Contemporary Results with the Biosynthetic Glutaraldehyde Denatured Ovine Collagen Graft (Omniflow II) in Lower Extremity Arterial Revascularization in a Septic Context.

BACKGROUND: Peripheral vascular graft infections are poorly-evaluated, despite high mortality and amputation rates. The vascular substitute of choice remains controversial when veins are unavailable. This study aims to evaluate the results of a biosynthetic collagen graft (Omniflow II®) in an infected field when autologous veins are unavailable. METHODS: This retrospective, multicentric study included all consecutive patients in whom an Omniflow II graft was used for infra-inguinal revascularization in a septic context from January 2015 to January 2020. The primary end-point was freedom from major amputation; secondary end-points were 30-day mortality, survival, patency, and freedom from reinfection estimated using the Kaplan-Meier method. RESULTS: Twenty-nine patients (27 men, median age of 69 years interquartile range IQR:60; 76) were included. Fever was present in 58.6%, a septic rupture in 17.9%, a pseudo-aneurysm in 25.0%. The 30-day mortality rate was 3.4%. Median follow-up reached 49 months. At 1 and 3 years, estimated freedom from major amputation was 88.4% and 83.9%, survival: 96%, primary patency: 74.6% and 65.8%, and reinfection free-survival: 85.6%. There were 7 occlusions (1 iliofemoral, 1 below-knee, and 5 above-knee bypasses), 3 explantations for persistent sepsis, 4 reinfections (all within 6 months which led to 1 death and 3 out of 4 major amputations). The risk of major amputation increased with bypass reinfection (P = 0.004), occlusion (P = 0.005), and polymicrobial infection (P = 0.05). CONCLUSIONS: In a septic context, the Omniflow II graft shows acceptable freedom from major amputation and reinfection. This usage remains outside the instructions of use, it is, therefore, is essential to pursue longer-term studies in larger cohorts.

Outcomes of biosynthetic vascular graft for infrainguinal femoro-popliteal and femoro-distal revascularization.

BACKGROUND: The aim of this study was to retrospectively analyze early and late outcomes of infrainguinal revascularization performed with the Omniflow-II® (LeMaitre Vascular, Inc., Burlington, MA, USA) biosynthetic vascular graft (BVG) for complex femoro-popliteal obstructive disease. METHODS: Over a 10-year period, this BVG was used in 110 patients who underwent infrainguinal femoro-popliteal or femoro-distal bypass. Early (intraoperative and <30 days) results were analyzed in terms of death, thrombosis, amputations and reinterventions. Follow-up results were analyzed in terms of primary and secondary graft patency, and amputation-free survival. RESULTS: We performed 87 (79.1%) above-the-knee bypass, 20 (18.2%) below-the-knee bypass, and 3 (2.7%) tibial artery bypass. In-hospital mortality was not observed. Mean follow-up was 66±37 months (range, 3-150). Estimated primary patency rate at 1, 2 and 5-years of follow-up was 77%±4 (95%CI: 68-84), 73%±5 (95%CI: 63.5-83), and 59%±6 (95%CI: 47-70.5) respectively. Predictors of primary patency loss were the presence of critical limb ischemia (P=0.048; HR: 2.1; 95%CI: 1.01-4.28), and the necessity of below-the-knee bypass (P=0.012; HR: 2.4; 95%CI: 1.22-4.75). Aneurysmal degeneration of the BVG was detected in 4 (3.6%) patients, an infected BVG occurred in 3 (2.7%) patients. The amputation-free survival was 96%±2 (95%CI: 91-99), 93%±3 (95%CI: 86-96), and 76%±5 (95%CI: 66-84) at 1, 2 and 5-years respectively. CONCLUSIONS: In our experience, Omniflow-II® is a valid first-line alternative for infrainguinal revascularization when the ipsilateral autologous saphenous vein is not available. Aneurysmal degeneration was lower than previously reported with alternative BVGs, and the incidence of BVG infection was acceptably low.

Fully automatic volume segmentation of infrarenal abdominal aortic aneurysm computed tomography images with deep learning approaches versus physician controlled manual segmentation.

OBJECTIVE: Imaging software has become critical tools in the diagnosis and decision making for the treatment of abdominal aortic aneurysms (AAA). However, the interobserver reproducibility of the maximum cross-section diameter is poor. This study aimed to present and assess the quality of a new fully automated software (PRAEVAorta) that enables fast and robust detection of the aortic lumen and the infrarenal AAA characteristics including the presence of thrombus. METHODS: To evaluate the segmentation obtained with this new software, we performed a quantitative comparison with the results obtained from a semiautomatic segmentation manually corrected by a senior and a junior surgeon on a dataset of 100 preoperative computed tomography angiographies from patients with infrarenal AAAs (13,465 slices). The Dice similarity coefficient (DSC), Jaccard index, sensitivity, specificity, volumetric similarity (VS), Hausdorff distance, maximum aortic transverse diameter, and the duration of segmentation were calculated between the two methods and, for the semiautomatic software, also between the two observers. RESULTS: The analyses demonstrated an excellent correlation of the volumes, surfaces, and diameters measured with the fully automatic and manually corrected segmentation methods, with a Pearson's coefficient correlation of greater than 0.90 (P < .0001). Overall, a comparison between the fully automatic and manually corrected segmentation method by the senior surgeon revealed a mean Dice similarity coefficient of 0.95 ± 0.01, a Jaccard index of 0.91 ± 0.02, sensitivity of 0.94 ± 0.02, specificity of 0.97 ± 0.01, VS of 0.98 ± 0.01, and mean Hausdorff distance per slice of 4.61 ± 7.26 mm. The mean VS reached 0.95 ± 0.04 for the lumen and 0.91 ± 0.07 for the thrombus. For the fully automatic method, the segmentation time varied from 27 seconds to 4 minutes per patient vs 5 minutes to 80 minutes for the manually corrected methods (P < .0001). CONCLUSIONS: By enabling a fast and fully automated detailed analysis of the anatomic characteristics of infrarenal AAAs, this software could have strong applications in daily clinical practice and clinical research.

The role of emergency presentation and revascularization in aneurysms of the peripancreatic arteries secondary to celiac trunk or superior mesenteric artery occlusion.

OBJECTIVE: The goal of this study was to analyze our 10-year experience in the treatment of aneurysms of the collateral circulation secondary to steno-occlusions of the celiac trunk (CT) or superior mesenteric artery (SMA). METHODS: In the last 10 years, 32 celiac-mesenteric aneurysms were detected (25 true aneurysms and seven pseudoaneurysms) in 25 patients with steno-occlusion of the CT or SMA. All cases were diagnosed and treated at our center, with either surgical or endovascular approach. As open surgery, we performed aneurysmectomy and revascularization; as endovascular treatment we performed both the embolization (or graft exclusion) of the aneurysm sac, and embolization of afferent and efferent arteries. RESULTS: Sixteen patients (64%) underwent endovascular treatment, accounting for 66% of aneurysms (21/32). Six patients (24%) and seven associated aneurysms (22%) underwent open surgery. Three asymptomatic patients (12%), representing a total of four aneurysms (12%), were not treated. For endovascular procedures, the technical success rate was 90%, with a 56% clinical success rate. For open surgery, clinical and technical success were achieved in five patients (83%) and six procedures (86%), respectively. Sixty-eight percent of patients (17/25) were treated in an emergency setting, using either endovascular (88%) or open (12%) approaches. Although technical success was achieved in more than 85% of these procedures for both approaches, clinical success was reached less frequently among patients with an acute presentation (P = .041). Regardless of the type of treatment, CT or SMA revascularization during the first procedure did not show an increased rate of clinical success (P = .531). However, we reported four cases of visceral ischemia after an endovascular approach without revascularization, with three open surgical corrections required. The mean follow-up was 41 months (range, 0-136 months). CONCLUSIONS: Neither of the approaches described qualifies as a standard optimal choice. We suggest a tailored therapeutic approach based on the clinical condition at the time of diagnosis and specific vascular anatomy.

Impact of the Bird-Beak Configuration on Postoperative Outcome After Thoracic Endovascular Aortic Repair: A Meta-analysis.

Purpose: To investigate the association between the bird-beak configuration (BBC), a wedge-shaped gap between the undersurface of a thoracic endograft and the lesser curvature of the arch after thoracic endovascular aortic repair (TEVAR), and postoperative outcome after TEVAR. Methods: The study was performed according to the PRISMA guidelines. The PubMed, EMBASE, and Cochrane databases were searched to identify all case series reporting BBC after TEVAR between 2006 and April 2018. Data analysis was performed considering the difference in the risk of complications for presence vs absence of BBC. After screening 1633 articles, 21 studies were identified that matched the selection criteria; 12 of these reported detailed information to investigate the postoperative outcome using proportion meta-analysis with a random effects model. The pooled risk difference is reported with the 95% confidence interval (CI). Heterogeneity of the included studies was assessed with the I2 statistic (low 25%, medium 50%, high 75%). Results: Complications occurred within a range of 0 to 72 months in 14.7% (95% CI 7.4% to 27.3%) of patients with BBC and in 6.3% (95% CI 2.5% to 15.4%) of patients without BBC. A cumulative incidence could not be assessed. The summary risk difference was 11.1% (95% CI -0.1% to 22.3%, p=0.052). There was significant heterogeneity (I2=85.6%). The Egger test did not show evidence of publication bias (p=0.975). When specifically considering type Ia endoleak and endograft migration, the risk difference between BBC and non-BBC patients was 8.2% (95% CI 0.3% to 16.1%, p=0.042; I2=69.0%). The specific risk difference for endograft collapse/infolding and thrombosis was 3.7% (95% CI -3.5% to 11.1%, p=0.308; I2=10.2%). Conclusion: At present the literature does not provide statistical evidence to establish an overall prognostic value of the BBC. Nevertheless, the BBC appears to be associated with a high risk of type Ia endoleak and endograft migration, which warrants specific and long-term surveillance. Clinically relevant values for BBC grading should be established to perhaps define indications for preemptive treatment based on the presence of BBC only.

Concomitant Renal Artery and Aortic Aneurysm: Is Endovascular Surgery the Correct Approach?

Our case illustrates the concomitant presence of a giant aneurysm of the left renal artery at the ostium and an abdominal aortic aneurysm, in presence of a complex aortic anatomy. Type of approach and timing of the treatment is still not well established for the rare coexistence of these 2 pathologies. In case of surgical high-risk patients, endovascular therapy is considered now the best choice to exclude arterial and aortic aneurysms although there are chances to do further interventions in the follow-up. For this reason, we simultaneously treated both the aneurysms through an embolization with plugs and coils of renal aneurysm and endovascular exclusion of aortic aneurysm; in the follow-up, renal function of the patient worsened until hemodialysis and we saw the reperfusion of renal aneurysm and the onset of endoleak I type A from above the aortic and renal aneurysm and B from iliac legs of the previous endograft. We performed a parallel graft technique on visceral vessels to exclude the refilling of both aneurysms and preserve visceral vascularization. Follow-up at 12 months showed the complete exclusion of the aneurysms and the patency of stents in celiac trunk and superior mesenteric artery.