Seung Huh

Rationale: As the end-stage kidney disease (ESKD) population requiring vascular access for hemodialysis continues to grow, the Kidney Disease Outcomes Quality Initiative guidelines emphasize vessel preservation to ensure viability for future access. Preoperative ultrasound is commonly performed prior to arteriovenous (AV) access creation when available. However, its major limitation is the restricted imaging range, which impedes visualization of the complete vascular network. This study highlights the importance of reconsidering fluoroscopic venography as a complementary tool to ultrasound for improving AV access planning. Patient concerns: A man in his late forties and a septuagenarian woman with ESKD underwent AV access creation surgery for ongoing hemodialysis. Diagnoses: The surgical plans could not be determined solely based on preoperative ultrasound findings. In Patient 1, AV access using an artificial graft with the brachial artery as the inflow and the brachial vein as the outflow in a forearm loop configuration was considered as the primary option. In Patient 2, the cephalic vein drainage was unclear with ultrasound due to the clavicle. Interventions: The operation was performed with a transverse incision just below the elbow. Before the anastomosis, we conducted intraoperative fluoroscopic venography through the surgically exposed median cubital vein using a small amount of diluted contrast media to assess the overall venous drainage system in the upper arm. Outcomes: The initial surgical plans based on ultrasound findings were modified through intraoperative fluoroscopic venography. In Patient 1, the distal anastomosis was redirected to the median cubital vein, thereby preserving the deep vein. In Patient 2, fluoroscopic venography enabled the successful creation of AV access using an autologous vein instead of a graft by directly visualizing the cephalic vein drainage. At early follow-up, both accesses achieved successful maturation; however, long-term outcomes could not be fully assessed, and no access-related complications were observed during the observation period. Lessons: Intraoperative fluoroscopic venography allowed for more precise AV access planning by providing real-time visualization of venous anatomy. This approach can facilitate intraoperative decision-making and help expand access options for ESKD patients while preserving future options.

Hyeonju Kim, Deokbi Hwang, Seung Huh, and Hyung-Kee Kim. Vasc Specialist Int 2025;41:. https://doi.org/10.5758/vsi.250034

This study evaluated the effect of pre-emptive embolization of the aortic side branches on the short-term incidence of type II endoleaks (T2ELs) and aneurysm sac changes following endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs). Data of 157 patients with degenerative large AAAs (≥50 mm for males and ≥45 mm for females) treated between January 2019 and October 2024 were retrospectively analyzed. The patients were categorized into the pre-emptive embolization (n=30, 19.1%) and non-embolization (n=127) groups. Embolization was considered for patients with high-risk factors for T2EL, specifically an inferior mesenteric artery (IMA) diameter ≥3 mm and a large lumbar artery diameter. Outcomes were assessed 1 month and 1 year postoperatively. The primary outcome was T2EL incidence, and the secondary outcomes were changes in aneurysm size and reintervention rates. At 1 month postoperatively, T2EL incidence was significantly lower in the embolization group (3.3%, 1/30) than in the non-embolization group (22.8%, 29/127) (P=0.015). At 1 year postoperatively, the T2EL incidence was 8.0% (2/25) in the embolization group and 23.0% (23/100) in the non-embolization group, although the difference was not statistically significant (P=0.094). Sac expansion was absent in the embolization group, whereas 4.0% of patients in the non-embolization group experienced expansion (P=0.583). Subgroup analysis for 37 patients with patent IMA ≥3 mm showed a significantly lower T2EL incidence at 1 month (5.6% vs. 52.6%, P=0.002) and 1 year (12.5% vs. 52.9%, P=0.014) postoperatively in the embolization group. Additionally, sac shrinkage was higher in the embolization group than in the non-embolization group (56.2% vs. 23.5%, P=0.055). Multivariable analysis confirmed pre-emptive embolization as an independent protective factor for T2EL at 1 year postoperatively (odds ratio 0.071, 95% confidence interval, 0.008-0.663; P=0.020). Pre-emptive embolization reduced the incidence of early T2EL after EVAR and showed stable outcomes at the 1-year follow-up, particularly in patients with large patent IMA diameters.

Background: Mycophenolate mofetil (MMF) is usually prescribed with a reduced fixed dose in Asian kidney transplant recipients (KTRs). However, the clinical efficacy and safety of the fixed dose have not yet been investigated via therapeutic drug monitoring. We evaluated whether reduced fixed-dose MMF is an optimal dosing strategy to achieve the therapeutic target of mycophenolic acid (MPA) exposure in Korean KTRs. Methods: This open-label, prospective study enrolled 50 de novo KTRs prescribed with tacrolimus, corticosteroid, and fixed-dose MMF (1.0–1.5 g/day). The trough level (C0) and area under the curve (AUC0–12 hr) of MPA were measured at 1 and 24 weeks after kidney transplantation (KT). The relationship of body weight (BW)-adjusted MMF dose with MPA C0 and MPA AUC0–12 hr was assessed using linear regression analysis. Results: The initial fixed dose of MMF of 1.44 ± 0.16 g/day was adjusted in 24 patients (48.0%) and then reduced to a mean dose of 1.19 ± 0.31 g/day at 24 weeks after KT. Most patients (≥84.0%) attained the minimum required MPA C0 of 1.0 μg/mL and MPA AUC0–12 hr of 30 μg × hr/mL at 1 and 24 weeks. The BW-adjusted MMF dose demonstrated significant positive correlations with MPA C0 and MPA AUC0– 12 hr at 1 and 24 weeks after KT. Moreover, 14 patients (28.0%) reported MPA-related adverse events that were predictable based on MPA AUC0–12 hr (cutoff level, 46.4 μg × hr/mL). Conclusion: The current reduced fixed-dose MMF strategy can help achieve the therapeutic target of MPA exposure in tacrolimus- treated Korean KTRs during the early posttransplant period.

Hyeon Ju Kim, Deokbi Hwang, Woo-Sung Yun, Seung Huh, and Hyung-Kee Kim. Vasc Specialist Int 2024;40:. https://doi.org/10.5758/vsi.240071

Young Ryul Park, Ji Hyun Jung, Deokbi Hwang, Woo-Sung Yun, Seung Huh, and Hyung-Kee Kim. Vasc Specialist Int 2024;40:. https://doi.org/10.5758/vsi.240015

Hyung-Kee Kim, Suehyun Park, Deokbi Hwang, Woo-Sung Yun, and Seung Huh. Vasc Specialist Int 2024;40:. https://doi.org/10.5758/vsi.230112

Background: Venous malformations (VMs) are distinguished from lymphatic malformations (LMs) when specific diagnostic skin lesions are present. In the deep type, this is difficult by clinico‐radiologic evaluation alone. We aimed to investigate the usefulness of lymphatic vessel endothelial cell (LEC) markers for the differential diagnosis of the deep VMs and LMs.Methods: A retrospective study was conducted based on the medical records of patients with VMs and LMs who underwent biopsy with both D2‐40 and PROX‐1 immunohistochemistry. We compared the initial clinico‐radiological diagnosis with the final pathological diagnosis and identified which ones showed a difference.Results: From 261 patients who had VMs and LMs, 111 remained after the exclusion of those who showed definite surface diagnostic features. After pathological diagnosis with the expressions of D2‐40 and PROX‐1, 38 of 111 (34.2%) patients' final diagnoses were changed. Among these 38 cases, diagnosis was not changed by D2‐40 positivity alone, but changed by PROX‐1 positivity alone (52.6%) or by both (47.4%). The diagnostic changes were more frequent in the deep category (43.7%) than in the superficial category.Conclusions: Identifying the expression of D2‐40, and especially PROX‐1, in the differential diagnosis of VMs and LMs may provide important treatment guidelines and understanding their natural course.

Hyeon Ju Kim, Seung Huh, and Hyung-Kee Kim. Vasc Specialist Int 2023;39:. https://doi.org/10.5758/vsi.230077

Hyeon Ju Kim, Deokbi Hwang, Hyung-Kee Kim, Seung Huh, and Woo-Sung Yun. Vasc Specialist Int 2023;39:. https://doi.org/10.5758/vsi.230032