• YAKHAK HOEJI
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• v.41 no.1
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• pp.117-125
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• 1997

The pharmacological effects of benzopyran potassium channel openers (lemakalim, KR-30450 and KR-30818) on the occlusion/reperfusion-induced myocardial infarction were investigat ed. In anesthetized rats, subjected to 45-min occlusion of the left anterior descending coronary artery (LAD) followed by 90-min reperfusion, the infarct size was measured by calculating the ratio of infarct zone to area at risk (IZ/AAR) with the Evans blue/TTC technique. Rats were intravenously given vehicle (1% DMSO), lemakalim, KR-30450, and KR-30818 alone or in combination with a selective K$_{ATP}$ blacker glibenclamide, 30 min prior to coronary occlusion. Compared to vehicle, lemakalim (30 ${\mu}$g/kg i.v.), the active enantiomer of cromakalim, had a tendancy to decrease infarct size. KR-30450(30 ${\mu}$g/kg, i.v.). the newly synthetized potassium channel openers (PCOs), caused a reduction of infarct size (from 70${\pm}$4%to 57${\pm}$5%). but KR-30818 (30 ${\mu}$g/kg, i.v.), a metabolite of KR-30450. did not modify infarct size. It seem ed likely that glibenclamide (0.3mg/kg, i.v.), given in combination, reduced the effects of these PCOs, especially KR-30450 (30 ${\mu}$g/kg, i.v.) on the infarct size. These results indicate that. in the coronary occluded rat model of ischemia, lemakalim and KR-30450 may exert cardioprotective activity through a reduction of infarct size, the effect being considered related to the opening of K$_{ATP}$ channel.

• Journal of Chest Surgery
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• v.42 no.1
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• pp.22-27
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• 2009

Background: Coronary artery bypass grafting (CABG) is the standard surgical treatment for coronary artery disease. Although there are many clinical reviews of the long term results after CABG in the Western countries, not many such studies have been done for Korea. Therefore, we reviewed the long term clinical results for the patients who underwent CABG at our hospital. Material and Method: We retrospectively reviewed the medical records of 342 patients who underwent CABG at our hospital from February 1984 to December 2006, which is when CABG was first performed in our institution. A total of 286 patients (83.6%) were able to be followed-up, and the mean follow-up period was $75.7{\pm}46.1$ months. Result: The early mortality rate was 5.6%, and late mortality rate was 23.1%. The one-year survival rate, the five-year survival rate, the ten-year survival rate and the fifteen-year survival rate were 91.5%, 82.1%, 60.7% and 50.0%, respectively. The survival rate was significantly lower for the patients over the age of 60 (p=0.002) and for those with diabetes mellitus (p=0.000), hypertension (p=0.002), multivessel disease (p=0.006) and left ventricular dysfunction (p=0.015). No significant difference was observed between the genders. Multivariate analysis showed that the statistically significant risk factors were diabetes mellitus (p=0.001), age (p=0.005) and those cases for which the left internal thoracic artery was not used (p=0.037). Conclusion: CABG is the effective method of treatment for coronary artery disease. Therefore, active usage of the internal thoracic artery and appropriate medical treatment after surgery, and especially for diabetes mellitus patients, are mandatory for achieving good long-term survival.

• 대한핵의학회:학술대회논문집
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• 2000.05a
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• pp.75.1-75.1
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• 2000

• Journal of Chest Surgery
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• v.52 no.3
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• pp.189-189
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• 2019

• Journal of Chest Surgery
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• v.40 no.3 s.272
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• pp.168-179
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• 2007

Background: The recent trend of an increasing number of patients with acute cardiogenic shock or chronic congestive heart failure following myocardial infarction, as well as the considerable number who can not be weaned from cardiopulmonary bypass after open heart surgery, call for immediate efforts to develop affordable ventricular assist devices that are suitable for the Korean physique. Recently, a pneumatic pulsatile ventricular assist device (VAD), named DKUH-75, has been developed by the Department of Biomedical Engineering, in collaboration with the Department of Thoracic and Cardiovascular Surgery of Dankook University College of Medicine. The feasibility of the DKUH-75 VAD was evaluated on the bases of common hemodynamic variables and echocardiographic measurements in pigs, which are subjected to an acute cardiogenic shock state following myocardial infarction, using a novel coronary artery ligation method employing the ischemic preconditioning concept. Material and Method: Acute cardiogenic shock was induced in 10 Yorkshire Landrace Duroc strain pigs by ligating the left anterior descending coronary artery via an ischemic preconditioning process. The hemodynamic variables were monitored, with epicardial echocardiographic measurements performed before and one hour after the ligation. The DKUH-75 VAD was implanted into 5 pigs one hour after the onset of the shock. The hemodynamic variables and echocardiographic measurements were taken one hour after installation of the VAD. Result: The systolic, diastolic and mean systemic arterial pressures were significantly decreased in all the experimental animals one hour after the ligation. The systolic, diastolic and mean pulmonary arterial pressures were increased (Eds note: this completely contradicts the preceding statement? However, if you mean the non-experimental animals this should be stated?). The left ventricular end diastolic pressure (LVEDP) was increased, but the cardiac index decreased, An increase in the left ventricular end systolic dimension and decreases in the fractional shortening and ejection fraction were observed all animals one hour after the coronary artery ligation. In all 5 of the VAD implanted pigs, the systolic and mean systemic arterial pressures were increased, and the pulmonary arterial pressures decreased one hour after the implantation; the LVEDP decreased, but the cardiac index was significantly increased, In the echocardiographic measurements, the left ventricular end systolic dimension decreased after the implantation of the VAD, but the fractional shortening and ejection fraction significantly increased. Conclusion: Significant improvements in the hemodynamic variables and echocardiographic measurements were observed in the 5 VAD implanted animals one hour after installation, which had been subjected to an acute cardiogenic shock state by ligation of the coronary artery, indicating that the DKUH-75 VAD could help in the recovery of the myocardial function. This suggests that the DKUH-75 VAD is feasible in the short term in relation to an acute cardiogenic shock state due to myocardial infarction.

• Journal of Chest Surgery
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• v.23 no.5
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• pp.987-993
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• 1990

An unusual but often lethal complication of mitral valve replacement is rupture of the left ventricle. From March 1977 through June 1990, 424 mitral valve replacements were performed as isolated or combined procedures. Rupture of the posterior wall of the left ventricle was observed in 3 patients. Their was one type I and two type II rupture. Once the diagnosis was made, all of the patient were connected to the heart-lung machine again and total cardiopulmonary bypass is re-established. Repair was attempted in all of them from the outside of the heart. One of them was successively repaired but two were failed due to myocardial ischemia by circumflex coronary artery injury and failure of adequate closure of the ruptured site. From this results, we concluded that prevention is the best solution. But if we encountered this condition, early diagnosis and rapid treatment may improve the patient`s chances for survival.

• The Korean Journal of Nuclear Medicine
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• v.39 no.2
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• pp.133-140
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• 2005

The potential for recovery of left ventricular dysfunction after myocardial revascularization represents a practical clinical definition for myocardial viability. The evaluation of viable myocardium in patients with severe global left ventricular dysfunction due to coronary artery disease and with regional dysfunction after acute myocardial infarction is an important issue whether left ventricular dysfunction may be reversible or irreversible after therapy. If the dysfunction is due to stunning or hibernation, functional improvement is observed. but stunned myocardium may recover of dysfunction with no revascularization. Hibernation is chronic process due to chronic reduction in the resting myocardial blood flow. There are two types of myocardial hibernation: "functional hibernation" with preserved contractile reserve and "structural hibernation" without contractile reserve in segments with preserved glucose metabolism. This review focus on the application of F-18 FDG and other radionuclides to evaluate myocardial viability. In addition the factors influencing predictive value of FDG imaging for evaluating viability and the different criteria for viability are also reviewed.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.48-53
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• 1995

This study investigates a simple mathematical model for the quantitative estimation of regional myocardial blood flow in experimental canine coronary artery thrombosis using Rb-82 dynamic myocardial positron emission tomography. The coronary thrombosis was induced using the new catheter technique by narrowing the lumen of coronary vessel gradually, which finally led to partial obstruction of coronary artery. Ten Rb-82 dynamic myocardial PET scans were performed sequentially for each experiment using our 5, 10 and 20 second acquisition protocol, respectively, and three regions of interest were drawn on the transaxial slices, one on left ventricular chamber for input function and the other two on normal and decreased perfusion segments for the flow estimation in those regions. Single compartment model has been applied to the measured sets of regional PET data, and the rate constants of influx to myocardial tissue were calculated for regional myocardial flow estimates with the three parameter fits of raw data by the Levenberg-Marquardt method. The results showed that, (1) single compartment model suggested by Kety-Schmidt could be used for the simple estimation of regional myocardial blood flow, (2) the calculated regional myocardial blood flow estimates were dependent on the selection of input function, which reflected partial volume effect and left ventricular wall motion, and (3) mathematically fitted input and tissue time activity curves were more suitable than the direct application of the measured data in terms of convergence.

• Journal of Chest Surgery
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• v.32 no.2
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• pp.181-184
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• 1999

Systolic coronary arterial narrowing, secondary to myocardial bridging which is capable of producing chest pain, myocardial infarction and ventricular fibrillation is a known but an uncommon entity. A supra-arterial myotomy in a case of myocardial bridge causing medication-refractory angina is described. Under the partial sternotomy incision, we performed a supra-arterial myotomy in the left anterior descending coronary artery without cardiopulmonary bypass. The postoperative course was uneventful.

• Journal of Chest Surgery
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• v.19 no.4
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• pp.595-605
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• 1986

From February 1986 through September 1986, the authors have experienced 6 cases of coronary artery bypass graft for patients with unstable angina. There were five males and one female who ranged from 39 to 65 years [mean, 53.3 years]. The extent of coronary disease was as follows: one-, two- and three-vessel diseases, all 2 cases respectively, and among them, 1 case had left main disease. Distal anastomoses were performed first with using saphenous vein grafts as conduits in all cases and sequential bypass methods were employed in 5 cases. Numbers of vein grafts were two in 2 cases and one in 4 cases. The mean time wasted for one distal anastomosis was 36 minutes. Post operative complications were leg-wound disruption [2 cases], transient psychosis [1 case] and perioperative myocardial infarction [MI] [1 case]. Sixty three year-old male patient associated with cardiomegaly, prior MI, ventricular arrhythmia, cardiac dysfunction and endocrinologic diseases preoperatively was expired in the operating room due to perioperative Ml. All survivors were asymptomatic and on discontinuing medical therapy on follow-up varying from 1 to 8 months.