• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.542-546
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• 2008

In this study, we developed a whole cardiovascular system model combined with a Laplace heart based on the numerical cardiac cell model and a detailed arterial network structure. The present model incorporates the Laplace heart model and pulmonary model using the lumped parameter model with the distributed arterial system model. The Laplace heart plays a role of the pump consisted of the atrium and ventricle. We applied a cellular contraction model modulated by calcium concentration and action potential in the single cell. The numerical arterial model is based upon a numerical solution of the one-dimensional momentum equations and continuity equation of flow and vessel wall motion in a geometrically accurate branching network of the arterial system including energy losses at bifurcations. For validation of the present method, the computed pressure waves are compared with the existing experimental observations. Using the cell-system-arterial network combined model, the pathophysiological events from cells to arterial network are delineated.

• YAKHAK HOEJI
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• v.45 no.6
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• pp.739-745
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• 2001

Of all pesticides, carbamates are known to be most common, since alternatives such as organophosphates have long lifetime and are extremely toxic to produce a delayed neurotoxic effect. Although a number of studies about toxicity of carbofuran, a most widely used carbamate, have been reported, its cardiovascular toxicity has not yet been studied. In the present study, we investigated its cardiovascular toxic effect in anesthetized rat in vivo and in isolated Langendorff rat heart, In anesthetized rat model, carbofuran (10 mg/kg) significantly reduced heart rate, and transiently increased blood pressure. In isolated rat heart, carbofuran (10${\mu}{\textrm}{m}$) caused a significant depression in the left ventricular developed pressure (LVDP), indicating contractile dysfunction by carbofuran. Carbofuran (10${\mu}{\textrm}{m}$) also decreased coronary flow rate (CFR) in isolated heart, indicating carbofuran-induced coronary dysfunction. These results suggest that carbofuran can cause cardiac dysfunction in rat in vivo and vitro.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.187-200
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• 2006

Objectives: Acupuncture has been applied in Asia for thousands of years, especially to rehabilitation after stroke. It has been reported that acupuncture increased cerebral blood supply and stimulated the functional activity of brain nerve cells shown by using brain imaging techniques. This study was to evaluate the effect of GB 34-GB 39 electro-acupuncture (EA) on regional cerebral blood flow (rCBF) in stroke patients and normal volunteers using single photon emission computed tomography (SPECT). Methods: The study procedure was divided into two parts: patients and volunteers studies. For the patients study, ten ischemic stroke patients (3 males, 7 females, mean age $68.5{\pm}8.9$ years old) were selected. Baseline brain SPECT was done with triple head gamma camera (MultiSPECT3, Siemens, USA) after intravenous administration of 1,110 MBq of $^{99m}Tc-ECD$. Fifteen-minute EA at GB 34 and GB 39 were applied on the affected limb. The same dose of $^{99m}Tc-ECD$ was injected during the EA, and the second set of SPECT images wasobtained. Using the computer software (ICON 7.1, Siemens, USA), 3 SPECT slices (upper, middle, lower) surrounding the brain lesion were selected and each slice was divided into 10-16 brain regions. Asymmetry indexes (AI) were analyzed in each brain region. We regarded over 10% changes of AI between before and after EA as significance. For the volunteers study, 10 healthy human volunteers (5 males, 5 females, mean age $28.1{\pm}6$ years old) were selected. In the resting state, $^{99m}Tc-ECD$ brain SPECT scans were performed. On the 7th day after the resting examination, 15 minute EA was applied at GB 34 and GB 39 on the right side of the subjects. Immediately after EA, the second SPECT images were obtained inthe same manner as the resting state. Significant increases and decreases of rCBF after EA were estimated by comparing their SPECT images with those of the resting state using paired t statistics at every voxel, which were analyzed by statistical parametric mapping with a threshold of p = 0.01, uncorrected (extent threshold: k=100 voxels). Results: In stroke patients, six of the eight (75%) had significantly increased perfusion in post-acupuncture scans compared to their baseline state. In normal volunteers, GB 34-GB GB EA increased rCBF in both hemispheres including right ventral posterior cingulate (Brodmann area (BA) 23), left superior temporal, anterior transverse temporal (BA 22, 41), left parastriate, peristriate (BA 18, 19), right occipitotemporal, angular (BA 37, 39), left rostral postcentral, caudal postcentral and preparietal (BA 2, 3, 5). However GB 34-GB 39 EA decreased rCBF in the right hemisphere including triangular and middle frontal lobes. Conclusions: The results demonstrated that OB 34-GB 39 EA increased cerebral perfusion in ischemic stroke patients and increased rCBF grossly in temporal lobes of normal volunteers. It is also suggested that there may be a correlation between the GB meridian and the territory of the middle cerebral artery.

• Journal of Trauma and Injury
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• v.18 no.2
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• pp.172-174
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• 2005

Trauma of the vascular structure is not poplular event. In obstructive atherosclerotic vascular disease, we sometimes have needed bypass surgery. The long length subcutaneous prosthetic vascular graft are vulnerable to injury. But prosthetic vessel rupture after trauma has been rare report. A 68-year-old man was referred to Department of Emergency of the Gyeongsang National University Hospital. After he had had a blunt trauma, he found a newly appearing pulsating mass of 10 cm diameter on his right chest wall. The lesion had a turbulent blood flow in the cavity of the mass by ultrasonographic finding. The lesion was a rupture of superficial prosthetic vascular graft under the skin.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.248-251
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• 2009

Nonocclusive mesenteric ischemia (NOMI) is a rare complication that occurs in about 0.05% of patients after openheart surgery, and NOMI refers to the mesenteric ischemia that's caused by splanchnic vasospasm without occlusion of the great intestinal vessels. In the presently reported case, NOMI developed to maintain the blood flow to the heart and brain after several minutes of a hypotensive status and the latter was caused by acute aortic dissection that complicated an aortic cannulation procedure. Unfortunately, the patient died even though the problems were diagnosed early and proper treatment was administered. Early diagnosis of NOMI by angiography and the selective infusion of vasodilators are thought to be the only way to improve survival for patients with clinically suspected NOMI.

• Journal of Chest Surgery
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• v.38 no.7 s.252
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• pp.504-506
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• 2005

Intracavitary coronary artery is variant anomalous entrance to right ventricular cavity of left anterior descending artery. Since the disease is extremely rare, there has not been any report of it in Korea and is only found in $0.2\~0.3\%$ of all CABG patients. It is very difficult to be diagnosed by preoperative coronary arteriography (CAG) and secure suture is needed for right ventriculotomy after CABG due to bleeding from right ventricle. Horizontal mattress suture with pledget has been recommended but, it could compress the myocardium surrounding ventriculotomy and result in disturbed flow of left anterior descending artery branch and perforating artery. So we used simple interrupted suture and the patient was recovered as other CABG patients without complications.

• Journal of Chest Surgery
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• v.39 no.2 s.259
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• pp.145-149
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• 2006

The surgical management of patients with transposition of the great arteries, ventricular septal defect, and pulmonary stenosis remains a challenge. The Rastelli operation or Lecompte operation is the preferred surgical procedure, but its long-term results are not optimal because of a warped left ventricular outflow tract through a space-occupied intraventricular tunnel and a contrived right ventricular outflow tract. We performed a half-turned truncal switch operation as an alternative surgical procedure in a 3-year-old boy (weighing 9.6 kg) with this anomaly. Postoperative echocardiography showed laminar flow through straight and nonobstructive aortic and pulmonary ventricular outflow tracts.

• Journal of Chest Surgery
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• v.53 no.1
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• pp.28-33
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• 2020

Background: When an arteriovenous fistula (AVF) is created using the basilic or deep cephalic vein, it is additionally necessary to transfer the vessels to a position where needling is easy; however, many patients develop wound-related postsurgical complications due to the long surgical wounds resulting from conventional superficialization of a deep AVF or basilic vein transposition. Thus, to address this problem, we performed videoscopic surgery with small surgical incisions. Methods: Data from 16 patients who underwent additional videoscopic radiocephalic superficialization, brachiocephalic superficialization, and brachiobasilic transposition after AVF formation at our institution in 2018 were retrospectively reviewed. Results: Needling was successful in all patients. No wound-related complications occurred. The mean vessel size and blood flow of the AVF just before the first needling were 0.73±0.16 mm and 1,516.25±791.26 mL/min, respectively. The mean vessel depth after surgery was 0.26±0.10 cm. Percutaneous angioplasty was additionally performed in 25% of the patients. Primary patency was observed in 100% of patients during the follow-up period (262.44±73.49 days). Conclusion: Videoscopic surgery for AVF dramatically reduced the incidence of postoperative complications without interrupting patency; moreover, such procedures may increase the use of native vessels for vascular access. In addition, dissection using a videoscope compared to blind dissection using only a skip incision dramatically increased the success rate of displacement by reducing damage to the dissected vessels.

• Journal of Chest Surgery
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• v.57 no.3
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• pp.263-271
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• 2024

Background: Delirium is a recognized neurological complication following cardiac surgery and is associated with adverse clinical outcomes, including elevated mortality and prolonged hospitalization. While several clinical risk factors for post-cardiac surgery delirium have been identified, the pathophysiology related to the immune response remains unexamined. This study was conducted to investigate the immunological factors contributing to delirium in patients after thoracic aortic surgery. Methods: We retrospectively evaluated 43 consecutive patients who underwent thoracic aortic surgery between July 2017 and June 2018. These patients were categorized into 2 groups: those with delirium and those without it. All clinical characteristics were compared between groups. Blood samples were collected and tested on the day of admission, as well as on postoperative days 1, 3, 7, and 30. Levels of helper T cells (CD4), cytotoxic T cells (CD8), B cells (CD19), natural killer cells (CD56+CD16++), and monocytes (CD14+CD16-) were measured using flow cytometry. Results: The median patient age was 71 years (interquartile range, 56.7 to 79.0 years), and 21 of the patients (48.8%) were male. Preoperatively, most immune cell counts did not differ significantly between groups. However, the patients with delirium exhibited significantly higher levels of interleukin-6 and lower levels of tumor necrosis factor-alpha (TNF-α) than those without delirium (p<0.05). Multivariate analysis revealed that lower TNF-α levels were associated with an increased risk of postoperative delirium (p<0.05). Conclusion: Postoperative delirium may be linked to perioperative changes in immune cells and preoperative cytokine levels. Additional research is required to elucidate the pathophysiological mechanisms underlying delirium.

• Journal of Chest Surgery
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• v.38 no.10 s.255
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• pp.661-668
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• 2005

Background: We have hypothesized that, if a low resistant gravity-flow membrane oxygenator is used, then the twin blood sacs of TPLS can be located at downstream of the membrane oxyenator, which may double the pulse rate at a given pump rate and increase the pump output. The purpose of this study was to determine the optimal configuration for the ECLS circuits by using the concept of pulse energy and pump output. Material and Method: Animals were randomly assigned to 2 groups in a total cardiopulmonary bypass model. In the serial group, a conventional membrane oxygenator was located between the twin blood sacs. In the parallel group, the twin blood sacs were placed downstream of the gravity-flow membrane oxygenator. Energy equivalent pressure (EEP) and pump output were collected at pump-setting rates of 30, 40, and 50 BPM. Result: At the given pump-setting rate, the pulse rate was doubled in the parallel group. Percent changes of mean arterial pressure to EEP were $13.0\pm1.7,\; 12.0\pm1.9\;and\;7.6\pm0.9\%$ in the parallel group, and $22.5\pm2.4,\; 23.2\pm1.9,\;and\;21.8\pm1.4\%$ in the serial group at 30, 40, and 50 BPM of pump-setting rates. Pump output was higher in the parallel circuit at 40 and 50 BPM of pump-setting rates $(3.1\pm0.2,\;3.7\pm0.2L/min\;vs.\;2.2\pm0.1\;and\;2.5\pm0.1L/min,\;respectively,\;p=0.01)$. Conclusion: Either parallel or serial circuit configuration of the ECLS generates effective pulsatility. As for the pump out, the parallel circuit configuration provides higher flow than the serial circuit configuration.