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.

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.

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.

Patency of arteriovenous fistulas and grafts for dialysis access: An analysis using the Korean National Health Insurance Service database from 2008 to 2019.

BACKGROUND: Arteriovenous (AV) access practice and its outcomes vary internationally. To provide a better understanding of the patterns and outcomes of AV access creation, we investigated the patency and risk factors of arteriovenous fistulas (AVFs) and grafts (AVGs) as initial AV access in the Korean adult population using data from the last 10 years. METHODS: The National Health Insurance Service database was queried retrospectively to identify patients undergoing hemodialysis with AVFs and AVGs as well as their clinical characteristics and outcomes from 2008 to 2019. AV access patency and its associated risk factors were evaluated. RESULTS: During the study period, 64,179 AVFs and 21,857 AVGs were placed. The mean patient age was 62.6 ± 13.6 years (21.5% were ⩾75 years old), and 39.3% patients were women. More than half of the patients underwent AV access creation at tertiary care hospitals. At 1 year, the primary, primary assisted, and secondary patency rates were 62.2%, 80.7%, and 94.2% for AVFs, and 46.0%, 68.4%, and 86.8% for AVGs, respectively. AVG, older age, female sex, diabetes, and creation at general hospitals (vs tertiary hospitals) were associated with decreased patency outcomes (all, p < 0.05). CONCLUSION: This study using national data showed that three quarters of patients with AV access had AVF and AVF showed superior performance to AVG and identified several patient and center factors related to AV access patency in Korea.

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.

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.

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.

Outcomes of vein reconstruction using bovine pericardial patch.

BACKGROUND: The bovine pericardium is a good alternative material to the autogenous vein in vascular reconstruction. This study aimed to evaluate the results of angioplasty in venous reconstruction using bovine pericardium and identify the risk factors for significant complications. MATERIAL AND METHODS: A retrospective review was performed of the demographic data, clinical characteristics, and complications of patients who underwent vessel repair using bovine pericardium between February 2012 and December 2020. Univariate analysis was used to compare complication frequencies within several categories. RESULTS: There were 36 cases of patch angioplasty using bovine pericardium. The median age was 65 years; 61% of them were men. Of the 36 venous repairs, 31 (86.1%) were from cancer surgery and five (13.9%) were from iatrogenic injury. Patch shape was used in 27 cases (75.0%), while tube shape was used in nine cases (25.0%). The incidence of occlusion and partial thrombus was five (13.9%) and three (8.3%) cases, respectively. Of the nine tube-shaped angioplasties, four (44.4%) required reoperation due to early thrombosis (three cases) and hematoma (one case). CONCLUSION: The use of a bovine pericardial patch in the reconstruction of a damaged vein from tumor invasion or iatrogenic injury is feasible. However, the complication rate of vessel patency remains substantial, especially in cases of iatrogenic injury or when a tube-shaped form is used for repair.

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.

Outcome after kidney transplantation in hepatitis B surface antigen-positive patients.

Few reports detail the actual outcome of Hepatitis B Surface Antigen-positive patients after kidney transplant. HBsAg-positive patients who underwent kidney transplant between January, 1999, and December, 2018, were reviewed retrospectively. Outcomes including hepatitis B reactivation rate, risk factors for reactivation, and patient and graft survival rates were analyzed. Seventy-seven patients were enrolled (47.1 ± 11.5 years old). Patients received ABO-incompatible (n = 5), crossmatch positive transplant (n = 2), and re-transplant (n = 4). Forty-six patients received prophylactic; 19, medication at least 3 months before the transplant; and 12, did not receive medication. Seventeen out of 76 patients developed reactivation post-transplant. 52.9% of HBV reactivation was accompanied by hepatitis. Inappropriate, other than lifelong prophylactic, antiviral agents (HR = 7.34, 95% CI 1.51-35.69, P = 0.01) and high hepatitis DNA (≥ 1000 IU/ml) pre-transplant (HR = 4.39, 95% CI 1.08-17.81, P = 0.04) increased reactivation risk. There was no significant difference in patient and graft survival between antigen positive patients who received antiviral agent and propensity score matched negative patients. HBsAg positivity in kidney transplant recipients is associated with substantial HBV reactivation rate. Lifelong antiviral therapy is mandatory, and patients with high preop HBV titer should be monitored closely for HBV reactivation.

Single versus en bloc kidney transplant from donors less than or equal to 15 kg to pediatric recipients.

With small kidneys, EBKTs could provide sufficient renal mass but could lead to inefficient use of resources, while SKTs could result in insufficient function due to small renal mass. We aimed to compare the outcomes of EBKT and SKT from small donors weighing ≤15 kg to pediatric recipients. We retrospectively reviewed all pediatric patients who met the inclusion criteria between January 1, 1984, and April 30, 2019, at a single institution. Of a total of 23 patients, 12 received EBKT and 11 received SKT. The median age of donors, weight of donors, and weight of recipients were comparable between the two groups. The median age of recipients and median weight of allografts were greater in the EBKT group than in the SKT group. The median follow-up was 53.9 months. There was no significant difference in eGFR, protein creatinine ratios at 1-year follow-up, and overall graft survival. The size of the kidney increased by approximately 13%-43% in the EBKT group and 40%-60% in the SKT group. This study demonstrated that kidneys from small donors weighing 5-15 kg could be split in pediatric recipients without compromising the outcome.

Crucial Roles of Vascular Surgeons in Oncovascular and Non-Vascular Surgery.

OBJECTIVE: Vascular surgeons can be useful in non-vascular surgery cases, especially in oncology where complete resection is important. Such activity has been quantified at least locally, but maybe not adequately reported in a systematic manner, or studied prospectively. This study aimed to describe the roles of vascular surgeons in oncovascular surgery (OVS) and non-vascular surgery (NVS), and to analyse the yearly trends of consult surgery, early mortality and morbidity and risk factors for poor outcomes. METHODS: This study was a five year retrospective review of the role of vascular surgeons in various settings at a tertiary hospital. Electronic medical records and images were reviewed retrospectively. Between January 2014 and December 2018, the vascular surgery registry data of Seoul National University Hospital were reviewed for OVS or NVS assisted by vascular surgeons and operations primarily done by vascular surgeons. Demographic data, clinical characteristics, operative data, vascular related data and operative outcomes were collected. The operations were classified into primary surgery or consult surgery. Consult procedures were divided into planned or unplanned surgery. RESULTS: Of 564 cases, vascular surgeons performed 74 OVS as primary surgery, and retroperitoneal tumour was the most frequent diagnosis (n = 34). There were 490 intra-operative requests for a vascular surgeon's assistance, of which 109 were emergency calls. Total intra-operative consultations increased by 115.9% over five years, and the proportion of unplanned operations also increased. Unplanned assistance was most commonly requested for bleeding, whereas node dissection was the most common reason for planned surgery. The mortality rate was not different between the planned and unplanned surgery groups, but the latter showed worse outcomes in total operating time, length of hospital stay, post-operative consultations, and post-operative vascular related complications. CONCLUSION: Vascular surgeons have an essential role to play in the modern practice of cancer surgery. Oncovascular surgery enables gross resection of a tumour even in the presence of major vessel invasion. Emergency unplanned surgery had worse outcomes; therefore, pre-operative vascular consultation and multidisciplinary management are highly recommended for better patient outcomes.

Percutaneous Thrombectomy with a Half-Deployed Stent for the Treatment of Acute Inferior Vena Cava Thrombosis.

Inferior vena cava (IVC) thrombosis, a type of deep vein thrombosis (DVT), is a relatively rare and poorly known disease compared to lower extremity DVT. We present a case of a 68-year-old woman with abdominal pain and mild lower leg swelling due to IVC thrombosis extending from the common iliac vein to the infrahepatic IVC. The thrombus was removed using a 14-mm Niti-S stent (Taewoong Medical, Korea) inserted via the right internal jugular vein. The stent was partially deployed and gently advanced to cover the thrombus, and then retracted through a vascular sheath capturing the thrombus. This case presents a therapeutic approach for the treatment of IVC thrombosis using a half-deployed stent as a filter and a basket. Follow-up evaluation after 5 years revealed a patent IVC and common iliac vein.

Outcomes after aortic aneurysm repair in patients with history of cancer: a nationwide dataset analysis.

BACKGROUND: Synchronous cancer in patients with abdominal aortic aneurysm (AAA) increases morbidity and mortality after AAA repair. However, little is known about the impact of the history of cancer on mortality after AAA repair. METHODS: Patients with intact AAA who were treated with endovascular aneurysm repair or open surgical repair were selected from the Health Insurance and Review Assessment data in South Korea between 2007 and 2016. Primary endpoints included the 30- and 90-day mortality and long-term mortality after AAA repair. The Cox proportional hazards models were constructed to evaluate independent predictors of mortality. RESULTS: A total of 1999 patients (17.0%, 1999/11785) were diagnosed with cancer prior to the AAA repair. History of cancer generally had no effect in short-term mortality at 30 and 90 days. However, short-term mortality rate of patients with a history of lung cancer was more than twice that of patients without it (3.07% vs. 1.06%, P = 0.0038, 6.14% vs. 2.69%, P = 0.0016). Furthermore, the mortality rate at the end of the study period was significantly higher in AAA patients with a history of cancer than in those without a history of cancer (21.21% vs. 17.08%, P < .0001, HR, 1.31, 95% CI, 1.17-1.46). CONCLUSIONS: The history of cancer in AAA patients increases long-term mortality but does not affect short-term mortality after AAA repair. However, AAA repair could increase both short- and long-term mortality in patients with lung cancer history, and those cases should be more carefully selected.

Optimal Prediction of the Central Venous Catheter Insertion Depth Targeting the Cavoatrial Junction.

BACKGROUND: Central venous catheters should be positioned at the cavoatrial junction or the right atrium. If catheters are inserted to a depth derived by adding the length between the needle insertion point and the clavicular notch and the length between the clavicular notch and the carina, the catheter tip can be placed near the carina. Based on this, we aim to make a formula to place a catheter tip near the cavoatrial junction. METHODS: This prospective nonrandomized interventional study included patients who needed a central venous catheter from June 2017 to July 2018. The location of the cavoatrial junction was identified using a fluoroscopic technique. The following variables were measured: L1, the length between the needle insertion point and the clavicular notch; L2, the length between the clavicular notch and the carina; and α, the length between the carina and the cavoatrial junction. RESULTS: A total of 70 patients were enrolled. The mean age was 65.5 ± 11.6 years, and 62.9% were male. The mean L1 and L2 were 7.6 ± 1.4 and 7.0 ± 1.4 cm, respectively. The mean α was 4.4 ± 1.5 cm (95% CI 4.1-4.8), and it was not affected by demographic factors, such as sex, age, height or weight. CONCLUSIONS: Central venous catheters in adult patients can be placed near the cavoatrial junction using a simple formula: the distance between the insertion point and the clavicular notch + the distance between the clavicular notch to the carina + 4.4 cm.

Modified Brachio-basilic/brachial Arteriovenous Fistula Creation with Short-segment Elevation Preserving the Axilla.

BACKGROUND: Brachio-basilic/brachial transposition arteriovenous fistula has emerged as one of the autologous arteriovenous fistula options. However, there have not been many reports on the outcomes of basilic or brachial elevation of arteriovenous fistula compared with those of conventional transposition. We evaluated the efficacy of modified brachio-basilic and brachio-brachial arteriovenous fistula creation with short-segment elevation preserving the axillary area. METHODS: From March 2016 to August 2018, medical records of the patients who underwent short-segment elevation of brachio-basilic or brachio-brachial arteriovenous fistula in the upper arm (sBAE or sBRE) were reviewed retrospectively. RESULTS: Of the 51 patients, 37 underwent sBAE and 14 underwent sBRE. Maturation failure occurred in two patients (3.92%), who underwent sBAE. Stenosis was the most common complication, which developed in 13 patients (25.5%), and there was no significant difference between the sBAE and the sBRE. In the 51 patients, cumulative primary patency rates at 6 and 12 months were 88.3% and 69.1%, respectively. Assisted primary patency rates at 6 and 12 months were 97.8% and 90.7%, respectively. Secondary patency rates at 6 and 12 months were both 100%. There were no significant differences between the sBAE and the sBRE in 1-year primary patency (79.1% vs. 46.7%; P = 0.20), assisted primary patency (91.6% vs. 88.1%; P = 0.36), and secondary patency rates (100% vs. 100%). CONCLUSIONS: Brachio-basilic/brachial arteriovenous fistula with short-segment elevation preserving the axilla showed excellent 1-year patency rate, easier cannulation, and other future advantages, and therefore, is a logical modification of conventional transposition of arteriovenous fistula.

Thrombosis of a Long-Segment Aneurysm from the Iliac to Popliteal Artery Associated with Arteriovenous Malformation and Varicose Veins.

A 58-year-old male patient with severe claudication due to thrombosis of the left ilio-femoro-popliteal artery aneurysm. He also had a venous stasis ulcer with a history of multiple embolotherapy of arteriovenous malformation. Duplex sonography revealed reflux and varicose veins of the left great saphenous vein (GSV). A sequential bypass surgery was performed that consisted of excision of the left external iliac and common femoral artery aneurysm, external iliac to deep femoral interposition with an expanded polytetrafluoroethylene graft, and femoro-posterior tibial artery bypass with the reversed left GSV. Symptoms of claudication were alleviated and the chronic ulcer was healed in time. To our knowledge, this is the first report of successful bypass in a patient with arterial aneurysm, arteriovenous malformation, and venous insufficiency that can be diagnosed as an atypical case of Parkes Weber syndrome. Long-term follow-up is needed to define the fate of aneurysms and varicose vein graft.

Association of Intrapatient Variability of Tacrolimus Concentration With Early Deterioration of Chronic Histologic Lesions in Kidney Transplantation.

BACKGROUND: High intrapatient variability (IPV) of tacrolimus (Tac) is increasingly recognized as a risk factor for poor graft outcomes in kidney transplantation. The timing of onset of its impact on kidney histologic lesions has not been investigated. METHODS: We analyzed the adverse effect of Tac IPV using the coefficient of variability from 6 to 12 months posttransplantation on long-term outcomes in a cohort of 671 kidney recipients and on the evolution of chronic histologic lesions in a cohort of 212 recipients for whom paired protocol biopsies at 10 days and 1 year were available. RESULTS: High IPV of Tac (cutoff value of coefficient of variability = median of 20.5%) was associated with an increased risk of graft loss (hazard ratio, 3.28; 95% confidence interval, 1.090-9.849; P = 0.035) in the entire cohort. At 1 year, the high Tac IPV group showed a significantly deteriorated chronicity score (F = 5.912, P = 0.016) compared with the low Tac IPV group in the Histology cohort after controlling for the 10-day scores. In a multivariate analysis, a high IPV of Tac was predictive of the chronicity score (odds ratio, 1.91; 95% confidence interval, 0.215-1.075; P = 0.003) at 1 year posttransplant. CONCLUSIONS: These data indicate that high IPV of Tac is associated with early deterioration of chronic histologic lesions as well as poorer long-term outcomes. Large prospective studies of Tac IPV usage as a clinical monitoring tool are needed in the future.

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.

Development of a novel linear model for predicting recipient's post-transplant serum creatinine level after living donor kidney transplantation: A multicenter cross-validation study.

BACKGROUND: This study was designed to develop and cross-validate a statistical model for predicting post-transplant serum creatinine of living donor kidney transplantation. MATERIALS AND METHODS: Adult recipients of living donor kidney transplantation from August 2012 to October 2017 at Samsung Medical Center (SMC) and Seoul National University Hospital (SNUH) with normal post-transplant protocol biopsy were included for modelling. Demographic data including recipient and donor's sex, age, body measurements and comorbidities, pre-transplant donor serum creatinine, graft weight, post-transplant recipient serum creatinine and the result of protocol biopsy were collected. Multivariate linear regression analysis was performed for developing the model based on SMC cohort. Internal validation was performed using leave-one-out cross-validation with the same cohort. External validation using leave-one-out cross-validation was performed based on the cohort of SNUH. RESULTS: A total of 238 and 191 recipients were included from SMC and SNUH, respectively. The prediction model included recipient's sex (ß = 0.228, P<0.001), height (ß = 0.007, P<0.001), and weight (ß = 0.006, P<0.001), donor's age (ß = 0.004, P<0.001), height (ß = -0.007, P<0.001), pre-transplant serum Cr (ß = 0.377, P<0.001) and graft weight (ß = -0.002, P<0.001). The model showed R2 of 0.708, root mean square error of prediction (RMSEP) of 0.161 and intraclass correlation coefficient (ICC) of 0.83. The internal validation showed predicted ICC of 0.82, RMSEP of 0.161, and accuracy was calculated 0.895. The external validation showed predicted ICC of 0.78, RMSEP of 0.170, and accuracy was calculated 0.876. CONCLUSIONS: The linear prediction model based on body measurement and donor serum creatinine and graft weight showed a high accuracy in cross-validation.