Background: The objective of this study was to evaluate the efficacy and safety of totally thoracoscopic ablation (TTA) in patients with recurrent atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA). Methods: From February 2012 to May 2020, 460 patients who underwent TTA were classified into two groups: CA (presence of RFCA history, n = 74) and nCA groups (absence of RFCA history, n = 386). Inverse probability of treatment weighting (IPTW) analyses were used to adjust for confounders. The primary endpoint was freedom from the composite of AF, typical atrial flutter, atypical atrial flutter and any atrial tachyarrhythmia, lasting more than 30 seconds during the follow-up. All patients were followed up at 3, 6, and 12 months via electrocardiogram and 24-hour Holter monitoring. Results: Bilateral pulmonary vein isolation (PVI) was conducted in all patients and the conduction block tests were confirmed. In the CA group, difficult PVI occasionally occurred due to structural changes, such as pericardial adhesion and fibrosis of the pulmonary venous structure, caused by a previous catheter ablation. Early complications such as stroke and pacemaker insertion were not different between the two groups. The normal sinus rhythm was maintained in 70.1% (317/460) patients after a median follow-up period of 38.1 months.The IPTW-weighted Kaplan-Meier curves revealed that freedom from AF events at 5 years was 68.4% (95% confidence interval, 62.8–74.5) in the nCA group and 31.2% (95% confidence interval, 16.9–57.5) in the CA group (P < 0.001). In IPTW-weighted Cox regression, preoperative left atrial diameter, persistent or long-standing AF, the presence of congestive heart failure and catheter ablation history were associated with AF events. Conclusion Patients in the CA group showed a higher recurrence rate of AF than those in the nCA group, while TTA was safely performed in both the groups.

Cancer organoids are three-dimensional mini-organ analogues derived from cancer tissues and have been proposed as models capable of simulating the structure and function of human organs and tissues in vitro. We sought to establish gastric cancer patient-derived organoids (PDOs) from tissues obtained by endoscopic biopsies. Gastric cancer-PDOs were successfully established and cultured from cancer tissues with gastric adenocarcinoma by endoscopic biopsies. To confirm that gastric cancer-PDOs were derived from cancer tissue, the consistency of the original cancer tissue was assessed by histopathological examination.As a result, it was confirmed that the shape and internal structure of gastric cancer-PDO were derived from the original gastric cancer cells, and the tumor specificity of gastric cancerPDO was confirmed through Periodic acid-Schiff (PAS) and polyclonal carcinoembryonic antigen antibody staining. These results demonstrate that gastric cancer-PDO models show the characteristics of primary tumors and have potential for drug screening and providing a personalized medicine platform.

PURPOSE: Though regular surveillance of hepatocellular carcinoma (HCC) for high-risk patients is widely recommended, its rate and effectiveness are not clear. The aim of this study is to investigate the actual rate of HCC surveillance and its related factors and to clarify its impact on survival in a Korean HCC cohort. MATERIALS AND METHODS: From 2012 to 2015, 319 newly diagnosed HCC patients were prospectively enrolled at a tertiary hospital. Patient interviews based on a structured questionnaire survey were conducted. Surveillance was defined as liver imaging test ≥ 2 times with at least 3-month interval within 2 years prior to HCC diagnosis. RESULTS: Surveillance rate was 39.8%. Of the HCC patients with high-risk factors, only 182 (57.1%) had knowledge for the need for regular surveillance, and 141 (44.2%) had the accurate information about the method (ultrasound-based study). Surveillance group showed a higher proportion of early HCC (p < 0.001) and a longer overall survival (p < 0.001) compared to non-surveillance group. The multivariable Cox regression analysis indicated Child-Pugh class A, history of anti-viral therapy, low serum α-fetoprotein level, non-advanced Barcelona Clinic Liver Cancer stage as independent predictors of overall survival, while regular surveillance was not (p=0.436). CONCLUSION: Less than half of the newly diagnosed Korean HCC patients were under surveillance and the accurate perception for the need of HCC surveillance was insufficient. Of those under surveillance, most patients were diagnosed with early stage HCC, which led to the improved survival. Comprehensive efforts to optimize the surveillance program for the target population are warranted.
Carcinoma, Hepatocellular ; Cohort Studies ; Diagnosis ; Health Services Needs and Demand ; Humans ; Korea ; Liver ; Liver Cirrhosis ; Liver Neoplasms ; Mass Screening ; Methods ; Prospective Studies ; Tertiary Care Centers

Tumor undergo uncontrolled, excessive proliferation leads to hypoxic microenvironment. To fulfill their demand for nutrient, and oxygen, tumor angiogenesis is required. Endothelial progenitor cells (EPCs) have been known to the main source of angiogenesis because of their potential to differentiation into endothelial cells. Therefore, understanding the mechanism of EPC-mediated angiogenesis in hypoxia is critical for development of cancer therapy. Recently, mitochondrial dynamics has emerged as a critical mechanism for cellular function and differentiation under hypoxic conditions. However, the role of mitochondrial dynamics in hypoxia-induced angiogenesis remains to be elucidated. In this study, we demonstrated that hypoxia-induced mitochondrial fission accelerates EPCs bioactivities. We first investigated the effect of hypoxia on EPC-mediated angiogenesis. Cell migration, invasion, and tube formation was significantly increased under hypoxic conditions; expression of EPC surface markers was unchanged. And mitochondrial fission was induced by hypoxia time-dependent manner. We found that hypoxia-induced mitochondrial fission was triggered by dynamin-related protein Drp1, specifically, phosphorylated DRP1 at Ser637, a suppression marker for mitochondrial fission, was impaired in hypoxia time-dependent manner. To confirm the role of DRP1 in EPC-mediated angiogenesis, we analyzed cell bioactivities using Mdivi-1, a selective DRP1 inhibitor, and DRP1 siRNA. DRP1 silencing or Mdivi-1 treatment dramatically reduced cell migration, invasion, and tube formation in EPCs, but the expression of EPC surface markers was unchanged. In conclusion, we uncovered a novel role of mitochondrial fission in hypoxia-induced angiogenesis. Therefore, we suggest that specific modulation of DRP1-mediated mitochondrial dynamics may be a potential therapeutic strategy in EPC-mediated tumor angiogenesis.
Anoxia ; Cell Movement ; Endothelial Cells ; Endothelial Progenitor Cells* ; Mitochondrial Dynamics* ; Oxygen ; RNA, Small Interfering

BACKGROUND AND OBJECTIVES: Success rates of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have recently been reported to range from 80% to 90%. A better understanding of the pathologic characteristics of the CTO lesion may helpful to improving CTO PCI success rates. We evaluated the CTO lesion in patients with stable angina (SA) by virtual histology-intravascular ultrasound (VH-IVUS). SUBJECTS AND METHODS: The study population consisted of 149 consecutive patients with SA underwent VH-IVUS examination. We analyzed demographic and VH-IVUS findings in 22 CTO patients (17 males; mean, 62.3 years old) compared with 127 non-CTO patients (82 males; mean, 61.3 years old). RESULTS: A significantly lower ejection fraction (57.6+/-13.0% vs. 65.4+/-8.8%, p=0.007) was detected in the CTO group compared with the non-CTO group. Reference vessel lumen area of the proximal and distal segment was significantly less in CTO group than in non-CTO group. The lesion length of the CTO group was significantly longer than those of the non-CTO group (24.4+/-9.6 mm vs. 17.2+/-7.4 mm, p<0.001). Total atheroma volume (224+/-159 mm3 vs. 143+/-86 mm3, p=0.006) and percent atheroma volume (63.2+/-9.6% vs. 55.8+/-8.5%, p=0.011) of the CTO group were also significantly greater than those of non-CTO group. However, the lesion length adjusted plaque composition of the CTO group was not significantly different compared with that of the non-CTO group. CONCLUSION: CTO lesions had a longer lesion length and greater plaque burden than the non-CTO lesion in patients with SA. However, lesion length adjusted plaque composition showed similar between the two groups. These results support that plaque characteristics of CTO lesions are similar to non-CTO lesions in patients with SA.
Angina Pectoris ; Angina, Stable ; Humans ; Male ; Percutaneous Coronary Intervention ; Plaque, Atherosclerotic ; Ultrasonography* ; Ultrasonography, Interventional

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of ear infections. We attempted to evaluate the clinical usefulness of arbekacin in treating chronic suppurative otitis media (CSOM) by comparing its clinical efficacy and toxicity with those of vancomycin. Efficacy was classified according to bacterial elimination or bacteriologic failure and improved or failed clinical efficacy response. Ninety-five subjects were diagnosed with CSOM caused by MRSA. Twenty of these subjects were treated with arbekacin, and 36 with vancomycin. The bacteriological efficacy (bacterial elimination, arbekacin vs. vancomycin: 85.0% vs. 97.2%) and improved clinical efficacy (arbekacin vs. vancomycin; 90.0% vs. 97.2%) were not different between the two groups. However, the rate of complications was higher in the vancomycin group (33.3%) than in the arbekacin group (5.0%) (P=0.020). In addition, a total of 12 adverse reactions were observed in the vancomycin group; two for hepatotoxicity, one for nephrotoxicity, eight for leukopenia, two for skin rash, and one for drug fever. It is suggested that arbekacin be a good alternative drug to vancomycin in treatment of CSOM caused by MRSA.
Adult ; Aged ; Anti-Bacterial Agents/administration & dosage ; Chronic Disease ; Dibekacin/administration & dosage/*analogs & derivatives ; Female ; Humans ; Male ; Methicillin-Resistant Staphylococcus aureus/*drug effects ; Middle Aged ; Otitis Media, Suppurative/diagnosis/*drug therapy/microbiology ; Staphylococcal Infections/diagnosis/*drug therapy/microbiology ; Treatment Outcome ; Vancomycin/*administration & dosage ; Young Adult

BACKGROUND AND OBJECTIVES: We assessed the ability of portable echocardiography (with contrasts) to clearly delineate the cardiac structure, and evaluated the impact of its use on the diagnosis and management of critically ill patients in Korea. SUBJECTS AND METHODS: We prospectively enrolled 123 patients (mean age 66+/-16 years), who underwent portable transthoracic echocardiography (with contrast) for image enhancement at 12 medical centers. The quality of the global left ventricular (LV) images, the number of the regional LV segments visualized, the ability to visualize the LV apex and the right ventricle (RV), and any changes in the diagnostic procedure and treatment strategy were compared before and after the contrast. RESULTS: Of the 123 patients, 52 (42%) were using mechanical ventilators. The amount of poor or uninterpretable images decreased from 48% to 5% (p<0.001), after the contrast. Before the contrast, 15.6+/-1.1 of 16 LV segments were seen, which improved to 15.9+/-0.6 segments (p=0.001) after the contrast. The ability to visualize the LV apex increased from 47% to 94% (p<0.001), while the inability to clearly visualize the RV decreased from 46% to 19% (p<0.001). Changes in the diagnostic procedure (for example, not requiring other types of imaging studies) were observed in 18% of the patients, and the treatment plan (medication) was altered in 26% of patients after the contrast echocardiography. CONCLUSION: The use of a contrast agent during the portable echocardiography, in intensive care settings, can improve the image quality and impact the diagnostic procedures and treatment for Korean patients.
Critical Illness ; Diagnosis ; Echocardiography* ; Heart Ventricles ; Humans ; Image Enhancement ; Critical Care* ; Korea ; Prospective Studies ; Ventilators, Mechanical

Acute cholecystitis is a rare complication of scrub typhus. Although a few such cases have been reported in patients with scrub typhus, the clinical course is not well described. Of 12 patients, acute cholecystitis developed in 66.7% (8/12) of patients older than 60 yr. The scrub typhus group with acute cholecystitis had marginal significant longer hospital stay and higher cost than the group without cholecystitis according to propensity score matching. Scrub typhus should be kept in mind as a rare etiology of acute cholecystitis in endemic areas because the typical signs of scrub typhus such as skin rash and eschar can present after the abdominal pain.
Aged ; Aged, 80 and over ; Cholecystitis, Acute/*diagnosis/*etiology/therapy ; Diagnosis, Differential ; Female ; Humans ; Male ; Republic of Korea ; Scrub Typhus/*complications/*diagnosis/therapy ; Treatment Outcome

BACKGROUND AND OBJECTIVES: Hypercholesterolemia is a key factor in the development of atherosclerosis. We sought to evaluate the relation between hypercholesterolemia and plaque composition in patients with coronary artery disease. SUBJECTS AND METHODS: Study subjects consisted of 323 patients (mean 61.5 years, 226 males) who underwent coronary angiography and virtual histology-intravascular ultrasound examination. Patients were divided into two groups according to total cholesterol level: hypercholesterolemic group (> or =200 mg/dL, n=114) and normocholesterolemic group (<200 mg/dL, n=209). RESULTS: Hypercholesterolemic patients were younger (59.7+/-13.3 years vs. 62.6+/-11.5 years, p=0.036), than normocholesterolemic patients, whereas there were no significant differences in other demographics. Hypercholesterolemic patients had higher corrected necrotic core volume (1.23+/-0.85 mm3/mm vs. 1.02+/-0.80 mm3/mm, p=0.029) as well as percent necrotic core volume (20.5+/-8.5% vs. 18.0+/-9.2%, p=0.016) than normocholesterolemic patients. At the minimal lumen area site, percent necrotic core area (21.4+/-10.5% vs. 18.4+/-11.3%, p=0.019) and necrotic core area (1.63+/-1.09 mm2 vs. 1.40+/-1.20 mm2, p=0.088) were also higher than normocholesterolemic patients. Multivariate linear regression analysis showed that total cholesterol level was an independent factor of percent necrotic core volume in the culprit lesion after being adjusted with age, high density lipoprotein-cholesterol , hypertension, diabetes mellitus, smoking and acute coronary syndrome (beta 0.027, 95% confidence interval 0.02-0.053, p=0.037). CONCLUSION: Hypercholesterolemia was associated with increased necrotic core volume in coronary artery plaque. This study suggests that hypercholesterolemia plays a role in making plaque more complex, which is characterized by a large necrotic core, in coronary artery disease.
Acute Coronary Syndrome ; Atherosclerosis ; Cholesterol ; Coronary Angiography ; Coronary Artery Disease ; Coronary Vessels ; Demography ; Diabetes Mellitus ; Humans ; Hypercholesterolemia ; Hypertension ; Linear Models ; Smoking

BACKGROUND AND OBJECTIVES: We evaluated which plaque components are associated with long-term clinical events in patients who underwent primary percutaneous coronary intervention (PCI). SUBJECTS AND METHODS: The study subjects consisted of 57 consecutive patients (mean age, 58.5+/-14.5 years; 45 males) who underwent primary PCI and a virtual histology-intravascular ultrasound examination. Major adverse cardiac events (MACEs) including death, acute myocardial infarction, stroke, and revascularization were evaluated during the mean 28 month follow-up period. RESULTS: Patients with high fibro-fatty volume (FFV >13.4 mm3, n=29; mean age, 61.3 years) had a lower ejection fraction (52.7% vs. 59.4%, p=0.022), a higher incidence of multi-vessel disease (69.0% vs. 28.6%, p=0.002), larger plaque area (25.7 mm2 vs. 15.9 mm2, p<0.001), and larger plaque volume (315 mm3 vs. 142 mm3, p<0.001) than those with a low FFV (< or =13.4 mm3, n=28; mean age, 55.6 years). Patients with high FFV had a significantly higher incidence (32.1% vs. 8.3%, p=0.036) of MACE than those with low FFV. When we divided the study population according to the necrotic core volume (NCV), fibrous volume, or dense calcified volume, no significant findings in terms of demographics and MACE rates were observed. A Cox regression analysis revealed that the independent factor for MACE was FFV (hazard ratio, 6.748; 95% confidence interval, 1.168-38.971, p=0.033) in this study population. CONCLUSION: The coronary plaque component, particularly FFV, but not NCV, was important in long-term clinical outcomes in patients who underwent primary PCI.
Demography ; Disease-Free Survival ; Follow-Up Studies ; Humans ; Incidence ; Myocardial Infarction ; Percutaneous Coronary Intervention ; Stroke ; Ultrasonography, Interventional