• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.9
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• pp.2013-2018
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• 2011

Coronary angioplasty and coronary artery bypass graft, both are for the treatment of myocardial infarction widely used methods. For these procedures, there are especially difficulties in stenosis of blood vessels to diagnose accurately. To remedy this problem, by several researchers by using edge detection to detect stenosis of blood vessels has been studying. However, the results of using these methods vary defend on the vascular structure and the quality of the image. In this study, to improve these problems, the new algorithm is proposed. The proposed algorithm consists of methods to detect bifurcation of blood vessels and its ending point by using multi sampling, threshold and fuzzy algorithm. To evaluate the performance of the proposed algorithm, angiography was used for the different results of the blood vessels of the proposed algorithm, and the result was effective in detecting bifurcation of blood vessels and its ending point.

• Journal of Chest Surgery
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• v.39 no.8 s.265
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• pp.604-610
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• 2006

Background: Recent improvements in interventional procedure and medical therapy for congestive heart failure result in an increase of number of patients with ischemic cardiomyopathy considered for coronary artery bypass grafting. We retrospectively review the results of CABG in these patients with decreased LV function to know the early and mid-term follow-up results. Material and Method: Between January 2001 and June 2005, 1,143 patients underwent coronary artery bypass grafting and 144 of these patients had preoperative left ventricular function of equal to or less than 35% ${(LVEF{\leq}\;35%)}$. There were off-pump coronary artery bypass grafting (OPCAB) in 66 cases (45.8%), on-pump beating heart coronary artery bypass grafting in 34 cases (23.6%) and conventional coronary artery bypass grafting in 44 cases (30.6%). The combined operations including mitral annuloplasty were 48 cases in thirty five patients (24.3%). Result: The mean number of dstal anastomosis were $3.5{\pm}1.3$. The median postoperative duration of stay in intensive care unit and hospital was 2 days and 8 days, respectively. There were 6 early death (4.2%) and causes of deaths were ventricular tachycardia in 5 patients, small bowel infarction in one patient. Mean follow-up time was $21{\pm}14$ months $(4{\sim}54\;months)$. The 1-year was $95{\pm}2%$ and 3-year survival rate was $83{\pm}7%$, the 1-year and 3-year cardiac event-free survival were ${88{\pm}3%\;and\;69{\pm}7%}$, respectively. Conclusion: Based on satisfactory early and mid-term results in our study, CABG should be carried out as actively as possible in patients with ischemic cardiomyopathy. Postoperative aggressive management for ventricular arrhythmia would be helpful for better results.

• Journal of Chest Surgery
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• v.30 no.10
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• pp.966-972
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• 1997

Between June 1994 to August 1996, 13 patients underwent emergency coronary artery bypass operations. There were 3 males and 10 females and ages ranged from 56 to 80 years with the mean of 65.5 years. The indications for emergency operations were cardiogenic shock in 12 cases and intractable polymorphic VT(ve'ntricular tachycardia) in 1 case. The causes of cardiogenic shock were acute evolving infarction in 6 cases, PTCA failure in 4 cases, acute myocardial infarction in 1 case, and post-AMI VSR(ventricular septal rupture) in 1 case. Pive out of 13 patients could go to operating room within 2 hours. However, the operations were delayed from 3 to 10 hours in 8 patients due to non-medical causes. In 12 patients, 37 distal anastomoses were constructed with only 3 LITA's(left internal thoracic arteries) and 34 saphenous veins. In a patient with post-AMI VSR, VSR repair was added. In a patient with intractable VT and critical sten sis limited to left main coronary artery, left main coronary angioplasty was performed. Pive patients died after operation with the operative mortality of 38.5%. Three patients died in the operating room due to LV pump failure, one patient died due to intractable ventricular tachycardia on postoperative second day, and one patient died on postoperative 7th day due to multi-organ failure with complications of mediastinal bleeding, low cardiac output syndrome, ARF, and lower extremity ischemia due to IABP. In 8 survived patients, 3 major complications (mediastinitis, PMI, UGI bleeding) developed but eventually recovered. We think that the aggressive approach to critically ill patients will salvage some of such patients and the most important factor for patient salvage is early surgical intervention before irreversible damage occurs.

• The Korean Journal of Nuclear Medicine
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• v.34 no.1
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• pp.39-54
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• 2000

Purpose: Dipyridamole stress myocardial perfusion SPECT could predict prognosis, however, long-term follow-up showed change of hazard ratio in patients with suspected coronary artery disease. We investigated how long normal SPECT could predict the benign prognosis on the long-term follow-up. Materials and Methods: We followed up 1169 patients and divided these patients into groups in whom coronary angiography were performed and were not. Total cardiac event rate and hard event rate were predicted using clinical, angiographic and SPECT findings. Predictive values of normal and abnormal SPECT were examined using survival analysis with Mantel-Haenszel method, multivariate Cox proportional hazard model analysis and newly developed statistical method to test time-invariance of hazard rate and changing point of this rate. Results: Reversible perfusion decrease on myocardial perfusion SPECT predicted higher total cardiac event rate independently and further to angiographic findings. However, myocardial SPECT showed independent but not incremental prognostic values for hard event rate. Hazard ratio of normal perfusion SPECT was changed significantly (p<0.001) and the changing point of hazard rate was 4.4 years of follows up. However, the ratio of abnormal SPECT was not. Conclusion: Dipyridamole stress myocardial perfusion SPECT provided independent prognostic information in patients with known and suspected coronary artery disease. Normal perfusion SPECT predicted least event rate for 4.4 years.

• Journal of Chest Surgery
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• v.29 no.6
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• pp.639-645
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• 1996

A 14-year-old male patient with previous surgical repair of tetralogy of Fallot was admitted with hemodynamically significant ventricular tachycardia (VT). On preoperative electrophysiologic study (EPS), the morphology of documented VT was RBBB of vertical axis with 320 msec cycle length. The endocardial mapping during VT delineated the origin of VT at right ventricular outflow tract (RVOT), where the patch was attached. The clinical VT had a clockwise reentry circuit around the patch with the earliest activation at the same site seen during the preoperative EPS. The previously placed right ventricular outflow patch and fibrous tissue were removed. During a postoperative EPS, it was no longer possible to induce the VT. Ventricular tachycardia following repair of tetralogy of Fallot seen in this patient was caused by a macro-reentry around the right ventricular outflow patch. We were able to ablate the VT with the aid of a detailed mapping of its epicardial activation sequence.

• Journal of Chest Surgery
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• v.30 no.2
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• pp.158-163
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• 1997

From July 1994 to August 1995, 32 patients underwent coronary artery bypass surgery. There were 14 men and 18 women. The mean age was 59 years (range from 37 to 81 years). Preoperatively 26 patients had unstable angina pectoris and 6 patients had stable angina pectoris. Nine patients had previous myocardial infarction hi tory. Five patients had preoperative left ventricular ejection fraction of 40% or less, The involved risk factors were as follows ; smoking 19 cases, hypertension 16 cases, hypercholesterolemia 14 cases, diabetes mellitus 6 cases, and obesity 3 cases.21 patients had three-vessel disease, 7 patients had two-vessel disease, 2 patients had one-vessel disease and 2 patients had left main coronary artery disease. We performed 103 distal bypasses out of 32 cases, and the mean number of grafts per patients is 3.22. We used arterial grafts (left internal mammary artery,)1, radial artery; 2) in 32% of total grafts. Postoperative complications were low cardiac output, perioperative myocardial infarction, respiratory failure and atrial fibrillation, etc. Early mortality was 6.25% (2/32). The causes of deaths were low cardiac output (1), and perioperative myocardial infarction(1).

• Journal of Yeungnam Medical Science
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• v.17 no.1
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• pp.31-38
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• 2000

Background: We sought to examine the use and outcomes of early intraaortic balloon counterpulsation(IABP) combined with early reperfusion therapy in patients presenting cardiogenic shock complicated acute myocardial infarction. The usc of IABP in patients with cardiogenic shock is widely accepted. However there is not ample information on the use of this technique in patients with cardiogenic shock who arc treated with reperfusion therapy in Korea. Materials and Methods: Twenty-eight patients presented with cardiogenic shock were classified into two groups: the early IABP group (insertion within 12 hours after AMI onset time) and the late IABP group (insertion after 12 hours). We compared In-hospital mortality between the two groups (early IABP group vs late IABP group). Results: Two groups showed no significant difference in clinical feature and coronary angiographic results. Among total 28 patients, 7 patients were treated with thrombolytic therapy and 21 patients with PTCA. Insertion site bleeding, fever, thrombocytopenia were reported as some of the complications of IABP insertion. In-hospital mortalities in the early IABP group and late IABP group were 4 patients(25%) and 8 patients(66%), respectively(p<0.05). Early IABP insertion and early PTCA showed lower hospital mortality rates. There was significant difference in the time to PTCA after AMI onset between the two groups(p<0.05). Conclusion: IABP appears to be useful in patients presenting cardiogenic shock unresponsive medical therapy. Early IABP insertion and early reperfusion therapy may reduce in-hospital mortality rates of post-MI cardiogenic shock patients.

• Journal of Chest Surgery
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• v.34 no.12
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• pp.901-908
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• 2001

Background : Coronary artery bypass graft(CABG) in patients with advanced left ventricular dysfunction has often been regarded as having high mortality rate, despite the great improvement in operative result of CABG. With recent advances in surgical technique and myocardial protection, surgical revascularization improved the symptom and long-term survival of these high risk patients more than the medical conservative treatment. Material and Methold : Clinical data of 31(4.1％) patients with preoperative ejection fraction less than 30% among 864 CABGs performed between January 1995 and March 1999 were retrospectively analyzed and pre- and postoperative changes of the ejection fraction on echocardiography were analyzed. There were 26 men and 5 women. The mean age was 60.7 years(range 41 to 72 years). History of myocardial infarction(30 cases, 98％) was the most common preoperative risk factor. There were seven irreversible myocardial infarction on thallium scan. Most patients had triple vessel diseases(26 cases, 84％) and first degree of Rentrop classification(16 cases, 52％) on coronary angiography. The mean number of distal anastomosis during CABG was per patient was 4.9${\pm}$0.8 sites in each patient. In addition to long saphenous veins, the internal mammary artery was used in 20 patients. Total bypass time was 244.7${\pm}$3.7 minutes(range, 117 to 567 minutes), and mean aortic cross-clamp time was 77.9 ${\pm}$ 1.6 minutes(range, 30 to 178 minutes). There were five other reparative procedures such as two left ventricular aneurysrmectomy, two mitral repair, and one aortic valve replacement. There were twelve postoperative complications such as three cardiac arrhythmia, two bleeding(re-operation), one delayed sternal closure, eleven usage of intra-aortic balloon counterpulsation for low cardiac output. Two patients died, postoperative mortality was 6.5% . Twenty-nine patients were relieved of chest pain and left ventricular ejection fraction after operation was significantly higher(38.5${\pm}$11.6%, p 0.001) as compared with preoperative left ventricular ejection fraction(25.3${\pm}$2.3%). The follow up period of out patient was 25. 3 months. Conclusion: In patients with coronary artery disease and advanced left ventricular dysfunction, coronary artery bypass grafting can be performed relatively safely with improvement in left ventricular function, but it will be necessary to study long term results.

• Journal of Yeungnam Medical Science
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• v.20 no.2
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• pp.197-205
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• 2003

서론: 급성 관동맥 증후군과 심근경색증의 진단과 예후 예측에 도움을 주는 새로운 심효소인자가 여러 가지 발견이 되어 현재 응급의료센터에서도 기본적으로 허혈성 흉통이 있는 환자에게 많이 사용하고 있다. 특히 최근에는 troponin과 CK-MB의 유용성에 대해서 많이 언급을 하고 있다. CRP도 역시 급성 관상동맥증후군에서 중요성이 인식되고 있다. 저자들은 세 가지 인자를 동시에 평가하여 상승되는 인자 수에 따라 그 중요성이 다를 수 있다는 가정 하에 총체적인 환자에 대한 정보를 제공할 수 있고, 응급실 근무 의사에게 급성 심근 경색증 환자를 좀 더 효율적으로 평가 할 수 있도록 하기 위하여 다표지 인자에 관한 연구를 시작하였다. 방법: 저자들은 응급의료센터에 내원한 급성 허혈성 흉통이 있는 환자 중 심효소 검사와 심전도에서 급성 심근 경색증에 합당한 소견을 보이고 이후 검사한 심혈관 조영술에서 심근경색증으로 확진된 환자를 대상으로 하였다. 내원 초기에 troponin T와 CK-MB, CRP를 동시에 측정하였고 또한 후향적으로 환자에 대한 기본적인 특징과 정보, 심전도 소견, 합병증 발생, 심혈관 조영술 소견과 경색관련 혈관 수, 치료 및 치료결과 등에 대한 자료를 정리하여 분석하여 보았다. 이때 환자는 두 군으로 나누어 분석하였는데, 1군은 증가된 효소수가 1개 이하인 경우이고, 2군은 2개 또는 3개 및 좌주관상동맥을 포함한 경우로 하였다. 결과: 전체 130명의 환자가 대상이 되었고, 1군 40례, 2군 90례로 2군이 훨씬 많았다. 과거력에서 이전에 관동맥 성형술을 시술받은 경우가 2군에서 유의 있게 많았다(p<0.05). 이전의 약물 복용은 전체적으로 1군에서 많았으나 질산제 복용(p<0.05)을 제외하고는 의의가 없었다. 치료는 혈전용해제 사용이 오히려 1군에서 의의있게 많았으나(p<0.05), 합병증으로 쇽이나 폐부종을 동반한 경우가 2군에서 많았다. 하지만 본 연구에서는 6개월 추적 기간중의 사건 발생이나 합병증, 예후 결과에 대한 양군간의 차이를 발견하지 못했다. 결론: 급성 심근경색증 환자에게 다표지 인자를 이용한 접근법을 적용한 결과, 기본적으로 환자에 대한 몇 가지 정보, 즉 과거에 약물 투여 여부와 혈전용해제 사용, 혈관성형술을 시술 받은 경력과 같은 기초자료에 대한 제한적인 차이를 발견할 수 있었으나, 본 연구에서는 다표지 인자를 이용하여 추적기간중 환자의 상태와 예후를 평가하고 합병증을 조기에 예측한다든지 하는 중요한 역할을 발견하지 못하였다. 그래서 향후 이에 대한 제한점을 해결한 더 보완된 연구가 필요할 것으로 사료된다.

• Journal of Chest Surgery
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• v.30 no.3
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• pp.287-292
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• 1997

.Itrial fibrillation is one of the most common cardiac arrhythmias requiring treatment. About 60% of patients with mitral valvular disease have atrial fibrillation and one third of patients with atrial fibrillation may have the past history of thromboembolic events. Between April 1994 and June 1995, 20 patients with organic heart diseases combined with atrial fibrillation underwent open heart surgery including Cox-maze 111 procedure. There were 6 men and 14 women with an average age of 48 years (range, 31 to 66 years). Nineteen patients had valvular heart diseases and 1 ventricular septal defEct (VSD). Mean duration of atrial fibrillation was 36 months (:42 months) (range, 1 to 132 months). T e past medical history of thromboembolic events was positive in 7 patients (35%) and left atrial thrombus was detected in 9 patients (45%). The concomitant procedures were mitral valve replacement (MVR) and aortic valve replacement (AVR) in 5 patients, MVR in 4, MVd and tricuspid annuloplasty(TAP) in 4, mitral valvuloplasty(Mln) in 3, Mln and Tln in 1, MIW and coronary artery bypass surgery in 1, AVR in 1, and patch closure of VSD in 1. Mean aortic cross-clamping time was 175 minutes (range, 116 to 270 minutes). Atrial fibrillation recurred in 16 patients (80%) during the early postoperative period, but, recurrent atrial fibrillation was converted to regular rhythm at postoperative forty-first day in average. There was no early or late death in this series of 20 patients and postoperative complications were inappropriate tachycardia in 5 patients (25%), low cardiac output syndrome in 3 (15%), aggravated hemiplegic in 1, and acute renal failure in 1. Mean follow-up interval of patient was 16.5 months (range, 10.5 to 24 months) and all patients are currently in regular rhythm. Seventeen patients (85%) are in sinus rhythm and 3 (15%) in junctional rhythm. Right atrial contraction was detected in 95% of patients and left atrial contraction in 63% on postoperative transthoracic echocardiogram. The surgical treatment of atrial fibrillation concomitant with open heart surgery is warranted in the recent clinical setting of improved myocardial protection technique, considering the untoward side-effects of atrial fibrillation.