A nationwide study of regional preference and graft survival of kidney transplantation in South Korea: patterns of centralization in the capital area.

Purpose: This study aims to investigate regional patterns and graft survival rates in kidney transplantation (KT) within South Korea using the National Health Insurance Service database. Methods: By analyzing KT data from 2002 to 2017, including patient residency, KT location, and post-KT dialysis information, graft survival was assessed through post-KT dialysis and validated against Ulsan University Hospital and the Korean Organ Transplantation Registry's 2017 report. Results: Among the 20,978 KTs, 60.5% occurred in the Korean capital, Seoul, whereas 39.5% occurred outside. The overall graft survival rate was 81.5% with a median survival duration of 57 months. Patient survival was 83.8%, with a median survival duration of 61 months. For KTs from 2002 to 2007, the 10-year graft and patient survival rates were 89.1% and 90.3%, respectively. The KT recipients living outside Seoul who underwent the KT within their residential regions had a graft survival rate of 88.3%, and those receiving KTs outside their original region had a graft survival rate of 88.0%. Among Seoul residents who underwent KTs in the city, the graft survival rate was 90.5%. Importantly, hospital location did not significantly affect graft survival rates (P = 0.136). Conclusion: This study revealed a regional preference for KT in South Korea, particularly in the capital city, likely because of nonresidents. Nevertheless, the graft and patient survival rates showed no significant regional disparities. These findings emphasize the necessity for equitable KT service access across regions in order to optimize patient outcomes.

Outgrowing skin involvement in malakoplakia after kidney transplantation: A case report.

INTRODUCTION: Malakoplakia is a rare pseudotumor that arises in the context of recurrent infections, particularly in immunocompromised states. We report a case of renal allograft parenchymal malakoplakia. CASE REPORT: A 59-year-old woman successfully received a cadaveric renal transplant in June 2018. Two months after transplantation, she was treated for a urinary tract infection (UTI). In March 2019, she underwent allograft biopsy for increasing creatinine. The biopsy identified T cell mediated rejection and steroid pulse therapy was performed. In December 2019, she was hospitalized for right flank pain and pyuria, and her creatinine level was 1.9 mg/dL. Radiographic findings were suggestive of a hematoma or abscess in the perirenal area, and septated fluid collection was suspected. Biopsy results suggested malakoplakia, and von Kossa stain was positive for Michaelis- Gutmann bodies. Tissue culture demonstrated Escherichia coli, and this was treated with antibiotics. The dose of tacrolimus was reduced. The patient was discharged after 1 month of hospitalization and was maintained on oral antibiotics. Follow-up imaging revealed an increase in the extent of lesion into the adjacent abdominal wall. Assuming the case to be refractory, we performed surgical resection and abscess drainage. Although the renal parenchymal involvement persisted, the size showed a decreasing trend over 2 months of serial observation with ultrasonography. CONCLUSIONS: Malakoplakia should be considered as a differential diagnosis for recurrent UTI with graft dysfunction. Malakoplakia can be successfully treated with reduction in immunosuppression and medical therapy using long-term antibiotic treatment in most cases. However, early surgical treatment must be considered for refractory cases.

Association between Laterality and Location of Deep Vein Thrombosis of Lower Extremity and Pulmonary Embolism.

PURPOSE: The aim of this study was to investigate the relationship between the anatomical location of thrombi in the lower extremities and the development of pulmonary embolism (PE). MATERIALS AND METHODS: We collected and analyzed the data of patients diagnosed with deep vein thrombosis (DVT) of the lower extremities between 2006 and 2015, and included those whose computed tomography (CT) data were available for PE identification. We evaluated the relationship between the laterality and the proximal/distal location of the thrombi in lower extremites and the location of PE. RESULTS: CT images were available for 388/452 patients with DVT. After excluding 32 cases with bilateral involvement, 356 cases were included for analysis in this study. The ratio of DVT in the left:right leg was 232:124. PEs developed in 121 (52.2%) patients with left-sided DVT and in 78 (62.9%) with right-sided DVT (P=0.052). PEs in the main pulmonary arteries developed in 36 (15.5%) patients with left leg DVT and in 30 (24.2%) with right leg DVT (P=0.045). The most frequent site of thrombosis associated with the development of PE was the left iliac vein (59/199, 29.6%). According to the anatomical segment of the leg affected by DVT, patients with DVT in the right femoral vein (50/71, 70.4%; P=0.016) had the highest rate of occurrence of PE. CONCLUSION: PE develops more frequently in patients with right-sided DVT than in those with left-sided DVT. Therefore, careful observation for the possible development of PE is recommended in cases with right-sided DVT of the lower extremity.

Relationship between the optimal cut-off values of anthropometric indices for predicting metabolic syndrome and carotid intima-medial thickness in a Korean population.

Anthropometric measurements are simple and useful methods for predicting metabolic syndrome (MetS) because obesity is a predominant feature of MetS. Although carotid intima-medial thickness (IMT) is generally used to evaluate subclinical atherosclerosis, the relationship between the optimal cut-off anthropometric values for predicting MetS and carotid IMT has not been analyzed in a Korean population.Anthropometric measurements including waist circumference (WC), waist hip ratio (WHR), waist height ratio (WHtR), body mass index (BMI), and carotid IMT were assessed in 2560 Korean subjects without previous history of cardiovascular disease, cerebrovascular disease, neurological abnormalities, or malignancy who participated in baseline health examinations in a self-referral setting in the Seoul area between April 2010 and November 2012. MetS was defined using the National Cholesterol Education Program-Adult Treatment Panel III criteria.In both men and women, the levels of all anthropometric indices were significantly higher in subjects with MetS than in those without MetS. According to the receiver operating characteristic curve, the values of 80.8 cm for WC, 0.87 for WHR, 0.52 for WHtR, and 24.6 kg/m for BMI were the optimal cut-offs for predicting MetS in women. The values of 89.3 cm for WC, 0.90 for WHR, 0.52 for WHtR, and 25.1 kg/m for BMI were the optimal cut-offs for predicting MetS in men. After adjusting for confounding factors, the WC optimal cut-off values for predicting MetS were independently associated with carotid IMT in both women and men (women: ß = 0.016, P = .008; men: ß = 0.033, P = .009). The optimal BMI cut-off value was independently associated with carotid IMT in men only (ß = 0.027, P = .032).Among anthropometric indices including WC, WHR, WHtR, and BMI, the WC optimal cut-off values for MetS were independently associated with an increased carotid IMT in both women and men in a Korean population.

Factors of Acute Kidney Injury Donors Affecting Outcomes of Kidney Transplantation From Deceased Donors.

BACKGROUND: This study aimed to investigate the outcomes of kidney transplantation (KT) from deceased acute kidney injury (AKI) donors and analyzed the factors affecting these outcomes. METHODS: All patients who underwent KT from deceased donors at our institution from 1998 to 2016 were retrospectively reviewed. Recipients were divided into the AKI and non-AKI donor groups. We analyzed delayed graft function (DGF), serum creatinine levels at 1 month and 1 year after KT, cold ischemia time, donors' initial and terminal serum creatinine levels, Kidney Donor Profile Index, and patient and graft survival in each group. RESULTS: Of 181 recipients, 30 received kidneys from 21 AKI donors, whereas the remaining 151 received kidneys from donors without AKI. DGF more frequently developed in the AKI donor group than in the non-AKI donor group (40% vs 7.28%; P = .001). Allograft functions at 1 month and 1 year after KT did not differ between the AKI and non-AKI donor groups (1 month: P = .469; 1 year: P = .691). Factors affecting DGF were recipient weight and donor AKI. Recipient factors affecting graft function at 1 year were recipient height, length of hospital stay, serum creatinine levels at 1 month and 6 months, and biopsy-proven acute rejection. Older donor age was the only donor factor that affected graft function at 1 year. CONCLUSION: KT from deceased AKI donors showed a higher DGF rate but favorable patient and graft survival and graft functions. Donor AKI and recipient weight affected DGF, and only older donor age affected graft function at 1 year.

Association of baseline histopathology and kidney donor risk index with graft outcomes in deceased donor kidney transplantation
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BACKGROUND: Donor organ quality is a key determinant of graft outcomes in deceased donor kidney transplantation (DDKT). The predictive values of baseline histopathology and several clinical scoring systems for long-term graft outcomes have been evaluated, but the results remain controversial. MATERIALS AND METHODS: We screened 167 patients who underwent DDKT at Ulsan University Hospital from April 2003 to June 2016. Among them, 66 patients who underwent baseline kidney biopsy and whose kidney donor risk index (KDRI) was available were included in this analysis. All baseline biopsies were rescored according to the updated Banff classification. RESULTS: Median follow-up was 22 months. Mean age of recipients and donors was 51.4 and 44.7 years, respectively. Mean KDRI was 1.40 ± 0.44. During follow-up, delayed graft function and biopsy-proven acute rejection (BPAR) developed in 7 and 11 patients, respectively. Graft failure occurred in 2 patients. In Cox regression analysis, interstitial fibrosis/tubular atrophy (IFTA) (hazard ratio (HR) = 3.59; p = 0.049) was a significant risk factor for BPAR. In multivariate linear regression, age (standardized ß (SB) = -0.282; p = 0.002), BPAR (SB = -0.406; p < 0.001), KDRI (SB = -0.277; p = 0.003), and IFTA (SB = -0.298; p = 0.001) were significant predictors of last-visit estimated glomerular filtration rate (eGFR). CONCLUSION: Several clinical and pathologic parameters, such as KDRI and IFTA, may be helpful for predicting long-term graft outcomes, including BPAR and last-visit eGFR, in DDKT.
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Kidney Donation From a Patient Who Underwent Endovascular Aneurysm Repair.

Organ shortage is the greatest challenge facing the field of organ transplantation in Korea. There are no reports of patients who have undergone endovascular aneurysm repair being considered as kidney donors. We successfully performed kidney transplant procedures in a 62-year-old man and a 57-year-old man using kidneys recovered from a 67-year-old female brain-dead donor who underwent endovascular aneurysm repair 6 months before organ retrieval. To the best of our knowledge, this is the first report of transplants performed with organs from a donor who previously underwent endovascular aneurysm repair.

Outcomes of Spontaneous Isolated Superior Mesenteric Artery Dissection Without Antithrombotic Use.

OBJECTIVES: This study aimed to show the intention to treat results of treatment for spontaneous isolated superior mesenteric artery dissection (SISMAD) without anticoagulation or antiplatelet agents and the follow-up results of SISMAD according to the configuration on computed tomography (CT) scans. DESIGN: Retrospective, observational single centre study METHODS: All cases of SISMAD were enrolled consecutively from 2006 onwards. There were 25 symptomatic and four asymptomatic patients in whom SISMAD was found incidentally. The SISMAD patients were treated using a consistent therapeutic strategy without antithrombotics. SISMAD was categorized into four types based on the configuration on CT scans by Yun's classification. Follow-up CT was performed at 3 months, 6 months, and yearly thereafter. RESULTS: The median follow-up duration was 57 months (13-129 months). Improvement or complete resolution on CT scans, with no symptom recurrence, was seen in 27 patients. The non-invasive approach failed in three cases and two patients underwent further intervention. No patient died during the follow-up. CONCLUSIONS: Weighing the risks versus benefits of antithrombotics and considering the benign nature of SISMAD, conservative treatment without antithrombotics might be sufficient in patients without evidence of bowel ischaemia or infarction on initial CT scan.

Incidence, prevalence, mortality and causes of death in Takayasu Arteritis in Korea - A nationwide, population-based study.

BACKGROUND: Studies investigating the epidemiology and mortality of Takayasu Arteritis (TA) are scarce. The objective of this study was to provide information regarding the epidemiology of TA, such as the incidence, prevalence, survival and cause of death in Korea. METHODS: We used a national, population-based database maintained by the Rare Intractable Disease registration program and the Health Insurance Review and Assessment Service, which includes information on all TA patients, diagnosed based on uniform criteria. We also used data from Statistics Korea linked with RID database to confirm survival and cause of death. We analyzed data for the period 2008-2012. RESULTS: During study period, there were 612 new patients with TA, with a female-to-male ratio of 4.3:1. The annual mean incidence was 0.24 per 105 people, and the prevalence was 2.82 per 105 people in 2012. The average annual mortality rate was 0.02 per 105 people, and the standardized mortality ratio was 3.1. The overall survival of patients with TA was 96.6%, which was significantly lower than that in the general population. Cardiovascular disease was the most common cause of death, accounting for 29 of the 64 deaths (45.3%), followed by neoplasms in 9 patients (14.1%). CONCLUSIONS: The incidence and prevalence presented in this study are the highest ever reported. The survival of patients with TA was significantly lower than that of the general population, and the main cause of death was cardiovascular disease. This study reflects the need for greater awareness of TA, especially in Asian countries.

Impact of a preoperative evaluation on the outcomes of an arteriovenous fistula.

PURPOSE: The aim of this study was to determine the possible predictors of primary arteriovenous fistula (AVF) failure and examine the impact of a preoperative evaluation on AVF outcomes. METHODS: A total of 539 patients who underwent assessment for a suitable site for AVF creation by physical examination alone or additional duplex ultrasound were included in this study. Demographics, patient characteristics, and AVF outcomes were analyzed retrospectively. RESULTS: AVF creation was proposed in 469 patients (87.0%) according to physical examination alone (351 patients) or additional duplex ultrasound (118 patients); a prosthetic arteriovenous graft was initially placed in the remaining 70 patients (13.0%). Although the primary failure rate was significantly higher in patients assessed by duplex ultrasound (P = 0.001), ultrasound information changed the clinical plan, increasing AVF use for dialysis, in 92 of the 188 patients (48.9%) with an insufficient physical examination. Female sex and diabetes mellitus were risk factors significantly associated with primary AVF failure. Because of different inclusion criteria and a lack of adjustment for baseline differences, Kaplan-Meier survival analysis showed better AVF outcomes in patients assessed by physical examination alone; an insufficient physical examination was the only risk factor significantly associated with AVF outcomes. CONCLUSION: Routine use of duplex ultrasound is not necessary in chronic kidney disease patients with a satisfactory physical examination. Given that female gender and diabetes mellitus are significantly associated with primary AVF failure, duplex ultrasound could be of particular benefit in these subtypes of patients without a sufficient physical examination.

A Retrospective 10-Year, Single-Institution Study of Carotid Endarterectomy with a Focus on Elderly Patients.

BACKGROUND AND PURPOSE: This study evaluated the outcome following surgery for carotid artery stenosis in a single institution during a 10-year period and the relevance of aging to access to surgery. METHODS: Between January 2001 and December 2010, 649 carotid endarterectomies (CEAs) were performed in 596 patients for internal carotid artery occlusive disease at our institution; 596 patients received unilateral CEAs and 53 patients received bilateral CEAs. Data regarding patient characteristics, comorbidities, stroke, mortality, restenosis, and other surgical complications were obtained from a review of medical records. Since elderly and high-risk patients comprise a significant proportion of the patient group undergoing CEAs, differences in comorbidity and mortality were evaluated according to age when the patients were divided into three age groups: <70 years, 70-79 years, and ≥80 years. RESULTS: The mean age of the included patients was 67.5 years, and 88% were men. Symptomatic carotid stenosis was observed in 65.7% of patients. The rate of perioperative stroke and death (within 30 days of the procedure) was 1.84%. The overall mortality rate was higher among patients in the 70-79 years and >80 years age groups than among those in the <70 years age group, but there was no significant difference in stroke-related mortality among these three groups. CONCLUSIONS: CEA over a 10-year period has yielded acceptable outcomes in terms of stroke and mortality. Therefore, since CEA is a safe and effective strategy, it can be performed in elderly patients with acceptable life expectancy.

Renal autotransplantation in open surgical repair of suprarenal abdominal aortic aneurysm.

Although the standard treatment of abdominal aortic aneurysm has shifted from open surgery to endovascular repair, open surgery has remained the standard of care for complex aneurysms involving the visceral arteries and in patients unsuitable for endovascular aneurysm repair. Postoperative renal insufficiency may occur after open surgical repair of suprarenal abdominal aortic aneurysm. Methods of minimizing renal ischemic injury include aortic cross-clamping and renal reconstruction techniques. This report describes the use of renal autotransplantation for renal reconstruction during open surgical repair of a suprarenal abdominal aortic aneurysm. This technique was successful, suggesting its feasibility for open suprarenal abdominal aortic aneurysm repair, minimizing renal ischemic injury and optimizing postoperative renal function.

Use of cryopreserved cadaveric arterial allograft as a vascular conduit for peripheral arterial graft infection.

Major peripheral arterial graft infection is a potentially devastating complication of vascular surgery, associated with significant mortality and high amputation rates. Autologous saphenous veins are considered optimal arterial conduits for lower extremity revascularization in infected fields, but they are often unavailable or unsuitable in these patients. This study describes two patients with major peripheral graft infection, but without available autologous veins, who underwent graft excision and cryopreserved cadaveric arterial allograft reconstruction. Although long-term graft durability is unclear because of gradual deterioration and degeneration, these findings suggest that cadaveric allografts may be good options for patients with major peripheral graft infection.

Clinical outcome of early relaparotomy after elective open repair of abdominal aortic aneurysms.

PURPOSE: The aim of this study was to retrospectively evaluate the association of need for early relaparotomy with clinical outcomes after elective open repair of abdominal aortic aneurysms (AAAs). METHODS: A total of 292 consecutive patients who underwent elective open AAA repair at Asan Medical Center from January 2001 to December 2010 were included in this study, and we compared the demographics, clinical characteristics, related risk factors, and clinical outcomes of early relaparotomy versus nonrelaparotomy patients. RESULTS: The incidence of early relaparotomy during a single hospital stay was 4.1% (n = 12), and the most common causes were bowel ischemia (n = 5, 41.7%) and postoperative bleeding (n = 3, 25.0%). Among the demographics and clinical characteristics significantly associated with relaparotomy were: age (P = 0.025), chronic obstructive pulmonary disease (COPD) (P = 0.010), number of RBC units transfused during the AAA repair (P = 0.022) and in the following week (P = 0.005), and length of intensive care (P < 0.001) and overall hospital stay (P < 0.001). On multivariate analysis, presence of COPD (P = 0.009) and number of RBC units transfused during the AAA repair (P = 0.006) were statistically significantly associated with relaparotomy. Furthermore, early relaparotomy was associated with perioperative (within 30 days) (P = 0.048) and overall in-hospital mortality (P = 0.001). CONCLUSION: Early relaparotomy has an adverse effect on clinical outcomes: increased mortality and hospital length of stay. Presence of COPD and need for RBC transfusion are associated with early relaparotomy.

Bone marrow-derived progenitor cells in de novo liver regeneration in liver transplant.

The study was designed (1) to examine the hypothesis that circulating progenitor cells play a role in the process of de novo regeneration in human liver transplants and that these cells arise from a cell population originating in, or associated with, the bone marrow and (2) to investigate whether the transplanted liver volume has an effect on the circulating recipient-derived progenitor cells that generate hepatocytes during this process. Clinical data and liver tissue characteristics were analyzed in male individuals who underwent sex-mismatched adult-to-adult living donor liver transplantation using dual left lobe grafts. Dual left lobe grafts were examined at the time of transplantation and 19 to 27 days after transplantation. All recipients showed recovery of normal liver function and a significant increase in the volume of the engrafted left lobes after transplantation. Double staining for a Y-chromosome probe and the CD31 antigen showed the presence of hybrid vessels composed of recipient-derived cells and donor cells within the transplanted liver tissues. Furthermore, CD34-expressing cells were observed commingling with Y-chromosome+ cells. The ratio of recipient-derived vessels and the number of Y+ CD34+ cells tended to be higher when smaller graft volumes underwent transplantation. These findings suggest that the recruitment of circulating bone marrow-derived progenitor cells could contribute to vessel formation and de novo regeneration in human liver transplants. Moreover, graft volume may be an important determinant for the active mobilization of circulating recipient-derived progenitor cells and their contribution to liver regeneration.

Impact of graft composition on the systemic inflammatory response after an elective repair of an abdominal aortic aneurysm.

PURPOSE: The present study aimed to evaluate the risk factors and the role of graft material in the development of an acute phase systemic inflammatory response, and the clinical outcome in patients who undergo endovascular aneurysm repair (EVAR) or open surgical repair (OSR) of an abdominal aortic aneurysm (AAA). METHODS: We retrospectively evaluated the risk factors and the role of graft material in an increased risk of developing systemic inflammatory response syndrome (SIRS), and the clinical outcome in patients who underwent EVAR or OSR of an AAA. RESULTS: A total of 308 consecutive patients who underwent AAA repair were included; 178 received EVAR and 130 received OSR. There was no significant difference in the incidence of SIRS between EVAR patients and OSR patients. Regardless of treatment modality, SIRS was observed more frequently in patients treated with woven polyester grafts. Postoperative hospitalization was significantly prolonged in patients that experienced SIRS. In multivariate analyses, the initial white blood cell count (P = 0.001) and the use of woven polyester grafts (P = 0.005) were significantly associated with an increased risk of developing SIRS in patients who underwent EVAR. By contrast, the use of woven polyester grafts was the only factor associated with an increased risk of developing SIRS in patients who underwent OSR, although this was not statistically significant (P = 0.052). CONCLUSION: The current study shows that the graft composition plays a primordial role in the development of SIRS, and it leads to prolonged hospitalization in both EVAR and OSR patients.

Clinical outcomes related to the level of clamping in inferior vena cava surgery.

OBJECTIVE: In most cases of inferior vena cava (IVC) surgery, IVC clamping is required owing to several factors, including renal cell carcinoma with IVC thrombus extension and IVC leiomyosarcoma. Various clinical results were compared following IVC clamping by classifying clamping levels into juxtarenal, infrahepatic, and suprahepatic. In particular, the risk factors of postoperative thrombosis after IVC clamping were assessed comparatively. METHODS: Eighty-four patients who underwent IVC clamping owing to IVC pathology between 2002 and 2012 were retrospectively reviewed with regard to RBC transfusion, operation time, clamping time, liver and kidney functions, duration of hypotension, blood pressure (BP) drops, pulmonary thromboembolism (PTE), venous thrombosis, ICU stay duration, hospital stay duration, 30-day morbidity, and 30-day mortality. In addition, various clinical results were compared when postoperative thrombosis occurred after IVC clamping. RESULTS: Values for operation time, clamping time, units of RBC transfused, duration of hypotension, severity of BP drops, use of cardiopulmonary bypass (CPB), aspartate aminotransferase, the use of inotropes, IVC patency, ICU stay, and hospital stay duration were significantly higher in the suprahepatic clamping group than in the other clamping groups. In addition, CPB use and IVC clamping level were significant risk factors for postoperative thrombosis after IVC clamping. CONCLUSIONS: Although IVC clamping is a prerequisite for IVC surgery, operative durations, units of RBC transfused, and length of hospital stays increase with higher clamping levels. In addition, CPB use and IVC clamping level are significant risk factors for postoperative thrombosis. In IVC surgery with higher clamping levels, prompt hemodynamic support and proper anticoagulation therapy are important.

Stenosis or Occlusion of the Right Subclavian and Common Carotid Arteries Is More Common than That of the Innominate Artery in Takayasu Arteritis.

PURPOSE: The aim of this study was to introduce the phenomenon that stenosis or occlusion occurs less frequently in the innominate artery than in the right subclavian and common carotid arteries, which are not first-order branches of the aorta, in Takayasu arteritis (TA). MATERIALS AND METHODS: We retrospectively reviewed the medical records and image findings of all patients who were diagnosed with TA from 2006 to 2014. Two vascular surgeons and two radiologists interpreted the images by disease character, location, and extent of occlusion based on computed tomography angiography, magnetic resonance angiography, or digital subtraction arteriography. We have also reviewed the literature on arterial involvement in TA. RESULTS: A total of 42 patients were diagnosed with TA. The mean age was 43.9 years, and 83.3% (35/42) of the patients were women. The left subclavian artery was the most common stenosis or occlusion site (17, 40.5%) among the aortic branches. The innominate artery was a less common site (3, 7.1%) than the right subclavian artery (4, 9.5%) and the right common carotid artery (9, 21.4%). All innominate artery cases were found after endovascular procedures of the right subclavian or common carotid arteries. CONCLUSION: The innominate artery might develop stenosis or occlusion less frequently than the right subclavian and common carotid arteries in Korean TA patients.

Clinical outcomes of carotid endarterectomy in patients with carotid artery tandem lesions.

BACKGROUND AND PURPOSE: When carotid artery tandem lesions are present, the benefits of carotid endarterectomy (CEA) to reduce recurrent stroke remain uncertain. The present retrospective cohort study aimed to determine the clinical outcomes of CEA for carotid artery tandem stenosis that was diagnosed by contrast-enhanced magnetic resonance angiography. METHODS: Six hundred forty-seven consecutive patients underwent CEA between January 2001 and December 2010. Tandem stenosis, defined as a significant carotid bifurcation stenosis and identifiable stenosis of ≥50% of any downstream distal cerebral artery, was identified in 92 patients (14.2%) by contrast-enhanced magnetic resonance angiography. Patients with and without tandem stenosis were compared in terms of CEA outcomes. The primary end point was the composite of any stroke, myocardial infarction, or death during the periprocedural period or ipsilateral stroke within 4 years after CEA. RESULTS: Tandem stenosis did not associate with ipsilateral stroke during postoperative follow-up. The 2 groups did not differ in terms of estimated 4-year primary end point rates (8.7% versus 3.8%; P=0.07) or ipsilateral stroke-free (P=0.56), any stroke-free (P=0.89), or overall survival (P=0.41) rates. CONCLUSIONS: After diagnosis by contrast-enhanced magnetic resonance angiography, patients with and without tandem stenosis had similar rates of stroke and death.