OBJECTIVES: To investigate the role of ATP-sensitive potassium channel (KATP) during sustained ventricular fibrillation (VF), the effects of gliburide, a specific blocker of KATP channel and PCO400, an KATP opener, were studied in isolated and perfused swine right ventricular free walls (n=). METHODS: Recording of single cell transmembrane potentials was performed and constructed action potential duration restitution (APDR) curve by plotting APD 90%(APD90) versus preceding diastolic interval (DI). RESULTS: All isolated tissues fibrillated spontaneously. In this preparation, stable VF could persist over a 4-hour period if it was allowed to continue undisturbed (n=). Gliburide (1-5 uM) increased DI without significant changes in APD90 during VF, resulting in more regularization of VF. Higher concentration (10-20 uM) increased both APD90 and DI, and converted to monomorphic ventricular tachycardia (MVT) through the transitional period characterized by APD alternans. PCO400 (1-2.5 uM) caused a significant shortening of APD during MVT and a period of APD alternans became more evident before conversion from MVT to VF. Gliburide eliminated profibrillatory effect of PCO400. This antifibrillatory action of gliburide was accompanied by gradual decrease in the maximum slope of APDR curve during VF. CONCLUSION: KATP channel blockade causes a transition from VF to MVT via lengthening of DI and APD alternans, concomitantly with a reduction of the slope of APD restitution curve.
Action Potentials ; Membrane Potentials ; Potassium Channels ; Swine ; Tachycardia, Ventricular ; Ventricular Fibrillation*

Purpose: To evaluate the long-term clinical outcomes of vitrectomy with internal limiting membrane (ILM) removal for patients with macular hole retinal detachment (MHRD). Methods: We retrospectively reviewed the medical records of patients with MHRD who underwent vitrectomy with ILM removal. The incidence of retinal re-attachment and MH closure at 1 month were calculated. Factors associated with RD recurrence were investigated. Visual acuity before surgery was compared to that at the final visit. Results: Forty-two eyes were included; the mean follow-up period was 38.5 ± 19.1 months. Twenty-three eyes received gas injections and 19 silicone oil injections. Retinal re-attachment occurred in 41 (97.6%). Type 1 closure was noted in 21 eyes (51.2%) and type 2 in 20 (48.8%). Recurrent RD was noted in five eyes (14.6%) within 3 months of initial surgery. Type 2 closure was a risk factor for recurrence (p = 0.021). The logarithm of the minimum angle of resolution best-corrected visual acuity improved significantly from 1.79 ± 0.79 before surgery to 1.30 ± 0.75 after surgery (p < 0.001). Conclusions Retinal re-attachment was noted in most patients and the MH closed in approximately half of all patients after vitrectomy with ILM removal to treat MHRD. RD did not recur later than 3 months after initial surgery. Further efforts to increase the rate of type 1 closure are required.

BACKGROUND: QT dispersion(QTD : QTmax-QTmin) or JT dispersion(JTD:JTmax-JT-min)in 12 leads ECG has been known to reflect regional variations in ventricular repolarization and has been reported to bel one of the marker of regional myocardial ischemia. To evaluate the significance of QTD or JTD of exercise ECG in diagnosis of coronary artery disease, we studied 106 patients(mean age, 56.9 years old, male 63) who were referred for the evaluation of chest pain on exertion. METHOD: Treadmill exercise stress test with modified Bruce protocol and coronary angiography were performed in 106 patients with chest pain on exertion. ST-segment depression by >1.0 mm 0.08 second after J-point during or after exercise in exercise test and >50% stanosis of epicardial artery in coronary angiogram were defined as positive. Of 106 patients, 41 had positive exercise ECG and positive coronary angiogram(true positive, TP), 20 had positive exercise ECG and negative coronary angiogram(false positive, FT), 20 had negative exercise ECG and positive coronary angiogram(faalse negative, FN), and 23 had negative exercise ECG and negative coronary angiogram(true negative, Tn). QT and JT interval in 12 leads were measured at baseline and peakexercise and were corrected for heart rate using Bazett's formula. QTD and JTD were measured by calculation the difference between the maximum QT and mininum QT and that between maximum JT and minumum JT. RESULTS: QTD at baseline for TP(72.8ms)was prolonged compared to Tn(52.2ms,P<0.01), but was not different from that for FT(70.2 ms). At peak exercise, QTD for TP(81.3 msec) was significantly prolonged(p<0.01), while QTD for FP(71.2 msec) was not different from that for TN(56.8 msec). JTD at baseline(78.4 msec) and at peak exercise(88.2 msec) for TP were significantly prolonged compared to those for TN(55.2msec and 55.1msec p<0.01,p<0.01, respectively), but those for FP were not porlonged(77.0msec and 79.0msec, respectively). QTD and JTD at peak exercise were more markedly prolonged in patients with sever stenosis of coronary artery(p=0.053 and p<0.05, repectively) and multivessels diseases(p<0.01, 0<0.05) than those with less severe disease and single vessel disease. Patients with left anterior descending artery lesion had greater QTD and JTD at peak exercise than those with other vessels lesion(p<0.01). In addition to standard criteria with ST segment displacement in exercise EGC, inclusion of exercise induced QTD of more than 60msec increased the sensitivity of exercise ECG from 66.7% to 83.3%, and JTD of more than 70msec increased the specificity from 52% to 76.0%. CONCLUSION: Measurement of QT dispersion and JT dispersion of exercise ECG may be useful method to identify the severity of coronary artery disease and to improve diagnostic accuracy of exercise ECG in coronary artery disease.
Arteries ; Chest Pain ; Constriction, Pathologic ; Coronary Angiography ; Coronary Artery Disease ; Depression ; Diagnosis ; Electrocardiography* ; Exercise Test ; Heart Rate ; Humans ; Male ; Myocardial Ischemia ; Sensitivity and Specificity

No abstract available.
Lipomatosis* ; Neoplasm Metastasis* ; Small Cell Lung Carcinoma*

BACKGROUND: It is known that there is a pronounced circardian periodicity for the time of onset of acute myocardial infarction(AMI), with prominent increase in incidence of onset in the morning hours. However, the characteristic circardian variability in AMI is blunted in patients receiving beta-blockers or aspirin therapy before their presentation with AMI. These findings are attributed to the increase in platelet aggregability, blood coagulability, and plasma catecholamine that change coronary tone and myocardial oxygen demand. We hypothesize that, in addition to above physiologic and biochemical parameters, morphologic patterns of the coronary artery lesions are related to the development of circardian variation in AMI. METHOD: Subjects were 160 patients with AMI(male 92, female 68, mean age 56.9 +/-10.5 years old). Patients were classified by the time of onset of typical chest pain(AMI) by 6-hour interval from mid-night. Circardian variability of onset of AMI was compared with clinical findings and coronary angiographic findings. RESULTS: Incidence of onset of AMI was most frequent in the morning hours(6AM-noon,42.5%). There was no difference in degree of stenosis, lesion length, incidence of intraluminal thrombus, among 3 subgroups of AMI according to time of attack. Morning hour group had more frequent ulceration of coronary lesion than that of other groups(22.4% vs. 5.4%, p<0.01), and less frequent calcified lesion than that of other groups(3.0% vs 5.4%, p<0.05). Normal or minimal coronary artery lesion, that is Iess than 25% stenosis, was more frequent in the morning hour group comparing to that of other groups(11.9% vs. 9.78%). Eccentric stenosis(15.7% vs, 11,1%) and diffuse irregular lesion(25.5% vs. 16.7%) tended to be more frequent in the morning hour group. There were no differences in sex, age, incidence of hypertension, cigarette smoking, diabetes, degree of alcohol ingestion, ejection fraction, maximal CK value, preinfarction angina duration, past history of MI, and in incidence of arrhythmia. CONCLUSIONS: There were more ulcerative coronary atherosclerotic lesions, but fewer calcified coronary lesions in the morning group than in afternoon and night group. These findings indicate that morphology of coronary artery lesions may play a role in causing circardian variation in AMI.
Angina, Unstable ; Arrhythmias, Cardiac ; Aspirin ; Blood Platelets ; Constriction, Pathologic ; Coronary Vessels* ; Eating ; Female ; Humans ; Hypertension ; Incidence ; Myocardial Infarction* ; Oxygen ; Periodicity ; Plasma ; Smoking ; Thorax ; Thrombosis ; Ulcer

BACKGROUND: It is known that there is a pronounced circardian periodicity for the time of onset of acute myocardial infarction(AMI), with prominent increase in incidence of onset in the morning hours. However, the characteristic circardian variability in AMI is blunted in patients receiving beta-blockers or aspirin therapy before their presentation with AMI. These findings are attributed to the increase in platelet aggregability, blood coagulability, and plasma catecholamine that change coronary tone and myocardial oxygen demand. We hypothesize that, in addition to above physiologic and biochemical parameters, morphologic patterns of the coronary artery lesions are related to the development of circardian variation in AMI. METHOD: Subjects were 160 patients with AMI(male 92, female 68, mean age 56.9 +/-10.5 years old). Patients were classified by the time of onset of typical chest pain(AMI) by 6-hour interval from mid-night. Circardian variability of onset of AMI was compared with clinical findings and coronary angiographic findings. RESULTS: Incidence of onset of AMI was most frequent in the morning hours(6AM-noon,42.5%). There was no difference in degree of stenosis, lesion length, incidence of intraluminal thrombus, among 3 subgroups of AMI according to time of attack. Morning hour group had more frequent ulceration of coronary lesion than that of other groups(22.4% vs. 5.4%, p<0.01), and less frequent calcified lesion than that of other groups(3.0% vs 5.4%, p<0.05). Normal or minimal coronary artery lesion, that is Iess than 25% stenosis, was more frequent in the morning hour group comparing to that of other groups(11.9% vs. 9.78%). Eccentric stenosis(15.7% vs, 11,1%) and diffuse irregular lesion(25.5% vs. 16.7%) tended to be more frequent in the morning hour group. There were no differences in sex, age, incidence of hypertension, cigarette smoking, diabetes, degree of alcohol ingestion, ejection fraction, maximal CK value, preinfarction angina duration, past history of MI, and in incidence of arrhythmia. CONCLUSIONS: There were more ulcerative coronary atherosclerotic lesions, but fewer calcified coronary lesions in the morning group than in afternoon and night group. These findings indicate that morphology of coronary artery lesions may play a role in causing circardian variation in AMI.
Angina, Unstable ; Arrhythmias, Cardiac ; Aspirin ; Blood Platelets ; Constriction, Pathologic ; Coronary Vessels* ; Eating ; Female ; Humans ; Hypertension ; Incidence ; Myocardial Infarction* ; Oxygen ; Periodicity ; Plasma ; Smoking ; Thorax ; Thrombosis ; Ulcer

BACKGROUND: A number of studies in western countries have shown that coronary artery disease(CAD) and younger patients with acute myocardial infarction(AMI) is less extensive but more. closely related to cigarette smoking. However, there are some similarities between the characteristics of the CAD and the risk factors analyzed by age subsets in patients with AMI in Korea. METHODS: Pre-discharge coronary angiograms and risk factors in 194 patients with first AMI(male/female : 154/40,79.4%/20.6%) were analyzed. A comparison was made between the lesion characteristics of the infarct related artery(IRA) and the CAD risk factors. Those under 49 years old (Group I, n=54, male/female : 50/4 : 92.6%/7.4%) and those over 50 years old ( Group II, n=140, male/female : 104/36 : 74.3%/25.7%). RESULTS: There are 54 and 140 patients in groups I and II respectively. 92% of group I and 74.1% of group II were male (p<0.01). At the time of study, more group I patients were smoking cigarettes and drinking alcohol(over 3 times per week 22.6% vs 11.5%, p<0.01) and insignificant stenosis was more common in group I than in group II. In both groups, the most common IRA was the left anterior descending artery and concurrently the anterior wall was the most common morphological type of coronary stenosis of IRA was concentric irregular in group I(27.7%) and eccentric smooth in groupII(31.5%). Although group I had the larger minimal cross sectional area of coronary stenosis(0.97+/-1.16mm2 and 0.54+/-0.80mm2, respectively, p<0.05, reference diameters 2.71+/-0.60mm and 2.66+/-0.67mm, respectively),the coronary lesion was shorter in group I patients(3.39+/-4.06cm and 5.49+/-6.13cm respecitively, p=0.03). CONCLUSION: These findings reveal that coronary atherosclerotic lesions of IRA in patients with AMI in the younger age group are less severe. However, they are more closely related to cigarette smoking and alcohol intake, than cases in the older age group.
Arteries ; Constriction, Pathologic ; Coronary Stenosis ; Coronary Vessels ; Drinking ; Humans ; Korea ; Male ; Middle Aged ; Myocardial Infarction* ; Risk Factors* ; Smoke ; Smoking ; Tobacco Products

BACKGROUND: A number of studies in western countries have shown that coronary artery disease(CAD) and younger patients with acute myocardial infarction(AMI) is less extensive but more. closely related to cigarette smoking. However, there are some similarities between the characteristics of the CAD and the risk factors analyzed by age subsets in patients with AMI in Korea. METHODS: Pre-discharge coronary angiograms and risk factors in 194 patients with first AMI(male/female : 154/40,79.4%/20.6%) were analyzed. A comparison was made between the lesion characteristics of the infarct related artery(IRA) and the CAD risk factors. Those under 49 years old (Group I, n=54, male/female : 50/4 : 92.6%/7.4%) and those over 50 years old ( Group II, n=140, male/female : 104/36 : 74.3%/25.7%). RESULTS: There are 54 and 140 patients in groups I and II respectively. 92% of group I and 74.1% of group II were male (p<0.01). At the time of study, more group I patients were smoking cigarettes and drinking alcohol(over 3 times per week 22.6% vs 11.5%, p<0.01) and insignificant stenosis was more common in group I than in group II. In both groups, the most common IRA was the left anterior descending artery and concurrently the anterior wall was the most common morphological type of coronary stenosis of IRA was concentric irregular in group I(27.7%) and eccentric smooth in groupII(31.5%). Although group I had the larger minimal cross sectional area of coronary stenosis(0.97+/-1.16mm2 and 0.54+/-0.80mm2, respectively, p<0.05, reference diameters 2.71+/-0.60mm and 2.66+/-0.67mm, respectively),the coronary lesion was shorter in group I patients(3.39+/-4.06cm and 5.49+/-6.13cm respecitively, p=0.03). CONCLUSION: These findings reveal that coronary atherosclerotic lesions of IRA in patients with AMI in the younger age group are less severe. However, they are more closely related to cigarette smoking and alcohol intake, than cases in the older age group.
Arteries ; Constriction, Pathologic ; Coronary Stenosis ; Coronary Vessels ; Drinking ; Humans ; Korea ; Male ; Middle Aged ; Myocardial Infarction* ; Risk Factors* ; Smoke ; Smoking ; Tobacco Products

PURPOSE: Adherence to immunosuppressants is the key to prevent organ rejection in organ transplant recipients. The purpose of this study was to investigate current interventions to improve adherence to immunosuppressants in liver transplant recipients. METHODS: A systemic literature search was done using PubMed, Embase, Cochrane Library, CINAHL and four Korean databases to identify experimental studies reported in English or Korean up to and including 2015. We identified eight intervention studies on the adherence to immunosuppressants in liver transplant recipients independently reviewed by two reviewers. The quality and risk of bias of the selected studies were assessed. RESULTS: Education, conversion of regimen, and text messaging were identified as intervention techniques to improve adherence. We found positive results in three out of four studies implementing educational strategies, but the results were not sufficient to draw a definite conclusion. Conversion from a twice-daily tacrolimus-based regimen to a once-daily tacrolimus extended-release formula was used in three adult-only studies and its effectiveness was confirmed. One study showed that improved adherence and outcomes were effected by using text messaging with pediatric patients. CONCLUSION: Future research is needed to facilitate interventions to improve adherence to immunosuppressants in various ages of patients including pediatric/adolescent liver transplant recipients.
Bias (Epidemiology) ; Education ; Humans ; Immunosuppressive Agents* ; Clinical Trial ; Liver* ; Tacrolimus ; Text Messaging ; Transplantation* ; Transplants

PURPOSE: To evaluate the clinical presentations of focal choroidal excavation and to report long-term outcomes of cases without retinal disorders at the initial presentation. METHODS: A retrospective review of medical records was performed for patients diagnosed with focal choroidal excavation. Concomitant retinal disorders at the initial presentation were identified. In cases without retinal disorders, the development of retinal disorders during follow-up was also evaluated. RESULTS: Forty-five eyes in 45 patients were examined in this study. Focal choroidal excavation was accompanied with retinal disorders in 16 eyes (35.6%). In the remaining 29 eyes, only focal choroidal excavation was noted without any accompanying retinal disorders. The accompanying retinal disorders included choroidal neovascularization (n = 8), central serous chorioretinopathy (n = 4), epiretinal membrane (n = 1), macular hole (n = 1), branch retinal vein occlusion (n = 1), and uveitis (n = 1). Of the 29 eyes without retinal disorders, 22 were followed up for a mean period of 33.5 ± 18.2 months. Consequently, choroidal neovascularization was found to have developed in one eye at 59 months, and subretinal fluid had developed in two eyes at 17 and 28 months, respectively. CONCLUSIONS: Focal choroidal excavation was accompanied by retinal disorders in 35.6% of the included patients. In patients without retinal disorders, the development of a retinal disorder was noted in some eyes, suggesting the need for long-term regular follow-up in patients diagnosed with focal choroidal excavation.
Central Serous Chorioretinopathy ; Choroid ; Choroidal Neovascularization ; Epiretinal Membrane ; Follow-Up Studies ; Humans ; Medical Records ; Retinal Perforations ; Retinal Vein Occlusion ; Retinaldehyde ; Retrospective Studies ; Subretinal Fluid ; Uveitis