1.Safety and effectiveness of direct oral anticoagulants in fragile patients with venous thromboembolism:a retrospective cohort observational study
Hojong PARK ; Sang Jun PARK ; Hyangkyoung KIM
Annals of Surgical Treatment and Research 2025;108(3):168-176
Purpose:
The use of direct oral anticoagulants (DOACs) is challenging in fragile patients, including those with cancer, chronic kidney disease (CKD), and old age. We aimed to compare the safety of DOACs in terms of bleeding complications in these patients.
Methods:
Using hospital data from 2013 to 2019, we compared the risk of bleeding and major bleeding, including intracranial bleeding, any bleeding requiring transfusion, and all-cause bleeding, in patients with venous thromboembolism (VTE) who were naïve to DOAC (n = 12,369) and warfarin (n = 4,123). Hazard ratios (HRs) for the clinical outcomes were analyzed using Cox regression analysis, with warfarin as a reference.
Results:
The study included 4,078 eligible patients, predominantly female (54.1%), with a mean age of 62.5 years. DOACs were the primary treatment in 74.1% of the patients. DOAC treatment was associated with lower all-cause mortality compared to warfarin (HR, 0.799; 95% confidence interval [CI], 0.707–0.904). Although rates of recurrent VTE or major bleeding did not significantly differ between the groups, DOAC-treated patients had lower bleeding risk (HR, 0.562; 95% CI, 0.393–0.805; P = 0.002). The individual DOAC drugs did not differ significantly in terms of composite outcomes, recurrence, or bleeding events.
Conclusion
DOAC showed comparable outcomes with warfarin in the fragile patient population.
2.Safety and effectiveness of direct oral anticoagulants in fragile patients with venous thromboembolism:a retrospective cohort observational study
Hojong PARK ; Sang Jun PARK ; Hyangkyoung KIM
Annals of Surgical Treatment and Research 2025;108(3):168-176
Purpose:
The use of direct oral anticoagulants (DOACs) is challenging in fragile patients, including those with cancer, chronic kidney disease (CKD), and old age. We aimed to compare the safety of DOACs in terms of bleeding complications in these patients.
Methods:
Using hospital data from 2013 to 2019, we compared the risk of bleeding and major bleeding, including intracranial bleeding, any bleeding requiring transfusion, and all-cause bleeding, in patients with venous thromboembolism (VTE) who were naïve to DOAC (n = 12,369) and warfarin (n = 4,123). Hazard ratios (HRs) for the clinical outcomes were analyzed using Cox regression analysis, with warfarin as a reference.
Results:
The study included 4,078 eligible patients, predominantly female (54.1%), with a mean age of 62.5 years. DOACs were the primary treatment in 74.1% of the patients. DOAC treatment was associated with lower all-cause mortality compared to warfarin (HR, 0.799; 95% confidence interval [CI], 0.707–0.904). Although rates of recurrent VTE or major bleeding did not significantly differ between the groups, DOAC-treated patients had lower bleeding risk (HR, 0.562; 95% CI, 0.393–0.805; P = 0.002). The individual DOAC drugs did not differ significantly in terms of composite outcomes, recurrence, or bleeding events.
Conclusion
DOAC showed comparable outcomes with warfarin in the fragile patient population.
3.Safety and effectiveness of direct oral anticoagulants in fragile patients with venous thromboembolism:a retrospective cohort observational study
Hojong PARK ; Sang Jun PARK ; Hyangkyoung KIM
Annals of Surgical Treatment and Research 2025;108(3):168-176
Purpose:
The use of direct oral anticoagulants (DOACs) is challenging in fragile patients, including those with cancer, chronic kidney disease (CKD), and old age. We aimed to compare the safety of DOACs in terms of bleeding complications in these patients.
Methods:
Using hospital data from 2013 to 2019, we compared the risk of bleeding and major bleeding, including intracranial bleeding, any bleeding requiring transfusion, and all-cause bleeding, in patients with venous thromboembolism (VTE) who were naïve to DOAC (n = 12,369) and warfarin (n = 4,123). Hazard ratios (HRs) for the clinical outcomes were analyzed using Cox regression analysis, with warfarin as a reference.
Results:
The study included 4,078 eligible patients, predominantly female (54.1%), with a mean age of 62.5 years. DOACs were the primary treatment in 74.1% of the patients. DOAC treatment was associated with lower all-cause mortality compared to warfarin (HR, 0.799; 95% confidence interval [CI], 0.707–0.904). Although rates of recurrent VTE or major bleeding did not significantly differ between the groups, DOAC-treated patients had lower bleeding risk (HR, 0.562; 95% CI, 0.393–0.805; P = 0.002). The individual DOAC drugs did not differ significantly in terms of composite outcomes, recurrence, or bleeding events.
Conclusion
DOAC showed comparable outcomes with warfarin in the fragile patient population.
4.Update of Non-Thermal Non-Tumescent Technique for Varicose Vein Treatment
Annals of phlebology 2024;22(2):52-56
Non-thermal, non-tumescent (NTNT) techniques for varicose vein treatment have gained significant attention as alternatives to traditional thermal ablation methods, providing less invasive options with fewer complications and less downtime. This review examines the efficacy, safety, and patient outcomes associated with NTNT modalities such as cyanoacrylate adhesive closure, mechanochemical ablation (MOCA), and polidocanol endovenous microfoam (PEM). Recent trials suggest these NTNT methods achieve closure rates comparable to thermal methods, with lower complication rates and improved patient satisfaction. Key metrics from recent studies, including technical success, recurrence rates, and complication profiles, underscore the promise of NTNT techniques as first-line therapies. Findings also indicate variability in recurrence rates and complication profiles depending on vein anatomy and patient characteristics. In conclusion, NTNT approaches represent a promising evolution in varicose vein treatment, warranting further studies to standardize outcomes and optimize patient selection.
5.Direct Oral Anticoagulants in Fragile Patients with Venous Thromboembolism
Hojong PARK ; Sang Jun PARK ; Jeong-Ik PARK ; Jin Sung KIM ; Jin Ah KWON ; Hyangkyoung KIM
Annals of phlebology 2024;22(2):39-43
Venous thromboembolism (VTE), a severe condition comprising deep vein thrombosis and pulmonary embolism, requires prompt treatment. Traditional therapies include heparin, low-molecular-weight heparin, and warfarin. Direct oral anticoagulants (DOACs) such as dabigatran, rivaroxaban, apixaban, and edoxaban has revolutionized VTE management. Clinical trials show that DOACs are as effective as traditional anticoagulants in preventing recurrent VTE, with similar or lower rates of major bleeding. However, DOAC use is complex in vulnerable populations—those with comorbidities, chronic kidney disease, cancer, and advanced age—due to higher VTE and bleeding risks from polypharmacy and altered pharmacokinetics. Trials have shown promising results for DOACs, but these studies often include few patients from these high-risk groups. Moreover, while DOACs are validated for atrial fibrillation, these findings may not apply directly to patients with VTE due to different dosing. In this study, we aimed to address this gap by reviewing the literature on the efficacy and safety of DOACs in these vulnerable populations.
6.Validation of operational definitions of mortality in a nationwide hemodialysis population using the HealthInsurance Review and Assessment Service databases of Korea
Dong Hee LEE ; Ye-Jee KIM ; Hyangkyoung KIM ; Hyung Seok LEE
Kidney Research and Clinical Practice 2024;43(2):156-164
Health Insurance Review and Assessment Service’s (HIRA) claims data have been used in studies of hemodialysis patients even though information about mortality is not provided in this database. Mortality analysis using HIRA data has been conducted using various operational definitions that have not been validated. This study aimed to validate operational definitions of mortality for maintenance hemodialysis patients that have been used when analyzing the Korean HIRA database. Methods: This study utilized claims data of the Korean National Health Insurance Service (NHIS) between January 2008 and December 2019. We estimated mortality based on operational definitions applied in previous studies using the HIRA database and compared it with NHIS mortality information to validate accuracy. Results: A total of 128,876 patients who started maintenance hemodialysis between January 2009 and December 2019 were analyzed. The accuracy of estimated mortality was the highest at 96% in the group where mortality was defined as an absence of claims data for 150 days. If the period of no claims data was set to 90 days or less, there was a risk of overestimating the mortality for the entire study period. When it was set to 180 days or more, there was a risk of underestimating the mortality, as the follow-up time was close to the end of the study period. Conclusion: When mortality analysis of maintenance hemodialysis patients is performed using HIRA data, it is most accurate to set the operational definition period as the absence of claims data for 150 days.
7.Incidence and Risk Factors of Iliac Artery Rupture during Aortoiliac Stenting
KwangJin LEE ; Sungsin CHO ; Hyangkyoung KIM ; Jin Hyun JOH
Vascular Specialist International 2024;40(1):5-
Purpose:
Aortoiliac occlusive disease (AIOD) is widely prevalent and leads to severe claudication or chronic limb-threatening ischemia. Stent placement for AIOD demonstrated excellent outcomes in terms of long-term patency. However, iliac artery rupture is the most fearful complication during the aortoiliac stenting (AIS). This study aimed to evaluate the incidence and risk factors of iliac artery rupture during AIS.
Materials and Methods:
A retrospective review of consecutive patients with AIOD treated with AIS from 2009 to 2021 was completed. We excluded patients with instent restenosis. All types of stents, including self-expanding stent (SES), balloonexpandable stent (BES), or balloon-expandable covered stent (CS), were used.Angiographic characteristics and procedural outcomes were analyzed. Procedural success was defined as the residual stenosis <30%.
Results:
A total of 242 patients (86.8% male; mean age 68.8±10.0 years) with de novo AIOD were treated with AIS. The procedural success rate was 100%. Rupture occurred in six patients (2.5%) and all ruptures were occurred in the external iliac artery (EIA). Stenting of the EIA and less calcified lesion were risk factors for iliac rupture (P=0.028). All cases of iliac artery rupture were successfully treated with the CSs. Overall primary patency rates were 98.0% and 93.4% at 12 and 36 months, respectively. Primary patency rates of SES, BES, and CS were 87.7%, 88.4%, and 100% at 36 months, respectively.
Conclusion
The incidence of iliac artery rupture during AIS was 2.5%. Stent placement in the less calcified lesion and EIA was a risk factor for rupture during AIS. Placement of the CS can be the straightforward solution in case of iliac artery rupture during AIS.
8.Treatment of abdominal aortic aneurysms in Korea: a nationwide study
Hyangkyoung KIM ; Tae-Won KWON ; Yong-Pil CHO ; Jun Gyo GWON ; Youngjin HAN ; Sang Ah LEE ; Ye-Jee KIM ; Seonok KIM
Annals of Surgical Treatment and Research 2023;105(1):37-46
Purpose:
Although endovascular aneurysm repair (EVAR) has been shown to be superior to open surgical repair (OSR) for abdominal aortic aneurysm (AAA) treatment, no large-scale studies in the Korean population have compared outcomes and costs.
Methods:
The National Health Insurance Service database in Korea was screened to identify AAA patients treated with EVAR or OSR from 2008 to 2019. Perioperative, early postoperative, and long-term survival were compared, as were reinterventions and complications. Patients were followed-up through 2020.
Results:
Of the 13,631 patients identified, 2,935 underwent OSR and 10,696 underwent EVAR. Perioperative mortality rate was lower in the EVAR group (4.2% vs. 8.0%, P < 0.001) even after excluding patients with ruptured AAA (2.7% vs.3.3%, P = 0.003). However, long-term mortality rate per 100 person-years was significantly higher in the EVAR than in the OSR group (9.0 vs. 6.4, P < 0.001), and all-cause mortality was lower in the OSR group (hazard ratio, 0.9; 95% confidence interval, 0.87–0.97, P = 0.008). EVAR had a higher AAA-related reintervention rate per 100 person-years (1.75 vs. 0.52), and AAA-related reintervention costs were almost 10-fold higher with EVAR (US dollar [USD] 6,153,463) than with OSR (USD 624,216).
Conclusion
While EVAR may have short-term advantages, OSR may provide better long-term outcomes and costeffectiveness for AAA treatment in the Korean population, under the medical expense system in Korea.
9.Clinical outcome of graft removal versus preservation in abdominal aortic graft infection: a systematic review and meta-analysis
Hyangkyoung KIM ; Han Zo CHOI ; Yujin KWON ; Nicos LABROPOULOS
Annals of Surgical Treatment and Research 2023;105(4):207-218
Purpose:
The purpose of this study was to compare the clinical outcomes of abdominal aortic graft infection (AGI) treated with removal of the graft vs. graft preservation.
Methods:
The electronic databases PubMed, Embase, and Cochrane Library for studies that reported on AGI were searched. Observational studies and case series of at least 10 cases that reporting on the prevalence, microbiology, and outcomes of AGI were included.
Results:
Our search identified 23 studies that met our inclusion criteria, reporting on a total of 873 patients who underwent open surgical repair (OSR) or endovascular aneurysm repair (EVAR). Of these patients, 833 received graft removal, and 40 received graft preservation. The prevalence of AGI was reported to be 1.0% (95% confidence interval [CI], 0.5%–1.8%) after OSR and 0.4% (95% CI, 0%–1.1%) after EVAR. The pooled estimates of 1-year, 2-year, and 5-year mortality were 28.7% (95% CI, 19.4%–38.8%), 36.6% (95% CI, 24.6%–49.5%), and 51.8% (95% CI, 38.4%–65.1%) in the graft removal group and 16.1% (95% CI, 4.1%–32.2%), 18.5% (95% CI, 5.7%–35.1%), and 50.0% (95% CI, 31.6%–68.4%) in the graft preservation group.The 30-day mortality rate’s risk ratio (RR) for graft removal vs. preservation was 0.98 (95% CI, 0.40–2.38), while the 1-year mortality rate’s RR was 3.44 (95% CI, 1.60–7.42).
Conclusion
The 30-day mortality rate of AGI treatment was found to be high, whether using graft removal or preservation.In selected patients, implementing antibiotics with graft preservation as an initial management may be helpful in reducing the mortality rate.
10.National trend of the treatment for chronic venous diseases in Korea between 2010 and 2020
SooBum SHON ; Hyangkyoung KIM ; Hyeong Cheol KIM ; Sungsin CHO ; Seung Hwan LEE ; Jin Hyun JOH
Annals of Surgical Treatment and Research 2023;104(1):27-33
Purpose:
Limited data are available on the nationwide trend of treatments for chronic venous disease (CVD). The aim of the present study was to identify the nationwide trends of CVD treatments in Korea.
Methods:
A serial, cross-sectional study was conducted with the use of time trends to analyze patients with CVD between 2010 and 2020. The trends in the number of patients and procedures were analyzed including sclerotherapy, open surgery, and endovenous thermal ablation (ETA). Health Insurance Review and Assessment Service data were used to analyze the trends. For the statistical analysis, MedCalc Statistical software was used. P < 0.05 was considered statistically significant.
Results:
A total of 1,867,307 patients with CVD were managed in Korea between 2010 and 2020. The annual number of patients with CVD increased from 143,108 in 2010 to 219,319 in 2020 (risk ratio [RR], 1.53; P < 0.001). The percentage of patients with CVD who had venous ulcer gradually decreased from 3.1% in 2010 to 1.7% in 2020 (RR, 0.86; P < 0.001). The number of conventional surgeries including stripping and local resection of varicose veins decreased from 32,384 in 2010 to 21,792 in 2020 (RR, 0.67; P < 0.001). The number of ETAs performed increased, from 290 in 2011 to 12,126 procedures in 2020 (RR, 41.81; P < 0.001).
Conclusion
The total number of patients with CVD increased during the last 11 years. The number of conventional open surgery and sclerotherapy procedures decreased. On the contrary, the number of ETAs significantly increased in Korea.

Result Analysis
Print
Save
E-mail