• Journal of Chest Surgery
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• v.50 no.4
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• pp.235-241
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• 2017

Background: The Ross/Ross-Konno procedure is considered a good option for irreparable aortic valve disease in pediatric patients because of its hemodynamic performance and potential for growth of the pulmonary autograft. This study is a review of the long-term results of our 20-year experience with the Ross and Ross-Konno operations in a single institution. Methods: Between June 1995 and January 2016, 16 consecutive patients (mean age, $6.0{\pm}5.9years$; range, 16 days to 17.4 years) underwent either a Ross operation (n=9) or a Ross-Konno operation (n=7). The study included 12 males and 4 females, with a median follow-up period of 47 months (range, 6 to 256 months). Results: There were no cases of in-hospital or late mortality. Six reoperations were performed in 5 patients. Four patients underwent right ventricular-pulmonary artery (RV-PA) conduit replacement. Two patients underwent concomitant replacement of the pulmonary autograft and RV-PA conduit 10 years and 8 years after the Ross operation, respectively. The rate of freedom from adverse outcomes of the pulmonary autograft was 88% and 70% at 5 and 10 years, respectively. The rate of freedom from valve-related reoperations was 79% and 63% at 5 and 10 years, respectively. Conclusion: Pulmonary autografts demonstrated good durability with low mortality. The Ross/Ross-Konno procedure is a good option that can be performed safely in pediatric patients with aortic valve disease, even in a small-volume center.

• Journal of Chest Surgery
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• v.33 no.9
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• pp.744-747
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• 2000

Pulmonic autograft replacement of the aortic valve(Ross procedure) has been to have potential for growth in children, no complication of antiocagulation, and enhanced durability. Therefore, Ross operation is indicated in the young, in patients with an active life style, and when anticoagulation is contraindicated. However, late autograft valve has occurrd more frequently in patients with significant size discrepancy between the pulmonay valve annulus and the aortic valve annulus. In order to resolve this problem, we performed aortic annuloplasty with Duran ring for more accurate and strong reinforcement. We report a case using the Duran ring as a method of aortic annuloplasty during Ross procedure.

• Journal of Chest Surgery
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• v.38 no.5 s.250
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• pp.382-384
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• 2005

Background: It is very difficult to choose the ideal valved conduit used in right ventricle outflow reconstruction in child. We can use the cryopreserved homograft but there is a limit of application because of its difficulties in the size matching and supply capacity. The $Shelhigh^{(R)}$porcine-valved conduit is commercially available and used as an alternative choice in these days. We report two cases of early Shelhigh conduit failure in right ventricular outflow tract after Ross operation in congenital aortic stenosis.

• Journal of Chest Surgery
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• v.29 no.8
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• pp.822-827
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• 1996

Ross procedure is an ideal operative modality for diseased aortic valve especially in children, but homogrart for right ventricular outflow tract(RVOT) reconstruction is not easily available in Korea. We tried to perform REV procedure for RVOT reconstruction in 10 young piglets(15.3 $\pm$ 1.3 kg) In an attempt to e clude the use of homograft in Ross operation. 3 of them survived after operation and raised till adult pig(about 70 kg), then examined their pulmonary arteries and hearts. Without any stenotic residues in the great arteries, we only found the deformed monocusp patch with severe calcification, which deprived the adequate valve function, but kept the pig growing normally We are sure that this operative modality (REV + Ross procedure) could be extendedly applied to the diseased human aortic valve, but we need to develope the anti-calcification method for the heterograft patch.

• Journal of Chest Surgery
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• v.32 no.3
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• pp.303-306
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• 1999

This is a genuine case report of the Ross operation without the use of homografts or heterografts in reconstruction of the right ventricular outflow tract. A 8-year-old boy with congenital aortic stenosis underwent aortic valve replacement with a pulmonary autograft and right ventricular outflow tract reconstruction with a pericardial conduit bearing autologous aortic monocusp. The postoperative echocardiography and cardiac angiography revealed good ventricular function and competent neoaortic valve. He has been followed up for 19 months.

• Journal of Chest Surgery
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• v.42 no.3
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• pp.305-310
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• 2009

Background: The Ross procedure is known as a good surgical option for a young age group with aortic valve problems, but few reports on the Ross procedure are available in the Korean literature. This study is a review of our midterm results of 10 year experience with the pediatric Ross operation in Asan Medical Center. Material and Method: From March 1997 to October 2008, eighteen patients who were aged less than 16 years underwent the Ross procedure. There were 11 males and 7 females. The patients median age was 8.5 years (range: $0.5\sim14.0$). The aortic valve pathophysiology was 6 patients with aortic insufficiency, 4 patients with aortic stenosis, 7 patients with mixed aortic stenoinsufficiencey and 1 patient with infective endocarditis. The valve morphology was bicuspid in 11 and tricuspid in 7. All the patients were operated on with the root replacement technique. All the pumonic valves were replaced with an allograft except for one pericardial monocusp valve. The mean follow up duration was 52.8 months (range: 5.8$\sim$138.2 months). We reviewed the echocardiographic data with focusing on the, auto-graft dysfunction and reoperation. Result: There was no hospital mortality and late mortality. According to the last echocardiographic data, 2 autografts showed aortic regurgitation grade 2, 4 autografts showed aortic regurgitation grade 1 and the others were less than trivial. Reoperation of the pulmonic position conduit was performed 4 times in three patients. The rate of freedom from reoperation at 5 years was 72.2%. On the serial follow up, the Z-values of the aortic annulus/aortic sinus were changed from $1.6{\pm}1.7/0.9{\pm}1.7$ at preoperation to $1.8{\pm}1.6$(p=0.64)/$2.2{\pm}0.9$ (p=0.01) at the last follow-up. There was no significant relation between the growth of the neoaortic root and neoaortic insufficiency. Conclusion: Our midterm results of the Ross procedure in pediatric patients showed good autograft function and growth potential. Vet reoperation due to allograft dysfunction was a major concern.

• Journal of Chest Surgery
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• v.40 no.1 s.270
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• pp.17-24
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• 2007

Background: The aim of this study is to assess the clinical results of various procedures in congenital aortic stenosis. Material and Method: From August 1987 to June 2004, 53 patients of congenital aortic stenosis underwent procedures such as percutaneous balloon valvuloplasty, aortic valvuloplasty, Ross procedure, and aortic valve replacement. The mean age of initial procedures was $8.2{\pm}6.0$ years. Percutaneous balloon valvuloplasty was peformed in sixteen patients, aortic valvulopiasty in thirty two patients, Ross procedure in nineteen patients, and aortic valve replacement in fourteen patients. The mean follow duration was $80.6{\pm}60\;(0{\sim}207)$ months. Result: There was 15.1% (8/53) of early mortality and no late mortality. The six patients with critical aortic stenosis were died of left ventricular dysfunction in early series (before 1 year; 4 cases) and two patients died after the Ross procedure and aortic valve replacement respectively. After percutaneous balloon valvuloplasty, most patients needed reoperations (14/16). Thirteen patients needed reoperation, after aortic valvuloplasty. After Ross procedure, two patients needed reoperation due to aortic regurgitation caused by progressive aortic root dilatation. The actuarial survival rate after Ross procedure at 7 years was 90.5%. Conclusion: In young children before the age of one, percutaneous balloon valvuloplasty was considered as :he safe initial palliative procedure. But children over one year-old, aortic valvuloplasty were the effective procedure. Ross procedure can be preformed safely with good results.

• Journal of Chest Surgery
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• v.31 no.10
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• pp.1009-1013
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• 1998

Bacterial endocarditis of the native aortic valve is associated with significant morbidity and mortality despite aggressive medical and surgical treatment, especially when perivalvular tissue was invaded and destructed. The pulmonary autograft is full viable and immune compatible tissue. This paper describes successful Ross operation as total root replacement in 38 years old native valve endocarditis patient with aortic root abscess.

• Journal of Chest Surgery
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• v.35 no.4
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• pp.274-282
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• 2002

Background: Paravalvular leakage or false aneurysm developed after isolated aortic valve replacement(AVR) for aortic regurgitation(AR) associated with Behcet's disease is one of the most serious complications, and requires subsequent reoperations. We describe the surgical result of homograft aortic root replacement(ARR) for AR associated with Behcet's disease. Material and Method: From January 1992 to December 2001, 6 patients with AR associated with Behcet's disease underwent 7 ARR with homograft and 1 Ross operation. Five patients were male and one was female. The grafts used for ARR were 5 aortic and 2 pulmonic homografts. Ages at operation ranged from 27 to 51 years(mean, 37$\pm$9 years). Two patients underwent ARR with aortic homograft at the first operation. In the remaining 4 patients, ARR using a homograft was performed for paravalvular leakage that developed after AVR, and the mean interval from AVR to ARR was 21 $\pm$29 months(range, 5 to 73.3 moths, median, 7.6 months). Result: There was no early death. All patients were followed up for an average of 18.9$\pm$24.0 months(range, 1.9 to 68.9 months, median, 8.4 months). Two of 4patients who had undergone ARR after AVR required subsequent reoperations for false aneurysm of the ascending aorta and failure of pulmonary homograft. One patient underwent re-replacement of the aortic root, ascending aorta and partial aortic arch with an aortic homograft, the other underwent Ross operation. Conclusion: This study suggests that aortic root replacement using a homograft in aortic regurgitation with Behcet's disease may provide good clinical results and decrease the incidence of paravalvular leakage or false aneurysm after aortic valve replacement. However, the adequate perioperative management and complete removal of the inflarrunatory tissue at operation were also important for the good long-term results.

• Transactions of the KSME C: Technology and Education
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• v.3 no.2
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• pp.97-106
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• 2015

Flexible structures are often important components of mechanical assemblies in motion. A flexible structure sometimes must go through assembly steps that cause it to be in a pre-stressed condition when in the starting position for operation. A virtual prototype of the assembly must also bring the model of the flexible structure into the same pre-stressed condition in order to obtain accurate simulation results. This case study is presented regarding the simulation of a constant velocity joint, with a focus on the flexible boot. The case study demonstrates that careful definition of the initial conditions of the boot and flexible body contacts yields high-fidelity simulation results.