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Purpose: To investigate the physiological uptake of hybrid fluorine-18-fluorodeoxyglucose (FDG)–positron emission tomography/computed tomography (PET/CT) before and after an uncomplicated endovascular aneurysm sealing (EVAS) procedure as a possible tool to diagnose EVAS graft infection and differentiate from postimplantation syndrome. Materials and Methods: Eight consecutive male patients (median age 78 years) scheduled for elective EVAS were included in the prospective study ( ClinicalTrials.gov identifier NCT02349100). FDG-PET/CT scans were performed in all patients before the procedure and 6 weeks after EVAS. The abdominal aorta was analyzed in 4 regions: suprarenal, infrarenal neck, aneurysm sac, and iliac. The following parameters were obtained for each region: standard uptake value (SUV), tissue to background ratio (TBR), and visual examination of FDG uptake to ascertain its distribution. Demographic data were obtained from medical files and scored based on reporting standards. Results: Visual examination showed no difference between pre- and postprocedure FDG uptake, which was homogenous. In the suprarenal region no significant pre- and postprocedure differences were observed for the SUV and TBR parameters. The infrarenal neck region showed a significant decrease in the SUV and no significant decrease in the TBR. The aneurysm sac and iliac regions both showed a significant decrease in SUV and TBR between the pre- and postprocedure scans. Conclusion: Physiological FDG uptake after EVAS was stable or decreased with regard to the preprocedure measurements. Future research is needed to assess the applicability and cutoff values of FDG-PET/CT scanning to detect endograft infection after EVAS.

Objective Vascular prostheses for small caliber bypass grafts in cardiac and vascular diseases or for access surgery are still missing. Poly (Ɛ-caprolactone) (PCL) has been previously investigated by our group and showed good biocompatibility and mechanical properties in vitro and rapid endothelialisation, cellular infiltration and vascularisation in vivo yielding optimal patency in the abdominal aortic position. The aim of the present study is to evaluate our PCL graft in the carotid position and to compare its outcome to the grafts implanted in the abdominal aortic position. Methods PCL grafts (1 mm ID/10 mm long) were implanted into the left common carotid artery in 20 Sprague-Dawley rats and compared to our previously published series of abdominal aortic implants. The animals were followed up to 3, 6, 12 and 24 weeks. At each time point, in vivo compliance, angiography and histological examination with morphology were performed. Results PCL grafts showed good mechanical properties and ease of handling. The average graft compliance was 14.5 ± 1.7%/ mmHg compared to 7.8 ± 0.9% for the abdominal position and 45.1 ± 3.2%/ mmHg for the native carotid artery. The overall patency for the carotid position was 65% as compared to 100% in the abdominal position. Complete endothelialisation was achieved at 3 weeks and cell invasion was more rapid than in the aortic position. In contrast, intimal hyperplasia (IH) and vascular density were less pronounced than in the aortic position. Conclusion Our PCL grafts in the carotid position were well endothelialised with early cellular infiltration, higher compliance, lower IH and calcification compared to the similar grafts implanted in the aortic position. However, there was a higher occlusion rate compared to our abdominal aorta series. Anatomical position, compliance mismatch, flow conditions may answer the difference in patency seen.

Objective: Endograft mural thrombus has been associated with stent graft or limb thrombosis after endovascular aneurysm repair (EVAR). This study aimed to identify clinical and morphologic determinants of endograft mural thrombus accumulation and its influence on thromboembolic events after EVAR. Methods: A prospectively maintained database of patients treated by EVAR at a tertiary institution from 2000 to 2012 was analyzed. Patients treated for degenerative infrarenal abdominal aortic aneurysms and with available imaging for thrombus analysis were considered. All measurements were performed on three-dimensional center-lumen line computed tomography angiography (CTA) reconstructions. Patients with thrombus accumulation within the endograft's main body with a thickness >2 mm and an extension >25% of the main body's circumference were included in the study group and compared with a control group that included all remaining patients. Clinical and morphologic variables were assessed for association with significant thrombus accumulation within the endograft's main body by multivariate regression analysis. Estimates for freedom from thromboembolic events were obtained by Kaplan-Meier plots. Results: Sixty-eight patients (16.4%) presented with endograft mural thrombus. Median follow-up time was 3.54 years (interquartile range, 1.99-5.47 years). In-graft mural thrombus was identified on 30-day CTA in 22 patients (32.4% of the study group), on 6-month CTA in 8 patients (11.8%), and on 1-year CTA in 17 patients (25%). Intraprosthetic thrombus progressively accumulated during the study period in 40 patients of the study group (55.8%). Overall, 17 patients (4.1%) presented with endograft or limb occlusions, 3 (4.4%) in the thrombus group and 14 (4.1%) in the control group (P = .89). Thirty-one patients (7.5%) received an aortouni-iliac (AUI) endograft. Two endograft occlusions were identified among AUI devices (6.5%; overall, 0.5%). None of these patients showed thrombotic deposits in the main body, nor were any outflow abnormalities identified on the immediately preceding CTA. Estimated freedom from thromboembolic events at 5 years was 95% in both groups (P = .97). Endograft thrombus accumulation was associated with >25% proximal aneurysm neck thrombus coverage at baseline (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1-3.3), neck length = 30 mm (OR, 2.4; 95% CI, 1.3-4.6), AUI (OR, 2.2; 95% CI, 1.8-5.5), or polyester-covered stent grafts (OR, 4.0; 95% CI, 2.2-7.3) and with main component "barrel-like" configuration (OR, 6.9; 95% CI, 1.7-28.3). Conclusions: Mural thrombus formation within the main body of the endograft is related to different endograft configurations, main body geometry, and device fabric but appears to have no association with the occurrence of thromboembolic events over time.

Stent-graft migration and type I endoleaks are associated with a higher rate of reintervention and increased mortality and morbidity. This article describes a patient presented with an infrarenal aortic stent-graft which had migrated into the aortic sac with loss of all aortic neck attachment. The acutely expanding abdominal aortic aneurysm was treated by placing a second modular endograft within and above the migrated stentgraft. The patient returned 36 months later, with features of an acute myocardial infarction, severe bilateral lower limb ischemia, and renal failure. He was too ill for intervention and demised within 48 hours.

Secondary stent graft infection is a life-threatening complication after thoracic endovascular aortic repair (TEVAR). There is no consensus on optimal treatment strategy, but combined antibiotic and surgical treatment is advocated. Two years after his TEVAR procedure, a 70-year-old patient was admitted to the hospital with a secondary periaortic abscess. At first, the abscess was managed with clindamycin and transesophageal drainage. The abscess would not dissipate, and an infected iatrogenic aortoesophageal fistula was formed, which was surgically treated with esophageal resection, gastric tube reconstruction, and omental flap coverage.

Background Endovascular aneurysm repair of aortoiliac or iliac aneurysms is often performed with stent graft coverage of the origin of the hypogastric artery (HA) to ensure adequate distal seal. It is considered common practice to perform adjunctive coiling of the HA to prevent a type II endoleak. Our objective was to question the necessity of pre-emptive coiling by comparing the outcomes of HA coverage with and without prior coil embolization. Methods Data from the Endurant Stent Graft Natural Selection Global Postmarket Registry (ENGAGE), which prospectively enrolled 1263 endovascular aneurysm repair patients between March 2009 and April 2011 from multiple centers worldwide, were used for this study. We identified patients in whom the Endurant stent graft (Medtronic Vascular, Santa Rosa, Calif) covered one or both HAs and grouped them into cases in which prior HA embolization—coils or plugs—was performed (CE) and cases in which HA embolization was not performed (NE). The occurrence of covered HA-related endoleak and secondary interventions were compared between groups. Results In 197 patients, 225 HAs were covered. Ninety-one HAs were covered after coil embolization (CE group), and 134 HAs were covered without prior coil embolization (NE group). Both groups were similar at baseline and had comparable length of follow-up to last image (665.2 ± 321.7 days for CE patients; 641.6 ± 327.6 days for NE patients; P = .464). Importantly, both groups showed equivalent iliac morphology concerning common iliac artery proximal, mid, and distal dimensions and tortuosity, making them suitable for comparative analysis. During follow-up, HA-related endoleaks were sparse and occurred equally often in both groups (CE 5.5% vs NE 3.0%; P = .346). Secondary intervention to resolve an HA-related endoleak was performed twice in the CE group and three times in the NE group. Late non-HA-related endoleaks occurred more often in the CE group compared with the NE group, (25.0% vs 15.0%; P = .080). Secondary interventions for other reasons than HA-related endoleaks occurred in 7.5% of NE cases and 15.4% of CE cases ( P = .057), mostly for occlusions in the ipsilateral iliac limb. During follow-up, 19 NE patients and 9 CE patients died, which is not significantly different ( P = .225), and no deaths were related directly or indirectly to HA coverage. Also, no reports of gluteal necrosis and bowel ischemia were made. Conclusions This study shows that HA coverage with the Endurant endograft without prior coil embolization does not increase the incidence of endoleak or related secondary interventions. These findings together with the already available evidence suggest that omission of coil embolization may be a more resource-effective strategy whenever HA coverage is required.

Objectives\ud \ud New and re-designed stent grafts for endovascular aortic aneurysm repair (EVAR) are released regularly. Manufacturers use data from registries to assess stent graft performance, but little is known about the ability of such registries to detect rates of clinically relevant complications. The aim of this paper was to perform a systematic review and meta-analysis to determine pooled failure rates for EVAR stent grafts, to define an acceptable non-inferiority limit for these devices, and then to calculate the number of patients needed for a new device to achieve non-inferiority against published devices.\ud \ud \ud Data sources and review methods\ud \ud MEDLINE and EMBASE were searched for studies reporting outcomes of specific EVAR grafts being used for intact infrarenal abdominal aortic aneurysms, from inception to November 2016. Meta-regression was performed to pool data and calculate the patient numbers needed to detect non-inferiority of a future graft performance. An expert consensus was performed to define adequate standards for device safety.\ud \ud \ud Results\ud \ud One hundred and forty-seven moderate quality papers involving 27,058 patients were included. Multiple outcomes were pooled. Of these, the estimated rate (±standard error) of overall endoleak (excluding Type II) at 2 years was 5.7 ± 0.6%. The pooled re-intervention rate was 11.1 ± 0.7% at 2 years. There were differences in pooled endoleak rates between different stent graft types. Expert consensus defined non-inferiority as better performance than the worst performing 25% of stent grafts. The most popular outcome in the expert consensus was cumulative endoleak rate (excluding Type II). The number of patients who would need to be enrolled in a registry to demonstrate non-inferiority at this level was 525. Only two of 147 included studies achieved this. The second most popular choice in the expert consensus was re-intervention rate; 492 patients are required to demonstrate this.\ud \ud Conclusions\ud \ud Five hundred and twenty-five patients need to be entered into a registry to demonstrate non-inferiority to previous stent grafts. Almost all previous publications have captured lower patient numbers. With performance varying between devices, and new devices being introduced regularly, there is an urgent need to capture higher quality long-term data on EVAR stent grafts.

We report a case of ascending aortic graft infection by an atypical bacteria, Mycoplasma hominis, with mediastinitis, a dreaded complication after cardiac surgery. A 55-year-old patient underwent ascending aorta replacement for acute type A dissection. He developed sternal instability and purulent discharge, requiring sternal wire removal and debridement. Cultures were initially sterile, but showed M. hominis infection after a significant delay and in specific culture media. The patient was treated with doxycycline and moxifloxacine. Cultures became negative and the sternum was closed on the 28th postoperative day after the first debridement. Recovery was favorable, with no signs of infection. Antibiotics were continued for one year. The patient is still asymptomatic 16 months after antibiotic interruption. Atypical organisms should be considered in the differential diagnosis of acute mediastinitis of unknown etiology after routine microbiological investigations.