Systematic Review and Meta-Analysis of the Effect of Anticoagulation on Outcomes After Endovascular Aneurysm Repair.

PURPOSE: Our objective was to investigate whether patients who receive anticoagulation therapy have different outcomes after endovascular aneurysm repair (EVAR) from those who do not. MATERIALS AND METHODS: We conducted a systematic review of studies that compared outcomes of EVAR in patients who were on therapeutic anticoagulation vs those who were not. We developed and reported the review in accordance with the PRISMA guidelines with a registered protocol (CRD42022375894). The Ovid interface was used to search Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica Database (EMBASE), and Cochrane Central Register of Controlled Trials (CENTRAL) up to November 2022. The quality of studies was assessed with the Newcastle-Ottawa Scale (NOS) (maximum score=9), and the evidence was appraised with the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. The hazard ratio (HR) and 95% confidence interval (CI) was the effect estimate in time-to-event meta-analyses, calculated using the inverse-variance statistical method and random-effects models. RESULTS: Sixteen studies qualified for inclusion reporting a total of 35 739 individuals. Anticoagulated patients had a statistically significantly higher hazard of death (HR=1.93, 95% CI=1.03-3.63), endoleak (HR=2.13, 95% CI=1.55-2.93), reintervention (HR=1.79, 95% CI=1.27-2.52), and aneurysm sac expansion (HR=2.72, 95% CI=1.57-4.72) than patients not receiving anticoagulation therapy. The median score on the NOS was 7 (range=4-9). The certainty of evidence was very low for mortality and reintervention and low for endoleak and sac expansion. CONCLUSIONS: Anticoagulation is a poor prognostic factor after standard EVAR and should be considered in decision-making, consent processes, and surveillance strategies. CLINICAL IMPACT: The number of individuals who take anticoagulation treatment has been rapidly increasing over the recent years. We aimed to investigate the effect of such treatment on outcomes after endovascular aneurysm repair (EVAR). Anticoagulated patients were found to have increased mortality, endoleak, and reintervention rates after EVAR compared to their non-anticoagulated counterparts. Anticoagulation therapy has a prognostic role in EVAR and should be considered in decision making and EVAR surveillance. Anticoagulated patients need to be informed of the higher failure rates of EVAR, and intensified surveillance strategies may need to be implemented in this patient cohort.

Systematic Review With Meta-Analysis of Endovascular Versus Open Repair of Abdominal Aortic Aneurysm Repair in the Young.

PURPOSE: The purpose of this study was to investigate which treatment method for abdominal aortic aneurysm (AAA), endovascular or open repair, has better outcomes in young patients. MATERIALS AND METHODS: A systematic review was conducted to identify observational studies or randomized controlled trials (RCTs) that compared endovascular and open repair of intact AAA in young patients. MEDLINE, EMBASE, and CENTRAL were searched up to March 2022 using the Ovid interface. The risk of bias was assessed with the Newcastle-Ottawa scale (NOS), with a maximum score of 9, or version 2 of the Cochrane risk of bias tool. The certainty of evidence was assessed with the GRADE framework. Primary outcomes were perioperative, overall, and aneurysm-related mortality. Secondary outcomes were reintervention, hospital length of stay, and perioperative complications. Effect measures in syntheses were the odds ratio (OR), risk difference (RD), mean difference (MD), or hazard ratio (HR) and were calculated with the Mantel-Haenszel or inverse variance statistical method and random-effects models. RESULTS: Fifteen observational studies and 1 RCT were included, reporting a total of 48 976 young patients. Definitions of young ranged from 60 to 70 years. The median score on the NOS was 8 (range: 4-9), and the RCT was judged to be high risk of bias. The perioperative mortality was lower after EVAR (RD: -0.01, 95% CI: -0.02 to -0.00), but the overall and aneurysm-related mortality was not significantly different between EVAR and open repair (HR: 1.38, 95% CI: 0.81 to 2.33; HR: 4.68, 95% CI: 0.71 to 31.04, respectively), as was the hazard of reintervention (HR: 1.50, 95% CI: 0.88 to 2.56). The hospital length of stay was shorter after EVAR (MD: -4.44 days, 95% CI: -4.79 to -4.09), and the odds of cardiac (OR: 0.22, 95% CI: 0.13 to 0.35), respiratory (OR: 0.17, 95% CI: 0.11 to 0.26), and bleeding complications were lower after EVAR (OR: 0.26, 95% CI: 0.11 to 0.64). The level of evidence was low or very low. CONCLUSION: Patient preferences and perspectives should be considered during shared decision-making process considering the available evidence. EVAR may be considered in young and fit patients with a suitable anatomy. PROTOCOL REGISTRATION: PROSPERO, CRD42022325051. CLINICAL IMPACT: Uncertainty surrounds the optimal treatment strategy for abdominal aortic aneurysm in young patients. Meta-analysis of some 48,976 young patients showed that endovascular aneurysm repair (EVAR) has a lower perioperative mortality and morbidity and a shorter hospital and intensive care unit stay than open surgical repair, but the overall and aneurysm-related mortality in the short to medium term are not significantly different between EVAR and open repair. EVAR can be considered in young patients.

Pre-Emptive Embolization of the Aneurysm Sac or Aortic Side Branches in Endovascular Aneurysm Repair: Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials.

BACKGROUND: To investigate outcomes of pre-emptive embolization of the aneurysm sac or aortic side branches in endovascular aneurysm repair (EVAR). METHODS: The review was reported as per Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 with a preregistered protocol. Bibliographic sources (MEDLINE, Embase, and CENTRAL) were searched using subject headings and free text terms. Randomized controlled trials comparing EVAR with versus without embolization were included. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) or risk difference (RD) and 95% confidence interval (CI) applying the Mantel-Haenszel method. Continuous outcomes were summarized using mean difference (MD) and 95% CI applying the inverse variance method. The certainty of evidence was appraised with the Grading of Recommendations Assessment, Development, and Evaluation framework. Version 2 of the Cochrane tool was used to assess the risk of bias. Trial sequential analysis assumed alpha = 5% and power = 80%. RESULTS: Four randomized controlled trials were included. No significant difference was found in aneurysm-related mortality (RD 0.00, 95% CI -0.03 to 0.03), overall mortality (OR 1.85, 95% CI 0.42-8.13), aneurysm rupture (RD 0.00, 95% CI -0.03 to 0.03), type II endoleak-related reintervention (RD -0.07, 95% CI -0.21 to 0.06), procedure time (MD 20.12, 95% CI -11.54 to 51.77), or fluoroscopy time (MD 11.17, 95% CI -11.22 to 33.56). Patients with pre-emptive embolization had significantly lower odds of type II endoleak (OR 0.45, 95% CI 0.26-0.78) and sac expansion (OR 0.19, 95% CI 0.07-0.52). The risk of bias was high for all outcomes. The certainty of evidence was very low for all outcomes, except for type II endoleak, for which it was low. Trial sequential analysis showed an inconclusive result for overall mortality and type II endoleak-related reintervention but confirmed the advantage of embolization in reducing type II endoleak and sac expansion. CONCLUSIONS: Limited, low certainty data suggest pre-emptive embolization confers no clinical benefits in EVAR.

Late Neck Related Adverse Events are Rare Among Patients with Wide Aortic Neck Undergoing Endovascular Aneurysm Repair with the Ovation Endograft.

BACKGROUND: Patients with wide aortic necks undergoing Endovascular Aneurysm Repair (EVAR) have been shown to be at a higher risk for neck-related complications. We aim to examine outcomes of EVAR with an endograft exerting minimal outward pressure (Ovation-Endologix) in patients with a large baseline neck diameter. METHODS: We performed a retrospective single center study, including consecutive patients undergoing EVAR with the Ovation system from May 2011 to April 2021. Patients were divided in Groups 1 and 2 if the 20, 23, 26, 29 mm or the 34 mm proximal diameter main body was used, respectively. According to the instructions for use of the device, for neck diameters 27-30 mm the 34 mm main body is required. Primary endpoint was rate of neck related complications during follow-up, (type Ia endoleak, migration >10 mm and neck-related re-interventions) and rate of aortic neck dilatation (AND). AND was determined based on multiple aortic neck diameters that were recorded and compared between the 1-month computed tomography angiography (CTA) after EVAR and the last available follow-up CTA.Secondary endpoints were peri-procedural and follow-up outcomes such as endoleaks, reinterventions and overall mortality. RESULTS: In total 281 patients were included, 222 in Group 1 and 59 in Group 2. Patients in Group 2 presented significantly shorter neck length, higher neck angulation and more common reversed tapered configuration. Median follow-up was 36 months (Range: 6-106). Early and late type Ia endoleak was observed in 4 and 2 patients in each group, respectively (P = 0.063 and P = 0.195, respectively). Distal migration was observed in 2 patients in Group 2 and AND was recorded in 2 patients in each group (P = 0.195). Freedom from the primary endpoint was estimated at 98%, 94%, 94% at 12-, 36-, 60-months for Group 1 and at 98%, 95%, 86% for Group 2 (P-Value 0.266). Probability of survival was 95%, 86%, 75% at 12-, 36-, 60-months for Group 1 and 83%, 77%, 72% for Group 2 (P-Value 0.226).Multivariate regression analysis identified neither Group 1 versus Group 2 nor absolute value of aortic neck diameter as significant predictors of neck-related adverse events. Neck diameters did not display significant differences over time in any of the levels evaluated. CONCLUSIONS: EVAR with the Ovation endograft results in low rates of late neck related complications which is also true for patients with wide baseline aortic necks.

Dual-Energy Computed Tomography as an Adjunct in the Evaluation of Peripheral Chronic Total Occlusions: A Feasibility Study.

This study investigated the role of dual-energy computed tomography (CT) for lesion characterization in patients with peripheral arterial disease manifesting with chronic total occlusions (CTOs). Forty-one symptomatic patients with CTOs underwent dual-energy CT angiography before endovascular treatment. The lesions were subsequently analyzed in a dedicated workstation, and 2 indexes-dual-energy index (DEI) and effective Z (Zeff)-were calculated, ranging from 0.0027 to 0.321 and from 6.89 to 13.02, respectively. Statistical analysis showed a significant correlation between the DEI and Zeff values (P < .001). The interobserver intraclass correlation coefficient was 0.91 for the mean Zeff values and 0.86 for the mean DEI values. This technique could potentially provide useful information regarding the composition of a CTO.

Editor's Choice - Endovascular Aneurysm Repair in High Risk Patients: A Systematic Review and Meta-Analysis.

OBJECTIVE: To investigate outcomes of endovascular aneurysm repair (EVAR) in high risk patients. METHODS: Bibliographic sources (MEDLINE, EMBASE, CINAHL, and CENTRAL) were searched using combinations of thesaurus and free text terms. The review protocol was registered in PROSPERO (CRD42021287207) and reported according to PRISMA 2020. Pooled estimates were calculated using odds ratio (OR) or hazard ratio (HR) and 95% confidence interval (CI) applying the Mantel-Haenszel or inverse variance method. EVAR peri-operative mortality in high risk patients over time was examined with mixed effects meta-regression. The GRADE framework was used to rate the certainty of evidence. RESULTS: The pooled peri-operative mortality in 18 416 high risk patients who underwent EVAR was 3% (95% CI 2.3 - 4%) and has significantly reduced over time (year of publication p = .003; median study point p = .023). The peri-operative mortality was significantly lower in high risk patients treated with EVAR compared with open repair (OR 0.64; 95% CI 0.45 - 0.92), but no significant difference was found in overall (HR 1.06; 95% CI 0.76 - 1.49) or aneurysm related mortality (HR 0.57; 95% CI 0.21 - 1.55). No significant difference was found in overall mortality between high risk patients treated with EVAR vs. no intervention (HR 0.42; 95% CI 0.14 - 1.26), but the aneurysm related mortality was significantly lower in the former (HR 0.30; 95% CI 0.14 - 0.63). The peri-operative mortality was higher in high risk than normal risk patients treated with EVAR (OR 2.33; 95% CI 1.75 - 3.10), as was the overall mortality (HR 3.50; 95% CI 2.55 - 4.80). The certainty of evidence was very low for EVAR vs. open surgery or no intervention and low for high vs. normal risk patients. CONCLUSION: The EVAR peri-operative mortality in high risk patients has improved over time. Even though the aneurysm related mortality of EVAR is lower compared with no intervention, EVAR may confer no overall survival benefit.

Meta-Analysis of the Crossed Versus Standard Limb Configuration in Endovascular Aneurysm Repair.

OBJECTIVE: To investigate whether the crossed-limb technique confers better or worse clinical outcomes compared to the standard straight limb configuration in standard endovascular aneurysm repair (EVAR). METHODS: We conducted a systematic review to identify studies comparing outcomes of EVAR with the crossed versus standard limb configuration. MEDLINE, EMBASE, CINAHL, and CENTRAL were searched in March 2021 using the Healthcare Databases Advanced Search interface developed by the National Institute for Heath and Care Excellence. The risk of bias was assessed with the Newcastle-Ottawa scale (NOS) and the Risk Of Bias In Non-randomized Studies - of Interventions (ROBINS-I) tool. Summary estimates were calculated using the odds ratio (OR), risk difference (RD), or mean difference (MD) and 95% confidence interval (CI), applying the Mantel-Haenszel or inverse variance statistical method. Random-effects models were employed. RESULTS: Four observational studies qualified for inclusion, reporting a total of 1132 patients. All presented contemporary experiences. Baseline clinical characteristics were largely similar between patients with and without the crossed-limb configuration, but the anatomy tended to be less favourable in patients treated with the crossed-limb technique. No statistically significant difference was found in the primary outcomes: limb occlusion (OR 1.44, 95% CI 0.65 - 3.19), type Ib endoleak (RD 0.01, 95% CI -0.03 - 0.04), type III endoleak (RD 0.01, 95% CI -0.01 - 0.03); or secondary outcomes: perioperative mortality (RD 0.00, 95% CI -0.03 - 0.03), type Ia endoleak (RD 0.00, 95% CI -0.03 - 0.02), type II endoleak (OR 1.38, 95% CI 0.51 - 3.74), procedure duration (MD 18.07 min, 95% CI -1.14-37.29). Inconsistency across studies was low for all outcomes. The studies were judged to be of high quality on the NOS. The main bias identified using the ROBINS-I tool was due to confounding. CONCLUSIONS: The crossed-limb technique was not found to confer inferior clinical outcomes in the medium term compared to the standard limb configuration in patients who undergo standard EVAR.

Time-to-event data meta-analysis of late outcomes of endovascular versus open repair for ruptured abdominal aortic aneurysms.

OBJECTIVE: We investigated whether the well-documented perioperative survival advantage of emergency endovascular aneurysm repair (EVAR) compared with open repair would be sustained during follow-up. METHODS: A systematic review conforming to the PRISMA (preferred reporting items for systematic reviews and meta-analyses) statement standards was conducted to identify studies that had reported the follow-up outcomes of endovascular vs open repair for ruptured abdominal aortic aneurysms. Electronic bibliographic sources (MEDLINE [medical literature analysis and retrieval system online], Embase [Excerpta Medica database], CINAHL [cumulative index to nursing and allied health literature], and CENTRAL [Cochrane central register of controlled trials]) were interrogated using the Healthcare Databases Advanced Search interface (National Institute for Health and Care Excellence, London, United Kingdom). A time-to-event data meta-analysis was performed using the inverse variance method, and the results were reported as summary hazard ratios (HRs) and associated 95% confidence intervals (CIs). Mixed effects regression was applied to investigate the outcome changes over time. The quality of the body of evidence was appraised using the GRADE (grades of recommendation, assessment, development, and evaluation) system. RESULTS: Three randomized controlled trials and 22 observational studies reporting a total of 31,383 patients were included in the quantitative synthesis. The mean follow-up duration across the studies ranged from 232 days to 4.9 years. The overall all-cause mortality was significantly lower after EVAR than after open repair (HR, 0.79; 95% CI, 0.73-0.86). However, the postdischarge all-cause mortality was not significantly different (HR, 1.10; 95% CI, 0.85-1.43). The aneurysm-related mortality, which was reported by one randomized controlled trial, was not significantly different between EVAR and open repair (HR, 0.89; 95% CI, 0.69-1.15). Meta-regression showed the mortality difference in favor of EVAR was more pronounced in more recent studies (P = .069) and recently treated patients (P = .062). The certainty for the body of evidence for overall and postdischarge all-cause mortality was judged to be low and that for aneurysm-related mortality to be high. CONCLUSIONS: EVAR showed a sustained mortality benefit during follow-up compared with open repair. A wider adoption of an endovascular-first strategy is justified.

Discrimination of High-Risk Type-2 Endoleak after Endovascular Aneurysm Repair through CT Perfusion: A Feasibility Study.

A type-2 endoleak after an endovascular aneurysm repair is the most prevalent type of endoleak, but as the clinical consequence of its diagnosis is uncertain, at present, management decisions are solely based on aneurysm sac growth. The aim of this study was to investigate the potential of various computed tomography perfusion parameters for their ability to distinguish high-risk type-2 endoleaks from low-risk type-2 endoleaks after an endovascular aneurysm repair.

Editor's Choice - Systematic Review and Meta-Analysis of the Impact of Institutional and Surgeon Procedure Volume on Outcomes After Ruptured Abdominal Aortic Aneurysm Repair.

OBJECTIVE: To investigate whether there is a correlation between institutional or surgeon case volume and outcomes in patients with ruptured abdominal aortic aneurysm (rAAA). DATA SOURCES: The Healthcare Database Advanced Search interface developed by the National Institute of Health and Care Excellence was used to search MEDLINE, Embase, CINAHL, and CENTRAL. REVIEW METHODS: The systematic review complied with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines with the protocol registered in PROSPERO (CRD42020213121). Prognostic studies were considered comparing outcomes of patients with rAAA undergoing repair in high and low volume institutions or by high and low volume surgeons. Pooled estimates for peri-operative mortality were calculated using the odds ratio (OR) and 95% confidence intervals (CI), applying the Mantel-Haenszel method. Analysis of adjusted outcome estimates was performed with the generic inverse variance method. RESULTS: Thirteen studies reporting a total of 120 116 patients were included. Patients treated in low volume centres had a statistically significantly higher peri-operative mortality than those treated in high volume centres (OR 1.39; 95% CI 1.22 - 1.59). Subgroup analysis showed a mortality difference in favour of high volume centres for both endovascular aneurysm repair (EVAR; OR 1.61, 95% CI 1.11 - 2.35) and open repair (OR 1.50, 95% CI 1.25 - 1.81). Adjusted analysis showed a benefit of treatment in high volume centres for open repair (OR 1.68, 95% CI 1.21 - 2.33) but not for EVAR (OR 1.42, 95% CI 0.84 - 2.41). Differences in peri-operative mortality between low and high volume surgeons were not statistically significant for either EVAR (OR 1.06, 95% CI 0.59 - 1.89) or open surgical repair (OR 1.18, 95% CI 0.87 - 1.63). CONCLUSION: A high institutional volume may result in a reduction of peri-operative mortality following surgery for rAAA. This peri-operative survival advantage is more pronounced for open surgery than EVAR. Individual surgeon caseload was not found to have a significant impact on outcomes.

The Use of a Suture Mediated Vascular Closure Device to Achieve Hemostasis following Arterial Access through Previously Implanted Synthetic Grafts.

BACKGROUND: Percutaneous endovascular aneurysm repair (EVAR) and peripheral interventions using the Perclose Proglide suture mediated system has not been adequately studied in patients with synthetic grafts at access sites. METHODS: We report the use of the Perclose Proglide in 10 patients in whom previously inserted synthetic grafts in the groin were punctured for arterial access (5 for peripheral interventions and 5 undergoing EVAR). In patients undergoing peripheral interventions a single device was used, while in patients undergoing EVAR 2 devices were employed per access site. The preclosing technique was used in every case. RESULTS: Hemostasis was achieved in all patients. No complications were observed except for a small laceration and a localized hemodynamically nonsignificant stenosis, without any clinical sequel. CONCLUSIONS: This small case series indicates the feasibility of percutaneous access with the Perclose Proglide system to perform EVAR and peripheral endovascular interventions in the presence of synthetic grafts in the groin, with promising outcomes.

Endovascular Aneurysm Repair with Bifurcated Stent Grafts in Patients with Narrow Versus Regular Aortic Bifurcation: Systematic Review and Meta-analysis of Comparative Studies.

BACKGROUND: Narrow aortic bifurcation (NAB) is considered as a risk factor for endograft limb thrombosis. The purpose of the study was to investigate the effect of narrow aortic bifurcation on outcomes of elective endovascular aneurysm repair (EVAR). METHODS: A systematic review that conformed to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed. We searched electronic bibliographic databases using a combination of controlled vocabulary (thesaurus) and free-text terms to identify relevant studies comparing outcomes of EVAR in patients with NAB versus those with regular aortic bifurcation. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) and those of continuous outcomes using mean difference and 95% confidence interval (CI). To account for expected heterogeneity, the random-effects model was applied for statistical analysis. RESULTS: Six observational studies were included, reporting a total of 2,673 patients (412 with NAR and 2,261 with friendly anatomy). Perioperative mortality was similar between the groups (OR 1.14, 95% CI 0.30-4.34, P = 0.85, I2 = 0%). Limb stenosis and kinking requiring additional intraoperative procedures was significantly more common among patients with NAB (OR 3.02, 95% CI 2.16-4.22, P < 0.00001, I2 = 0%). Nevertheless, 30-day reintervention rate was similar between the groups, as was the rate of limb occlusion during follow-up. CONCLUSIONS: Available evidence suggests that at the expense of significantly more intraoperative additional procedures, EVAR with bifurcated devices can be safely performed in patients with NAB.

The level of bifurcation of peroneal artery and its implications for posterolateral approach to the ankle: a CT angiography study.

PURPOSE: This study aims to provide data, with the use of computed tomography angiography, regarding the level of bifurcation of the peroneal artery to the anterior perforating branch and the lateral calcaneal branch, in relation to the osseous anatomic structures of the tibial plafond, the medial malleolus and the lateral malleolus. METHODS: The study included patients who underwent diagnostic computed tomography angiography of the lower extremities. Measurements were performed in two-dimensional reconstructions and included the perpendicular distance from peroneal artery bifurcation into anterior perforating branch and lateral calcaneal branch to the lowest level of tibial plafond (D1), medial malleolus (D2) and lateral malleolus (D3). The distances were also normalized to the length of the tibia. RESULTS: Sixty patients and a total of 115 limbs were enrolled in this study. The mean distance ± standard deviation from peroneal artery bifurcation to tibial plafond (D1) was 4.33 ± 1.12 cm (normalized 0.12 ± 0.03) (range 2.54-8.26 cm), to medial malleolus (D2) was 5.53 ± 1.18 cm (normalized 0.16 ± 0.03) (range 3.27-9.5 cm) and to lateral malleolus (D3) was 6.53 ± 1.17 cm (normalized 0.18 ± 0.03) (range 4.71-10.2 cm), respectively. There was no significant difference between right and left limb measurements (p > 0.05). Females presented lower, but not statistically significant (p > 0.05), D1, D2 and D3 measurements compared to males. CONCLUSION: The bifurcation of the peroneal artery takes place at lower level compared to previously published studies and consequently extreme caution should be exercised when performing the posterolateral approach to the ankle. This study adds to the understanding of the relevant vascular anatomy of the region and assists in performing the posterolateral approach to the ankle with safety.

Endovascular Treatment of Malignant Superior Vena Cava Syndrome through Upper-Limb Access: A Comparison between Venous-Dedicated and Conventional Stents.

PURPOSE: To retrospectively evaluate the technical and clinical outcomes of superior vena cava (SVC) stent placement through upper-limb venous access in malignant SVC syndrome (SVCS) and compare the efficacy of different nitinol stent types. MATERIALS AND METHODS: Between 2006 and 2018, 156 patients (132 male; mean age, 62 y; age range, 33-81 y) underwent SVC stent placement for malignant obstructions through upper-limb venous access with 1 of 3 types of nitinol stent: 1 venous-dedicated (Sinus-XL stent) and 2 non-venous-dedicated (E-Luminexx Vascular Stent and Protégé GPS). Cases of common femoral vein access or non-nitinol stents were excluded from further analysis. The mean duration of follow-up was 8 mo. RESULTS: Technical success was achieved in 99.3% of cases. One patient died during the procedure as a result of cardiac tamponade. Balloon predilation was performed in 10 patients and postdilation in 126. Mean procedural time was 34.4 min (range, 18-80 min). Overall survival rates were 92.3%, 57.3%, and 26.8%, and overall primary patency rates were 94.5%, 84.8% and 79.6%, at 1, 6, and 12 mo, respectively. There were no statistically significant differences in primary patency rates between venous- and non-venous-dedicated stents or among different Stanford SVCS grading groups (P > .05). CONCLUSIONS: SVC stent placement through an upper-limb approach is a safe, fast, and effective technique. There is no evident benefit of venous-dedicated vs non-venous-dedicated stents in the treatment of malignant SVCS.

Meta-Analysis and Meta-Regression Analysis of Outcomes of Endovascular and Open Repair for Ruptured Abdominal Aortic Aneurysm.

OBJECTIVE: The aim was to assess peri-operative mortality of endovascular aneurysm repair (EVAR) vs. open repair for ruptured abdominal aortic aneurysm (AAA) and to investigate whether outcomes have improved over the years and whether there is an association between institutional caseload and peri-operative mortality. METHODS: Electronic information sources (MEDLINE, EMBASE, CINAHL and CENTRAL) were searched up to August 2019. A systematic review was carried out according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using a registered protocol (CRD42018106084). Studies were selected that reported peri-operative mortality of EVAR for ruptured AAA. A proportion meta-analysis was conducted, and summary estimates of odds ratios (ORs) and 95% confidence intervals (CIs) for EVAR vs. open surgical repair were obtained using random effects models. Mixed effects regression models were developed to investigate outcome changes over time and with institutional caseload. RESULTS: One hundred and thirty-six studies were included in quantitative synthesis reporting a total of 267 259 patients (EVAR 58 273; open surgery 208 986). The pooled peri-operative mortality of EVAR and open surgical repair was 0.245 (95% CI 0.234-0.257) and 0.378 (95% CI 0.364-0.392), respectively. EVAR was associated with reduced peri-operative mortality (OR 0.54, 95% CI 0.51-0.57, p < .001). Meta-regression analysis found decreasing peri-operative mortality over the years following EVAR (p < .001) and open repair (p < .001), and a decreasing OR of peri-operative mortality in favour of EVAR (p = .053). Meta-regression found a significant positive association between peri-operative mortality and institutional case load for open repair (p = .004). CONCLUSION: If EVAR can be done, it is a better treatment for ruptured AAA in view of the reduced peri-operative mortality compared with open surgery. The outcomes of both EVAR and open surgical repair have improved over the years, and the difference in peri-operative mortality in favour of EVAR has become more pronounced. There is a significant association between peri-operative mortality and institutional case load for open repair of ruptured AAA.

Does a previous aortic endograft confer any protective effect during abdominal aortic aneurysm rupture? Systematic review and meta-analysis of comparative studies.

OBJECTIVES: Whether prior endovascular aneurysm repair confers a protective effect in patients with ruptured abdominal aortic aneurysm (rAAA) is not known. We aimed to systematically review and compare the outcomes of rAAA in patients with and without prior endovascular aneurysm repair. METHODS: We performed a systematic review that conformed to the Preferred Reporting Items for Systematic Reviews and Meta-analysis. We selected studies comparing the outcomes in patients with rAAA after prior endovascular aneurysm repair (group 1) and those with de novo rAAAs (group 2). We conducted a proportion meta-analysis of perioperative mortality and obtained summary estimates of odds ratios (ORs) and 95% confidence intervals (CIs) using random-effects models. RESULTS: We included four studies (retrospective observational studies) in quantitative synthesis reporting a total of 719 patients (group 1 (89) group 2 (630)). The perioperative mortality in groups 1 and 2 was 30.4% and 41%, respectively, and there was no statistical significant difference between the groups (OR 0.66, 95% CI 0.30-1.43, P = 0.29, I2=58%). However, patients presenting with rAAA following previous endovascular aneurysm repair were more hemodynamically stable (OR 0.33, 95% CI 0.12-0.90, P = 0.03, I2=74%). The choice between endovascular or open surgery treatment in group 1 did not affect the perioperative mortality (OR 1.12, 95% CI 0.41-3.04 P = 0.82, I2=0%). Endoleak types I and III were the main causes of rAAA in group 1. CONCLUSIONS: Perioperative mortality was similar for rAAA either de novo or after prior endovascular aneurysm repair. However, ruptures in patients with prior endovascular aneurysm repair presented hemodynamically more stable.

CT Foot Perfusion Examination for Evaluation of Percutaneous Transluminal Angioplasty Outcome in Patients with Critical Limb Ischemia: A Feasibility Study.

PURPOSE: To evaluate foot perfusion in patients with critical limb ischemia (CLI) using quantitative perfusion multi-detector-row CT and estimate perfusion parameter changes before and after percutaneous transluminal angioplasty (PTA). MATERIALS AND METHODS: This prospective study investigated 13 patients (10 men; median age, 72 y; range, 51-84 y) with CLI who underwent CT foot perfusion examinations with a 128-slice dual-energy CT scanner 1 day before and 1 week after PTA. Key parameters such as permeability surface (PS), blood volume (BV), and blood flow (BF) were analyzed and compared statistically. The studies were also examined by a second observer to determine interobserver reproducibility. RESULTS: Revascularization was technically successful in all patients, and mean ankle-brachial index increased from 0.36 ± 0.16 to 0.75 ± 0.22. After revascularization, mean BV increased from 1.55 mL/100 g ± 0.83 to 4.51 mL/100 g ± 1.53, BF increased from 16.28 mL/100 g/min ± 4.97 to 31.49 mL/100 g/min ± 6.86, and PS increased from 3.1 mL/min/100 g ± 1.95 to 8.67 mL/min/100 g ± 3.85 (P < .05). Patients with poor response to revascularization who finally underwent amputation presented lower post-PTA perfusion parameters values than patients with significant clinical improvement (P < .05). All measurements demonstrated very good interobserver reproducibility, and intraclass correlation coefficients were 0.91 for BV, 0.94 for BF, and 0.95 for PS. The mean effective dose of the examination was estimated at 0.29 mSv. CONCLUSIONS: CT foot perfusion is a reproducible technique that may be a useful modality for the estimation of PTA outcome. Significant restitution of perfusion parameters was observed after successful revascularization.

Spontaneous Type Ia Endoleak Sealing in Patients Undergoing Endovascular Aneurysm Repair With the Ovation Stent Graft.

BACKGROUND: Type Ia endoleak may lead to continuous sac pressurization and late rupture after endovascular aneurysm repair (EVAR). Nevertheless, there have been scarce reports suggesting that these endoleaks may occasionally present spontaneous sealing. Taking into account the original sealing mechanism of the Ovation endograft that exploits 2 polymer-filled O-rings, we hypothesize that spontaneous type Ia endoleak sealing may sometimes incur following implantation of this device. We aim to report our experience with spontaneous type Ia endoleak sealing in patients treated with the Ovation endograft. METHODS: This is a retrospective observational study which included all patients undergoing EVAR with the Ovation endograft in a single institution during a 6-year period. Patients with an intraoperative type Ia endoleak were identified. The primary endpoint was rate of spontaneous sealing. Secondary endpoints were migration, sac expansion, need for reinterventions, secondary type Ia endoleaks, and aneurysm-related and overall mortality. Adherence to the instructions for use (IFU) was evaluated to examine relation with occurrence of endoleak and rates of spontaneous sealing. RESULTS: Among 147 patients treated, 8 (5%) left the operation theater with a type Ia endoleak. In 6 patients, the endoleak spontaneously resolved during a maximum of 3 months of follow-up. Among those, 5 cases were treated outside the IFU (2 short necks and 3 with severe angulation), while the sixth was a patient treated inside the IFU but was anticoagulated. In 2 patients, the endoleak did not spontaneously resolve. One presented a conical neck of marginal length and the other circumferential calcifications. Type Ia endoleak was significantly more common among patients treated in an off-label fashion. CONCLUSIONS: Spontaneous sealing of type Ia endoleak is common after EVAR with the Ovation endograft. Nonadherence to the IFU results in more endoleaks, but it does not seem to reduce possibilities for spontaneous sealing.

Has Anatomic Complexity of Abdominal Aortic Aneurysms Undergoing Open Surgical Repair Changed after the Introduction of Endovascular Treatment? Systematic Review and Meta-analysis of Comparative Studies.

BACKGROUND: At a time when endovascular aneurysm repair (EVAR) is increasingly used to treat abdominal aortic aneurysms (AAAs), lesions undergoing open surgical repair (OSR) may present significant differences compared with those treated before wide EVAR availability. We aim to record discrepancies in AAAs surgically treated before and after the introduction of EVAR. METHODS: We conducted a systematic review of the literature and meta-analysis of comparative studies. The MEDLINE, CENTRAL, and OpenGrey databases were searched up to October 2017. Outcome measures were anatomic complexity, procedural details, and postoperative outcomes. The random-effects model was used to calculate combined overall effect sizes. Data are presented as odds ratio (OR) or mean difference (MD) with 95% confidence intervals (CIs). RESULTS: Five observational studies were included. These involved 1,091 patients treated in the pre-EVAR era and 802 in the post-EVAR era. In general, patients undergoing OSR during the first period presented more comorbidities. Increased anatomic complexity was found among patients in the second group as demonstrated by the increased rate of suprarenal clamping (10.5% vs. 22.3%; OR, 0.34; 95% CI, 0.24-0.50), left renal vein division (10.3% vs. 18.8%; OR, 0.46; 95% CI, 0.25-0.88), iliac aneurysm (28.3% vs. 44.9%; OR, 0.48; 95% CI, 0.37-0.64), and iliac occlusive disease (13.1% vs. 20.2%; OR, 0.59; 95% CI, 0.39-0.88). Intraoperative use of blood products was greater during the latter period, but this difference did not reach statistical significance. Procedural duration was slightly increased in the same group. Morbidity and mortality were similar among the groups. CONCLUSIONS: After the wide availability of endoluminal grafting, more compromised patients tend to be managed with EVAR, leaving a fitter patient population to undergo OSR. At the same time, anatomic complexity of AAAs undergoing open surgery has considerably increased, requiring advanced proximal aortic surgical expertise to deal with these complex aortic pathologies Overall, morbidity and mortality remained unchanged, possibly due to the counterbalancing effects of these factors.

Variations of transverse foramina in cervical vertebrae: what happens to the vertebral artery?

PURPOSE: The purpose of this study is to examine variations of the foramen transversarium and the vertebral artery in computed tomography angiographies (CTa) of the cervical spine, investigate their coexistence, and present possible considerations regarding such variations in spine surgical procedures. METHODS: Fifty CTa of the neck were retrospectively reviewed. Transverse and anteroposterior diameter of the foramen and diameter of the vertebral artery were measured. Variations of the foramen and the vertebral artery were detected. RESULTS: Cervical CTa of 32 males and 18 females (mean age 66.4 ± 10.78 years), all belonging to the Indo-European race, were reviewed. Variations of the foramen transversarium were found in 17 vertebrae (4.85%) of 15 patients (30%). Duplication of the foramen was the most frequent variation, followed by the open foramen, the absence of the foramen, the triple foramen, and the hypoplastic foramen. Variations of the vertebral artery were found in 7 patients (14%) and asymmetry was found in 12 (24%) patients. Moreover, six patients presented with hypoplastic vertebral arteries (12%). When examining coexistence, 60% of patients exhibiting variations in the transverse foramen were also exhibiting variations or asymmetry in the vertebral artery, compared to 25.7% of patients with no foramen variations (p = 0.02). CONCLUSIONS: Vertebral artery injury is not common but may be a disastrous complication during cervical spine surgery. Proper preoperative planning is essential for any surgeon and exact knowledge of the anatomy in each patient is essential. This study strongly recommends the preoperative use of a CTa when suspicion of a variation is present and implied by a foramen variation. These slides can be retrieved under Electronic Supplementary Material.