1.Nationwide Survey on Endoscopic Submucosal Dissection for Early Gastric Cancer in Korea: Results From the Korean College of Helicobacter and Upper Gastrointestinal Research (KCHUGR) 2023 Survey
Jae Yong PARK ; Jeong Hoon LEE ; Tae-Se KIM ; Da Hyun JUNG ; Bong Eun LEE ; Yonghoon CHOI ; Wan-Sik LEE ; Young-Il KIM ; Sun Hyung KANG ; Hyunsoo CHUNG ; Su Jin KIM ; Joon Sung KIM ; Donghoon KANG ; Su Youn NAM ; Seung Han KIM ; Hyo-Joon YANG ; Hyun LIM ; Jin LEE ; Seon-Young PARK ; Seung-Woo LEE ; Sun Moon KIM ; Sam Ryong JEE ; Dae Young CHEUNG ; Chung Hyun TAE ; Seokin KANG ; Sung Chul PARK ; Seung In SEO ; Cheol Min SHIN ; Kee Don CHOI ; Jong Yeul LEE ;
Journal of Gastric Cancer 2026;26(2):169-183
Purpose:
Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research.
Materials and Methods:
Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes.Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes.
Results:
Data from 5,460 ESD cases from 5,250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days.
Conclusions
This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.
2.Detection and prognostic stratification of left ventricular systolic dysfunction in left bundle branch block using an artificial intelligence–enabled electrocardiography
Soo Youn LEE ; Ah‑Hyun YOO ; Sora KANG ; Jong‑Hwan JANG ; Yong‑Yeon JO ; Jeong Min SON ; Min Sung LEE ; Ga In HAN ; Joon‑myoung KWON ; Hak Seung LEE ; Kyung‑Hee KIM
Journal of Cardiovascular Imaging 2026;34(1):4-
Background:
Left bundle branch block (LBBB) significantly increases the risk of left ventricular systolic dysfunction (LVSD) due to cardiac dyssynchrony. Although artificial intelligence–enabled electrocardiography (AI-ECG) mod‑ els show promise in detecting LVSD, their performance in LBBB patients remains underexplored. We hypothesized that an AI-ECG model clinically validated for detecting LVSD would accurately detect LVSD and predict future clinical outcomes in LBBB patients.
Methods:
In this retrospective multicenter study, 5,689 expert-validated LBBB ECGs collected from 2,813 patients between 2016 and 2024 were analyzed using a previously developed and validated AI-ECG model. LVSD was defined as an ejection fraction of ≤ 40%. Model performance was assessed using the area under the receiver operating char‑ acteristic curve (AUROC), the area under the precision-recall curve (AUPRC), sensitivity, and specificity. Patients were stratified into high- and low-risk groups based on a threshold that achieved 90% sensitivity. A Kaplan–Meier analysis was used to compare clinical outcomes.
Results:
Among the 2,813 LBBB patients (mean age, 70.7 years; male sex, 43.7%), hypertension and a history of heart failure were common. The AiTiALVSD model showed strong diagnostic performance for LVSD (AUROC, 0.930 [95% CI, 0.924–0.937]; AUPRC, 0.913 [95% CI, 0.902–0.923]; sensitivity, 0.979; specificity, 0.473). During the mean follow-up of 4.1 years, high-risk patients had significantly higher hazards than low-risk patients for all-cause mortality (adjusted hazard ratio [HR], 1.87; 95% CI, 1.53–2.28), implantable cardioverter defibrillator/cardiac resynchronization therapy implantation (adjusted HR, 15.2; 95% CI, 7.51–30.77), and cardiovascular hospitalization (adjusted HR, 1.11; 95% CI, 0.96–1.28).
Conclusions
AiTiALVSD effectively detects LVSD and stratifies long-term cardiovascular risk in LBBB patients, support‑ ing its clinical utility for early detection and patient management.
3.Nationwide Survey on Endoscopic Submucosal Dissection for Early Gastric Cancer in Korea: Results From the Korean College of Helicobacter and Upper Gastrointestinal Research (KCHUGR) 2023 Survey
Jae Yong PARK ; Jeong Hoon LEE ; Tae-Se KIM ; Da Hyun JUNG ; Bong Eun LEE ; Yonghoon CHOI ; Wan-Sik LEE ; Young-Il KIM ; Sun Hyung KANG ; Hyunsoo CHUNG ; Su Jin KIM ; Joon Sung KIM ; Donghoon KANG ; Su Youn NAM ; Seung Han KIM ; Hyo-Joon YANG ; Hyun LIM ; Jin LEE ; Seon-Young PARK ; Seung-Woo LEE ; Sun Moon KIM ; Sam Ryong JEE ; Dae Young CHEUNG ; Chung Hyun TAE ; Seokin KANG ; Sung Chul PARK ; Seung In SEO ; Cheol Min SHIN ; Kee Don CHOI ; Jong Yeul LEE ;
The Korean Journal of Helicobacter and Upper Gastrointestinal Research 2026;26(1):50-59
Objectives:
Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research.
Methods:
Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes. Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes.
Results:
Data from 5460 ESD cases from 5250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days.
Conclusions
This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.
4.Discordance Between Angiographic Assessment and Fractional Flow Reserve or Intravascular Ultrasound in Intermediate Coronary Lesions: A Post-hoc Analysis of the FLAVOUR Trial
Jung-Hee LEE ; Sung Gyun AHN ; Ho Sung JEON ; Jun-Won LEE ; Young Jin YOUN ; Jinlong ZHANG ; Xinyang HU ; Jian’an WANG ; Joo Myung LEE ; Joo-Yong HAHN ; Chang-Wook NAM ; Joon-Hyung DOH ; Bong-Ki LEE ; Weon KIM ; Jinyu HUANG ; Fan JIANG ; Hao ZHOU ; Peng CHEN ; Lijiang TANG ; Wenbing JIANG ; Xiaomin CHEN ; Wenming HE ; Myeong-Ho YOON ; Seung-Jea TAHK ; Ung KIM ; You-Jeong KI ; Eun-Seok SHIN ; Doyeon HWANG ; Jeehoon KANG ; Hyo-Soo KIM ; Bon-Kwon KOO
Korean Circulation Journal 2024;54(8):485-496
Background and Objectives:
Angiographic assessment of coronary stenosis severity using quantitative coronary angiography (QCA) is often inconsistent with that based on fractional flow reserve (FFR) or intravascular ultrasound (IVUS). We investigated the incidence of discrepancies between QCA and FFR or IVUS, and the outcomes of FFR- and IVUS-guided strategies in discordant coronary lesions.
Methods:
This study was a post-hoc analysis of the FLAVOUR study. We used a QCA-derived diameter stenosis (DS) of 60% or greater, the highest tertile, to classify coronary lesions as concordant or discordant with FFR or IVUS criteria for percutaneous coronary intervention (PCI). The patient-oriented composite outcome (POCO) was defined as a composite of death, myocardial infarction, or revascularization at 24 months.
Results:
The discordance rate between QCA and FFR or IVUS was 30.2% (n=551). The QCAFFR discordance rate was numerically lower than the QCA-IVUS discordance rate (28.2% vs. 32.4%, p=0.050). In 200 patients with ≥60% DS, PCI was deferred according to negative FFR (n=141) and negative IVUS (n=59) (15.3% vs. 6.5%, p<0.001). The POCO incidence was comparable between the FFR- and IVUS-guided deferral strategies (5.9% vs. 3.4%, p=0.479).Conversely, 351 patients with DS <60% underwent PCI according to positive FFR (n=118) and positive IVUS (n=233) (12.8% vs. 25.9%, p<0.001). FFR- and IVUS-guided PCI did not differ in the incidence of POCO (9.5% vs. 6.5%, p=0.294).
Conclusions
The proportion of QCA-FFR or IVUS discordance was approximately one third for intermediate coronary lesions. FFR- or IVUS-guided strategies for these lesions were comparable with respect to POCO at 24 months.
5.Impact of COVID-19 pandemic on emergency department visits during daytime and nighttime
Ah Young KIM ; Young-Hoon YOON ; Jung-Youn KIM ; Bosun SHIM ; Sung Joon PARK
Journal of the Korean Society of Emergency Medicine 2024;35(6):413-423
Objective:
There has been a rapid increase in the utilization of emergency departments (EDs), especially for non-emergent cases. The challenges of accessing medical services at night cause disparities in ED utilization between the day and night. Additionally, the coronavirus disease-2019 (COVID-19) pandemic has had a notable impact on ED visits. This study aimed to compare the characteristics of patients visiting the EDs in the daytime and at night before and after COVID-19.
Methods:
A retrospective observational study was conducted on adults (≥18 years) at three metropolitan EDs from January 1, 2019 to December 31, 2020. Data, including the Korean Triage Acuity System, Tenth Revision (ICD-10) codes, and ICU admissions, were collected. Characteristics of patients visiting the ED during the day (06:00-18:00) and night (18:00-06:00) periods before and after COVID-19 were analyzed.
Results:
During the pre-COVID-19 and COVID-19 periods, 117,896 and 92,915 patients visited the ED, respectively. Non-emergency nighttime visits were increased than daytime visits during both the pre-COVID-19 period (37.9% vs. 30.9%) and the COVID-19 period (35.4% vs. 28.8%) (P<0.01). During COVID-19, non-emergency patient visits to the ED during the nighttime decreased compared to those during the day (odds ratio, 0.96; 95% confidence interval [CI], 0.93-0.99, P=0.01). Among the top five diagnoses, the number of patients declined during the COVID-19 pandemic in most categories, except for the category of “Fever of other and unknown origin,” which saw an increase both during the day (incident rate ratio [IRR], 1.10; 95% CI, 1.05-1.17) and night (IRR, 1.23; 95% CI, 1.17-1.30).
Conclusion
The COVID-19 pandemic significantly influenced ED visit patterns, particularly by reducing non-emergent visits during nighttime.
6.Discordance Between Angiographic Assessment and Fractional Flow Reserve or Intravascular Ultrasound in Intermediate Coronary Lesions: A Post-hoc Analysis of the FLAVOUR Trial
Jung-Hee LEE ; Sung Gyun AHN ; Ho Sung JEON ; Jun-Won LEE ; Young Jin YOUN ; Jinlong ZHANG ; Xinyang HU ; Jian’an WANG ; Joo Myung LEE ; Joo-Yong HAHN ; Chang-Wook NAM ; Joon-Hyung DOH ; Bong-Ki LEE ; Weon KIM ; Jinyu HUANG ; Fan JIANG ; Hao ZHOU ; Peng CHEN ; Lijiang TANG ; Wenbing JIANG ; Xiaomin CHEN ; Wenming HE ; Myeong-Ho YOON ; Seung-Jea TAHK ; Ung KIM ; You-Jeong KI ; Eun-Seok SHIN ; Doyeon HWANG ; Jeehoon KANG ; Hyo-Soo KIM ; Bon-Kwon KOO
Korean Circulation Journal 2024;54(8):485-496
Background and Objectives:
Angiographic assessment of coronary stenosis severity using quantitative coronary angiography (QCA) is often inconsistent with that based on fractional flow reserve (FFR) or intravascular ultrasound (IVUS). We investigated the incidence of discrepancies between QCA and FFR or IVUS, and the outcomes of FFR- and IVUS-guided strategies in discordant coronary lesions.
Methods:
This study was a post-hoc analysis of the FLAVOUR study. We used a QCA-derived diameter stenosis (DS) of 60% or greater, the highest tertile, to classify coronary lesions as concordant or discordant with FFR or IVUS criteria for percutaneous coronary intervention (PCI). The patient-oriented composite outcome (POCO) was defined as a composite of death, myocardial infarction, or revascularization at 24 months.
Results:
The discordance rate between QCA and FFR or IVUS was 30.2% (n=551). The QCAFFR discordance rate was numerically lower than the QCA-IVUS discordance rate (28.2% vs. 32.4%, p=0.050). In 200 patients with ≥60% DS, PCI was deferred according to negative FFR (n=141) and negative IVUS (n=59) (15.3% vs. 6.5%, p<0.001). The POCO incidence was comparable between the FFR- and IVUS-guided deferral strategies (5.9% vs. 3.4%, p=0.479).Conversely, 351 patients with DS <60% underwent PCI according to positive FFR (n=118) and positive IVUS (n=233) (12.8% vs. 25.9%, p<0.001). FFR- and IVUS-guided PCI did not differ in the incidence of POCO (9.5% vs. 6.5%, p=0.294).
Conclusions
The proportion of QCA-FFR or IVUS discordance was approximately one third for intermediate coronary lesions. FFR- or IVUS-guided strategies for these lesions were comparable with respect to POCO at 24 months.
7.Impact of COVID-19 pandemic on emergency department visits during daytime and nighttime
Ah Young KIM ; Young-Hoon YOON ; Jung-Youn KIM ; Bosun SHIM ; Sung Joon PARK
Journal of the Korean Society of Emergency Medicine 2024;35(6):413-423
Objective:
There has been a rapid increase in the utilization of emergency departments (EDs), especially for non-emergent cases. The challenges of accessing medical services at night cause disparities in ED utilization between the day and night. Additionally, the coronavirus disease-2019 (COVID-19) pandemic has had a notable impact on ED visits. This study aimed to compare the characteristics of patients visiting the EDs in the daytime and at night before and after COVID-19.
Methods:
A retrospective observational study was conducted on adults (≥18 years) at three metropolitan EDs from January 1, 2019 to December 31, 2020. Data, including the Korean Triage Acuity System, Tenth Revision (ICD-10) codes, and ICU admissions, were collected. Characteristics of patients visiting the ED during the day (06:00-18:00) and night (18:00-06:00) periods before and after COVID-19 were analyzed.
Results:
During the pre-COVID-19 and COVID-19 periods, 117,896 and 92,915 patients visited the ED, respectively. Non-emergency nighttime visits were increased than daytime visits during both the pre-COVID-19 period (37.9% vs. 30.9%) and the COVID-19 period (35.4% vs. 28.8%) (P<0.01). During COVID-19, non-emergency patient visits to the ED during the nighttime decreased compared to those during the day (odds ratio, 0.96; 95% confidence interval [CI], 0.93-0.99, P=0.01). Among the top five diagnoses, the number of patients declined during the COVID-19 pandemic in most categories, except for the category of “Fever of other and unknown origin,” which saw an increase both during the day (incident rate ratio [IRR], 1.10; 95% CI, 1.05-1.17) and night (IRR, 1.23; 95% CI, 1.17-1.30).
Conclusion
The COVID-19 pandemic significantly influenced ED visit patterns, particularly by reducing non-emergent visits during nighttime.
8.Discordance Between Angiographic Assessment and Fractional Flow Reserve or Intravascular Ultrasound in Intermediate Coronary Lesions: A Post-hoc Analysis of the FLAVOUR Trial
Jung-Hee LEE ; Sung Gyun AHN ; Ho Sung JEON ; Jun-Won LEE ; Young Jin YOUN ; Jinlong ZHANG ; Xinyang HU ; Jian’an WANG ; Joo Myung LEE ; Joo-Yong HAHN ; Chang-Wook NAM ; Joon-Hyung DOH ; Bong-Ki LEE ; Weon KIM ; Jinyu HUANG ; Fan JIANG ; Hao ZHOU ; Peng CHEN ; Lijiang TANG ; Wenbing JIANG ; Xiaomin CHEN ; Wenming HE ; Myeong-Ho YOON ; Seung-Jea TAHK ; Ung KIM ; You-Jeong KI ; Eun-Seok SHIN ; Doyeon HWANG ; Jeehoon KANG ; Hyo-Soo KIM ; Bon-Kwon KOO
Korean Circulation Journal 2024;54(8):485-496
Background and Objectives:
Angiographic assessment of coronary stenosis severity using quantitative coronary angiography (QCA) is often inconsistent with that based on fractional flow reserve (FFR) or intravascular ultrasound (IVUS). We investigated the incidence of discrepancies between QCA and FFR or IVUS, and the outcomes of FFR- and IVUS-guided strategies in discordant coronary lesions.
Methods:
This study was a post-hoc analysis of the FLAVOUR study. We used a QCA-derived diameter stenosis (DS) of 60% or greater, the highest tertile, to classify coronary lesions as concordant or discordant with FFR or IVUS criteria for percutaneous coronary intervention (PCI). The patient-oriented composite outcome (POCO) was defined as a composite of death, myocardial infarction, or revascularization at 24 months.
Results:
The discordance rate between QCA and FFR or IVUS was 30.2% (n=551). The QCAFFR discordance rate was numerically lower than the QCA-IVUS discordance rate (28.2% vs. 32.4%, p=0.050). In 200 patients with ≥60% DS, PCI was deferred according to negative FFR (n=141) and negative IVUS (n=59) (15.3% vs. 6.5%, p<0.001). The POCO incidence was comparable between the FFR- and IVUS-guided deferral strategies (5.9% vs. 3.4%, p=0.479).Conversely, 351 patients with DS <60% underwent PCI according to positive FFR (n=118) and positive IVUS (n=233) (12.8% vs. 25.9%, p<0.001). FFR- and IVUS-guided PCI did not differ in the incidence of POCO (9.5% vs. 6.5%, p=0.294).
Conclusions
The proportion of QCA-FFR or IVUS discordance was approximately one third for intermediate coronary lesions. FFR- or IVUS-guided strategies for these lesions were comparable with respect to POCO at 24 months.
9.Discordance Between Angiographic Assessment and Fractional Flow Reserve or Intravascular Ultrasound in Intermediate Coronary Lesions: A Post-hoc Analysis of the FLAVOUR Trial
Jung-Hee LEE ; Sung Gyun AHN ; Ho Sung JEON ; Jun-Won LEE ; Young Jin YOUN ; Jinlong ZHANG ; Xinyang HU ; Jian’an WANG ; Joo Myung LEE ; Joo-Yong HAHN ; Chang-Wook NAM ; Joon-Hyung DOH ; Bong-Ki LEE ; Weon KIM ; Jinyu HUANG ; Fan JIANG ; Hao ZHOU ; Peng CHEN ; Lijiang TANG ; Wenbing JIANG ; Xiaomin CHEN ; Wenming HE ; Myeong-Ho YOON ; Seung-Jea TAHK ; Ung KIM ; You-Jeong KI ; Eun-Seok SHIN ; Doyeon HWANG ; Jeehoon KANG ; Hyo-Soo KIM ; Bon-Kwon KOO
Korean Circulation Journal 2024;54(8):485-496
Background and Objectives:
Angiographic assessment of coronary stenosis severity using quantitative coronary angiography (QCA) is often inconsistent with that based on fractional flow reserve (FFR) or intravascular ultrasound (IVUS). We investigated the incidence of discrepancies between QCA and FFR or IVUS, and the outcomes of FFR- and IVUS-guided strategies in discordant coronary lesions.
Methods:
This study was a post-hoc analysis of the FLAVOUR study. We used a QCA-derived diameter stenosis (DS) of 60% or greater, the highest tertile, to classify coronary lesions as concordant or discordant with FFR or IVUS criteria for percutaneous coronary intervention (PCI). The patient-oriented composite outcome (POCO) was defined as a composite of death, myocardial infarction, or revascularization at 24 months.
Results:
The discordance rate between QCA and FFR or IVUS was 30.2% (n=551). The QCAFFR discordance rate was numerically lower than the QCA-IVUS discordance rate (28.2% vs. 32.4%, p=0.050). In 200 patients with ≥60% DS, PCI was deferred according to negative FFR (n=141) and negative IVUS (n=59) (15.3% vs. 6.5%, p<0.001). The POCO incidence was comparable between the FFR- and IVUS-guided deferral strategies (5.9% vs. 3.4%, p=0.479).Conversely, 351 patients with DS <60% underwent PCI according to positive FFR (n=118) and positive IVUS (n=233) (12.8% vs. 25.9%, p<0.001). FFR- and IVUS-guided PCI did not differ in the incidence of POCO (9.5% vs. 6.5%, p=0.294).
Conclusions
The proportion of QCA-FFR or IVUS discordance was approximately one third for intermediate coronary lesions. FFR- or IVUS-guided strategies for these lesions were comparable with respect to POCO at 24 months.
10.Impact of COVID-19 pandemic on emergency department visits during daytime and nighttime
Ah Young KIM ; Young-Hoon YOON ; Jung-Youn KIM ; Bosun SHIM ; Sung Joon PARK
Journal of the Korean Society of Emergency Medicine 2024;35(6):413-423
Objective:
There has been a rapid increase in the utilization of emergency departments (EDs), especially for non-emergent cases. The challenges of accessing medical services at night cause disparities in ED utilization between the day and night. Additionally, the coronavirus disease-2019 (COVID-19) pandemic has had a notable impact on ED visits. This study aimed to compare the characteristics of patients visiting the EDs in the daytime and at night before and after COVID-19.
Methods:
A retrospective observational study was conducted on adults (≥18 years) at three metropolitan EDs from January 1, 2019 to December 31, 2020. Data, including the Korean Triage Acuity System, Tenth Revision (ICD-10) codes, and ICU admissions, were collected. Characteristics of patients visiting the ED during the day (06:00-18:00) and night (18:00-06:00) periods before and after COVID-19 were analyzed.
Results:
During the pre-COVID-19 and COVID-19 periods, 117,896 and 92,915 patients visited the ED, respectively. Non-emergency nighttime visits were increased than daytime visits during both the pre-COVID-19 period (37.9% vs. 30.9%) and the COVID-19 period (35.4% vs. 28.8%) (P<0.01). During COVID-19, non-emergency patient visits to the ED during the nighttime decreased compared to those during the day (odds ratio, 0.96; 95% confidence interval [CI], 0.93-0.99, P=0.01). Among the top five diagnoses, the number of patients declined during the COVID-19 pandemic in most categories, except for the category of “Fever of other and unknown origin,” which saw an increase both during the day (incident rate ratio [IRR], 1.10; 95% CI, 1.05-1.17) and night (IRR, 1.23; 95% CI, 1.17-1.30).
Conclusion
The COVID-19 pandemic significantly influenced ED visit patterns, particularly by reducing non-emergent visits during nighttime.

Result Analysis
Print
Save
E-mail