The acute impact of baseline renal function and contrast medium volume/estimated glomerular filtration rate ratio on reduced renal function following endovascular abdominal aortic aneurysm repair

Objective The aim of this study was to determine the acute impact of baseline serum creatinine, estimated glomerular filtration rate (eGFR), and contrast medium volume (CMV) on the incidence of reduced renal function (RRF) after endovascular abdominal aortic aneurysm repair (EVAR). We aimed to determine if the CMV/eGFR ratio was a predictor of RRF. Methods This study is a retrospective review of EVAR patients in the Society for Vascular Surgery/Vascular Quality Initiative (SVS/VQI) from January 2015 to August 2020. Reduced renal function was defined as > 0.3 mg/dl (26.5 μmol/L), 50% increase from baseline, and temporary or permanent dialysis. Receiver operator characteristic (ROC) curve analyses were conducted for serum creatinine, eGFR, contrast volume, fluid volume, and CMV/eGFR ratio. Two data sets (training and test) were developed followed by multivariate analyses. Results SVS/VQI data for EVAR contained 38,701 records, of which 30,539 were divided into training ( n = 18,283; 60%) and test ( n = 12,256; 40%) data sets. RRF rate for the training set was 3.6% ( n = 667) and 3.4% ( n = 420) for the test data. RRF patients included more females (29.4 vs 19.0%, p < 0.001), were older in age (75.6 + 8.4 vs 73.3 + 8.7 years), had more congestive heart failure (22.3 vs 12.2%, p < 0.001), and more COPD (42.0 vs 34.2%, p < 0.001). An ROC analysis revealed that eGRF, creatinine, contrast, intravenous fluid, and contrast medium volume (CMV)/eGFR ratio were all significantly ( p < 0.05) correlated with RRF. The eGFR and CMV/eGFR ratio had the largest area under the curve, (0.26) and (0.65), respectively, while fluid had the lowest (0.54). Negative predictive values were 93.7 (CMV/eGFR), 93.9 (creatinine), 94.2 (eGFR), 92.8 (contrast), and 92.6 (intravenous fluid). Multivariate analysis of the training data set resulted in the CMV/eGFR ratio as an independent predictor of RRF (odds ratio, OR: 1.9 with 95% CI: 1.6, 2.2, p < 0.015). For the test data, the CMV/eGFR ratio was an independent predictor of RRF (OR: 1.8, CI: 1.4 to 2.2, p < 0.001) as well as several other variables. Conclusion RRF after EVAR is a dreaded and potentially devastating complication. Baseline serum creatinine, eGFR, contrast medium volume, and the ratio (CMV/eGFR) were all significantly associated with RRF. The optimal cut-off value for the CMV/eGFR ratio, ≤ 2, provides an easy-to-use equation to provide a suggested contrast target based on initial renal function with caution applied for high-risk patients.

Abdominal aortic endograft infection with Clostridium difficile

Objectives The increase in endovascular aortic aneurysm repair has led to increasing incidence of aortic endograft infections. Additionally, more atypical organisms are being identified as pathogens. We report on a rare aortic endograft infection to further characterize and understand these infections. Methods We report a Clostridium difficile culture–positive aortic endograft infection in an 82-year-old male 3 years after endovascular abdominal aortic aneurysm repair. Results The patient underwent successful open, complete explant of his endograft and in-situ repair using a rifampin-soaked Dacron graft. He continues to do well. Conclusions Aortic endograft infections are a complex problem further complicated by rare and virulent infections. Unless the patient is at prohibitive risk, the management of infected aortic endografts is surgical graft explant and in-situ or extra-anatomic reconstruction due to the exceedingly high mortality rate with non-operative management.

A Rare Case of Aortoenteric Graft Erosion Presenting as Candida glabrata Fungemia

Background. An aortoenteric fistula (AEF) describes a communication of the aorta or aortic graft with an adjacent loop of the bowel. Aortic graft erosion is a rare complication of abdominal aortic aneurysm repair. We describe a case of a patient presenting with sepsis from Candida glabrata fungemia secondary to aortoenteric erosion without any symptoms or signs of gastrointestinal bleeding. This is a unique case of Candida glabrata fungemia from aortoenteric graft erosion. Case Summary. This patient is a 75-year-old male with a history of a prior aortobifemoral bypass graft in 2005. He presented with complaints of right paraspinal pain and chills. He had no symptoms of gastrointestinal bleeding or abdominal pain. His white blood cell count was 25,600/mcl (4,000–11,000/mcL) with left shift. The erythrocyte sedimentation rate was 11 mm/hr (0-38 mm/hr), and C-reactive protein was 95.5 mg/L (<=10.0 mg/L). Blood cultures were obtained and eventually grew Candida glabrata. A computed tomography angiogram (CTA) of abdomen and pelvis demonstrated inflammation surrounding the graft concerning for graft infection with additional inflammatory changes tracking down both femoral limbs. He underwent staged bilateral femoralaxillary bypass followed by the excision of aortobifemoral bypass. Conclusion. Patients with aortoenteric erosion can present with sepsis in absence of gastrointestinal bleeding. Emergent computed tomography angiogram (CTA) of abdomen and pelvis should be performed to assess for aortic graft erosion or fistula. Empiric treatment with antibiotics should include antifungal agent like micafungin until the final culture is reported. The definite management is an extra anatomic bypass, followed by graft excision.