• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1992년도 춘계학술대회
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• pp.27-47
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• 1992

Engineers have developed new instruments that aid in diagnosis and therapy Ultrasonic imaging has provided a nondamaging method of imaging internal organs. A complex transducer emits ultrasonic waves at many angles and reconstructs a map of internal anatomy and also velocities of blood in vessels. Fast computed tomography permits reconstruction of the 3-dimensional anatomy and perfusion of the heart at 20-Hz rates. Positron emission tomography uses certain isotopes that produce positrons that react with electrons to simultaneously emit two gamma rays in opposite directions. It locates the region of origin by using a ring of discrete scintillation detectors, each in electronic coincidence with an opposing detector. In magnetic resonance imaging, the patient is placed in a very strong magnetic field. The precessing of the hydrogen atoms is perturbed by an interrogating field to yield two-dimensional images of soft tissue having exceptional clarity. As an alternative to radiology image processing, film archiving, and retrieval, picture archiving and communication systems (PACS) are being implemented. Images from computed radiography, magnetic resonance imaging (MRI), nuclear medicine, and ultrasound are digitized, transmitted, and stored in computers for retrieval at distributed work stations. In electrical impedance tomography, electrodes are placed around the thorax. 50-kHz current is injected between two electrodes and voltages are measured on all other electrodes. A computer processes the data to yield an image of the resistivity of a 2-dimensional slice of the thorax. During fetal monitoring, a corkscrew electrode is screwed into the fetal scalp to measure the fetal electrocardiogram. Correlations with uterine contractions yield information on the status of the fetus during delivery To measure cardiac output by thermodilution, cold saline is injected into the right atrium. A thermistor in the right pulmonary artery yields temperature measurements, from which we can calculate cardiac output. In impedance cardiography, we measure the changes in electrical impedance as the heart ejects blood into the arteries. Motion artifacts are large, so signal averaging is useful during monitoring. An intraarterial blood gas monitoring system permits monitoring in real time. Light is sent down optical fibers inserted into the radial artery, where it is absorbed by dyes, which reemit the light at a different wavelength. The emitted light travels up optical fibers where an external instrument determines O2, CO2, and pH. Therapeutic devices include the electrosurgical unit. A high-frequency electric arc is drawn between the knife and the tissue. The arc cuts and the heat coagulates, thus preventing blood loss. Hyperthermia has demonstrated antitumor effects in patients in whom all conventional modes of therapy have failed. Methods of raising tumor temperature include focused ultrasound, radio-frequency power through needles, or microwaves. When the heart stops pumping, we use the defibrillator to restore normal pumping. A brief, high-current pulse through the heart synchronizes all cardiac fibers to restore normal rhythm. When the cardiac rhythm is too slow, we implant the cardiac pacemaker. An electrode within the heart stimulates the cardiac muscle to contract at the normal rate. When the cardiac valves are narrowed or leak, we implant an artificial valve. Silicone rubber and Teflon are used for biocompatibility. Artificial hearts powered by pneumatic hoses have been implanted in humans. However, the quality of life gradually degrades, and death ensues. When kidney stones develop, lithotripsy is used. A spark creates a pressure wave, which is focused on the stone and fragments it. The pieces pass out normally. When kidneys fail, the blood is cleansed during hemodialysis. Urea passes through a porous membrane to a dialysate bath to lower its concentration in the blood. The blind are able to read by scanning the Optacon with their fingertips. A camera scans letters and converts them to an array of vibrating pins. The deaf are able to hear using a cochlear implant. A microphone detects sound and divides it into frequency bands. 22 electrodes within the cochlea stimulate the acoustic the acoustic nerve to provide sound patterns. For those who have lost muscle function in the limbs, researchers are implanting electrodes to stimulate the muscle. Sensors in the legs and arms feed back signals to a computer that coordinates the stimulators to provide limb motion. For those with high spinal cord injury, a puff and sip switch can control a computer and permit the disabled person operate the computer and communicate with the outside world.

• Journal of Chest Surgery
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• 제42권2호
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• pp.193-200
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• 2009

배경: 기계식 인공 심장판막 치환 수술을 받은 환자들에 있어서 장기간의 경구 항응고제 투여는 반드시 필요하다. 그러나 이러한 환자들에 있어서 혈색전증의 발생을 예방하는 동시에 출혈을 방지하기 위한 적절한 항응고제의 용량에 관해서는 아직까지 논의의 소지가 있다. 저자들은 INR (International Normalized Ratios)을 1.5에서 2.5사이에 두는 낮은 강도 항응혈 관리를 적용하여 장기 추적관찰 결과를 분석하였다. 대상 및 방법: 1992년 1월부터 2002년 12월까지 144명의 단일 심장판막 치환 수술을 받은 환자를 대상으로 하였다. 평균연령은 47.4세였고$(15{\sim}72)$, 대동맥판막 치환수술을 받은 환자는 49명, 승모판막 치환수술을 받은 환자는 95명이었다. 이들의 항응고 수치와 임상 결과를 분석하였다. 환자들은 본원 외래로 $1{\sim}2$개월에 한번씩 임상관찰 추적하고 prothrombin time을 측정하여 INR을 낮은 강도 항응혈 목표치인 1.5와 2.5사이에 유지하려 하였다. 결과: 총 144명의 환자에서 추적관찰 기간은 835.3 환자년(평균 $5.9{\pm}3.5$)이었으며 7,706개의 INR측정치가 평가의 대상이었다 승모판막 치환수술군과 대동맥판막 치환수술군 간에 INR 수치는 유의한 차이를 보였다(p<0.01). 모든 환자의 INR측정 수치의 61.9%가 목표 범위 내에 있었다. 심방세동이 있는 환자는 전체의 30.3%였으며 그들의 INR 측정치$(2.16{\pm}0.23)$는 동율동 환자들의 INR 측정치$(2.03{\pm}0.27)$보다 유의하게 높았다(p<0.01). 혈색전증은 9명의 환자에서 보였으며 1.08%/환자년의 발생율을 보였다. 주요 출혈은 2명의 환자에서 발생하였고 발생율은 0.24%/환자년이었다. 환자의 순응도가 좋을수록 합병증 발생율이 유의하게 낮았다(p=0.000). 결론: 단일 대동맥판막 또는 승모판막 치환술 후 항응혈 치료에서 낮은 강도의 INR 목표범위로도 효과적이고 안전한 항응혈 치료가 가능하다는 것을 시사하며 더 효과적인 항응혈 치료를 위해서는 환자의 순응도를 높여야 될 것으로 사료된다.

• Journal of Chest Surgery
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• 제43권5호
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• pp.475-481
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• 2010

배경: 퇴행성 승모판막역류증으로 승모판막성형술을 받은 환자들 중에서 partial flexible band를 이용한 경우와 complete rigid ring을 이용한 경우의 중기 성적을 비교해 보고자 하였다. 대상 및 방법: 2004년 1월부터 2008년 9월 사이에 단독 승모판막역류증으로 승모판막수술을 받은 112명의 환자 중 퇴행성 질환으로 확진되고, 승모판막성형술 및 승모판막륜 링 삽입술을 시행 받은 71명의 환자(남:여=36:35, $55{\pm}13$세)를 대상으로 하였다. 환자들을 승모판막륜성형술에 partial flexible band를 이용한 I군(43명)과 Complete rigid ring을 이용한 II군(28명)으로 나누어 단기 및 중기 성적을 비교하였다. 두 군 간의 수술 전 특성에는 유의한 차이가 없었다. 추적관찰 기간의 중앙값은 36개월(2~69개월)이었다. 결과: 수술관련 사망은 없었으며, 심방세동(n=7), 저심박출 증후군(n=5)과 같은 수술 관련 합병증의 발생은 두 군 간 발생률의 차이가 없었고, II군에서 만기 사망이 1예 있었다. 4년 승모판막역류재발 자유 생존률은 I군과 II군에서 각각 94.5%와 91.8%였다(p=0.695). 좌심실 구출율은 수술 후 조기($7{\pm}2$일)에는 저하 되었고, 최종 추적관찰 시점($25{\pm}16$개월)에서 회복되었다(p=0.002). 이런 변화 추세는 양군에 차이가 없었다(p=0.905). 재수술은 3명의 환자(I군에서 1예, II군에서 2예, p=0.905)에서 시행되었다. 4년 판막 관련 사건 자유 생존률은 두 군 간에 차이가 없었다(I군 95.2% vs II군 92.6%, p=0.646). 결론: 승모판막륜 성형술에 사용되는 판막륜 링의 종류는 퇴행성 승모판막 역류증에 대한 승모판막 성형술의 중기 임상성적 및 기능결과에는 영향을 주지 않았다.

• Journal of Chest Surgery
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• 제23권2호
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• pp.213-221
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• 1990

We have experienced 62 cases of modified Fontan operations in Seoul Nat’l University Hospital from Apr. 1986 to Jul. 1989, They were 38 males and 24 females, and their age was ranged from 16 months to 15.5 years of age. [mean age : 5.73$\pm$2.99 years] There were 16 operative deaths and 2 late deaths, therefore 29% of overall mortality. Their diagnoses were as follows; 28 single ventricle, 11 tricuspid atresia, 6 DORV with LV hypoplasia, 3 pulmonary atresia with hypoplastic RV, 3 TGA with hypoplastic RV, 3 cor\ulcornerGA with hypoplastic LV and PA, 6 AV canal defects with PA, and 2 others. Low cardiac output and pleural effusion were developed frequently, so we divide 40 patients into some groups to analyze the physiologic and anatomic causes of them. By the degree of the LCO, group A was no LCO[mean amount of inotropics used: 0-5 \ulcornerg/kg/min] with 17 cases, B mild LCO [5-10] with 11, C moderate to severe LCO but alive[>10] with 8, D severe LCO to death with 4 cases. For the pleural effusion, group 1 was to be removed the chest tube within 1 week with 8 cases, group II within 3 weeks with 21 cases, group III beyond 3 weeks with 12 cases. We considered their age, diagnosis, pulmonary artery size[PA index], pulmonary artery abnormality, palliative shunt, systemic ventricular type, pulmonary artery wedge pressure, as preoperative factors, and operative methods, and as postoperative factors, CVP, LAP, arrhythmia, thrombosis, atrioventricular valvular insufficiency, etc. In the view of LCO, pulmonary artery size and PCWP were statistically significant [P<0.05], and arrhythmia, A-V valve insufficiency were inclined to the group C and D Pleural effusion was influenced by the pulmonary artery size, pulmonary artery resistance, PCWP, and CVP significantly. [P<0.05] And arrhythmia, residual shunt, and A-V valvular insufficiency were inclined to group II and III, too. As a results, the followings are to be reminded as the important factors at the care of post-Fontan LCO, and persistent pleural effusion [1] pulmonary artery size, [2] pulmonary artery resistance, [3] PCWP, [4] CVP, [5] arrhythmia, [6] residual shunt, [7]A-V valvular insufficiency.

• 대한핵의학회지
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• 제16권2호
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• pp.29-36
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• 1982

Quantification of the regurgitation amount is important before and after valvular replacement surgery. Until now cardiac catheterization with cineventriculography, echocardiography have been used to measure the regurgitation amount, but also have many limitations. EKG gated cardiac blood pool scan provides a simple, non-invasive -method for quantify the regurgitation amount. By calculating the ratio of left ventricular to right ventricular stroke counts (stroke volume ratio) in gated bood pool scan, we measured the left ventricular regurgitation amount in 28 cases of valvular regurgitation and 25 cases of normal group. 1. Stroke volume ratio was higher in cases of valvular regurgitation $(2.11{\pm}0.58)$ than in cases of normal control $(1.15{\pm}0.31)$. (p<0.01). 2. Stroke volume ratio was classified by regurgitation grade using X-ray cineventriculography. In grades of mild regurgitation $(Grade\;I{\sim}II)$, stroke volume ratio was $2.02{\pm}0.29$, and in grades of severe regurgitation $(Grade\;III{\sim}IV)$, stroke volume ratio was $2.55{\pm}0.34$, so stroke volume ratio was well correlated with the grade of X-ray cineventriculography. 3. Stroke volume ratio was classfied by functional class made in New York Heart Association. In classes of mild regurgitation $(class\;I{\sim}II)$, stroke volume ratio was $2.08{\pm}0.26$, and in classes of severe regurgitation $(class\;III{\sim}IV)$, stroke volume ratio was $2.55{\pm}0.38$, Stroke volume ratio well represented the functional class. 4. After aortic and mitral valve replacement in 28 patients, the stroke volume ratio, decreased from $2.11{\pm}0.58\;to\;1.06{\pm}0.26$. Gated blood pool scan provides a noninvasive method of qnantifying valvular regurgitation and assessing the result of surgical interventions.

• Clinical and Experimental Pediatrics
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• 제46권6호
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• pp.591-596
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• 2003

목 적 : 3개월 이하 영아에서의 가와사끼병은 매우 드물고, 그 임상 양상이 비정형적이어서 조기 진단과 치료가 어렵고 심혈관계 합병증의 발생률이 높다. 이에 저자들은 이들의 임상적 특징을 알아봄으로써 이 환아군에서 가와사끼병의 조기 진단과 치료의 중요성을 강조하고자 하였다. 방 법 : 1998년 1월부터 2002년 7월까지 치료했던 전체 가와사끼병 환자 중에서 3개월 이하의 영아 11명을 대상으로 후향적 조사를 하였다. 결 과 : 전체 환자 291명 중 3개월 이하의 영아는 11명(3.8%)이었다. 이들 중 10명이 비정형 가와사끼병 환아로서, 주증상의 발현은 기존의 보고보다 적게 나타났고, 발열을 제외한 주증상 중 가장 흔한 증상은 구강점막의 변화(72.7%)였다. BCG 접종부 위의 발적은 6명의 환아에서 관찰되었는데(나머지 5명은 기록 미비로 알 수 없었음) 그중 2명에서는 아급성기에 심혈관계 합병증이 발생됨으로써 이러한 소견이 명백한 진단의 단서가 될 수 있음이 증명되었다. 면역글로불린(IVIG)의 발병 4.4일 이내의 조기 치료로 10명에서 즉각적인 임상적 호전을 보였으며, 1명에서는 IVIG 재치료를 하였다. 6명(54.5%)에서 심혈관계 합병증이 발생하였으나 추적검사에서 대부분 정상화되었다. 결 론 : 3개월 이하의 영아 가와사끼병 환아는 대부분 비정형적인 양상을 보이고 심혈관계 합병증의 발생률이 높은 고위험군으로 조기 진단과 치료가 중요하다. 이때 BCG 접종부위의 발적은 임상 증상이 거의 없는 나이 어린 영아 환아에서 매우 중요한 진단의 단서가 될 수 있으리라 생각한다.

• Journal of Cardiovascular Imaging
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• 제30권2호
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• pp.99-108
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• 2022

BACKGROUND: Adding pulsation to the Fontan circulation might change the fate of patients palliated by this procedure. Our aim was to compare the pulsatility index (PI) of the pulmonary artery (PA) between the various modifications of Fontan palliation. METHODS: Doppler-derived PI was measured in PA branches of a cohort of 28 patients palliated by 6 modifications of Fontan procedure. A group of normal individuals was included for comparison. RESULTS: Atriopulmonary connection (APC) group had the highest PA branches PI and statistically was close to the PI of the normal individuals (right pulmonary artery [RPA] PI of 1.58 vs. 1.63; p = 0.99 and left pulmonary artery [LPA] PI of 1.54 vs. 1.68; p = 0.46, respectively). The lowest PA branches PI was seen in the group of extracardiac total cavopulmonary connection (RPA PI of 0.62 and LPA PI of 0.65). Other 4 modifications including the extracardiac conduit with oversewn pulmonary valve, extracardiac conduit with preserved adjusted antegrade flow, extracardiac conduit from inferior vena cava onto the rudimentary right ventricle and lateral tunnel had a mean "RPA and LPA" PI of "1.19 and 1.17", "1.16 and 1.11", "1.13 and 1.11", "0.82 and 0.84", respectively. The modified Dunnett's post hoc test has shown a significant statistical decline in PI of all modifications compared to the normal individuals except for the APC group. CONCLUSIONS: Fontan palliated patients in different groups of surgical modification showed a spectrum of Doppler-derived PI with the highest amounts belong to the groups of pulsatile Fontan.

• Journal of Chest Surgery
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• 제45권1호
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• pp.11-18
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• 2012

Background: The aim of this study is to evaluate the clinical and rhythm outcomes of atrial fibrillation (AF) ablation through a port access approach compared with sternotomy in patients with AF associated with mitral valve diseases. Materials and Methods: From February 2006 through December 2009, 135 patients underwent biatrial AF ablation with a mitral operation via either a port-access approach (n=78, minimally invasive cardiac surgery [MICS] group) or a conventional sternotomy (n=57, sternotomy group). To adjust for the differences in the two groups' baseline characteristics, a propensity score analysis was performed. Results: After adjustment, there were no significant differences in the two groups' baseline profiles. The cardiopulmonary bypass time was significantly longer (p=0.045) in the MICS group ($176.0{\pm}49.5$ minutes) than the sternotomy group ($150.0{\pm}51.9$ minutes). There were no significant differences (p=0.31) in the two groups' rate of reoperation for bleeding (MICS=6 vs. sternotomy=2, p=0.47) or the requirement for permanent pacing (MICS=1 vs. sternotomy=3). The major event-free survival rates at two years were $87.4{\pm}8.1%$ in the MICS group and $89.6{\pm}5.8%$ in the sternotomy group (p=0.92). Freedom from late AF at 2 years was $86.8{\pm}6.2%$ in the MICS group and $85.0{\pm}6.9%$ in the sternotomy group (p=0.86). Conclusion: Both the port-access approach and sternotomy showed tolerable clinical outcomes following biatrial AF ablation with mitral valve surgery.

• 한국임상수의학회지
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• 제22권4호
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• pp.396-400
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• 2005

13년령의 암컷 말티즈견이 5개월간의 일시적인 기절현상 (syncope)을 주증상으로 내원하였다. 환축은 병력 청취 신체검사 심장검사 총혈액검사, 혈액 화학적 검사, 방사선학적 검사, 심전도 검사, 아트로핀 반응 검사 (atropine response test), 호르몬 검사, 심전도 검사 등을 통해 심장의 문제가 있는 것으로 진단되었다. 본 증례에서 심전도 검사는 아트로핀 투여에 의한 심전도 기록을 통해 sick sinus syndrome을 확진 하는데 중요한 역할을 하였다. 임상 증상은 테오필린 (THEOLANi, 근화제약, 서울, 한국, 20mg/kg, 경구 투여, 1일 2회)을 복용하면서 개선되었다. 환축은 10개월을 생존하였으나 지역 병원에서 복강의 종괴를 제거하는 수술을 받는 중 호흡곤란과 쇼크로 사망하였다. 사망 후 보호자의 반대로 부검은 이루어지지 않았다.

• Journal of Chest Surgery
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• 제33권8호
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• pp.648-654
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• 2000

Background: Cardiopulmonary bypass during open heart surgery causes systemic inflammatory respose. IL-10 is an anti-inflammatory cytokine that inhibits inflammatory process and protects organ function by down regulation of pro-inflammatory cytokine release and maintenance of blood level balance with pro-inflammatory cytokines. Mateial and Method: Plasma IL-10 levels were measured and analyzed in 22 patients who underwent open heart surgery (11 cases of coronary artery bypass graft, 11 cases of valve replacement) under cardiopulmonary bypass since 1988 January to July at Department of Thoracic and Czardiovascular surgery, Yeungnam University Hospital. 1g of methylprednisolone was administrated to thirteen patients randomly. Blood samp.es were taken and collected at the time of induction of anesthesia, 10 min before cardiopulmonary bypass, 10 min after starting of CPB, 10 min aftr aortic cross clamping, 10 min after ACC release, and 10 min, 2 hours, and `5 hours after CPB respectively. The plasma levels of IL-10 were determined by enzyme-linked immunosorbent assays(ELISA). Wilcoxon-Raule Sum test was used for statistical analysis. Result: In all 22 patients, cardiopulmonary bypass time was used for statistical analysis. Result: In all 22 patients, cardiopulmonary bypass time was 171$\pm$41.4 min and aortic cross clamp time was 118$\pm$36.5 min. Peak IL-10 level was achieved at 10 min after ACC(361.0$\pm$52.81pg/ml) and was decreased sharply at 2 hours after CPB. Peak IL-10 level was correlated positively with aortic cross clamp time(p=0.011); however, it did not correlated with bypass time(p=0.181). In valve replacement group, mean IL-10 level at peak point was 567.89$\pm$107.69 pg/ml and was significantly higher than that of coronary artery bypass group(205.67$\pm$192.70 pg/ml)(p<0.001). ACC time in valve replacement group was significantly longer than that of coronary artery bypass group(p<0.01), however, bypass time was not(p=0.212). Thirteen patients with steroid pretreatment before starting of CPB showed relatively higher plasma IL-10 level than in control group, however, no statistical significance was noted(p=0.19). Conclusion: plasma level of IL-10 was increased in association with cardiopulmonary bypass and revealed peak at 10 min after ACC release. IL-10 level was correlated positively with ACC time. Therefore, systemic inflammatory respeonse in association with cardiopulmonary bypass could be decreased by reducing ACC time during cardiac surgery.