A 20-Year Analysis of Ruptured Abdominal Aortic Aneurysm Outcomes and Associated Factors in Korea.

BACKGROUND: Unlike western countries, which have reported distinct decreases in incidence of ruptured abdominal aortic aneurysm (rAAA) over the last few decades, epidemiologic studies in Korea have not shown significant changes in incidence or mortality of rAAA. The purpose of this study was to analyze the changes in rAAA treatment outcomes and various associated risk factors over the past 2 decades. METHODS: A 20-year retrospective multicenter review for rAAA cases from the period of January 2000 to December 2020 was undertaken. Preoperative, intraoperative and postoperative clinical data were extracted for patients diagnosed with rAAA. For analysis, outcomes from the early era, defined as patients treated between January 1, 2000, and December 31, 2010, were compared with outcomes from the late era, defined as patients treated between January 1, 2011, and December 31, 2020. RESULTS: The total in-hospital mortality was 34.1% in the early era compared to 44.8% in the late era. Patients in the late era were older than those in the early era (75.2 ± 10.3 years vs. 70.3 ± 8.9 years; P = 0.009). Treatment with rAAA endovascular aneurysm repair increased from 2.3% in early to 13.8% in late era (P = 0.031). In the early era, more patients were operated by experienced surgeons than the late era (78.1% vs. 45.9%; P = 0.002). The emergency room to operating room time did not show improvement over the 20 years. CONCLUSIONS: The results indicate that mortality rate of rAAA in Korea has not changed over the last 2 decades. The study suggests the need for national preventive strategies, improved systemic coordination, and potential centralization of vascular services to enhance survival rates for rAAA.

Vitis Vinifera Seed Extract Versus Micronized Purified Flavonoid Fraction for Patients with Chronic Venous Disease: A Randomized Noninferiority Trial.

BACKGROUND: Venoactive drugs (VADs) based on Vitis vinifera extract are widely used in Korea. However, studies on the clinical effects and head-to-head comparisons with other groups of VADs are limited. This trial aimed to evaluate whether Vitis vinifera seed extract was noninferior to the micronized purified flavonoid fraction (MPFF) in relieving venous symptoms and improving quality of life in patients with chronic venous disease. METHODS: In this double-blind prospective randomized trial, patients from 13 hospitals, who were diagnosed with venous incompetence by duplex ultrasound and classified as clinical class 1, 2, or 3 in the Clinical, Etiological, Anatomical, and Pathophysiological classifications were enrolled. The primary outcome was the change in the Chronic Venous Disease Quality of Life Questionnaire (CIVIQ-20) score at 8 weeks from baseline. Secondary outcomes included changes in the Aberdeen Varicose Vein Questionnaire, visual analog scale, and Venous Clinical Severity Score at 4 and 8 weeks from baseline. Moreover, the change in leg circumferences was measured at 8 weeks and compared to baseline. RESULTS: In total, 303 patients were enrolled and randomly assigned to receive either Vitis vinifera seed extract (n = 154) or MPFF (n = 149). The CIVIQ-20 scores at 8 weeks were significantly reduced compared to those at baseline in both groups. No significant intergroup difference in the change of CIVIQ-20 at 8 weeks from baseline was observed (-8.31 ± 14.63 vs. -10.35 ± 14.38, P = 0.29, 95% confidence interval -1.65 to 5.72). The lower limit of the 95% confidence interval was within the predefined noninferiority margin of 6.9. Furthermore, the Aberdeen Varicose Vein Questionnaire, visual analog scale, and Venous Clinical Severity Score scores significantly decreased at 4 and 8 weeks after randomization compared with baseline in both groups. No significant differences were observed in the reduction of each score between groups. The calf circumference measured at 8 weeks was significantly reduced compared to that at baseline in patients receiving Vitis vinifera seed extract. CONCLUSIONS: Vitis vinifera seed extract was noninferior to MPFF in relieving venous symptoms and improving the quality of life in patients with chronic venous disease.

Metformin Use and Long-term Clinical Outcomes in Kidney Transplant Recipients.

RATIONALE & OBJECTIVE: Metformin has been recommended for some patients with advanced chronic kidney disease. However, the value of metformin in kidney transplant recipients (KTRs) with pretransplant diabetes mellitus (DM) or posttransplant DM is uncertain. We investigated the clinical effects of metformin in KTRs. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: A total of 1,995 KTRs with diabetes from 6 tertiary referral centers in the Republic of Korea. EXPOSURE: Metformin usage was defined as the use of metformin for>90 days after kidney transplantation; 1,193 KTRs were metformin users, and 802 KTRs did not use metformin. Changing usage of metformin among those exposed for >90 days was also characterized. OUTCOME: Primary outcomes were all-cause mortality and death-censored graft failure (DCGF). Secondary outcomes were biopsy-proven acute rejection (BPAR) and lactic acidosis events. ANALYTICAL APPROACH: Survival analyses were conducted using multivariable Cox regression and competing risk analyses using Fine and Gray models. Changes in metformin use over time were modeled using a time-varying covariate. Metformin usage, mean daily dose, and hemoglobin A1c (HbA1c) changes were considered in the landmark analysis to address time-varying confounding. RESULTS: Metformin use was associated with a lower risk of DCGF (adjusted hazard ratio [AHR], 0.47 [95% CI, 0.23-0.96], P=0.038); there was no significant association with all-cause mortality (AHR, 0.94 [95% CI, 0.32-2.76], P=0.915) or BPAR (AHR 0.98 [95% CI, 0.62-1.54], P=0.942). In the subgroup analysis, metformin usage was associated with a reduced risk of all-cause mortality and a lower risk of DCGF for both pretransplantation DM and posttransplant DM groups. Metformin usage was associated with a lower risk of BPAR in the posttransplant DM group, although it was less effective in the pretransplantation DM group. There was no confirmed case of metformin-associated lactic acidosis (MALA) in the present cohort. A higher dose of metformin was correlated with lower risks of DCGF and BPAR. LIMITATIONS: Data on newer antidiabetic drugs such as SGLT2 inhibitors are limited, and there is potential limited generalizability to other populations. CONCLUSIONS: Metformin usage may benefit KTRs, as evidenced by its association with a reduced risk of DCGF and the absence of MALA events. Randomized controlled trials are needed to validate these observational findings.

Kidney Transplantation From Deceased Donors With Bloodstream Infection: A Multicenter Retrospective Study.

BACKGROUND: The use of organs from donors with infection is limited because of the possibility of transmission. We aimed to investigate the transmission after deceased donor transplantation with bloodstream infection (BSI). METHODS: A retrospective study of patients undergoing kidney or pancreas transplantation at five tertiary centers in Korea from January 2009 and November 2019 was performed. We analyzed the outcomes after transplantation from deceased donors with BSI. RESULTS: Eighty-six recipients received transplantation from 69 donors with BSI. The most common isolated pathogens from donors were Gram-positive bacteria (72.0%), followed by Gram-negative bacteria (22.7%), and fungi (5.3%). Appropriate antimicrobial agents were used in 47.8% of donors before transplantation. Transmission occurred only in 1 of 83 recipients (1.2%) from bacteremic donors and 1 of 6 recipients (16.7%) from fungemic donors. One-year patient and graft survival was 97.5%and 96.3%, respectively. There was no significant difference in graft and patient survival between patients who received organs from infected donors and noninfected donors. CONCLUSION: Using organs from donors with bacteremia seems to be a safe option with low transmission risk. The overall prognosis of using organs from donors with BSI is favorable.

Effect of Inflow Arterial Calcification on Arteriovenous Fistula Maturation.

BACKGROUND: The aim of this study is to investigate the effect of preexisting calcification in the inflow artery on maturation and flow volume of an arteriovenous fistula (AVF). METHODS: Patients who underwent AVF creation for hemodialysis were prospectively recruited between March and November 2017. On preoperative duplex ultrasound, calcification in the arterial media within 5 cm of the planned anastomosis area was assessed. Clinical maturation was defined as the successful use of the fistula for ≥75% of the dialysis sessions during a month within 6 months after surgery. Radiological maturation was defined as a venous diameter of ≥0.4 cm and a flow volume of ≥500 mL/min. Flow volumes of the inflow artery and the cephalic vein were measured at 6 and 12 weeks after AVF creation. RESULTS: Eighteen patients with calcification and 29 patients without calcification were enrolled in this study. There was no significant difference in the clinical and radiological maturation between the groups. The flow volume of the inflow artery, measured at 6 weeks postoperatively, was significantly higher in the noncalcification group than in the calcification group (P = 0.042). The flow volume of the inflow artery in the noncalcification group was increased at 12 weeks postoperatively (P = 0.091). Flow volume of the vein was higher in the noncalcification group than in the calcification group, although it did not reach statistical significance. CONCLUSIONS: In conclusions, preexisting arterial calcification did not adversely affect the AVF maturation. However, arterial calcification correlated with the flow volume of the inflow artery of AVF.

The Use of Antithrombotics Is Not Beneficial for Conservative Management of Spontaneous Isolated Dissection of the Superior Mesenteric Artery: A Meta-analysis.

BACKGROUND: Conservative treatment is feasible in most patients with spontaneous isolated dissection of the superior mesenteric artery (SID-SMA). However, the role of antiplatelet agents and anticoagulants is not well defined in either symptomatic or asymptomatic SID-SMA. This study aimed to conduct a meta-analysis, including a single-arm study, comparing the resolution rate of conservative management with versus without antithrombotics for symptomatic and asymptomatic SID-SMA. METHODS: A systematic search of electronic databases, including PubMed, EMBASE, and Cochrane Library, on August 22nd, 2018, was performed to identify studies concerning SID-SMA. Meta-analyses were conducted to determine the primary resolution rate, long-term aneurysmal change for symptomatic SID-SMA, and any event for asymptomatic SID-SMA. We calculated pooled risk ratios and 95% confidence intervals (CIs) using random-effects model in studies with two arms and in studies with two arms or a single arm. RESULTS: We included data from 35 articles involving 727 patients with SID-SMA (symptomatic 693, asymptomatic 134). No significant differences were observed in the successful resolution rate between conservative management with and without antithrombotics (random-effects model, risk ratio [RR] 0.96; 95% CI, 0.87-1.05]). The pooled resolution rate from combining single-arm studies was 91% (95% CI, 85-95) and 95% (95% CI, 88-100) in conservative management with and without antithrombotic, respectively, which was not statistically significant (RR, 0.97; 95% CI, 0.91-1.02). The pooled morphologic progression rate from combining single-arm studies was 3% (95% CI, 0-8) and 11% (95% CI, 2-26) in conservative management with and without antithrombotics, respectively, which was not statistically significant (RR, 0.44; 95% CI, 0.12-1.64). The adverse event was 0% for both groups for asymptomatic SID-SMA. CONCLUSIONS: Additional antithrombotic therapy for both symptomatic and asymptomatic SID-SMA did not benefit the outcomes. We do not recommend the use of antithrombotics for SID-SMA, unless further evidence shows any beneficial effect.

Successful Endovascular Treatment of a Ruptured Popliteal Artery Aneurysm in a Patient with Behcet Disease.

PURPOSE: Arterial involvement of Behcet disease is often found in the form of a rapidly expanding aneurysm. We report a case of successful treatment of a ruptured popliteal artery aneurysm with a stent-graft insertion. CASE REPORT: A 55-year-old male patient was admitted because of pain and swelling in the right leg that had persisted for 15 days. Computed tomography (CT) angiography showed a contained rupture of a large right popliteal artery aneurysm. Laboratory tests showed elevated erythrocyte sedimentation rate (ESR) and C-reactive protein level. The patient had a history of recurrent oral and genital ulceration, folliculitis, and erythema nodosum. He was diagnosed as having Behcet disease with arterial involvement. After 5 days of immunosuppressant medications, the ESR decreased. A 7 mm × 10 cm stent graft was inserted into the right popliteal artery, and completion angiography showed the successfully excluded aneurysm. His symptoms were gradually relieved. The stent graft was patent on CT angiography 15 months after the procedure. He has been followed up for 16 months with dual antiplatelet agents and immunosuppressive medications. CONCLUSIONS: Endovascular therapy for peripheral aneurysms in patients with Behcet disease is safe and minimally invasive. Careful follow-up to monitor disease progression is necessary.

Role of Laser Doppler for the Evaluation of Pedal Microcirculatory Function in Diabetic Neuropathy Patients.

OBJECTIVE: We evaluated whether LD can detect alterations in skin microcirculatory flow in type II diabetic neuropathy patients and determined which parameters were most predictive. METHODS: A prospective analysis was performed for three groups with presumed varying degrees of microvascular dysfunction: diabetics with neuropathy (DMN, n = 20), diabetics without microangiopathic complications (DM, n = 20), and healthy controls (n = 16). LD was performed under strictly controlled protocols with provocation, consisting of vasoconstrictive (valsalva, postural) and vasodilative tests (PORH, LTH). RESULTS: There was an overall decrease in LD values in response to both vasoconstrictive and vasodilative provocations in DMN patients compared to DM and control groups. Statistically significant parameters were as follows: valsalva, PORH and LTH between DMN and control; valsalva only between DMN and DM; and PORH and LTH between DM and control. ROC curve analysis showed that Valsalva was the most accurate parameter in DMN patients. CONCLUSIONS: LD could consistently detect differences in microcirculatory flow between the three study groups consisting of gradually more severe microvascular dysfunction. The Valsalva parameter was the most accurate in detecting established microvascular dysfunction, whereas PORH and LTH may have a possible role for detection of early microvascular impairment.

Changes in Saphenous Vein Stump and Low Incidence of Endovenous Heat-Induced Thrombosis After Radiofrequency Ablation of Great Saphenous Vein Incompetence.

BACKGROUND: Relationship between the distance of the catheter tip from the saphenous femoral junction and the length of residual stump after radiofrequency ablation (RFA) has not been sufficiently examined. OBJECTIVE: The purpose of this study was to investigate the change of great saphenous vein (GSV) stump with clinical outcomes after RFA. MATERIAL AND METHODS: From January 2014 to September 2014, 67 patients (91 limbs) underwent GSV RFA and the collected data were analyzed prospectively. Change of GSV stump length and clinical symptoms was evaluated at 1-, 3-, and 6-month intervals. Ablations were performed between 2 to 2.5 cm distal to the saphenofemoral junction. RESULTS: The residual GSV stump decreased in length to 1.465 ± 0.504 cm at the first month follow-up. This length persisted throughout the 1-, 3-, and 6-month follow-ups. There were no statistically significant differences during the follow-up period. Both the Venous Clinical Severity Score and the Aberdeen Varicose Vein Symptom Severity Score was significantly improved at 1 month and improved even further at 3 months. One patient (1.1%) developed endovenous heat-induced thrombosis (EHIT) Class 3 at 1-month follow-up and was treated with anticoagulation. CONCLUSION: This study has shown that the adequate positioning of RFA catheter tip (2.0-2.5 cm) is recommended to decrease the incidence of EHIT.

Time-varying maximal proteinuria correlates with adverse cardiovascular events and graft failure in kidney transplant recipients.

AIM: In the general population, proteinuria is associated with progression to kidney failure, cardiovascular disease, and mortality. Here, we analyzed the effects of proteinuria on outcomes in kidney transplant recipients. METHODS: We performed a retrospective, multi-centre cohort study involving 2047 recipients to evaluate the effects of post-transplant proteinuria on adverse cardiovascular events, graft failure, and mortality. Patients were classified into two groups according to their levels of proteinuria: patients without proteinuria (<150 mg/day, n = 1113) and proteinuric patients (≥ 150 mg/day, n = 934). Multivariate Cox hazard model was conducted with using the maximal proteinuria as time-varying covariate. RESULTS: During a median 55.3-month (range, 0.6-167.1) follow-up, there were 50 cases of major adverse cardiac events (cardiac death, nonfatal myocardial infarction, or coronary revascularization), 115 cases of graft failure, and 52 patient deaths. In multivariate Cox regression with time-varying covariate, proteinuric recipients were significantly associated with major adverse cardiac events (hazard ratio [HR] 8.689, 95% confidence interval [CI] 2.929-25.774, P < 0.001) compared to those without proteinuria. Recipients with proteinuria showed significantly higher incidences of acute rejection (23.1% vs. 9.4%, P < 0.001) and graft failure rate (HR 6.910, 95% CI 3.270-14.601, P < 0.001). In addition, mortality rate was also significantly higher in patients with proteinuria (HR 6.815, 95% CI 2.164-21.467, P = 0.001). CONCLUSION: Post-transplant proteinuria correlates with adverse cardiovascular events, graft failure, and mortality. Therefore, proteinuria should be evaluated and managed to improve the outcomes of renal recipients.

Pretransplant malnutrition, inflammation, and atherosclerosis affect cardiovascular outcomes after kidney transplantation.

BACKGROUND: Malnutrition, inflammation, and atherosclerosis (MIA) syndrome is associated with a high mortality rate in patients with end-stage renal disease. However, the clinical relevance of MIA syndrome in kidney transplantation (KT) recipients remains unknown. METHODS: We enrolled 1348 adult KT recipients. Recipients were assessed based on serum albumin, cholesterol, or body mass index for the malnutrition factor and C-reactive protein level for the inflammation factor. Any history of cardiovascular (CV), cerebrovascular, or peripheral vascular disease satisfied the atherosclerosis factor. Each MIA factors were assessed by univariate analysis and we calculated an overall risk score by summing up scores for each independent variable. The enrolled patients were divided into 4 groups depending on the MIA score (0, 2-4, 6, 8-10). RESULTS: The patients with higher MIA score showed worse outcome of fatal/non-fatal acute coronary syndrome (ACS) (p < 0.001) and composite outcomes of ACS and all-cause mortality (p < 0.001) than with the lower MIA score. In multivariate analysis, ACS showed significantly higher incidence in the MIA score 8-10 group than in the MIA score 0 group (Hazard ratio 6.12 95 % Confidence interval 1.84-20.32 p = 0.003). CONCLUSIONS: The presence of MIA factors before KT is an independent predictor of post-transplant CV outcomes.

Initial experience of thrombectomy using vascular snare with multiple loops for chronic organized thrombi in patients with thrombosed native hemodialysis fistulas.

BACKGROUND: Thrombi in native hemodialysis access frequently exhibit chronic organized feature because they have formed over a long period. Removal of these is quite difficult owing to relatively large volume, resilient feature, limitations of the introducer sheath size, etc. In this study, we report our experience using a vascular snare for the removal of these thrombi in native arteriovenous fistula (AVF). MATERIALS AND METHODS: The medical records of patients who underwent recanalization for thrombosed AVFs from January 2019 to August 2023 were reviewed. During the study period, a total of 29 native fistulas (19 brachiocephalic, nine radiocephalic, and one radiobasilic) in 25 patients were treated using a vascular snare with multiple loops (19 men and six women). Characteristics of the AVFs, endovascular procedures, technical and clinical results, and complications were evaluated. RESULTS: Anatomic and clinical success rates were 96.6% and 100%, respectively. Total thrombosis was observed in 21 (72.4%) fistulas. Aneurysmal changes were found in 22 (75.9%) fistulas. The mean fistula age at the time of the procedure was 60.9 months (standard deviation, 52.2). Thrombectomy was initiated using a vascular snare in 14 fistulas. In 15 fistulas for which the procedures were initiated using a rotational percutaneous thrombectomy device (PTD), a vascular snare was subsequently used because recanalization failed or was insufficient due to chronic organizing thrombi. Additional aspiration and balloon angioplasty were performed in 27 (93.1%) and 28 (96.6%), respectively. Pharmacological thrombolysis was performed in one fistula for long segmental thrombosis combined with arterial thrombosis. The mean procedure time, excluding thrombolysis, was 91.9 min (standard deviation, 55.5). No complications related to the use of the vascular snare was observed. CONCLUSION: The use of a vascular snare with multiple loops was safe and highly effective for the removal of chronic organized thrombi in the recanalization of thrombosed AVFs.

Outcomes of kidney allograft in recipients with kidney disease of unknown etiology.

The etiology of renal disease is important because the primary renal pathology may affect the outcomes of kidney allograft with respect to recurrence, rejection, and survival. However, for a significant number of patients who undergo kidney transplantation, the disease etiology is unknown. Here, allograft outcomes for patients with kidney disease of unknown etiology (UEK) at three affiliated Korean hospitals were identified. The incidence of biopsy-proven acute rejection (BPAR) for UEK was 22.9%, which was similar to the rates for diabetic nephropathy (DN, 24.4%) and IgA nephropathy (IgAN, 20.0%; p = 0.345). The cumulative incidence of post-transplant glomerulonephritis (PTGN) among patients with UEK was significantly lower than that among patients with IgAN (p < 0.001). Overall graft survival of the UEK group was superior to that of the DN group (hazards ratio 0.39, 95% confidence interval 0.17-0.92, p = 0.030). Preemptive transplantation for UEK significantly reduced the incidence of BPAR (preemptive vs. non-preemptive 9.6% vs. 30.3%, p = 0.001), but graft survival and recurrence were not affected by preemptive transplantation. The outcomes of kidney transplantation for patients with UEK were not inferior to those for patients with IgAN or DN. Preemptive kidney transplantation may be encouraged for UEK patients.

Infection of the Aortic Stent Graft to Treat Arterioureteral Fistula.

Arterioureteral fistula is a rare but life-threatening condition. An endovascular treatment approach is commonly used; however, there is a potential risk of infection. We present a case in which a patient presented with abdominal pain and was diagnosed with a ruptured internal iliac artery aneurysm and a subsequent arterioureteral fistula. An aortic stent graft was inserted to treat the arterioureteral fistula, but it subsequently became infected, resulting in the patient's death. This case underscores the importance of early diagnosis and treatment of arterioureteral fistula and the possibility of graft infection.

Treatments for symptomatic class I patients in CEAP classification with saphenous vein reflux: A pilot study.

BACKGROUND: For patients with telangiectasia or reticular veins (CEAP [clinical, etiologic, anatomic, pathophysiologic] class C1), less invasive endovenous (EV) treatments have emerged. However, no prospective studies have compared compression stockings (CSs) and EV ablation treatment for C1 symptomatic refluxing saphenous veins. The present prospective study compared the therapeutic results of the two treatment modalities. METHODS: From June 2020 to December 2021, 46 patients with telangiectasia or reticular veins (<3 mm; class C1) with axial saphenous reflux and venous congestion symptoms were prospectively enrolled. The patients were assigned to CS (n = 21) or EV treatment (n = 25), according to patient preference. Complications, clinical improvement scales (eg, the venous clinical severity score [VCSS]), and quality of life, including the Aberdeen varicose vein symptom severity score (AVSS) and venous insufficiency epidemiological and economic study - quality of life/symptoms (VEINES-QOL/Sym), were evaluated and compared between the two groups at 1, 3, and 6 months after treatment. RESULTS: No major complications occurred in either group. The median VCSS was 2.0 (interquartile range [IQR], 1.0-2.0), 1.0 (IQR, 0.5-2.0), 1.0 (IQR 0.0-1.0), and 0.0 (IQR 0.0-1.0) at baseline and 1, 3, and 6 months after treatment in the CS group, respectively. The corresponding VCSSs were 3.0 (IQR, 1.0-3.0), 1.0 (IQR, 0.0-1.0), 0.0 (IQR, 0.0-0.0), and 0.0 (IQR, 0.0-0.0) in the EV group. The median AVSS was 4.4 (IQR, 3.0-5.5), 2.1 (IQR, 1.3-4.6), 1.0 (IQR, 0.0-2.8), and 0.0 (IQR, 0.0-1.8) at baseline and 1, 3, and 6 months after treatment in the CS group, respectively. The corresponding scores were 6.2 (IQR, 3.8-12.3), 1.6 (IQR, 0.6-2.8), 0.0 (IQR, 0.0-2.6), and 0.0 (IQR, 0.0-0.4) in the EV group. The mean VEINES-QOL/Sym score was 92.7 ± 8.1, 100.4 ± 7.3, 104.3 ± 8.2, and 106.0 ± 9.7 in the CS group at baseline and 1, 3, and 6 months after treatment, respectively. The corresponding scores were 83.6 ± 8.0, 102.9 ± 6.6, 107.9 ± 3.9, and 109.6 ± 3.7 in the EV group. Both groups showed considerable improvement in the VCSS, AVSS, and VEIN-SYM/QOL scores, and no significant between-group differences were observed for ≤6 months. Among the severely symptomatic patients (pretreatment VEINES-QOL/Sym score ≤90), the EV group exhibited more marked improvement (P = .029 for the VCSS and P = .030 for the VEINES-QOL/Sym score). CONCLUSIONS: Both CSs and EV treatment provided clinical and quality of life improvement in symptomatic C1 patients with refluxing saphenous veins, with no significant between-group differences. However, a subgroup analysis revealed that EV treatment provided statistically significant improvement in the severe symptomatic C1 group.

Outcome after early thrombotic occlusion of arteriovenous fistulas.

OBJECTIVE: Arteriovenous fistulas (AVFs) are considered the first choice for venous access in end-stage renal disease patients, however, they are also known to have a high primary failure rate (early thrombosis and maturation failure). Of these, the outcome of thrombosed immature AVFs is not well known. This study aimed to investigate the outcome of AVFs with early thrombosis. METHODS: Patients who underwent AVF creation from January 2009 to December 2019 at Seoul National University Hospital or Seoul Metropolitan Government - Seoul National University Boramae Medical Center were retrospectively reviewed. Patients who received salvage operations due to early thrombosis within 30 days after access creation were analyzed. RESULTS: During the study period, a total of 45 patients (radiocephalic 26; brachiocephalic 19) developed early thrombosis and underwent salvage operations. The median age of patients was 61.0 (54.5-69.5) years, and 51.1% were male. The first salvage operation was performed on the median 1.0 (0.0-4.5) day after AVF creation. The most common cause for early thrombosis was venous stenosis (64.4%) and followed by poor arterial inflow (28.9%), especially in radiocephalic AVFs. About 20 AVFs were salvaged to maturation (46.5%). Post-salvage primary patency and secondary patency at 1 year was 72.6% and 100%. In a multivariate logistic regression, significant risk factors for maturation failures were minimum venous outflow diameter ⩽2.5 mm (OR, 4.433; 95% CI, 1.039-18.921; p = 0.044) and lower in patients with hypertension (OR, 0.064; 95% CI, 0.006-0.637; p = 0.019). CONCLUSIONS: Thrombosed immature AVFs are associated with a high failure rate after salvage operation. However, if the salvage operation is successfully performed, it is associated with an acceptable 1-year outcome.

Validation of I71.3 code for ruptured abdominal aortic aneurysm in Korea: misplaced diagnosis in claims data.

Purpose: Studies in western countries have shown a decline in the incidence of ruptured abdominal aortic aneurysm (rAAA) with advancements in endovascular repair and screening. However, according to health insurance data in Korea based on rAAA code (I71.3), overall rAAA has been increasing. This study aimed to validate the I71.3 code for rAAA and attempt to define the true incidence of rAAA in Korea. Methods: A 20-year multicenter retrospective review of rAAA was undertaken from the period of January 1, 2000 to December 31, 2020. All patients were diagnosed with the rAAA code I71.3 in each of the 4 hospitals. The CT images and surgical records of these patients were reviewed to differentiate true rAAA and misdiagnosis. Further data on true rAAA patient outcomes including mortality and treatment success were also collected. Results: A total of 305 rAAA (I71.3) codes were identified in the 4 centers. However, medical record review showed true rAAA in only 131 (43.0%). The remaining 174 cases (57.0%) were misdiagnosed. Impending ruptures were the most common misdiagnoses (37.9%). The total in-hospital mortality including deaths before treatment was 38.9% (n = 51), while mortality of treated patients was 24.4% (n = 15). Conclusion: The analysis of I71.3 code for rAAA showed that only 43.0% were true rAAA and the remaining 57.0% were misdiagnosed. This indicates that the I71.3 code is overestimated in National Health Insurance-based data and that the true incidence of rAAA could be much lower.

A multicenter, randomized, open-labelled, non-inferiority trial of sustained-release sarpogrelate versus clopidogrel after femoropopliteal artery intervention.

Optimal antiplatelet therapy after endovascular therapy (EVT) for peripheral artery disease is controversial. This trial aimed to evaluate whether sarpogrelate plus aspirin was non-inferior for preventing early restenosis after femoropopliteal (FP) EVT compared to clopidogrel plus aspirin. In this open-label, prospective randomized trial, 272 patients were enrolled after successful EVT for FP lesions. Patients in each group received aspirin 100 mg and clopidogrel 75 mg or sarpogrelate 300 mg orally once per day for 6 months. The primary outcome was target lesion restenosis at 6 months, tested for noninferiority. Patient characteristics and EVT patterns were similar, except for increased inflow procedures in the sarpogrelate group and increased outflow procedures in the clopidogrel group. The sarpogrelate group showed a tendency of less restenosis at 6 months than the clopidogrel group (13.0% vs. 19.1%, difference 6.1 percentage points, 95% CI for noninferiority - 0.047 to 0.169). Secondary endpoints related to safety outcomes were rare in both groups. Risks of target lesion restenosis of the two intervention arm were uniform across most major subgroups except for those with coronary artery disease. In conclusion, Sarpogrelate plus aspirin is non-inferior to clopidogrel plus aspirin in preventing early restenosis after FP EVT. Larger multi-ethnic trials are required to generalize these findings. Trial registration: National Institutes of Health Clinical Trials Registry (ClinicalTrials.gov identifier: NCT02959606; 09/11/2016).

Comparison of costs of endovascular repair versus open surgical repair for abdominal aortic aneurysm in Korea.

This study was designed to compare the hospital-related costs of elective abdominal aortic aneurysm (AAA) treatment and cost structure between endovascular aneurysm repair (EVAR) and open surgical repair (OSR) in Korean health care system. One hundred five primary elective AAA repairs (79 OSRs and 26 EVARs) performed in the Seoul National University Hospital from 2005 to 2009 were included. Patient characteristics were similar between two groups except for older age (P = 0.004) and more frequent history of malignancy (P = 0.031) in EVAR group. Thirty-day mortality rate was similar between two groups and there was no AAA-related mortality in both groups for 5 yr after repair. The total in-hospital costs for the index admission were significantly higher in EVAR patients (mean, KRW19,857,119) than OSR patients (mean KRW12,395,507) (P < 0.001). The reimbursement was also significantly higher in EVAR patients than OSR patients (mean, KRW14,071,081 vs KRW6,238,895, P < 0.001) while patients payments was comparable between two groups. EVAR patients showed higher follow-up cost up to 2 yr due to more frequent imaging studies and reinterventions for type II endoleaks (15.4%). In the perspective of cost-effectiveness, this study suggests that the determination of which method to be used in AAA treatment be more finely trimmed and be individualized.

Prognostic Value of Pre- and Post-Serum Alkaline Phosphatase Among Renal Transplant Recipients.

BACKGROUND: Recent studies have shown that high levels of serum alkaline phosphatase (ALP) are associated with all-cause and cardiovascular death among patients undergoing hemodialysis. However, there is limited knowledge on the effect of ALP level in kidney transplant recipients (KTRs). The aim of this study was to evaluate if serum ALP levels before and after transplant and the changes in ALP levels are associated with graft failure and mortality. METHODS: Between January 1997 and December 2012, 3029 KTRs were enrolled in a multicenter cohort. We examined the association of pre- and posttransplant serum ALP levels and long-term outcomes in KTRs. RESULTS: Pretransplant serum ALP level >80 IU/L was associated with a hazard ratio (HR) for graft failure of 1.571 in a fully adjusted model. The graft failure rate gradually increased with ALP level increments of 20 IU/L in KTRs with ALP levels >60 IU/L. An increase in serum ALP level by 40 IU/L during the first 3 months after kidney transplant was associated with higher rates of graft failure (HR, 2.353) and higher rates of mortality (HR, 2.733). CONCLUSIONS: Elevated pre-and posttransplant serum ALP levels and increases in the serum ALP levels after kidney transplant increase the risk of graft failure and mortality among KTRs.