Purpose: To analyze changes in refractive error among elementary school children under the age of 13 who visited an outpatient clinic for eye examinations before and after the onset of the COVID-19 pandemic. Methods: A retrospective analysis of medical records was conducted to calculate the spherical equivalent refractive error of the right eye for 3,854 children aged 6 to 12 who attended our ophthalmology department from 2016 to 2023. We analyzed the average refractive error and myopia prevalence by year and subsequently performed a subgroup analysis by dividing the children into two age groups: 6-9 years old and 10-12 years old. To provide insight into long-term trends, data from 4,351 subjects aged 6-12 years from the 4th, 5th (2008-2012), and 7th (2016) Korea National Health and Nutrition Examination Surveys were also analyzed for reference. Results: The mean refractive error for subjects visiting our clinic throughout the study period was -1.51 ± 2.12 D. A trend of increasing myopic values in refractive error was observed from 2017 to 2021, with a more substantial change noted in 2020 compared to other years, though not reaching statistical significance. In the subgroup analysis, the change in refractive error for the 6-9-year-old group was more pronounced in 2020 but did not reach statistical significance, and no specific trend was identified in the 10-12-year-old group. Myopia prevalence exhibited a consistent increase since 2019 in the 6-9 age group, with a higher proportion of moderate myopia in 2020 compared to previous years. Conversely, no distinct trend was observed in the 10-12-year-old group. Conclusions Although statistical significance was not reached, it appears that the increase in indoor activities due to COVID-19 had an impact on the changes in refractive values for elementary school children, especially in the lower grades of elementary school in 2020.

BACKGROUND AND OBJECTIVES: Little evidence is available on the optimal antithrombotic therapy following percutaneous coronary intervention (PCI) in patients with atrial fibrillation (AF). We investigated the outcomes of antithrombotic treatment strategies in AF patients who underwent PCI. SUBJECTS AND METHODS: Three hundred sixty-two patients (68.0% men, mean age: 68.3+/-7.8 years) with AF and who had undergone PCI with stent implantation between 2005 and 2007 were enrolled. The clinical, demographic and procedural characteristics were reviewed and the stroke risk factors as well as antithrombotic regimens were analyzed. RESULTS: The accompanying comorbidities were as follows: hypertension (59.4%), diabetes (37.3%) and congestive heart failure (16.6%). The average number of stroke risk factors was 1.6. At the time of discharge after PCI, warfarin was prescribed for 84 patients (23.2%). Cilostazol was used in addition to dual antiplatelet therapy in 35% of the patients who did not receive warfarin. The mean follow-up period was 615+/-385 days. The incidences of major adverse cardiac events (MACE), stroke and major bleeding were 11.3%, 3.6% and 4.1%, respectively. By Kaplan-Meier survival analysis, warfarin treatment was not associated with a lower risk of MACE (p=0.886), but it was associated with an increased risk of major bleeding (p=0.002). CONCLUSION: Oral anticoagulation therapy after PCI may increase hemorrhagic events in Korean AF patients.
Angioplasty ; Anticoagulants ; Atrial Fibrillation ; Comorbidity ; Follow-Up Studies ; Heart Failure ; Hemorrhage ; Humans ; Hypertension ; Incidence ; Male ; Percutaneous Coronary Intervention ; Platelet Aggregation Inhibitors ; Risk Factors ; Stents ; Stroke ; Tetrazoles ; Warfarin

BACKGROUND AND OBJECTIVES: While pulmonary vein isolation (PVI) is an effective curative procedure for patients with atrial fibrillation (AF), pulmonary vein (PV) stenosis is a potential complication which may lead to symptoms that are often unrecognized. The aim of this study was to compare differences between ablation sites in pulmonary venous flow (PVF) measured by transthoracic Doppler echocardiography (TTE) before and after PVI. SUBJECTS AND METHODS: One hundred five patients (M : F=64 : 41; mean age 56+/-10 years) with paroxysmal AF (n=78) or chronic, persistent AF (n=27) were enrolled. PVI strategies consisted of ostial ablation (n=75; OA group) and antral ablation using an electroanatomic mapping system (n=30; AA group). The ostial diameter was estimated by magnetic resonance imaging (MRI) in patients with PVF > or =110 cm/sec by TTE after PVI. RESULTS: No patient complained of PV stenosis-related symptoms. Changes in mean peak right PV systolic (-6.7+/-28.1 vs. 10.9+/-25.9 cm/sec, p=0.038) and diastolic (-4.1+/-17.0 vs. 9.9+/-25.9 cm/sec, p=0.021) flow velocities were lower in the AA group than in the OA group. Although the change in mean peak systolic flow velocity of the left PV before and after PVI in the AA group was significantly lower than the change in the OA group (-13.4+/-25.1 vs. 9.2+/-22.3 cm/sec, p=0.016), there was no difference in peak diastolic flow velocity. Two patients in the OA group had high PVF velocities (118 cm/sec and 133 cm/sec) on TTE, and their maximum PV stenoses measured by MRI were 62.5% and 50.0%, respectively. CONCLUSION: PV stenosis after PVI could be detected by TTE, and PVI by antral ablation using an electroanatomic mapping system might be safer and more useful for the prevention of PV stenosis.
Atrial Fibrillation ; Carbamates ; Catheter Ablation ; Catheters ; Constriction, Pathologic ; Echocardiography ; Echocardiography, Doppler ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Organometallic Compounds ; Pulmonary Veins

BACKGROUND AND OBJECTIVES: It has been demonstrated that the concentration of plasma nerve growth factor (NGF) effects nerve sprouting. In addition, the relationship between plasma NGF concentration and the occurrence of ventricular tachyarrhythmia (VT) has been reported in animal models of myocardial infarction (MI). However, the causal relationship between NGF and VT remains unclear in humans. The aim of the current study was to determine whether NGF is increased in patients with MI. In addition, the relationship between the concentration of plasma NGF and the inducibility of VT was evaluated. SUBJECTS AND METHODS: We studied 15 patients with stable angina pectoris (SA) and 30 patients with an acute MI (AMI). The patients in the AMI group were divided into VT occurrence (n=14) and non-VT occurrence groups (n=16). Thirty-four patients suspected to have VT underwent programmed electrical stimulation (PES) and were divided into an idiopathic VT group (n=24) and an induced VT with PES {healthy control (C) group; n=10}. Plasma NGF concentrations were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The plasma concentrations of the AMI group were significantly increased compared to the C group {median (interquartile range), 18.9 (8.7) vs. 10.3 (12.5) pg/mL, p<0.05} and the patients with SA {18.9 (8.7) vs. 15.1 (6.7) pg/mL, p<0.05}, but not significantly different from those in the idiopathic VT group {median (interquartile range), 18.9 (8.7) vs. 18.7 (8.5) pg/mL, p=0.89}. There was no significant difference in the plasma NGF concentrations between the C and SA groups {10.3 (12.5) vs. 15.1 (6.7) pg/mL, p=0.18}. In the AMI patients, there was no significant difference in the plasma NGF concentrations between patients with VT and those without VT {18.5 (6.7) vs. 21.2 (10.2) pg/mL, p=0.25}. CONCLUSION: The plasma NGF concentrations were increased in patients with an AMI compared to patients with SA and Cs.
Angina, Stable ; Electric Stimulation ; Enzyme-Linked Immunosorbent Assay ; Humans ; Models, Animal ; Myocardial Infarction ; Nerve Growth Factor ; Plasma ; Tachycardia

BACKGROUND AND OBJECTIVES: It is known that angiotensin converting enzyme inhibitors and angiotensin II type 1 receptor blockers (ACEIs and ARBs, respectively) are effective in preventing atrial fibrillation (AF) in high-risk patients. However, it is not known whether ACEIs and ARBs are effective in preventing the recurrence of AF after catheter ablation. SUBJECTS AND METHODS: One hundred fifty-two patients (mean age, 57+/-10 years; M : F=94 : 58) who underwent catheter ablation due to drug-refractory paroxysmal (mean age, 57+/-10 years; M : F=58 : 43) or persistent AF (mean age, 56+/-10 years; M : F=36 : 15) were enrolled. We compared the recurrence rates between the groups with and without ACEIs or ARBs use in paroxysmal and persistent AF. The mean duration of follow-up was 18+/-14 months. RESULTS: The overall recurrence rate after ablation therapy was 26% (n=39). The recurrence rate was significantly decreased in the patients with persistent AF with the use of ACEIs or ARBs (12.1% vs. 61.1%, p<0.01), but this difference was not observed in the patients with paroxysmal AF (24.2% vs. 22.9%, p=0.87). In patients with persistent AF with and without recurrence, the size of the left atrium (44.2+/-8.4 mm vs. 44.3+/-5.8 mm, respectively, p=0.45) and the ejection fraction (62+/-6.5% vs. 61.5+/-6.2%, respectively, p=0.28) were not significantly different. In multivariate analysis, the use of ACEIs or ARBs was independently associated with recurrence after adjusting for the size of the left atrium and the ejection fraction {odds ratio (OR)=0.078, 95% confidence interval (CI)=0.02-0.35, p<0.01}. CONCLUSION:ACEIs and ARBs were shown to be effective in preventing AF recurrence after catheter ablation in patients with persistent AF.
Angiotensin II Type 1 Receptor Blockers ; Angiotensin-Converting Enzyme Inhibitors ; Angiotensins ; Atrial Fibrillation ; Catheter Ablation ; Follow-Up Studies ; Heart Atria ; Humans ; Multivariate Analysis ; Peptidyl-Dipeptidase A ; Recurrence

BACKGROUND: Coronary artery disease (CAD) has recently become one of the major causes of mortality and morbidity in Korea. However, not much epidemiologic and demographic data has yet been reported. The purpose of this study was to investigate the clinical features as well as the prognostic factors of patients with CAD. METHODS: We prospectively enrolled 1,665 consecutive patients with CAD who had been admitted to the Catholic University Hospitals from December 1999 to April 2003. RESULTS: Acute myocardial infarction (AMI) was the most common cause of admission (n=715, 42.9%). Dyslipidemia, hypertension and smoking were the most common risk factors. More than 70% of the patients who underwent percutaneous coronary intervention (PCI) received stent implantation. A total of 965 (612 males) patients were followed at least for 6 months (the mean follow-up duration was 23.8+/-12.2 months). The incidence rates of major adverse cardiac events (MACE: cardiac death, acute myocardial infarction, target vessel revascularization) and cardiac death were 15.1% (n=146) and 2.2% (n=21), respectively. There was no difference in overall survival between the patients treated with medical therapy and those treated with PCI. By Cox regression analysis, the independent prognostic factors for MACE were PCI (95% CI: 1.75-4.85; p<0.01) and multivessel disease (95% CI: 1.03-2.04; p<0.05), and the independent prognostic factors for cardiac death were medical therapy (95% CI: 1.08-14.41; p<0.05) and old age (95% CI: 1.13-16.13; p<0.05). CONCLUSIONS: There was no difference in overall survival between the patients treated with medical therapy and those treated with PCI. However, PCI was superior to medical therapy for preventing death of the patients with acute coronary syndrome.
Acute Coronary Syndrome ; Coronary Artery Disease* ; Coronary Disease ; Coronary Vessels* ; Death ; Dyslipidemias ; Follow-Up Studies ; Heart* ; Hospitals, University ; Humans ; Hypertension ; Incidence ; Korea ; Mortality ; Myocardial Infarction ; Percutaneous Coronary Intervention ; Prognosis ; Prospective Studies ; Risk Factors ; Smoke ; Smoking ; Stents

BACKGROUND AND OBJECTIVES: Myocardial infarction (MI) elicits nerve sprouting. However, the time course and spatial distribution of this nerve sprouting and its relationship to the expression of neurotrophic factors is unclear. The aim of this study was to identify the association of nerve sprouting with the expression of neurotrophic factors. MATERIALS AND METHODS: We induced MI in FVB mice by ligating the left coronary artery. The hearts were removed at 3 hours to 13 months after MI for growth associated protein 43 (GAP-43) immunostaining. The nerve density (micrometer2/mm2) was determined by ImagePro software. In another group of mice, their myocardial tissues were processed and analyzed with using an Affymetrix RG U74V2 array. RESULTS: The density of the nerve fibers that were immunopositive for GAP-43 was the highest 3 hours after MI in both the peri-infarct areas and the remote areas. The outer loop of the ventricle had a higher nerve density than that in the inner loop of the ventricle. The differences were at a peak 3 hours after MI, but they persisted for 2 months afterwards. The expressions of nerve growth factor, insulin-like growth factor, leukemia inhibitory factor, transforming growth factor-beta3 and interleukin-1alpha were increased for up to 2 months after MI as compared to the normal control. qRT PCR analyses showed increased mRNA for tyrosine hydroxylase, synaptophysin, nerve growth factor and leukemia inhibiting factor in the peri-infarct areas for up to 2 months after MI, but this occurred only for roughly 3 days after MI in the remote areas. CONCLUSION: We conclude that MI resulted in immediate upregulation of nerve growth factor, insulin-like growth factor, leukemia inhibitory factor, transforming growth factor-beta3 and interleukin-1alpha in the peri-infarct areas and this all occurred to a lesser extent in the remote areas. These changes persisted for at least 2 months, and they were associated with increased nerve sprouting activity, which was most active in the outer loop of the heart.
Animals ; Coronary Vessels ; DNA ; Electrophysiology ; GAP-43 Protein ; Heart ; Interleukin-1alpha ; Leukemia ; Leukemia Inhibitory Factor ; Mice* ; Myocardial Infarction* ; Nerve Fibers ; Nerve Growth Factor ; Nerve Growth Factors ; Polymerase Chain Reaction ; Regeneration ; RNA, Messenger ; Synaptophysin ; Tyrosine 3-Monooxygenase ; Up-Regulation ; Ventricular Remodeling

PURPOSE: We evaluated the imaging abnormalities of the brain observed during and after treatment of acute childhood lymphoblastic leukemia. MATERIALS AND METHODS: The study group consisted of 30patients (male: female= 19:11; mean age, 64months) with acute childhood lymphoblastic leukemia during the previous ten-year period who had undergone pro-phylaxis of the central nervous system. Irrespective of the CNS symptoms, baseline study of the brain involving CT and follow-up CT or MRI was undertaken more than once. We retrospectively evaluated the imaging findings, methods of treatment, associated CNS symptoms, and the interval between diagnosis and the time at which brain abnormalities were revealed by imaging studies. RESULTS: In 15 (50% ; male : female=9:6 ; mean age, 77months) of 30 patients, brain abnormalities that included brain atrophy (n=9), cerebral infarctions (n=4), intracranial hemorrhage (n=1), mineralizing microangiopathy (n=2), and periventricular leukomalacia (n=3) were seen on follow-up CT or MR images. In four of nine patients with brain atrophy, imaging abnormalities such as periventricular leukomalacia(n=2), infarction (n=1) and microangiopathy (n=1) were demonstrated. Fourteen of the 15 patients underwent similar treatment; the one excluded had leukemic cells in the CSF. Six patients had CNS symptoms. In the 15 patients with abnormal brain imaging findings, the interval between diagnosis and the demonstration of brain abnormalities was between one month and four years. After the cessation of treatment, imaging abnormalities remained in all patients except one with brain atrophy. CONCLUSION: Various imaging abnormalities of the brain may be seen during and after the treatment of acute childhood lymphoblastic leukemia and persist for a long time. In children with this condition, the assessment of brain abnormalities requires follow-up study of the brain.
Atrophy ; Brain* ; Central Nervous System ; Cerebral Infarction ; Child* ; Diagnosis ; Follow-Up Studies ; Humans ; Infant, Newborn ; Infarction ; Intracranial Hemorrhages ; Leukomalacia, Periventricular ; Magnetic Resonance Imaging ; Male ; Neuroimaging ; Precursor Cell Lymphoblastic Leukemia-Lymphoma* ; Retrospective Studies ; Withholding Treatment

BACKGROUND: Heart transplantation is a definite treatment modality of the patients with end-stage heart failure. Heart transplantation has been performed in Korea since 1992, and currently it is an established procedure for the management of terminal heart failure. The purpose of this study is to clarify the Korean status of heart transplantation. METHODS: Six major heart transplantation centers' 137 cases during the period November 1992 through May 1999 are analyzed to evaluate the general demographics, underlying heart diseases, postoperative management, complications, and survival. RESULTS: The mean age of the patients is 37 years old, and the mean follow-up period is 25 months (1 day - 80 months, median 20 months). Most common underlying disease related to heart failure is cardiomyopathy (86%). Total 16% of patients underwent cellular rejection of ISHLT (International Society of Heart and Lung Transplantation) grade 3A or more within 1 year after transplantation. The most common type of clinical infection is bacterial (18%), and the most common organism is Herpes zoster virus (6.4%). Graft coronary artery disease examined by coronary angiography detected in 3.7% of recipients within 12 months after transplantation. One, 2, 3, and 5-year overall survival rates of recipients are 81% , 72%, 71%, and 62%, respectively. CONCLUSION: Distribution of underlying heart diseases and the frequency of graft coronary artery disease of Korean heart transplantation recipients were different from those of the western patients. Although the history of heart transplantation in Korea is relatively short, the early and long-term results are comparable with well-established centers.
Adult ; Cardiomyopathies ; Coronary Angiography ; Coronary Artery Disease ; Demography ; Follow-Up Studies ; Heart Diseases ; Heart Failure ; Heart Transplantation* ; Heart* ; Herpesvirus 3, Human ; Humans ; Korea* ; Lung ; Survival Rate ; Transplants

BACKGROUND: little is known about the mechanisms responsible for ventricular tachycardia during myocardial ischemia and reperfusion. The purpose of this study was to evaluate the effects of the autonomic nervous system on ventricular tachycardia in dogs. METHODS: Four groups of eight dogs were studied. The control group had intact autonomic neural innervation:the stellectomy group had bilateral transection of stellate ganglia:the vagotomy group had bilateral transection of cervical vagi; and the autonomic denervation group underwent bilateral transection of stellate ganglia and cervical vagi. Open-chest dogs anesthetized with ketamine were studied in 3 sequential steps: denervation, ischemia, and reperfusion stage. At the end of each step, we estimated effective refractory period (ERP) at four sites : the apex of non-ischemic area, the base of non-ischemic area, the apex of ischemic area, and the base of ischemic area. We observed early afterdepolarization (EAD) through recording monophasic action potential on the ischemic epicardium during ischemia and reperfusion stages. RESULTS: In ischemia stage, deltaERPs(ERPmax.-ERPmin.) were significantly prolonged, compared to deltaERPs at denervation stage, and deltaERPs of the vagotomy group tended to be prolonged to 60 minutes after myocardial ischemia, as compared to those of the stellectomy group and the autonomic denervation group. The incidence of ventricular tachycardia during ischemia presented a significant increase in the vagotomy group, compared to the control group. However, there was no difference in incidence of ventricular tachycardia between the stellectomy group and the control group. deltaERP at the group with the occurrence of ventricular tachycardia were significantly prolonged , compared to the other group without the occurrence of ventricular tachycardia. In terms of the incidence of EAD, there was no difference between the groups and it was not associated with ventricular tachycardia. deltaERP was significantly decreased to 30 minutes after reperfusion, at which point there was no significant difference between the groups. There was no correlation between EAD and ventricular tachycardia. However, deltaERP with ventricular tachycardia indicated much more significant increase than deltaERP without ventricular tachycardia. CONCLUSIONS: Sympathetic nerve may be related to prolongation of deltaERP and incidence of ventricular tachycardia in the ischemic period. However, EAD is not related to ventricular tachycardia during ischemia and reperfusion. These findings suggest that the major mechanism of ventricular tachycardia may be a reentry in ischemia and reperfusion period.
Action Potentials ; Animals ; Autonomic Denervation* ; Autonomic Nervous System ; Denervation ; Dogs ; Heart* ; Incidence ; Ischemia* ; Ketamine ; Myocardial Ischemia ; Pericardium ; Reperfusion* ; Stellate Ganglion ; Tachycardia* ; Tachycardia, Ventricular ; Vagotomy