocity, pressure, and wall shear stress variations are observed for the estimate of damages of blood vessel. This study is also extended to investigate the effects of stenotic vessel size, and shape and catheter size and location.

• Clinical and Experimental Pediatrics
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• v.59 no.sup1
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• pp.80-83
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• 2016

Isolated anomalous right coronary artery originating from the pulmonary artery (ARCAPA) is a rare congenital coronary anomaly that is asymptomatic and discovered incidentally in most cases. ARCAPA is generally not considered a fatal defect in infancy or childhood, although cases of sudden death have been reported. Here, we report a 2-month-old female infant who presented with a prolonged fever that was determined to be caused by rhinovirus infection. Myocardial ischemia of the left ventricular posterior wall was already seen on echocardiography, and ARCAPA was discovered incidentally. The patient underwent successful surgical reimplantation of the right coronary artery to the aortic root to re-establish dual ostial circulation.

• 순환기질환의공학회:학술대회논문집
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• 2001.11a
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• pp.53-54
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• 2001

• 순환기질환의공학회:학술대회논문집
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• 2002.11a
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• pp.50-51
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• 2002

• 순환기질환의공학회:학술대회논문집
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• 2004.11a
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• pp.9-10
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• 2004

• 순환기질환의공학회:학술대회논문집
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• 2003.11a
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• pp.33-33
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• 2003

• Korean Circulation Journal
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• v.53 no.3
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• pp.189-190
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• 2023

• Korean Circulation Journal
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• v.53 no.6
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• pp.421-424
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• 2023