• Journal of Chest Surgery
• /
• v.34 no.4
• /
• pp.345-350
• /
• 2001

배경: 항부정맥 술식으로서의 메이스 술식은 우수한 동율동 전환율을 보고 있으나, 술식의 복잡성과 상대적으로 긴 수술 시간 등으로 모든 환자들에게 적용할 수는 없기에, 일부 환자군에서 보다 간단한 항부정맥술인 폐정맥 분리술을 시행 받은 환자들을 대상으로 동율동 전환율 등의 수술 성적과 위험 인자 등에 대해 알아보고자한다. 대상 및 방법: 1995년 10월부터 1999년 2월까지, 폐정맥 분리술을 시행받은 96명의 환자들을 대상으로 후향적 연구를 시행하였다. 남자가 37명(38.5%), 여자가 59명(61.5%) 이었고, 평균 연령은 46.9$\pm$11.6세 이었다. 승모판 협착 환자가 50명(52.1%), 폐쇄 부전이 24명(25%), 협착과 폐쇄부전이 같이 있었던 경우가 22명(22.9%)이었다. 판막 술식과 폐정맥 분리술을 시행하고 좌심방이 제거술을 시행하였다. 모든 환자들은 술 후 6개월 내지 1년 이내에 외래에서 심전도와 심초음파를 시행받았다. 평균 추적 관찰 기간은 25.9$\pm$11.5개월 이었다. 술 후 최근 추적일까지 동율동으로 전환된 군과 안된 군으로 나누어 분석을 하였다. 결과: 조기 성적으로는 사망이 3명(3.1%), 술 후 6개월 이내의 추적관찰 유실이 2명(2.1%) 이었다. 조기 합병증으로 재수술이 필요 했던 출혈이 4례, 심폐바이패스 이탈 실패오 심실보조장치 등의 삽입이필요했던 경우가 1례, 뇌혈관질환 1례, 심근경색이 1례 등이 있었다. 만기 합병증으로는 동기능 부전 증후군으로 영구 심박동기를 삽입한 경우가 1례, 일시적인 뇌경색 1례 있었고 다른 판막과 연관된 합병증은 없었다. 동율동 전환 환자 수는 75명(82%)이었다. 동율동으로의 전환이 어려운 위험인자로 50세로 이상의 연령(p=0.03), 65mm 이상의 좌심방 크기(p=0.03), 동반 우심 술식 시행(p=0.02)등이 있었다 결론: 승모판 질환을 동반한 심방 세동 환자에서 폐정맥 분리술을 시행하여 만족할 만한 동율동 전환율을 얻을 수 있었다.

• Proceedings of the Korean Society for Bioinformatics Conference
• /
• 2004.11a
• /
• pp.57-63
• /
• 2004

본 연구에서는 3차원 심근조직에서의 회귀성파동에 대한 수치적 해석결과를 제시한다. 심근 조직에서의 회귀성파동은 심실세동(ventricular fibrillation)의 원인으로 지목되고 있으며 심근세포 이온채널 또는 전기전도시스템 등과 같은 여러 가지 요소들이 관련된 복합적 현상으로 생각되고 있다. 지금까지 이에 관한 많은 연구가 전기생리학적 모델을 이용하여 이루어진바 있으며, 주로 동물 심근세포모델에 기반으로 균일한 2차원 또는 3차원 모델에서의 전기전도 현상 해석을 한 바 있다. 그러나 실제 심장조직의 경우, 두께를 가진 3차원적 형상을 지니고 있으며 층을 따라서 전기생리학적으로 상이한 특성을 가진 세포들로 구성된다. 즉 심근은 층을 가로질러 Epi-cardiac, mid-cardiac, endo-cardiac cell들로 구성되며 각기 다른 APD(action potential duration)을 가지고 있다. 따라서 본 연구에서는 이러한 세가지 종류의 인체 심근세포모델을 사용한 3차원 심근조직에서의 활동전위 전도현상에 대한 결과를 제시한다. 이를 위하여 기존의 인체 3가지 종류의 심근세포 모델을 구현하여 그 타당성을 검토한다. 그리고 이를 바탕으로 3차원 조직모델을 구현하는데, simplified bidomain방법을 사용하였다. 3차원 공간상에서 심근세포에 의한 활동전위 전달현상을 해석하기 위하여 유한요소법을 도입한다. 최종적으로는 3가지의 심근세포층을 가진 3차원 심근조직을 구성하고, 여기에 회귀성 파동을 유도한다. 그리고 단일층으로 이루어진 3차원조직에서의 결과와 비교 분석하여 다세포층에 의한 불균일 효과를 분석하였다.

• Journal of Chest Surgery
• /
• v.30 no.8
• /
• pp.823-826
• /
• 1997

Myocardial abscess usually occurs as a complication of infective endocarditis or overwhelming septicemia. Coronary artery occlusion caused by myocardial abscess has been rarely reported. A 61-year-old man presented with fever and chill that developed 6 weeks prior to admission. He had a history of cardiopulmonary resuscitation for ventricular fibrillation and cardiac arrest 4 weeks prior to admission. Echocardiography showed a 3xfcm sized mass in the area of the right atrioventricular groove and coronary angiography showed complete occlusion of the proximal right coronary artery. Under the diagnosis of myocardial infarction complicating myocardial abscess, debridement of abscess and coronary artery bypass grafting with right internal mammary artery to distal right coronary artery was performed. Culture from the abscess cavity demonstrated Salmonella arizona.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.54 no.4
• /
• pp.274-283
• /
• 2005

Coronary Perfusion Pressure(CPP) is known for the most important parameter related to the Return of Spontaneous Circulation (ROSC), however, clinically measuring CPP is difficult either invasive or non-invaisive method. En this paper, we analyze the correlation between the extracted parameter from VF ECG wave and the CPP with the statistical method, and predict CPP value using the extracted parameters within significance level. the extracted parameters are median frequency(MF), peak frequency(PF), average segment amplitude(ASA), MSA(maximum segment amplitude), Two parameters, MF, and ASA are selected in order to predict CPP value with general regression neural network, and then we evaluated the agreement statistics between the simulated CPP and the measured CPP. In conclusion, the mean and variance of the difference between the simulated CPP and the measured CPP are 8.9716±1.3526 mmHg, and standard deviation 6.4815 mmHg with one hundred-times training and test results. the simulated CPP and the measured CPP are agreed with the overall accuracy $90.68\%$ and kappa coefficient $81.14\%$ as a discriminant parameter of ROSC.

• Journal of Chest Surgery
• /
• v.31 no.4
• /
• pp.398-401
• /
• 1998

A 56-year-old female with a permanent unipolar pacing(VVI) system underwent elective coronary bypass surgery and mitral valve replacement. Because the unipolar sensing is subject to considerable nonmyocardial electrical noise, the pacing function may be disturbed by the use of electrocautery. Temporary atrial and ventricular bipolar epicardial leads and external generator were used for maintaining A-V sequential pacing during the use of electrocautery. Before aortic cross-clamp was released after cardiac operation, regular cardiac rhythm could spontaneously be resumed with an integrated cardioplegic strategy, avoiding the use of defibrillator

• Journal of Chest Surgery
• /
• v.35 no.6
• /
• pp.463-466
• /
• 2002

We present a case of coronary artery fistula originating from the proximal left anterior descending artery draining into the main pulmonary artery, which was associated with atrial septal defect. The patient was a 56 year old male who was admitted for exertional dyspnea and abdominal distension. Echocardiogram and selective coronary arteriogram revealed a atrial septal defect and fistulous connection. The patient underwent surgery under the cardiopulmonary bypass with fibrillating heart. The pericardial patch closure of atrial septal defect and internal obliteration of the fistula termination site in the main pulmonary artery were performed. Postoperative hospital courses were uneventful without any specific complication and the patient was discharged without problem.

• The Korean Journal of Emergency Medical Services
• /
• v.20 no.2
• /
• pp.7-19
• /
• 2016

Purpose: To investigate the effect of early hypothermia on post-resuscitation myocardial recovery and survival time after cardiac arrest and resuscitation in a rat model of myocardial infarction(MI). Methods: Thoracotomies were performed in 10 male Sprague Dawley rats weighing 450-455g. Myocardial infarction was induced by ligation of the left anterior descending coronary artery. Ninety minutes after arterial ligation, ventricular fibrillation was induced, cardiopulmonary resuscitation was subsequently performed before defibrillation was attempted. Animals were randomized to control group and experimental group(acute MI-normothermia)($32^{\circ}C$ for 4 hours). Duration of survival was recorded. Myocardial functions, including cardiac output, left ventricular ejection fraction, and myocardial performance index were measured using echocardiography. Results: Myocardial function was significantly better in hypothermia group than the control group during the first 4 hours post-resuscitation. The survival time of the experimental group was greater than that of the control group(p<.050). Conclusion: This study suggests that early hypothermia can attenuate post-resuscitation myocardial dysfunction after acute myocardial function, and may be a useful strategy in post-resuscitation care.

• Journal of Yeungnam Medical Science
• /
• v.6 no.1
• /
• pp.99-107
• /
• 1989

24-hour ambulatory ECG monitoring has been examined for the evaluation of heart rate and longest pause in 34 patients with chronic atrial fibrillation(20 patients treated with digoxin and 14 patients without treatment). Following results were obtained : 1. In 34 patients, the mean of average heart rates was $75.7{\pm}13.8$/minute, fastest heart rates $148.0{\pm}32.4$/minute, slowest heart rates $48.1{\pm}8.4$/minute, difference between fastest and slowest heart rates in individual patients $99.9{\pm}29.0$/minute and longest pauses $2.95{\pm}1.06$seconds. The longest pauses of more than 4.0 seconds occurred in 4 of the 34 patients and made an exeption of comparison groups. 2. In 27 of the 34 patients, ventricular premature contractures were developed and in 11 of 27, mainly occured less than 100/24 hours and aberrant conduction occurred in all patients. 3. In 20 patients treated with digoxin(0.25mg/day), the mean of average heart rates was $78.4{\pm}13.7$/minute, fastest heart rates $152.5{\pm}33.1$/minute, slowest heart rates $48.9{\pm}8.5$/minute, difference between fastest and slowest heart rates in individual patients $103.6{\pm}31.7$/minute and longest pauses $2.55{\pm}0.50$seconds. 4. In 10 patients without treatment, the mean of average heart rates was $78.0{\pm}10.7$/minute, fastest heart rates $154.5{\pm}26.8$/minute, slowest heart rates $50.6{\pm}7.1$/minute, difference between fastest and slowest heart rates in individual patients $103.9{\pm}22.2$/minute and longest pauses $2.66{\pm}0.39$seconds. 5. The difference of heart rates and longest pauses between patients with treatment and without treatment were statistically not significant(P>0.05). In summary, authors seemed to consider that 24-hour ambulatory ECG was useful and safe method for clinical evaluation of patients with chronic atrial fibrillation.

• Journal of Chest Surgery
• /
• v.29 no.12
• /
• pp.1342-1346
• /
• 1996

A right thoracotomy was used for the reoperation or mitral valve of 15 patients who had previously undergone a cardiac operation through a median sternotomy. In our experience. this approach provided dn excellent exposure of the nlitral valve and easy cannulations of both cavie with minimal dissection, ilvoiding any damage of cardiac and major vessels during re-sternotomy Arterial cannulation was performed in the ascending aorta in 13 patients And in the femoral artery in 2 patients. In earlier cases, venous cannulation was done in the SVC And IVC through the right atrium and snared. In later cases, this could be done without snaginly of both cavae or by placing a silgle light-angled catheter into the right atrium. Crystalloid cardioplegic solution was infused for myocardial protection. Hypothermia was controlled at 20\ulcorner$25^{\circ}C$. For defibrillation, internal paddles were used In one patient while sterilized external paddles were used in 10 patients. In the remaining four patients. however. the heart beat spontaneously The respirator could be weaned within 48 hours alter the operation and no pulmonary complication was observed. One out of the 15 patients expired due to sudden attack of ventricular tarchycardid developed ten days after the operation, but the rest of the patients were discharged with good condition.

• Journal of Biomedical Engineering Research
• /
• v.38 no.3
• /
• pp.123-128
• /
• 2017

Background and aims: The KCNQ1 S140G mutation involved in $I_{ks}$ channel is a typical gene mutation affecting atrial fibrillation. However, despite the possibility that the S140G gene mutation may affect not only atrial but also ventricular action potential shape and ventricular responses, there is a lack of research on the relationship between this mutation and ventricular fibrillation. Therefore, in this study, we analyzed the correlation and the influence of the KCNQ1 S140G mutant gene on ventricular fibrillation through computer simulation studies. Method: This study simulated a 3-dimensional ventricular model of the wild type(WT) and the S140G mutant conditions. It was performed by dividing into normal sinus rhythm simulation and reentrant wave propagation simulation. For the sinus rhythm, a ventricular model with Purkinje fiber was used. For the reentrant propagation simulation, a ventricular model was used to confirm the occurrence of spiral wave using S1-S2 protocol. Results: The result showed that 41% shortening of action potential duration(APD) was observed due to augmented $I_{ks}$ current in S140G mutation group. The shortened APD contributed to reduce wavelength 39% in sinus rhythm simulation. The shortened wavelength in cardiac tissue allowed re-entrant circuits to form and increased the probability of sustaining ventricular fibrillation, while ventricular electrical propagation with normal wavelength(20.8 cm in wild type) are unlikely to initiate re-entry. Conclusion: In conclusion, KCNQ1 S140G mutation can reduce the threshold of the re-entrant wave substrate in ventricular cells, increasing the spatial vulnerability of tissue and the sensitivity of the fibrillation. That is, S140G mutation can induce ventricular fibrillation easily. It means that S140G mutant can increase the risk of arrhythmias such as cardiac arrest due to heart failure.