Editor's Choice - Renal complications after EVAR with suprarenal versus infrarenal fixation among all users and routine users.

BACKGROUND: Previous studies comparing endografts with suprarenal and infrarenal fixation for endovascular abdominal aortic aneurysm repair (EVAR) have found conflicting results and did not account for differences in patient selection. This study aims to evaluate the differences in outcomes among surgeons who routinely use either suprarenal or infrarenal fixation, as well as all surgeons in the Vascular Study Group of New England (VSGNE). METHODS: All patients undergoing EVAR in the VSGNE from 2003 to 2014 were identified. All ruptured aneurysms, repairs with concomitant procedures, and infrequently used stent grafts (<50) were excluded. Suprarenal endografts included Talent, Zenith, and Endurant; infrarenal endografts included AneuRx and Excluder. Grafts were compared among surgeons who used only one type of endograft (suprarenal or infrarenal) for >80% of cases, as well as all surgeons. Multivariate regression and Cox hazard models were utilised to account for patient demographics, comorbidities, operative differences, and procedure year. RESULTS: This study identified 2574 patients (suprarenal, 1264; infrarenal, 1310) with 888 endografts placed by routine users (suprarenal, 409; infrarenal, 479). There were no differences in baseline comorbidities, including the estimated glomerular filtration rate, between suprarenal and infrarenal fixation, or between patients with endografts placed by routine and non-routine users. Patients treated with suprarenal endografts received more contrast than all users (102 mL vs. 100 mL, p = .01) and routine users (110 mL vs. 88 mL, p < .01), but other vascular and operative details were similar. Among all users, patients treated with suprarenal grafts had higher rates of creatinine increase >.5 mg/dL (3.7% vs. 2.0%, p = .01), length of stay >2 days (27% vs. 19%, p < .01), and discharge to a skilled nursing facility (9.2% vs. 6.7%, p = .02). There were no differences in 30 day or 1 year mortality. Following adjustment, suprarenal stent grafts remained associated with an increased risk of renal deterioration (OR 2.0; 95% CI 1.2-3.4) and prolonged length of stay (OR 1.8; 95% CI 1.4-2.2). Among routine users, suprarenal fixation was also associated with higher rates of renal dysfunction (3.7% vs. 1.3%, p = .02; OR 2.9; 95% CI 1.1-7.8). CONCLUSION: Despite potential differences in patient selection, endografts with suprarenal fixation among all users and routine users were associated with higher rates of renal deterioration and longer length of hospital stay. Longer-term data are needed to determine the duration and severity of renal function decline and to identify potential benefits of decreased migration or endoleak.

Predictors of early graft failure after infrainguinal bypass surgery: a risk-adjusted analysis from the NSQIP.

INTRODUCTION AND OBJECTIVES: Infrainguinal bypass surgery (BPG) is accompanied by significant 30-day mortality and morbidity, including early graft failure. The goal of this study is to identify patient- and procedure-specific factors which predict the rate of early graft failure in contemporary practice. METHODS: Data was obtained from the private sector National Surgical Quality Improvement Program, a prospective, validated database collected between 2005 and 2008 from 211 hospitals, using primary and modifier Current Procedural Terminology codes for BPG. The primary endpoint was graft failure at 30 days. Procedural parameters, patient demographics and clinical variables were analyzed by univariate and multivariate methods. RESULTS: There were 9217 BPG procedures (limb salvage, 49%; infrapopliteal distal anastomosis, 43%; prosthetic 32%) with patient variables: age 67 ± 12 years, male 64%, diabetes 44%, dialysis 7.4%. Mortality was 2.4%, major morbidity was 17.3%, and graft failure rate was 6.3% at 30 days. Multivariate predictors of graft failure demonstrated correlation (p-value, OR) with female gender (p = 0.0054, 1.29), limb salvage indication (p < 0.0001, 1.60), infrapopliteal anastomosis (p < 0.0001, 2.15), composite graft (p = 0.0436, 1.82), current smoking (p = 0.0007, 1.36), impaired sensorium (p = 0.0075, 2.13), emergency procedure (p < 0.0001, 2.03), previous vascular procedure (p = 0.0005, 1.39), and platelets >400K (p = 0.0019, 1.49). High-risk composite constructs utilizing these significant predictive factors can identify cohorts of patients with up to a 98-fold increase in odds of early graft failure. CONCLUSIONS: These results describe common risk factors that correlate with early graft thrombosis including the unique description of its association with thrombocytosis. Additional risk factors thus identify a subset of patients who are at highest risk for early BPG failure. This data may be used to refine patient selection.

The universal NF-kappaB inhibitor a20 protects from transplant vasculopathy by differentially affecting apoptosis in endothelial and smooth muscle cells.

Transplant vasculopathy (TV) is an accelerated form of atherosclerosis resulting in chronic rejection of vascularized allografts. The causes of TV are multifactorial and integrate at the level of the vascular wall, leading to a phenotypic switch of endothelial cells (ECs) and smooth muscle cells (SMCs). A20 is a NF-kappaB-dependent stress response gene in ECs and SMCs with potent anti-inflammatory effect in both cell types through blockade of NF-kappaB. A20 expression in ECs and SMCs correlates with the absence of TV in rat kidney allografts and long-term functioning human kidney allografts. We demonstrate that A20 protects ECs from tumor necrosis factor, Fas, and natural killer cell-mediated apoptosis by inhibiting proteolytic cleavage of caspase 8. A20 also safeguards ECs from complement-mediated necrosis. Hence, effectively shutting down cell death pathways initiated by inflammatory and immune offenders associated with TV. In contrast, A20 sensitizes SMCs to cytokine and Fas-mediated apoptosis through a novel nitric oxide (NO)-dependent mechanism. The unexpected proapoptotic effect of A20 in SMCs translates in vivo by the regression of established neointimal carotid lesions following balloon angioplasty in rats. Antedating apoptosis of SMCs, expression of the inducible NO synthase increases in A20-expressing neointimal SMCs, corroborating the involvement of NO in causing the proapoptotic effect of A20 in SMCs. Combined anti-inflammatory and anti- or proapoptotic functions of A20 in ECs and SMCs respectively qualify the positive effect of A20 upon vascular remodeling and healing. We propose that A20-based therapies may be effective in prevention and treatment of TV.