• Journal of Chest Surgery
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• v.54 no.3
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• pp.165-171
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• 2021

As a percutaneous technique for the reduction of mitral regurgitation, the MitraClip system (Abbott Vascular, Abbott Park, IL, USA) for transcatheter edge-to-edge repair of the mitral valve was developed in 1998 and first used in 2003. Its main advantage is being less invasive than surgery, because it can be performed through a transcatheter approach without any hemodynamic compromise. Recent studies have shown that this procedure reduces symptoms and improves functional capacity with low complication rates. Two randomized clinical trials have investigated the use of this technique for functional mitral regurgitation. The Korean Ministry of Food and Drug Safety approved its use for degenerative mitral regurgitation in 2019, and this procedure started to be performed in Korea in January 2020. Its use for functional mitral regurgitation was also approved in Korea in 2020. In this article, recent evidence on transcatheter edge-to-edge repair of the mitral valve and our initial experiences in Korea will be reviewed.

• Journal of Chest Surgery
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• v.54 no.6
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• pp.449-453
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• 2021

The 2020 American College of Cardiology focused update on the mitral regurgitation (MR) pathway provides an excellent summary of the decision-making trees in the treatment of severe MR, in which 2 main branches of the flowchart are suggested depending on whether MR is primary or secondary. Surgery is suggested as preferable over transcatheter edge-to-edge repair (TEER) in primary MR that needs intervention. The decision-making for secondary MR generally prioritizes TEER over surgery according to the guidelines, but further stratification is necessary based on the pathophysiologic mechanisms of MR. TEER is probably the more suitable option in secondary MR caused by left ventricular dysfunction or dilatation, given the high perceived surgical risks, despite the lack of sufficient evidence in support of overt clinical benefits from surgical therapy in these patients. In atrial functional MR associated with atrial fibrillation (AF), however, concomitant ablation of AF seems to be a desirable option, as it has been demonstrated to be a key factor leading to improved survival, reduced stroke risk, and more durable mitral and tricuspid function in patients undergoing mitral surgery. Therefore, atrial functional MR requiring intervention may be best treated by surgical therapy that combines mitral repair and AF ablation in the majority of patients. This particular issue, however, needs further research to obtain scientific evidence to guide optimal management strategies.

• Korean Circulation Journal
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• v.53 no.11
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• pp.775-786
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• 2023

Background and Objectives: Tricuspid valve (TV) repair techniques other than annuloplasty remain challenging and frequently end in tricuspid valve replacement (TVR) in complicated cases. However, the results of TVR are suboptimal compared with TV repair. This study aimed to evaluate the clinical effectiveness of TV edge-to-edge repair (E2E) compared to TVR for severe tricuspid regurgitation (TR). Methods: We retrospectively reviewed 230 patients with severe TR who underwent E2E (n=139) or TVR (n=91) from 2001 to 2020. Clinical and echocardiographic results were analyzed using inverse probability of treatment weighting analysis and propensity score matching. Results: The two groups showed no significant differences in early mortality and morbidities. During the mean follow-up of 106.2±68.8 months, late severe TR and TV reoperation rates were not significantly different between groups. E2E group, however, showed better outcomes in overall survival (p=0.023), freedom from significant tricuspid stenosis (TS) (trans-tricuspid pressure gradient ≥5 mmHg, p=0.021), and freedom from TV-related events (p<0.001). Matched analysis showed consistent results. Conclusions: E2E for severe TR presented more favorable clinical outcomes than TVR. Our study supports that E2E might be a valuable option in severe TR surgery, avoiding TVR.

• Journal of Cardiovascular Imaging
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• v.31 no.1
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• pp.24-25
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• 2023

• Journal of Chest Surgery
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• v.56 no.1
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• pp.56-58
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• 2023

Untreated severe tricuspid regurgitation (TR) is associated with poor outcomes. Functional TR occurs secondary to dilatation of the annulus and tethering of the leaflets. Ring annuloplasty alone can correct most cases, but is insufficient in cases of severe annular dilatation due to severe leaflet tethering. In such cases, a tricuspid edge-to-edge technique may be an option. However, stitching of the leaflet tips alone is likely to result in tearing of the leaflets. Approximation of the durable chordae tendineae is considered helpful for this problem. Herein, we present the case of a 39-year-old man who had undergone open-heart surgery for acute type A aortic dissection 13 months earlier. A right mini-thoracotomy approach with a beating-heart strategy was used, which did not require unnecessary pericardial adhesiolysis and dissection. This technique had the advantage of reducing the operation time and the risk of bleeding. To summarize, we present a case of tricuspid valve repair in a high-risk patient with severe leaflet tethering that was successfully managed using these methods.

• Journal of Wind Energy
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• v.14 no.3
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• pp.43-53
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• 2023

To improve AEP, wind turbine blade lengths are increasing every year. As the length of blades increases, the blade tip speed also increases. Because of the increased tip speed, the impact energy between the leading edge and raindrops also increases. The increased impact energy is the primary factor contributing to erosion of the blade's leading edge. Blade leading edge erosion reduces aerodynamic performance, increases repair costs, and causes downtime. Therefore, numerous studies are being conducted on protective solutions and RET systems to prevent and delay erosion of the blade's leading edge. However, few institutions in Korea research protective solutions and RET systems. In this study, we aim to develop a laboratory-scale RET system. The developed RET system was based on the ASTM G73-10 standard. As a result of the RET, it was confirmed that the erosion tendency was similar to that of overseas institutions. In addition, the effectiveness of the RET system was verified by a maximum erosion rate of 0.0023 for an epoxy-based protective solution.

• Archives of Plastic Surgery
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• v.44 no.5
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• pp.453-456
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• 2017

Patients are increasingly seeking repair of their earlobes following ear gauging. Research has shown that current repair techniques either excessively reduce the lobular volume or leave an obvious scar along the free edge of the earlobe. In our case series, we describe the use of a novel technique for repairing earlobes following ear gauging using a rolling earlobe flap that preserves the lobular volume and avoids leaving a scar on the free edge of the lobule. The procedure was performed on 3 patients (6 earlobes) who had defects from ear gauging that ranged from 3.0 to 6.5 cm. There were no postoperative complications of infection, wound dehiscence, flap necrosis, hypertrophic scars, or keloids, and all patients were highly satisfied with the postoperative results. This versatile technique allows for an aesthetically pleasing reconstruction of the lobule with the advantages of: the absence of a surgical scar on the free edge of the lobule, preserving the lobule volume, and presenting a highly customizable technique that allows lobules to be created with various shapes and volumes.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.3
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• pp.101-110
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• 1991

The purpose of this study was to compare the repaired joint strength among several edge profiles after denture repair. For this study, eight edge profiles were used for repair methods and five self-curing resin brands were used for repair materials. Break away loads were tested after 1 hr., 24 hrs. and 1 week. Instron was used for testing the transverse strength of repaired specimen. The results were as follows. 1. Repaired joint strength was about 35-65% of that of original specimen. 2. Joint strengths of round, inverse knife, inverse rabbit, lap ogee joint were higher tnan that of traditional simple butt joint 3. Joint strength of the simple butt joint was low significant. 4. Joint strengths after 1 hr. specimen were lower than those of 24 hrs. and 1 week specimens in joint strengths. 5. There were no significant differences between 24 hrs. and 1 week specimens in joint strengths. 6. It look more than 24 hours to gain satisfactory physical property after repairing the fractured denture base when self-curing resin was used for repair.

• Journal of Information Processing Systems
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• v.16 no.5
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• pp.1129-1144
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• 2020

The thangka image inpainting method based on wavelet transform is not ideal for contour curves when the high frequency information is repaired. In order to solve the problem, a new image inpainting algorithm is proposed based on edge structural constraints and wavelet transform coefficients. Firstly, a damaged thangka image is decomposed into low frequency subgraphs and high frequency subgraphs with different resolutions using wavelet transform. Then, the improved fast marching method is used to repair the low frequency subgraphs which represent structural information of the image. At the same time, for the high frequency subgraphs which represent textural information of the image, the extracted and repaired edge contour information is used to constrain structure inpainting in the proposed algorithm. Finally, the texture part is repaired using texture synthesis based on the wavelet coefficient characteristic of each subgraph. In this paper, the improved method is compared with the existing three methods. It is found that the improved method is superior to them in inpainting accuracy, especially in the case of contour curve. The experimental results show that the hierarchical method combined with structural constraints has a good effect on the edge damage of thangka images.

• Journal of Chest Surgery
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• v.25 no.10
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• pp.1157-1160
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• 1992

Aortic valve repair with the use of tailored autologous pericardial extension to the native cusp was performed in one patient with rheumatic aortic valve incompetence. The patient was a 10-year-old girl with Grade II aortic regurgitation and tiny postoperative recannalization of the patent ductus arteriosus. The left aortic coronary cusp appeared to be a little thickened and a cicatrical shortening of the distance between the free edge of the cusp and its annular attachment. A semilunar shaped patch of autologous pericardium, treated with glutaraldehyde solution[6 minutes in 0.6% solution] was sutured along the free edge of the left coronry cusp. Postoperative recovery was uneventful. Echocardiography 8 months later showed Grade I aortic regurgitation. She is now conducting as usual life.