• Proceedings of the KSME Conference
• /
• 2007.05b
• /
• pp.2947-2950
• /
• 2007

A 3D human ventricular model is proposed to simulate an integrative analysis of heart physiology and blood hemodynamics. This consists of the models of electrophysiology of human cells, electric wave propagation of tissue, heart solid mechanics, and 3D blood hemodynamics. The 3D geometry of human heart is discretized to a finite element mesh for the simulation of electric wave propagation and mechanics of heart. In cellular level, excitations by action potential are simulated using the existing human model. Then the contraction mechanics of a whole cell is incorporated to the excitation model. The excitation propagation to ventricular cells are transiently computed in the 3D cardiac tissue using a mono-domain method of electric wave propagation in cardiac tissue. Blood hemodynamics in heart is also considered and incorporated with muscle contraction. We use a PISO type finite element method to simulate the blood hemodynmaics in the human ventricular model.

• Journal of Chest Surgery
• /
• v.39 no.5 s.262
• /
• pp.399-402
• /
• 2006

Stent thrombosis is a rare complication after percutaneous coronary intervention (PCI), but it might be related to fatal outcomes. We report a case of patient who suffered from acute myocardial infarction complicated with cardiogenic shock and ventricular tachycardia caused by stent thrombosis and successfully resuscitated by percutaneous cardiopulmonary bypass support.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2013.07a
• /
• pp.355-356
• /
• 2013

심장의 활동을 전기적 변위로 표현되는 심전도 신호는 심장병 진단에 중요한 임상적 파라미터들을 제공한다. 특히 심전도 신호에서 P, QRS Complex,, T 특징점들로 대표되는 파형 변곡점들의 시간상 위치와 크기 및 형태학적 모양은 심장의 이상 리듬을 나타내는 부정맥여부를 검출하는데 핵심적인 역할을 한다. 본 연구에서는 특히 QRS complex 구간에 대한 첨도치의 연산 해석을 통하여 정상적인 심전도 리듬과 심실조기수축 부정맥 리듬을 구분하는 방법을 제시하고 또한 스마트폰을 기반으로 하는 심전도 모니터링 시스템에 적용하고자 하였다.

• Proceedings of the IEEK Conference
• /
• 2009.05a
• /
• pp.393-395
• /
• 2009

심장의 활성 근육의 움직임에 의하여 발생되는 전기적 변화량을 나타내는 심전도는 부정맥 또는 허혈성 심장질환을 진단하는데 널리 활용되고 있다. 특히 심실빈맥(Ventricular Tachycardia) 또는 심실세동(Ventricular Fibrillation)과 같이 치명적인 심장리듬이 발생하기 이전에, 심실조기수축(Ventricular Premature Contraction)을 검출하여 생명을 위협할 수 있는 부정맥을 조기에 진단할 수 있는 연구들이 일부 진행되고 있다. 이에 따라서 본 연구에서는 심전도 신호의 R-R 간격 정보와 R-peak 정보의 진위성을 판단하여 PVC 부정맥 패턴뿐만 아니라 PVC 파형이 연속적으로 진행되는 PVC-RUNs을 효율적으로 검출할 수 있는 부정맥 진단 알고리즘을 제안하고자 하였다.

• Journal of Chest Surgery
• /
• v.39 no.9 s.266
• /
• pp.702-705
• /
• 2006

Severe left ventricular dysfunction after relief of massive pericardial effusion has been rarely reported. Interventricular volume mismatch, acute distention of the cardiac chambers and interplay of autonomic none system are believed to be the possible causes for ventricular dysfunction. Presenting two patients who had marked decrease in global ventricular systolic function after relief of pericardial tamponade by subxyphoid pericardial window, we recommend gradual removal of pericardial fluid under hemodynamic monitoring, especially in patient with postcardiotomy tamponade.

• Journal of Chest Surgery
• /
• v.35 no.2
• /
• pp.133-136
• /
• 2002

A 28 year-old male who had received Konno procedure twelve years ago with 23mmmechanical aortic valve and bovine pericardium with which his small aortic annulus, ventricular septum and right ventricular outflow tract had been enlarged was transferred due to sudden congestive heart failure. There were perforations on aortic and interventricular portion of bovine pericardial patch above and below the aortic valve, respectively, which was calcified and denaturated severely. The perforations seemed to be attributed to the cracks, resulting from mobility of mechanical aortic valvc itself and stiffness of calcified and denaturated bovine patch. We performed a redo Konno procedure applying PTFE patch.

• Journal of Chest Surgery
• /
• v.30 no.4
• /
• pp.419-422
• /
• 1997

In small children with left ventricular outflow tract obstruction, a few methods of surgical treatment could be considrred. The pulmonary autogrart provides a promising options for aortic valve replacement as part of the aortoventriculoplasty procedure in children. We report a successfully treated congenital aortic stcnoinsufricicncy with severe left ventricular dysfunction in an early infant with the aortoventriculoplasty using thc pulmonary autograft (the Ross-Konno procedure).

• Journal of Chest Surgery
• /
• v.37 no.11
• /
• pp.933-936
• /
• 2004

Intravenous leiomyomatosis is a rare disease entity of benign smooth muscle invading into the lumen of veins. We describe a case of intravenous leiomyomatosis originating from the uterus, growing in the inferior vena cava, and extending into the right ventricle association with multiple pulmonary metastasis. A 53-year-old woman with chest discomfort and several times attacks of syncope was treated at our hospital. The tumor was successfully removed with moderate hypothermic cardiopulmonary bypass after total hysterectomy with a bilateral salphingo-oophorectomy, and multiple pulmonary metastasis under simultaneous sternotomy and laparotomy was confirmed.

• Journal of Chest Surgery
• /
• v.32 no.3
• /
• pp.303-306
• /
• 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
• /
• v.39 no.8 s.265
• /
• pp.588-597
• /
• 2006

Background: The surgical repair of a tetralogy of Fallot (TOF) has been performed successfully with a favorable early and late outcome. However, the later development of pulmonary regurgitation and stenosis remains a problem. The development of pulmonary regurgitation and stenosis may be changed by the size of right ventricular outflow tract (RVOT) reconstruction at the initial total correction. Hence, it is necessary to investigate the ideal size of RVOT reconstruction. Material and Method: This prospective study was carried out to determine how a surgical strategy and the RVOT size affect the occurrence of pulmonary regurgitation and stenosis. From January 2002 to December 2004, 62 patients underwent the TOF total correction. The RVOT size (diameter of pulmonary valve annulus) of each case was measured after the RVOT reconstruction and converted to a Z value. A pre-scheduled follow up (at discharge, 6 months, 1 year, 2 years and 3 years) was carried out by echocardiography to evaluate the level of pulmonary regurgitation and stenosis. Result: The patients were divided to two groups (transannular group n=12, nontransannular group n=50) according to the method of a RVOT reconstruction. The Z value of RVOT=iameter of pulmonary valve annulus) (transannular group -1, $range\;-3.6{\sim}-0.8;$ nontransannular group -2.1, $range\;-5.2{\sim}-1.5)$ and the average pRV/LV after surgery ${(transannular group 0.44{\pm}0.09,\;nontransannular group\;0.42{\pm}0.09)}$ did not show any significant difference between two groups. The occurrence of pulmonary regurgitation above a moderate degree was more frequent in the transannular group (p<0.01). In nontransannular group, the development of pulmonary regurgitation more than moderate degree occurred to the patients with larger RVOT size (Z value>0, p<0.02) and the progressing pulmonary stenosis more than mild to moderate degree developed in the patients with smaller RVOT size (Z value<-1.5, p<0.05). A moderate degree of pulmonary stenosis developed for 4 nontransannular patients. Three underwent additional surgery and one underwent a balloon valvuloplasty. Their Z value of RVOT were -3.8, -3.8 -2.9, -1.8, respectively. Conclusion: When carring out a TOF total correction, transannular RVOT reconstruction group has significantly more pulmonary regurgitation. In the nontransannular RVOT reconstruction. the size of the RVOT should be maintained from Z value -1.5 to 0. If the Z value is less than -1.5, we should follow up carefully for the possibility of pulmonary stenosis.