Complete excision in patients with aortic vascular graft and endograft infections (VGEIs) is a significant undertaking and many patients never undergo definitive treatment. Knowing their fate is ...important to be able to assess the risks of graft excision vs alternative strategies. This study analyzed their life expectancy and sepsis-free survival.
VGEIs were diagnosed according to the Aortic Graft Infection (MAGIC) criteria and patients turned down for graft removal from November 2006 to December 2020 were included. Primary endpoints were aortic-related and sepsis-free survival estimated using the Kaplan-Meier method. A Cox proportional hazards regression analysis was used to compute the hazard ratio (HR) and 95% confidence interval (CI) as estimates of survival without sepsis.
Seventy-four patients were included, median age 71 years (63-79). The index aortic repair was either open (n=33; 44.6%), endovascular (n=19; 25.7%) or hybrid (n=22; 29.7%). Causative organisms were identified in 56 patients (75.7%). At presentation, 26 patients (35.1%) required salvage surgery, open (n=22; 29.7%) or endovascular (n=8; 10.8%), and 17 radiological drainage (23.0%). During follow-up, 8 required drainage and 11 (14.9%) graft removal (5 complete). Infectious complications included pseudoaneurysms (n=14; 18.9%), rupture (n=9; 12.2%), gastro-intestinal bleeding (n=13; 17.6%), septic embolisms (n=4; 5.4%), and thrombosis (n=12; 16.2%). In-hospital mortality was 20.3% (n=15), freedom from aortic-related death and overall survival was 77.1% (95%CI:65.2-85.3) and 70.4% (95%CI:58.3-79.7) at 1 year, and 61.7% (95%CI:46.1-74.0) and 43.1% (95%CI:29.2-56.3) at 5 years. Sepsis recurrence occurred in 37 patients (50.0%). Seven (16.3%) developed acquired antimicrobial resistance. Malnutrition (HR=3.3, 95%CI=1.4-7.6, p=.005), hemorrhagic shock at presentation (HR=2/9, 95%CI=1.0-8.2, p=.048), aorto-enteric fistulae (HR=3.3, 95%CI=1.3-8.4, p=.011), fungal coinfection (HR=3.5, 95%CI=1.2-11.5, p=.030) and infection with resistant micro-organisms (HR=3.1, 95%CI=1.1-8.3, p=.023) were significantly associated with worse survival without sepsis.
In-hospital and aortic-related mortality were significant but with salvage surgery and antibiotic therapy the median survival was 3 years. Sepsis recurrence remained frequent and further procedures were needed. These outcomes should be considered when graft excision is proposed. Known predictors of adverse outcomes should become important points for discussion in multidisciplinary team meetings.
Median survival was approximately 3 years with a 28.4% rate of salvage surgery in this bicentric retrospective observational study of 74 patients with aortic vascular graft and endograft infections who were initially turned down for complete graft removal. Malnutrition, hemorrhagic shock, aorto-enteric fistulae, fungal coinfection, and infection with resistant micro-organisms were significantly associated with worse survival without sepsis and should become important points for discussion to help decide management strategies during multidisciplinary team meetings.
In situ reconstruction (ISR) with autologous veins is the preferred method in infectious native aortic aneurysms (INAAs) or vascular (endo)graft infection (VGEI). However, access to biological ...substitutes can prove difficult and lacks versatility. This study evaluates survival and freedom from reinfection after ISR of INAA/VGEI using the antimicrobial Intergard Synergy graft combining silver and triclosan.
From February 2014 to April 2020, 86 antimicrobial grafts were implanted for aortic infection. The diagnosis of INAA/VGEI and reinfection was established based on the Management of Aortic Graft Infection Collaboration criteria. Survival was analyzed using the Kaplan-Meier method and log-rank P values.
The antimicrobial graft was implanted in 32 cases of INAA, 28 of VGI, and 26 of VEI. The median age was 69.0 (interquartile range: 62.0; 74.0), with a history of coronary artery disease (n = 21; 24.4%), chronic kidney disease (n = 11; 12.8%), cancer (n = 21; 24.4%), and immunosuppression (n = 27; 31.4%). Imaging showed infiltration (n = 14; 16.3%), air (n = 10; 11.6%), and rupture (n = 16; 18.6% including 22 aortoenteric fistulae AEnF). Symptoms included fever (n = 37; 43.0%), shock (n = 11; 12.8%), and pain (n = 47; 54.7%). Repair was undertaken through a midline laparotomy in 75 cases (87.2%) and coeliac cross-clamping in 19 (22.1%), suprarenal in 26 (30.2%), plus celiac trunk (n = 3), mesenteric (n = 5), renal (n = 13), or hypogastric (n = 4) artery reconstruction, and omental flap coverage (n = 41; 48.8%). For AEnF, the gastrointestinal tract was repaired using direct suture (n = 14; 16.3%) or resection anastomosis (n = 8; 9.3%). Causative organisms were identified in 74 patients (86.0%), with polymicrobial infection in 32 (37.2%) and fungal coinfection in 7 (8.1%). Thirty-day and in-hospital mortality were 14.0% and 22.1% (n = 12 and 19, respectively, 3 INAA 9.4%, 7 VGI 25.0%, and 9 VEI 34.6%). Seventy patients (81.4%) had a postoperative complication, 44 (51.2%) of whom returned to the operative room. The 1- and 2-year survival rates were 74.0% (95% confidence interval CI: 63.3-82.1) and 69.8% (95% CI: 58.5-78.5), respectively. Survival was significantly better for INAA vs VGEI (P = .01) and worse for AEnF (P = .001). Freedom from reinfection was 97.2% (95% CI: 89.2-99.3) and 95.0% (95% CI: 84.8-98.4) with six reinfections (7.0%) requiring two radiological/six surgical drainage and two graft removals. Primary patency was 88.0% (95% CI: 78.1-93.6) and 79.9% (95% CI: 67.3-88.1) with no significant difference between INAA and VGEI (P = .16).
ISR of INAA or VGEI with the antimicrobial graft showed encouraging early mortality, comparable to the rates found in femoral vein (9%-16%) and arterial allograft (8%-28%) studies, as well as mid-term reinfection. The highest in-hospital mortality was noted for VEI including nearly 50% of AEnF.
Endoleaks represent one of the main complications after endovascular aortic repair (EVAR) and can lead to increased re-intervention rates and secondary rupture. Serial lifelong surveillance is ...required and traditionally involves cross-sectional imaging with manual axial measurements. Artificial intelligence (AI)-based imaging analysis has been developed and may provide a more precise and faster assessment. This study aims to evaluate the ability of an AI-based software to assess post-EVAR morphological changes over time, detect endoleaks, and associate them with EVAR-related adverse events.
Patients who underwent EVAR at a tertiary hospital from January 2017 to March 2020 with at least 2 follow-up computed tomography angiography (CTA) were analyzed using PRAEVAorta 2 (Nurea). The software was compared to the ground truth provided by human experts using Sensitivity (Se), Specificity (Sp), Negative Predictive Value (NPV), and Positive Predictive Value (PPV). Endovascular aortic repair-related adverse events were defined as aneurysm-related death, rupture, endoleak, limb occlusion, and EVAR-related re-interventions.
Fifty-six patients were included with a median imaging follow-up of 27 months (interquartile range IQR: 20-40). There were no significant differences overtime in the evolution of maximum aneurysm diameters (55.62 mm IQR: 52.33-59.25 vs 54.34 mm IQR: 46.13-59.47; p=0.2162) or volumes (130.4 cm
IQR: 113.8-171.7 vs 125.4 cm
IQR: 96.3-169.1; p=0.1131) despite a -13.47% decrease in the volume of thrombus (p=0.0216). PRAEVAorta achieved a Se of 89.47% (95% confidence interval CI: 80.58 to 94.57), a Sp of 91.25% (95% CI: 83.02 to 95.70), a PPV of 90.67% (95% CI: 81.97 to 95.41), and an NPV of 90.12% (95% CI: 81.70 to 94.91) in detecting endoleaks. Endovascular aortic repair-related adverse events were associated with global volume modifications with an area under the curve (AUC) of 0.7806 vs 0.7277 for maximum diameter. The same trend was observed for endoleaks (AUC of 0.7086 vs 0.6711).
The AI-based software PRAEVAorta enabled a detailed anatomic characterization of aortic remodeling post-EVAR and showed its potential interest for automatic detection of endoleaks during follow-up. The association of aortic aneurysmal volume with EVAR-related adverse events and endoleaks was more robust compared with maximum diameter.
The integration of PRAEVAorta AI software into clinical practice promises a transformative shift in post-EVAR surveillance. By offering precise and rapid detection of endoleaks and comprehensive anatomic assessments, clinicians can expect enhanced diagnostic accuracy and streamlined patient management. This innovation reduces reliance on manual measurements, potentially reducing interpretation errors and shortening evaluation times. Ultimately, PRAEVAorta's capabilities hold the potential to optimize patient care, leading to more timely interventions and improved outcomes in endovascular aortic repair.
The increasing use of endovascular aneurysm repair (EVAR) appears to be associated with the burden of vascular endograft infections. Complete stent graft explantation is recommended but leads to ...significant mortality. This study aimed to assess the technical challenges, complications, and mortality rate following infected endograft explantation.
Patients who underwent abdominal aortic endograft explantation for infection at the Bordeaux University Hospital from July 2008 to December 2020 were included retrospectively in this single centre observational study. The diagnosis was established based on the MAGIC criteria. The primary endpoint was 30 day mortality. Secondary endpoints were 90 day and in hospital mortality, survival, and re-infection.
Thirty-four patients were included, median age 69 years (interquartile range IQR 65, 76), with four (12%) treated as an emergency. The median time from EVAR to explantation was 17.5 months (4.5 – 36.3). In situ reconstruction was carried out with prosthetic grafts in 24 patients (71%, including 23 antimicrobial grafts combining silver and triclosan), and biological grafts in 10 (five femoral veins, four arterial allografts, three bovine patches, one biosynthetic graft). Seventeen aorto-enteric fistulae (AEnF) were addressed with direct repair of the intestinal tract (n = 10/17; 59%) or resection and anastomosis (n = 7/17; 41%). The culture was polymicrobial in 12 patients (35%) and remained sterile in four (12%). The 30 day and in hospital mortality rates were 21% (n = 7) and 27% (n = 9). Twenty-five patients (73%) presented with early post-operative complications, requiring 16 revision procedures (47%). Over a median follow up of 16.2 months (IQR 8.3, 33.6), the mortality rate was 35% (n = 12; 11 aortic related; 32%), with two re-infections (6%), both after biological reconstruction (one for an AEnF).
Early morbidity and mortality remain high after complete infected endograft explantation, even in a high volume centre. Comparison with other treatment modalities in large multicentre cohorts might be of interest.
Endovascular aortic repair (EVAR) surveillance relies on serial measurements of the maximal diameter despite significant inter- and intraobserver variability. Volumetric measurements are more ...sensitive; however, their general use has been hampered by the time required for their implementation. An innovative, fully automated software (PRAEVAorta; Nurea, Bordeaux, France), using artificial intelligence, had previously demonstrated fast and robust detection of the characteristics of infrarenal abdominal aortic aneurysms on preoperative imaging studies. In the present study, we assessed the robustness of these data on post-EVAR computed tomography (CT) scans.
We compared fully automatic and semiautomatic segmentation manually corrected by a senior surgeon (E.D.) using a dataset of 48 patients (48 early post-EVAR CT scans with 6466 slices and 101 follow-up CT scans with 13,708 slices).
The analyses confirmed the excellent correlation of the post-EVAR volumes and surfaces and the proximal neck and maximum aneurysm diameters measured using the fully automatic and manually corrected segmentation methods (Pearson’s coefficient correlation, >0.99; P < .0001). A comparison between the fully automatic and manually corrected segmentation methods revealed a mean Dice similarity coefficient of 0.950 ± 0.015, Jaccard index of 0.906 ± 0.028, sensitivity of 0.929 ± 0.028, specificity of 0.965 ± 0.016, volumetric similarity of 0.973 ± 0.018, and mean Hausdorff distance/slice of 8.7 ± 10.8 mm. The mean volumetric similarity reached 0.873 ± 0.100 for the lumen and 0.903 ± 0.091 for the thrombus. The segmentation time was nine times faster with the fully automatic method (2.5 minutes vs 22 minutes per patient with the manually corrected method; P < .0001). A preliminary analysis also demonstrated that a diameter increase of 2 mm can actually represent a >5% volume increase.
PRAEVAorta enabled a fast, reproducible, and fully automated analysis of post-EVAR abdominal aortic aneurysm sac and neck characteristics, with a comparison between different time points. It could become a crucial adjunct for EVAR follow-up through the early detection of sac evolution, which might reduce the risk of secondary rupture.
This paper presents an approach exploiting the sensitivity of Lamb waves for characterizing the viscoelastic moduli and thickness of plates. The analytical sensitivity functions are first derived in ...the case of an isotropic plate and are integrated into an iterative inverse problem to optimize its viscoelastic moduli and thickness based on a zero-finding approach (Gauss–Newton algorithm for a multivariable problem). This method is validated numerically for a viscoelastic plate and shows high accuracy and low computational cost when compared to existing methods. Experimental validation demonstrates the ability of the algorithm to assess simultaneously the viscoelastic moduli and the thickness of isotropic plate-like structures.
PDF
