• Korean Journal of Radiology
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• v.24 no.7
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• pp.647-659
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• 2023

Objective: The study was conducted to investigate the effect of correct occlusion of the left atrial appendage (LAA) on intracardiac blood flow and thrombus formation in patients with atrial fibrillation (AF) using four-dimensional (4D) flow magnetic resonance imaging (MRI) and three-dimensional (3D)-printed phantoms. Materials and Methods: Three life-sized 3D-printed left atrium (LA) phantoms, including a pre-occlusion (i.e., before the occlusion procedure) model and correctly and incorrectly occluded post-procedural models, were constructed based on cardiac computed tomography images from an 86-year-old male with long-standing persistent AF. A custom-made closed-loop flow circuit was set up, and pulsatile simulated pulmonary venous flow was delivered by a pump. 4D flow MRI was performed using a 3T scanner, and the images were analyzed using MATLAB-based software (R2020b; Mathworks). Flow metrics associated with blood stasis and thrombogenicity, such as the volume of stasis defined by the velocity threshold ($\left|\vec{V}\right|$ < 3 cm/s), surface-and-time-averaged wall shear stress (WSS), and endothelial cell activation potential (ECAP), were analyzed and compared among the three LA phantom models. Results: Different spatial distributions, orientations, and magnitudes of LA flow were directly visualized within the three LA phantoms using 4D flow MRI. The time-averaged volume and its ratio to the corresponding entire volume of LA flow stasis were consistently reduced in the correctly occluded model (70.82 mL and 39.0%, respectively), followed by the incorrectly occluded (73.17 mL and 39.0%, respectively) and pre-occlusion (79.11 mL and 39.7%, respectively) models. The surfaceand-time-averaged WSS and ECAP were also lowest in the correctly occluded model (0.048 Pa and 4.004 Pa^-1, respectively), followed by the incorrectly occluded (0.059 Pa and 4.792 Pa^-1, respectively) and pre-occlusion (0.072 Pa and 5.861 Pa^-1, respectively) models. Conclusion: These findings suggest that a correctly occluded LAA leads to the greatest reduction in LA flow stasis and thrombogenicity, presenting a tentative procedural goal to maximize clinical benefits in patients with AF.

• Journal of Chest Surgery
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• v.22 no.4
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• pp.693-697
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• 1989

A forty-eight-year-old female patient with ascending aortic aneurysm with aortic insufficiency underwent a modified Bentall operation. The ascending aorta and the aortic valve were replaced with a composite graft containing a St. Jude valve. The coronary orifices were anastomosed to the tubular Dacron prosthesis by means of a second smaller Gore-Tex tube, and a fistula between the aneurysmal sac and the right atrial appendage was created to drain oozing from the prosthesis. The postoperative course was uneventful and the patient was discharged without complication. She is doing well on the 14 months follow-up.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.368-371
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• 1995

This paper describes dynamic analysis and attitude control of a large spacecraft with flexible appendages in gravitational field. The effect of attitude control and vibration control of flexible appendages in gravitational field has been clarified. We demonstrate some simulations in gravitational field for some cases, and suggest the effects of gravitational torque, parameters of flexible appendages, attitude control and vibration control of flexible appendages.

• Journal of Chest Surgery
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• v.19 no.3
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• pp.449-452
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• 1986

A patient with benign superior vena cava syndrome caused by the thrombus and fibrotic membrane in superior vena cava is described. Surgical treatment of superior vena cava syndrome remains controversial still. After endvenectomy and thrombectomy of superior vena cava, angioplasty with use of Gore-Tex patch and bypass graft using 10mm diameter Dacron vessel graft from left innominate vein to right atrial appendage were performed. The early postoperative course was uneventful with achievement of good decompression. But 12 months later, the symptoms of superior vena cava syndrome were reoccurred.

• Mycobiology
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• v.28 no.1
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• pp.39-46
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• 2000

Eight species of Marssonina parasitic on 21 species of host plants from Korea are described and illustrated. They are Marssonina brunnea (Ellis & Everh.) Magnus, M. capsulicola (Rostr.) Magnus, M. celastri H.D. Shin & H.T. Lee, M. coronaria (Ellis & Davis) Davis, M. fragariae (Lib.) Kleb., M. juglandis (Lib.) Magnus, M. rosae (Lib.) Died. and M. sennenis (Gonz. Frag.) Vassiljevsky & Karak. Of these, M. capsulicola and M. coronaria sometimes poss three-celled conidia and M. sennenis is characterized by a short appendage at the basal end of the conidia. Morphological features of conidia and host ranges were of taxonomic values for species delimitation.

• Journal of Ocean Engineering and Technology
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• v.13 no.1 s.31
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• pp.18-22
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• 1999

One of the problem areas in designing a barge is its resistance and corese stability when it is towed by a tugboat. In this paper, as a part of design of a incinerating vessel, the results of some experimental studies on the effect of various kinds of anti-yawing skegs to the course keeping stability and on the additional resistance caused by them were summarized.

• Journal of Chest Surgery
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• v.47 no.2
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• pp.94-99
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• 2014

Background: Surgical repair of a partial anomalous pulmonary venous connection (PAPVC) to the superior vena cava (SVC) may be complicated by sinus node dysfunction or SVC obstruction. We modified the Warden procedure by using a right atrial auricular flap to decrease the occurrence of these complications. Methods: Between February 2005 and July 2012, 10 consecutive patients underwent a modified Warden procedure to correct PAPVC. The median patient age was 5.7 years. Eight patients (80%) had an atrial septal defect. To surgically correct the PAPVC, we made a U-shaped incision on the right atrial appendage and sutured the flap to the posterior wall of the SVC. The anterior wall was reconstructed with various patch materials. Results: No early or late deaths occurred, nor did any patient require early or late reoperation for SVC or pulmonary venous obstruction. No new arrhythmias appeared during follow-up, which was complete in all patients (mean, 29.5 months). Conclusion: Our modification of the Warden procedure seems to be effective and safe. This technique may lower the risk of SVC obstruction, pulmonary venous obstruction, and sinus dysfunction.

• Journal of Chest Surgery
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• v.12 no.2
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• pp.140-144
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• 1979

This is a report of a case of superior vena caval syndrome due to idiopathic mediastinal fibrosis, which was surgically treated. The patient was 35-year-old Korean male who progressively complained shortness of breath about for 40 days prior to operation. Phlebogram of SVC showed indentation of SVC at the site of cavoatrial junction. The operation was performed under impression of bronchogenic cancer of right hilum. After thoracotomy, it was found a irregular mass in the mediastinum at the level of cavoatrial junction, which was developed to surrounding with SVC, pericardium, trachea and bronchus and they fixed together to immobile. Bypass graft between SVC and right atrial appendage was performed using a pericardial roll tube This is a report of a case of superior vena caval syndrome due to idiopathic mediastinal fibrosis, which was surgically treated. The patient was 35-year-old Korean male who progressively complained shortness of breath about for 40 days prior to operation. Phlebogram of SVC showed indentation of SVC at the site of cavoatrial junction. The operation was performed under impression of bronchogenic cancer of right hilum. After thoracotomy, it was found a irregular mass in the mediastinum at the level of cavoatrial junction, which was developed to surrounding with SVC, pericardium, trachea and bronchus and they fixed together to immobile. Bypass graft between SVC and right atrial appendage was performed using a pericardial roll tube [$1.3{\times}5$ cm]. After that SVC was decompressed very well. SVC pressure was markedly reduced from 32 cm $H_2O$ in preoperative to 21 cm $H_2O$in postoperative. Mediastinal fibrosis was confirmed by histopathological examination postoperatively. The postoperative course was uneventful.

• Journal of Chest Surgery
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• v.53 no.3
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• pp.127-131
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• 2020

Background: This study was conducted to evaluate the safety and efficacy of left atrial appendage (LAA) excision using a vascular stapler. Methods: Fifty consecutive patients (mean age, 68±9 years) who underwent LAA excision using a vascular stapler during concomitant cardiac surgery were enrolled. In all patients, the excision site was evaluated using computed tomography at a median of 7 days (interquartile range, 5-13.3 days) postoperatively. The safety endpoint of this study was the occurrence of LAA excision-related events, which were defined as bleeding from the excision site that required reinforcement sutures or reoperation due to excision site bleeding. The efficacy endpoint was LAA excision failure, which was defined as a remnant LAA (a stump >1 cm in maximum length) or extravasation of radiocontrast dye. Results: LAAs were excised using 60- and 45-mm vascular staplers in 49 patients and 1 patient, respectively. Reinforcement sutures were needed in 4 patients due to staple-line bleeding and in 4 patients due to bleeding of the surrounding tissues. No patient underwent reoperation due to staple-related bleeding. A remnant LAA was observed in 2 patients, while extravasation of radiocontrast dye was not observed in any patients. Conclusion: LAA excision using a vascular stapler may be an effective technique for LAA exclusion. Delicate handling of the stapler device and LA tissue is required to prevent procedure-related complications.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.208-210
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• 1999

Three species belong to the genus Laboulbenia were collected on Carabidae (Coleoptera) and Harpalidae (Coleoptera) from several regions of Korea. Laboulbenia anoplogenii Thaxter was collected from Stenolophus quinquepustulatus Widemann. The characters of this species are the fourth layer of receptacle consisted of two or three cells and the distal end of its posterior cell projecting upward. The thalli were produced on posterior and anterior legs of the hosts. Laboulbenia habui Terada was collected from Chlaenius variicornis Bates. This species is characterized by the basal cells of the secondary appendage composed of short-cylindrical cells, arranged alternately on a double row. The thalli were produced from the elytra and anterior abdomen of the hosts. Laboulbenia pallida Thaxter was collected from Anisodactylus signatus Panzer. This species is distinguished from other related species by the rounded tip of perithecium and the outer appendage branched on the basal cell. The thalli were produced on the posterior elytra of the hosts.