The effect of aortic morphology on peri-operative mortality of ruptured abdominal aortic aneurysm

Endovascular Aneurysm Repair-First Strategy for Ruptured Abdominal Aortic Aneurysm Might Not Be Applicable to all Cases

BACKGROUND

We evaluate the relationship between the hospital case volume (HCV) and mortality outcomes after open aortic repair (OAR) and endovascular aortic repair (EVAR) of intact (iEVAR) and ruptured (rEVAR) abdominal aortic aneurysm (AAA) using a contemporary administrative database.

METHODS

The Healthcare Cost and Utilization Project Database for New York (2016) and New Jersey/Maryland/Florida (2016-2017) were queried using International Classification of Disease-10th edition to identify patients who had undergone OAR and EVAR. The hospitals were categorized into quartiles (Q) per overall (EVAR + OAR) volume, OAR-alone volume and EVAR-alone volume. Cox regression adjusted for confounding factors was used to estimate hazard ratios (HRs) for mortality.

RESULTS

A total of 8,825 patients (mean age, 73.5 ± 9.5 years; 6,861 male [77.7%]) had undergone 1,355 OARs and 7,470 EVARs. Overall HCV had no impact on in-hospital mortality across quartiles after (iEVAR) (range, 0.7%-1.4%, P = 0.15), (rEVAR) (range, 20.5%-29.6%, P = 0.63) and open repair of intact AAA (iOAR) (range, 4.9%-8.8%, P = 0.63). However, the mortality rates after open repair of ruptured AAA (rOAR) in highest-volume (Q4) hospitals were significantly lower than those in the 3 lower quartile hospitals (23.1% vs. 44.7%, P < 0.001). When analyzed per OAR-alone volume, the same findings were observed (22.0% for Q4 vs. 41.6% for Q1-3, P < 0.001). Furthermore, in Q4 hospitals per the OAR-alone volume analysis, the mortality hazard was greater for rEVAR (39.0%) than for rOAR (22.0%) (HR = 2.3, 95% confidence interval, 1.02-5.34, P < 0.05).

CONCLUSIONS

The mortality rates for iEVAR, rEVAR and iOAR were independent of HCV. However, after rOAR, mortality rates in high OAR volume hospitals were lower than those in the lower quartile hospitals, and, at least comparable to those of rEVAR. EVAR-first strategy for ruptured AAA might not be applicable to all cases. Patent-specific, individualized treatment should be the gold standard. For patients requiring rOAR, transfer to a regional center of excellence, when clinical safe, should be encouraged.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Nationwide Outcomes of Octogenarians Following Open or Endovascular Management After Ruptured Abdominal Aortic Aneurysms

PURPOSE

Octogenarians are known to have less-favorable outcomes following ruptured abdominal aortic aneurysm (rAAA) repair compared with their younger counterparts. Accurate information regarding perioperative outcomes following rAAA-repair is important to evaluate current treatment practice. The aim of this study was to evaluate perioperative outcomes of octogenarians and to identify factors associated with mortality and major complications after open surgical repair (OSR) or endovascular aneurysm repair (EVAR) of a rAAA using nationwide, real-world, contemporary data.

METHODS

All patients that underwent EVAR or OSR of an infrarenal or juxtarenal rAAA between January 1, 2013, and December 31, 2018, were prospectively registered in the Dutch Surgical Aneurysm Audit (DSAA) and included in this study. The primary outcome was the comparison of perioperative outcomes of octogenarians versus non-octogenarians, including adjustment for confounders. Secondary outcomes were the identification of factors associated with mortality and major complications in octogenarians.

RESULTS

The study included 2879 patients, of which 1146 were treated by EVAR (382 octogenarians, 33%) and 1733 were treated by OSR (410 octogenarians, 24%). Perioperative mortality of octogenarians following EVAR was 37.2% versus 14.8% in non-octogenarians (adjusted OR=2.9, 95% CI=2.8-3.0) and 50.0% versus 29.4% following OSR (adjusted OR=2.2, 95% CI=2.2-2.3). Major complication rates of octogenarians were 55.4% versus 31.8% in non-octogenarians following EVAR (OR=2.7, 95% CI=2.1-3.4), and 68% versus 49% following OSR (OR=2.2, 95% CI=1.8-2.8). Following EVAR, 30.6% of the octogenarians had an uncomplicated perioperative course (UPC) versus 49.5% in non-octogenarians (OR=0.5, 95% CI=0.4-0.6), while following OSR, UPC rates were 20.7% in octogenarians versus 32.6% in non-octogenarians (OR=0.5, 95% CI=0.4-0.7). Cardiac or pulmonary comorbidity and loss of consciousness were associated with mortality and major complications in octogenarians. Interestingly, female octogenarians had lower mortality rates following EVAR than male octogenarians (adjusted OR=0.7, 95% CI=0.6-0.8).

CONCLUSION

Based on this nationwide study with real-world registry data, mortality rates of octogenarians following ruptured AAA-repair were high, especially after OSR. However, a substantial proportion of these octogenarians following OSR and EVAR had an uneventful recovery. Known preoperative factors do influence perioperative outcomes and reflect current treatment practice.

Assessing Endovascular Aneurysm Repair Suitability According to Graft-Specific Instructions for Use in Patients With a Ruptured Abdominal Aortic Aneurysm

PURPOSE

The purpose of the study is to ascertain endovascular aneurysm repair (EVAR) suitability in relation to stent-graft-specific instructions for use (IFU) in patients with a ruptured abdominal aortic aneurysm (RAAA).

MATERIALS AND METHODS

Using the preoperative computed tomography angiography (CTA), the aortic morphology of patients undergoing surgical repair of a RAAA in 2 Dutch hospitals between January 2014 and December 2019 was retrospectively assessed. Three-dimensional and central luminal line reconstructions were used. Anatomical suitability was defined according to the IFU of the stent graft system used.

RESULTS

Of 128 included patients, 112 (88%) were men and the mean age was 74.1 (SD=7.6) years. Anatomy within IFU for EVAR was present in 31 patients (24%). Overall, 94 patients (73%) were treated with open surgical repair (OSR) and 34 patients (27%) were treated with EVAR. Anatomy within IFU was present in 15 OSR patients (16%) and 16 EVAR patients (47%). In patients with anatomy outside of IFU, 90% (87/97) had unsuitable neck anatomy and 64% (62/97) had insufficient neck length. An unsuitable distal iliac landing zone was observed in 35 patients. Perioperative mortality was 27% (34/128), with no difference between OSR and EVAR (25/94 vs 9/34; p=0.989).

CONCLUSION

Most RAAA patients in this series did not have aortic anatomy within IFU for EVAR, mainly due to insufficient neck length. However, whether anatomy outside of IFU equates to unsuitability for EVAR in an emergency setting remains a matter of debate and warrants further research.

CLINICAL IMPACT

The treatment of a ruptured abdominal aortic aneurysm can consist of endovascular repair or open repair. Retrospective anatomical assessment shows that most patients do not have anatomy inside the instructions for use for endovascular aneurysm repair, mainly due to insufficient neck length. Whether anatomy outside the instructions for use equates unsuitability for endovascular aneurysm repair remains a matter of debate.

Long-term Survival After Repair of Ruptured Abdominal Aortic Aneurysms Is Improving Over Time: Nationwide Analysis During Twenty-four Years in Sweden (1994-2017)

OBJECTIVE

To investigate long-term survival after ruptured abdominal aortic aneurysms (rAAA) repair in Sweden during twenty-four years (1994-2017).

SUMMARY BACKGROUND DATA

Management of rAAA has seen significant changes in the past decades, with the shifting from open (OAR) to endovascular (EVAR) being the most striking, thereby enabling treatment of elderly patients with multiple comorbidities.

METHODS

A registry-based nationwide cohort study was performed, and three 8-year periods (1994-2001, 2002-2009, 2010-2017) were compared for crude long-term survival with Kaplan-Meier and multivariable Cox proportional hazards analyses. Relative survival compared to matched general population referents was estimated.

RESULTS

Overall, 8928 rAAA repair subjects were identified (1994-2001 N = 3368; 2002-2009 N = 3405; 2010-2017 N = 2155). The proportion of octogenarians (20.6%; 27.5%; 34.0%; P < 0.001), women (14.3%; 18.5%; 20.6%; P < 0.001), and EVAR procedures (1.5%; 14.9%; 35.5%; P < 0.001) increased over time. The crude 5-year survival was 36%; 44%; 43% (P < 0.0001). Multivariable Cox proportional hazard analysis displayed a decreasing mortality hazard ratio (HR) over time (1.00; 0.80; 0.72; P < 0.001). Use of EVAR was associated with reduced hazards of crude long-term mortality (HR = 0.80, P < 0.001). Relative survival for patients surviving the perioperative period (ie, 90 days) was lower than matched general population referents, and was stable over time (relative 5-year survival: 86% vs 88%, vs 86% P < 0.001).

CONCLUSIONS

Nationwide analysis of long-term outcomes after repair of rAAA in Sweden during 24 years (1994-2017) has revealed that, despite changes in the baseline population characteristics as well as in the treatment strategy, long-term survival improved over time.

Sex difference in early mortality after abdominal aortic aneurysm repair

OBJECTIVE

Although female patients have a lower prevalence of abdominal aortic aneurysm (AAA), they seem to have a worse treatment outcome compared with male patients. Both maximum aneurysm diameter and aortic size index (ASI) are important indicators of the risk of AAA rupture, among which ASI has been shown capable of equalizing sex-related anatomical differences. Our study aimed to investigate whether sex is an independent risk factor for early postoperative mortality and how the diameter or ASI affects the association between sex and mortality.

METHODS

We performed a retrospective analysis of patients who enrolled in the AAA registry of the German Society of Vascular Surgery from 2013 to 2019. The patients were treated by either open surgical repair (OSR) or endovascular aneurysm repair (EVAR). The association between sex and 30-day mortality was investigated using logistic regression analysis. The interaction and mediating effects of maximum aneurysm diameter and ASI were investigated to verify their roles in the effect of sex on mortality. The relationships between the diameter (or ASI) and the risk of 30-day mortality in different sexes were demonstrated by the restricted cubic spline.

RESULTS

Overall, 23,275 cases were included in our analysis, with 20,130 male (86.5%) and 3139 female (13.5%) patients. Female patients had a smaller maximum aneurysm diameter (OSR, 55.23 ± 10.29 mm vs 58.05 ± 11.28 mm [P < .001]; EVAR, 54.06 ± 9.08 mm vs 56.11 ± 9.38 mm [P < .001]), but a higher ASI (OSR, 3.16 ± 0.71 vs 2.92 ± 0.69 [P < .001]; EVAR, 3.05 ± 0.66 vs 2.80 ± 0.59 [P < .001]) compared with male patients. The 30-day mortality rate was higher for female patients in both OSR (6.6% vs 4.2%; P = .002) and EVAR groups (1.8% vs 0.8%; P < .001). Logistic regression confirmed a significantly higher risk of 30-day mortality for female patients compared with male patients (odds ratio, 1.55; 95% confidence interval, 1.21-1.99; P = .001). No interaction was found between sex and diameter or ASI, but there were mediating effects for diameter and ASI in the effect of sex on 30-day mortality. For female patients, the risk of 30-day mortality linearly increased with the increase of diameter (P_Nonlinear = .089) or ASI (P_Nonlinear = .888), whereas the risk for male patients was U-shaped (for diameter, P_Nonlinear < .001; for ASI, P_Nonlinear = .020).

CONCLUSIONS

Sex is an independent risk factor for 30-day mortality after AAA repair. Both diameter and ASI are mediating factors for the effect of sex on 30-day mortality. The relationship between diameter or ASI and the risk of 30-day mortality is different for male and female patients.

Time Distribution of Mortality After Ruptured Abdominal Aortic Aneurysm Repair

BACKGROUND

Ruptured abdominal aortic aneurysm (rAAA) repair is still associated with high mortality. The aim of this population-based study was to analyze the time distribution of mortality and short-term mortality trends after rAAA repair.

METHODS

This was a nationwide retrospective registry study including all patients (n = 3,927) who underwent endovascular (EVAR) (n = 935) or open surgical repair (OSR) (n = 2,992) for rAAA between 2000 and 2018. The National Patient Register was used as a source to extract patient and medical data. The register was cross-linked with the national all-cause mortality registry. The postoperative time of death was divided into <48 hours, 2 to 5 days, 6 to 10 days, 11 to 20 days, 21 to 30 days, and 31 to 90 days during the year intervals 2000-2004, 2005-2009, 2010-2014, and 2015-2018, respectively. The proportion of patients who died within each postoperative time interval was calculated.

RESULTS

The overall median age was 75.0 years (interquartile range [IQR] 69.0-80.0) and females were 19.6% (n = 769). The EVAR cohort was older (77 vs. 65 years; P < 0.001) and had significantly more cardiovascular risk factors and a history of malignancy. The overall postoperative 90-day mortality was 33.2%, EVAR 25.7%, and OSR 35.5%. There was an overall improvement in 90-day mortality over time (odds ratio [OR] 0.70; 95% confidence interval [CI] 0.57-0.87; P = 0.001) but not separately for EVAR or OSR. Analyzing all postoperative mortalities within 90 days, 43.4% of deaths occurred within 48 hours followed by 16.3% in 2-5 days. The distribution of mortality proportions in each time interval after OSR was 15.4% in < 48 hours, 7.3% in 2-5 days, 4.4% in 6-10 days, 8.6% in 11-30 days, and 6.0% in 31-90 days and after EVAR 11.1% < 48 hours, 3.6% 2-5 days, 3.1% 6-10 days, 4.6% 11-30 days, and 6% 31-90 days. The overall mortality proportions for patients who died <48 hours after aortic repair had decreased over time (P = 0.024). A logistic regression analysis found the following risk factors associated with mortality <48 hours after rAAA, open repair (OR 1.48; 95% CI 1.17-1.89; P = 0.001), female gender (OR 1.41; 95% CI 1.14-1.75; P = 0.002), and history of heart failure (OR 1.63; 95% CI 1.19-2.22; P = 0.002) or angina pectoris (OR 1.37; 95% CI 1.03-1.81; P = 0.03). The recent operative year interval, 2015-2018, was associated with a lower risk for mortality <48 hours (OR 0.72; 95% 0.53-0.98; P = 0.04) and <90-days (OR 0.63; 95% CI 0.49-0.80; P < 0.001).

CONCLUSIONS

Overall mortality after rAAA repair had decreased but early deaths remained a significant challenge. The mortality was highest within two days of surgery but the proportion of patients who died <48 hours after aortic repair had decreased in recent years. Open repair, female gender, and cardiovascular comorbidities were associated with mortality within 48 hours after surgery. More focused research in the early postoperative phase after rAAA is warranted.

Comparison between endovascular aneurysm repair-selected and endovascular aneurysm repair-only strategies for the management of ruptured abdominal aortic aneurysms: An 11-year experience at a Chinese tertiary hospital

Objectives

The aim of this study was to review our management experience of ruptured abdominal aortic aneurysms (RAAAs) using an endovascular aneurysm repair (EVAR)-only strategy, and discuss the feasibility of this strategy.

Materials and methods

A retrospective analysis of clinical data was performed in patients with RAAAs from January 2009 to October 2020. Our strategy toward operative treatment for RAAAs evolved from an EVAR-selected (from January 2009 to April 2014) to an EVAR-only (from May 2014 to October 2020) strategy. Baseline characteristics, thirty-day mortality, perioperative complications, and long-term outcomes of patients were compared between the two periods.

Results

A total of 93 patients undergoing emergent RAAA repair were eventually included. The overall operation rate in RAAAs at our centre was 70.5% (93/132). In the EVAR-only period, all 53 patients underwent ruptured endovascular aneurysm repair (rEVAR). However, only 47.5% (19/40) of patients in the EVAR-selected period underwent rEVAR, and the remaining 21 patients underwent emergent open surgery. Thirty-day mortality in the EVAR-only group was 22.6% (12/53) compared with 25.0% (10/40) for the EVAR-selected group (P = 0.79). Systolic blood pressure ≤70 mmHg [adjusted odds ratio (OR) 4.99, 95% confidence interval (CI), 1.13–22.08, P = 0.03] and abdominal compartment syndrome (adjusted OR 3.72, 95% CI, 1.12–12.32, P = 0.03) were identified as independent risk factors responsible for 30-day mortality. After 5 years, 47.5% (95% CI, 32.0–63.0%) of patients in the EVAR-selected group were still alive versus 49.1% (95% CI, 32.3–65.9%) of patients in the EVAR-only group (P = 0.29).

Conclusion

The EVAR-only strategy has allowed rEVAR to be used in nearly all the RAAAs with similar mortality comparing with the EVAR-selected strategy. Due to the avoidance of operative modality selection, the EVAR-only strategy was associated with a more simplified algorithm, less influence on haemodynamics, and a shorter operation and recovery time.

[Endovascular aneurysm repair (EVAR) : Update D]

BACKGROUND

Abdominal aortic aneurysms can either be treated by open surgery or endovascular repair. In both cases, prostheses are implanted to prevent potentially lethal aortic ruptures.

OBJECTIVES

Studies seeking to identify the optimal treatment came to diverging conclusions. The goal of this article is to shed light on the discussion of which treatment option is to be preferred.

MATERIALS AND METHODS

This article summarizes the relevant studies on elective and emergency abdominal aortic aneurysm repair. The presented studies are discussed, and results are interpreted and compared.

RESULTS

While most studies indicate lower short-term mortality rates in endovascular aneurysm repair (EVAR), mortality rates converged in multiple trials and even showed a lower mortality rate for open repair in mid-term analyses. Most recent studies indicate long-term equivalence in terms of mortality and a higher rate of secondary interventions in EVAR patients.

CONCLUSIONS

The current body of literature indicates no real advantage of one therapy over another. The choice of therapy should depend on anatomic, clinical, and logistic criteria.

A Comparison of Endovascular Aneurysm Repair and Open Repair for Ruptured Aortic Abdominal Aneurysms

Management modalities of ruptured abdominal aortic aneurysm (AAA) include ruptured open aneurysm repair (rOAR) and ruptured endovascular aneurysm repair (rEVAR). In this study, we aim to systematically review all the previously published randomized controlled trials (RCTs) that compared rOAR and rEVAR. A systematic search was performed in the following databases: PubMed, Scopus, Web of Science, Google Scholar, Clinical trials, and others with all the potentially relevant keywords that were adjusted to meet the search strategy for each database to collect all the relevant studies that were published up to January 2021. A total of 11 studies were identified through our comprehensive search. Among these studies, seven represented the IMPROVE trial, two represented the AJAX trial, and two represented the Nottingham and ECAR trials, each, while the remaining four studies were not RCTs; however, these were included in the discussion as they obtained data from the IMPROVE trial. The IMPROVE trials preferred EVAR use due to the potential survival benefit and improved quality of life, although the EVAR and OAR had similar mortality rates. In the AJAX and ECAR, the mortality rates favored EVAR over OAR with no significance while the opposite was noticed in the Nottingham trial with no significance also. Similar rates of re-interventions and complications were also noticed and some studies reported that EVAR is cost-effective. Overall evidence slightly favors EVAR over OAR and further studies are needed.

Risk Factors for Abdominal Compartment Syndrome After Endovascular Repair for Ruptured Abdominal Aortic Aneurysm: A Case Control Study

OBJECTIVE

Ruptured abdominal aortic aneurysms (rAAA) are treated by endovascular aneurysm repair (rEVAR) increasingly often. Despite rEVAR being a minimally invasive method, abdominal compartment syndrome (ACS) remains a significant post-operative threat. The aim of this study was to investigate risk factors for ACS after rEVAR, including aortic morphological features.

METHODS

The Swedish vascular registry (Swedvasc) was assessed for ACS after rEVAR in the period 2008 - 2015. All patients identified were compared with controls (i.e., patients who did not develop ACS after rEVAR), matched by centre and repair date. Case records were reviewed, and radiology images analysed in a core laboratory. Comparisons were performed with respect to physiological and radiological risk factors.

RESULTS

The study population consisted of 40 patients with ACS and 68 controls. Pre-operatively, patients with ACS had a lower blood pressure (BP) than controls (median 70 mmHg vs. 97 mmHg; p < .001). Intra-operatively, they had aortic balloon occlusion more often (55.0% vs. 10.3%; p < .001) and received more transfusions than controls (median nine units of packed red blood cells [pRBC] vs. two units; p < .001). Ninety-seven per cent of those who developed ACS had a pre-operative BP < 70 mmHg, aortic balloon occlusion, or received more than five pRBC unit transfusions. Treatment outside the instructions for use did not differ between patients and controls (57.5% vs. 54.4%; p = .84), and neither did the pre-operative patency of the inferior mesenteric artery (57.1% vs. 63.9%; p = .52) nor the number of visible lumbar arteries on pre-operative imaging (2 vs. 4; p = .014). In multivariable logistic regression, the number of intra-operative transfusions were predictive of ACS (p < .001), while pre-operative hypotension (p = .32) and aortic balloon occlusion (p = .018) were not.

CONCLUSION

ACS after rEVAR is mainly associated with physiological factors and is unlikely to develop without the presence of a pre-operative BP < 70 mmHg, the need for an aortic occlusion balloon, or more than five intra-operative pRBC unit transfusions. Treatment outside the IFU or any other morphological factor were not associated with a risk of ACS.

Results from a nationwide prospective registry on open surgical or endovascular repair of juxtarenal abdominal aortic aneurysms

BACKGROUND

Juxtarenal abdominal aortic aneurysms (JRAAA) can be treated either with open surgical repair (OSR) including suprarenal clamping or by complex endovascular aneurysm repair (cEVAR). In this study we present the comparison between the short-term mortality and complications of the elective JRAAA treatment modalities from a national database reflecting daily practice in the Netherlands.

METHODS

All patients undergoing elective JRAAA open repair or cEVAR (fenestrated EVAR or chimney EVAR) between January 2016 and December 2018 registered in the Dutch Surgical Aneurysm Audit (DSAA) were eligible for inclusion. Descriptive perioperative variables and outcomes were compared between patients treated with open surgery or endovascularly. Adjusted odds ratios for short-term outcomes were calculated by logistic regression analysis.

RESULTS

In all, 455 primary treated JRAAA patients could be included (258 OSR, 197 cEVAR). Younger patients and female patients were treated more often with OSR vs cEVAR (72±6.1 vs. 76±6.0, p<0.001, 22% vs 15%, p=0.047, respectively). Patients treated with OSR had significantly more major and minor complications as well as a higher chance of early mortality (OSR: cEVAR, 45% vs. 21%, p<0.001; 34% vs. 23%, p =0.011; 6.6% vs. 2.5%, p=0.046, respectively). After logistic regression with adjustment for confounders, patients who were treated with OSR showed an odds ratio of 3.64 (95%CI 2.25-5.89, p<0.001) for major complications compared to patients treated with cEVAR and for minor complications the odds ratios were 2.17 (95%CI 1.34-3.53, p=0.002) higher. For early mortality the odds ratios were 3.79 (95%CI 1.26-11.34, p=0.017) higher after OSR compared to cEVAR.

CONCLUSION

In this study, after primary elective OSR for JRAAA the odds for major complications, minor complications, and short-term mortality were significantly higher compared to cEVAR.

Aneurysm Volumes After Endovascular Repair of Ruptured vs Intact Aortic Aneurysms: A Retrospective Observational Study

Purpose

To compare changes in abdominal aortic aneurysm (AAA) sac volume between endovascular aneurysm repairs (EVAR) performed for ruptured (rEVAR) vs intact (iEVAR) AAAs and to determine the impact of early volume shrinkage on future complications.

Materials and Methods

A retrospective analysis was performed of all patients undergoing standard infrarenal EVAR from 2002 to 2016 at a tertiary referral institution. Only patients with degenerative AAAs and with 30-day and 1-year computed tomography angiography (CTA) imaging were included. Early sac shrinkage was defined as a volume sac reduction >10% between the first (<30-day) and the 1-year CTA. The primary endpoint was to compare AAA sac volume changes between patients undergoing rEVAR (n=51; mean age 71.0±8.5 years; 46 men) vs iEVAR (n=393; mean age 72.3±7.5 years; 350 men). Results are reported as the mean difference with the interquartile range (IQR Q1, Q3). The secondary endpoint was freedom from aneurysm-related complications after 1 year as determined by regression analysis; the results are presented as the hazard ratio (HR) and 95% confidence interval (CI).

Results

At baseline, the rEVAR group had larger aneurysms (p<0.001) and shorter (p<0.001) and more angulated (p=0.028) necks. Aneurysm sac volume decreased more in the rEVAR group during the first year [−26.3% (IQR −38.8%, −12.5%)] vs the iEVAR group [−11.9% (IQR −27.5%, 0); p<0.001]. However, after the first year, the change in sac volume was similar between the groups [−3.8% (IQR −32.9%, 31.9%) for rEVAR and −1.5% (IQR −20.9%, 13.6%) for iEVAR, p=0.74]. Endoleak occurrence during follow-up was similar between the groups. In the overall population, patients with early sac shrinkage had a lower incidence of complications after the 1-year examination (adjusted HR 0.59, 95% CI 0.39 to 0.89, p=0.01).

Conclusion

EVAR patients treated for rupture have more pronounced aneurysm sac shrinkage compared with iEVAR patients during the first year after EVAR. Patients presenting with early shrinkage are less likely to encounter late complications. These parameters may be considered when tailoring surveillance protocols.

Abdominal aortic aneurysms part one: Epidemiology, presentation and preoperative considerations

An abdominal aortic aneurysm is an irreversible dilatation of the abdominal aorta. The majority of abdominal aortic aneurysms are asymptomatic and identified incidentally while investigating a separate pathology. Others are detected by national screening programmes and some present due to a growth or rupture. Symptomatic or ruptured aneurysms require urgent or emergency repair in patients fit for surgery. Perioperative practitioners should therefore be aware of how patients with abdominal aortic aneurysms present and are investigated, so that they can implement timely management. Guidelines have been recently updated to reflect this. This literature review discusses these recommendations and explores the evidence upon which they are based. The aim of this article is to highlight the important preoperative principles that need to be considered in cases of abdominal aortic aneurysm.

Suitability of the Aortic Neck Anatomy for Endovascular Aneurysm Repair in Korean Patients with Abdominal Aortic Aneurysm

Purpose

To evaluate the aortic neck anatomy in Korean patients with abdominal aortic aneurysms (AAAs).

Materials and Methods

We examined computed tomography scans of 343 patients with AAAs (≥5.5 cm for men or ≥5 cm for women) between 2009 and 2018. Eligibility of neck anatomy for endovascular aneurysm repair (EVAR) was assessed with the standard instructions for use (IFU) (length ≥15 mm, suprarenal angulation (SRA) ≤45°, infrarenal angulation (IRA) ≤60°, and diameter 18-32 mm) and the extended IFU (length ≥10 mm, SRA ≤60°, IRA ≤75°, and diameter 17-32 mm).

Results

There were 71 women (20.7%), and 61 patients (17.8%) with rupture. Women had smaller neck diameters (21.3 vs. 23.4 mm, P<0.001 for proximal neck; 22.2 vs. 24.5 mm, P<0.001 for distal neck), and higher angulations (51.5° vs. 37.8°, P<0.001 for SRA; 77.7° vs. 57.0°, P<0.001 for IRA) than men. However, the neck length was not significantly different. Patients with ruptured AAAs had shorter neck lengths (21.0 vs. 26.8 mm, P=0.005) than those with intact AAAs. However, the neck diameters and angulations were not significantly different. EVAR eligibility for standard and extended IFUs was found in 37.5% and 55.1% of men, and 11.3% and 25.4% of women (P<0.001 for both IFUs); neck anatomy was eligible in 34.0% of intact AAAs and 23.0% of ruptured AAAs (P=0.098).

Conclusion

A significant proportion of the Korean patients did not meet the IFU for EVAR, mainly due to the angulated neck. Women, and patients with ruptured AAAs, were less likely to meet the IFU criteria.

Strategy of endovascular versus open repair for patients with clinical diagnosis of ruptured abdominal aortic aneurysm: the IMPROVE RCT

BACKGROUND

Ruptured abdominal aortic aneurysm (AAA) is a common vascular emergency. The mortality from emergency endovascular repair may be much lower than the 40-50% reported for open surgery.

OBJECTIVE

To assess whether or not a strategy of endovascular repair compared with open repair reduces 30-day and mid-term mortality (including costs and cost-effectiveness) among patients with a suspected ruptured AAA.

DESIGN

Randomised controlled trial, with computer-generated telephone randomisation of participants in a 1 : 1 ratio, using variable block size, stratified by centre and without blinding.

SETTING

Vascular centres in the UK (n = 29) and Canada (n = 1) between 2009 and 2013.

PARTICIPANTS

A total of 613 eligible participants (480 men) with a ruptured aneurysm, clinically diagnosed at the trial centre.

INTERVENTIONS

A total of 316 participants were randomised to the endovascular strategy group (immediate computerised tomography followed by endovascular repair if anatomically suitable or, if not suitable, open repair) and 297 were randomised to the open repair group (computerised tomography optional).

MAIN OUTCOME MEASURES

The primary outcome measure was 30-day mortality, with 30-day reinterventions, costs and disposal as early secondary outcome measures. Later outcome measures included 1- and 3-year mortality, reinterventions, quality of life (QoL) and cost-effectiveness.

RESULTS

The 30-day mortality was 35.4% in the endovascular strategy group and 37.4% in the open repair group [odds ratio (OR) 0.92, 95% confidence interval (CI) 0.66 to 1.28; p = 0.62, and, after adjustment for age, sex and Hardman index, OR 0.94, 95% CI 0.67 to 1.33]. The endovascular strategy appeared to be more effective in women than in men (interaction test p = 0.02). More discharges in the endovascular strategy group (94%) than in the open repair group (77%) were directly to home (p < 0.001). Average 30-day costs were similar between groups, with the mean difference in costs being -£1186 (95% CI -£2997 to £625), favouring the endovascular strategy group. After 1 year, survival and reintervention rates were similar in the two groups, QoL (at both 3 and 12 months) was higher in the endovascular strategy group and the mean cost difference was -£2329 (95% CI -£5489 to £922). At 3 years, mortality was 48% and 56% in the endovascular strategy group and open repair group, respectively (OR 0.73, 95% CI 0.53 to 1.00; p = 0.053), with a stronger benefit for the endovascular strategy in the subgroup of 502 participants in whom repair was started for a proven rupture (OR 0.62, 95% CI 0.43 to 0.89; p = 0.009), whereas aneurysm-related reintervention rates were non-significantly higher in this group. At 3 years, considering all participants, there was a mean difference of 0.174 quality-adjusted life-years (QALYs) (95% CI 0.002 to 0.353 QALYs) and, among the endovascular strategy group, a cost difference of -£2605 (95% CI -£5966 to £702), leading to 88% of estimates in the cost-effectiveness plane being in the quadrant showing the endovascular strategy to be 'dominant'.

LIMITATIONS

Because of the pragmatic design of this trial, 33 participants in the endovascular strategy group and 26 in the open repair group breached randomisation allocation.

CONCLUSIONS

The endovascular strategy was not associated with a significant reduction in either 30-day mortality or cost but was associated with faster participant recovery. By 3 years, the endovascular strategy showed a survival and QALY gain and was highly likely to be cost-effective. Future research could include improving resuscitation for older persons with circulatory collapse, the impact of local anaesthesia and emergency consent procedures.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN48334791 and NCT00746122.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 31. See the NIHR Journals Library website for further project information.

Screening women aged 65 years or over for abdominal aortic aneurysm: a modelling study and health economic evaluation

BACKGROUND

Abdominal aortic aneurysm (AAA) screening programmes have been established for men in the UK to reduce deaths from AAA rupture. Whether or not screening should be extended to women is uncertain.

OBJECTIVE

To evaluate the cost-effectiveness of population screening for AAAs in women and compare a range of screening options.

DESIGN

A discrete event simulation (DES) model was developed to provide a clinically realistic model of screening, surveillance, and elective and emergency AAA repair operations. Input parameters specifically for women were employed. The model was run for 10 million women, with parameter uncertainty addressed by probabilistic and deterministic sensitivity analyses.

SETTING

Population screening in the UK.

PARTICIPANTS

Women aged ≥ 65 years, followed up to the age of 95 years.

INTERVENTIONS

Invitation to ultrasound screening, followed by surveillance for small AAAs and elective surgical repair for large AAAs.

MAIN OUTCOME MEASURES

Number of operations undertaken, AAA-related mortality, quality-adjusted life-years (QALYs), NHS costs and cost-effectiveness with annual discounting.

DATA SOURCES

AAA surveillance data, National Vascular Registry, Hospital Episode Statistics, trials of elective and emergency AAA surgery, and the NHS Abdominal Aortic Aneurysm Screening Programme (NAAASP).

REVIEW METHODS

Systematic reviews of AAA prevalence and, for elective operations, suitability for endovascular aneurysm repair, non-intervention rates, operative mortality and literature reviews for other parameters.

RESULTS

The prevalence of AAAs (aortic diameter of ≥ 3.0 cm) was estimated as 0.43% in women aged 65 years and 1.15% at age 75 years. The corresponding attendance rates following invitation to screening were estimated as 73% and 62%, respectively. The base-case model adopted the same age at screening (65 years), definition of an AAA (diameter of ≥ 3.0 cm), surveillance intervals (1 year for AAAs with diameter of 3.0-4.4 cm, 3 months for AAAs with diameter of 4.5-5.4 cm) and AAA diameter for consideration of surgery (5.5 cm) as in NAAASP for men. Per woman invited to screening, the estimated gain in QALYs was 0.00110, and the incremental cost was £33.99. This gave an incremental cost-effectiveness ratio (ICER) of £31,000 per QALY gained. The corresponding incremental net monetary benefit at a threshold of £20,000 per QALY gained was -£12.03 (95% uncertainty interval -£27.88 to £22.12). Almost no sensitivity analyses brought the ICER below £20,000 per QALY gained; an exception was doubling the AAA prevalence to 0.86%, which resulted in an ICER of £13,000. Alternative screening options (increasing the screening age to 70 years, lowering the threshold for considering surgery to diameters of 5.0 cm or 4.5 cm, lowering the diameter defining an AAA in women to 2.5 cm and lengthening the surveillance intervals for the smallest AAAs) did not bring the ICER below £20,000 per QALY gained when considered either singly or in combination.

LIMITATIONS

The model for women was not directly validated against empirical data. Some parameters were poorly estimated, potentially lacking relevance or unavailable for women.

CONCLUSION

The accepted criteria for a population-based AAA screening programme in women are not currently met.

FUTURE WORK

A large-scale study is needed of the exact aortic size distribution for women screened at relevant ages. The DES model can be adapted to evaluate screening options in men.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42015020444 and CRD42016043227.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Abdominal Aortic Aneurysm: Evolving Controversies and Uncertainties

Abdominal aortic aneurysm (AAA) is defined as a permanent dilatation of the abdominal aorta that exceeds 3 cm. Most AAAs arise in the portion of abdominal aorta distal to the renal arteries and are defined as infrarenal. Most AAAs are totally asymptomatic until catastrophic rupture. The strongest predictor of AAA rupture is the diameter. Surgery is indicated to prevent rupture when the risk of rupture exceeds the risk of surgery. In this review, we aim to analyze this disease comprehensively, starting from an epidemiological perspective, exploring etiology and pathophysiology, and concluding with surgical controversies. We will pursue these goals by addressing eight specific questions regarding AAA: (1) Is the incidence of AAA increasing? (2) Are ultrasound screening programs for AAA effective? (3) What causes AAA: Genes versus environment? (4) Animal models: Are they really relevant? (5) What pathophysiology leads to AAA? (6) Indications for AAA surgery: Are surgeons over-eager to operate? (7) Elective AAA repair: Open or endovascular? (8) Emergency AAA repair: Open or endovascular?

Editor's Choice - Re-interventions After Repair of Ruptured Abdominal Aortic Aneurysm: A Report From the IMPROVE Randomised Trial

OBJECTIVE/BACKGROUND

The aim was to describe the re-interventions after endovascular and open repair of rupture, and investigate whether these were associated with aortic morphology.

METHODS

In total, 502 patients from the IMPROVE randomised trial (ISRCTN48334791) with repair of rupture were followed-up for re-interventions for at least 3 years. Pre-operative aortic morphology was assessed in a core laboratory. Re-interventions were described by time (0-90 days, 3 months-3 years) as arterial or laparotomy related, respectively, and ranked for severity by surgeons and patients separately. Rare re-interventions to 1 year, were summarised across three ruptured abdominal aortic aneurysm trials (IMPROVE, AJAX, and ECAR) and odds ratios (OR) describing differences were pooled via meta-analysis.

RESULTS

Re-interventions were most common in the first 90 days. Overall rates were 186 and 226 per 100 person years for the endovascular strategy and open repair groups, respectively (p = .20) but between 3 months and 3 years (mid-term) the rates had slowed to 9.5 and 6.0 re-interventions per 100 person years, respectively (p = .090) and about one third of these were for a life threatening condition. In this latter, mid-term period, 42 of 313 remaining patients (13%) required at least one re-intervention, most commonly for endoleak or other endograft complication after treatment by endovascular aneurysm repair (EVAR) (21 of 38 re-interventions), whereas distal aneurysms were the commonest reason (four of 23) for re-interventions after treatment by open repair. Arterial re-interventions within 3 years were associated with increasing common iliac artery diameter (OR 1.48, 95% confidence interval [CI] 0.13-0.93; p = .004). Amputation, rare but ranked as the worst re-intervention by patients, was less common in the first year after treatment with EVAR (OR 0.2, 95% CI 0.05-0.88) from meta-analysis of three trials.

CONCLUSION

The rate of mid-term re-interventions after rupture is high, more than double that after elective EVAR and open repair, suggesting the need for bespoke surveillance protocols. Amputations are much less common in patients treated by EVAR than in those treated by open repair.

Value of risk scores in the decision to palliate patients with ruptured abdominal aortic aneurysm

Background

The aim of this study was to develop a 48‐h mortality risk score, which included morphology data, for patients with ruptured abdominal aortic aneurysm presenting to an emergency department, and to assess its predictive accuracy and clinical effectiveness in triaging patients to immediate aneurysm repair, transfer or palliative care.

Methods

Data from patients in the IMPROVE (Immediate Management of the Patient With Ruptured Aneurysm: Open Versus Endovascular Repair) randomized trial were used to develop the risk score. Variables considered included age, sex, haemodynamic markers and aortic morphology. Backwards selection was used to identify relevant predictors. Predictive performance was assessed using calibration plots and the C‐statistic. Validation of the newly developed and other previously published scores was conducted in four external populations. The net benefit of treating patients based on a risk threshold compared with treating none was quantified.

Results

Data from 536 patients in the IMPROVE trial were included. The final variables retained were age, sex, haemoglobin level, serum creatinine level, systolic BP, aortic neck length and angle, and acute myocardial ischaemia. The discrimination of the score for 48‐h mortality in the IMPROVE data was reasonable (C‐statistic 0·710, 95 per cent c.i. 0·659 to 0·760), but varied in external populations (from 0·652 to 0·761). The new score outperformed other published risk scores in some, but not all, populations. An 8 (95 per cent c.i. 5 to 11) per cent improvement in the C‐statistic was estimated compared with using age alone.

Conclusion

The assessed risk scores did not have sufficient accuracy to enable potentially life‐saving decisions to be made regarding intervention. Focus should therefore shift to offering repair to more patients and reducing non‐intervention rates, while respecting the wishes of the patient and family.

Not much help

Editor's Choice - The Impact of Centralisation and Endovascular Aneurysm Repair on Treatment of Ruptured Abdominal Aortic Aneurysms Based on International Registries

OBJECTIVES

Current management of ruptured abdominal aortic aneurysms (RAAA) varies among centres and countries, particularly in the degree of implementation of endovascular aneurysm repair (EVAR) and levels of vascular surgery centralisation. This study assesses these variations and the impact they have on outcomes.

MATERIALS AND METHODS

RAAA repairs from vascular surgical registries in 11 countries, 2010-2013, were investigated. Data were analysed overall, per country, per treatment modality (EVAR or open aortic repair [OAR]), centre volume (quintiles IV), and whether centres were predominantly EVAR (≥50% of RAAA performed with EVAR [EVAR(p)]) or predominantly OAR [OAR(p)]. Primary outcome was peri-operative mortality. Data are presented as either mean values or percentages with 95% CI within parentheses, and compared with chi-square tests, as well as with adjusted OR.

RESULTS

There were 9273 patients included. Mean age was 74.7 (74.5-74.9) years, and 82.7% of patients were men (81.9-83.6). Mean AAA diameter at rupture was 7.6 cm (7.5-7.6). Of these aneurysms, 10.7% (10.0-11.4) were less than 5.5 cm. EVAR was performed in 23.1% (22.3-24.0). There were 6817 procedures performed in OAR(p) centres and 1217 performed in EVAR(p) centres. Overall peri-operative mortality was 28.8% (27.9-29.8). Peri-operative mortality for OAR was 32.1% (31.0-33.2) and for EVAR 17.9% (16.3-19.6), p < .001, and the adjusted OR was 0.38 (0.31-0.47), p < .001. The peri-operative mortality was 23.0% in EVAR(p) centres (20.6-25.4), 29.7% in OAR(p) centres (28.6-30.8), p < .001; adjusted OR = 0.60 (0.46-0.78), p < .001. Peri-operative mortality was lower in the highest volume centres (QI > 22 repairs per year), 23.3% (21.2-25.4) than in QII-V, 30.0% (28.9-31.1), p < .001. Peri-operative mortality after OAR was lower in high volume centres compared with the other centres, 25.3% (23.0-27.6) and 34.0% (32.7-35.4), respectively, p < .001. There was no significant difference in peri-operative mortality after EVAR between centres based on volume.

CONCLUSIONS

Peri-operative mortality is lower in centres with a primary EVAR approach or with high case volume. Most repairs, however, are still performed in low volume centres and in centres with a primary OAR strategy. Reorganisation of acute vascular surgical services may improve outcomes of RAAA repair.

Comparative clinical effectiveness and cost effectiveness of endovascular strategy v open repair for ruptured abdominal aortic aneurysm: three year results of the IMPROVE randomised trial

Objective To assess the three year clinical outcomes and cost effectiveness of a strategy of endovascular repair (if aortic morphology is suitable, open repair if not) versus open repair for patients with suspected ruptured abdominal aortic aneurysm.Design Randomised controlled trial.Setting 30 vascular centres (29 in UK, one in Canada), 2009-16.Participants 613 eligible patients (480 men) with a clinical diagnosis of ruptured aneurysm, of whom 502 underwent emergency repair for rupture.Interventions 316 patients were randomised to an endovascular strategy (275 with confirmed rupture) and 297 to open repair (261 with confirmed rupture).Main outcome measures Mortality, with reinterventions after aneurysm repair, quality of life, and hospital costs to three years as secondary measures.Results The maximum follow-up for mortality was 7.1 years, with two patients in each group lost to follow-up by three years. After similar mortality by 90 days, in the mid-term (three months to three years) there were fewer deaths in the endovascular than the open repair group (hazard ratio 0.57, 95% confidence interval 0.36 to 0.90), leading to lower mortality at three years (48% v 56%), but by seven years mortality was about 60% in each group (hazard ratio 0.92, 0.75 to 1.13). Results for the 502 patients with repaired ruptures were more pronounced: three year mortality was lower in the endovascular strategy group (42% v 54%; odds ratio 0.62, 0.43 to 0.88), but after seven years there was no clear difference between the groups (hazard ratio 0.86, 0.68 to 1.08). Reintervention rates up to three years were not significantly different between the randomised groups (hazard ratio 1.02, 0.79 to 1.32); the initial rapid rate of reinterventions was followed by a much slower mid-term reintervention rate in both groups. The early higher average quality of life in the endovascular strategy versus open repair group, coupled with the lower mortality at three years, led to a gain in average quality adjusted life years (QALYs) at three years of 0.17 (95% confidence interval 0.00 to 0.33). The endovascular strategy group spent fewer days in hospital and had lower average costs of -£2605 (95% confidence interval -£5966 to £702) (about €2813; $3439). The probability that the endovascular strategy is cost effective was >90% at all levels of willingness to pay for a QALY gain.Conclusions At three years, compared with open repair, an endovascular strategy for suspected ruptured abdominal aortic aneurysm was associated with a survival advantage, a gain in QALYs, similar levels of reintervention, and reduced costs, and this strategy was cost effective. These findings support the increasing use of an endovascular strategy, with wider availability of emergency endovascular repair.Trial registration Current Controlled Trials ISRCTN48334791; ClinicalTrials NCT00746122.

Open versus endovascular repair of ruptured abdominal aortic aneurysms: What have we learned after more than 2 decades of ruptured endovascular aneurysm repair?

BACKGROUND

Ruptured abdominal aortic aneurysm is one of the most difficult clinical problems in surgical practice, with extraordinarily high morbidity and mortality. During the past 23 years, the literature has become replete with reports regarding ruptured endovascular aneurysm repair.

METHODS

A variety of study designs and databases have been utilized to compare ruptured endovascular aneurysm repair and open surgical repair for ruptured abdominal aortic aneurysm and studies of various designs from different databases have yielded vastly different conclusions. It therefore remains controversial whether ruptured endovascular aneurysm repair improves outcomes after ruptured abdominal aortic aneurysm in comparison to open surgical repair.

RESULTS

The purpose of this article is to review the best available evidence comparing ruptured endovascular aneurysm repair and open surgical repair of ruptured abdominal aortic aneurysm, including single institution and multi-institutional retrospective observational studies, large national population-based studies, large national registries of prospectively collected data, and randomized controlled clinical trials.

CONCLUSION

This article will analyze the study designs and databases utilized with their attendant strengths and weaknesses to understand the sometimes vastly different conclusions the studies have reached. This article will attempt to integrate the data to distill some of the lessons that have been learned regarding ruptured endovascular aneurysm repair and identify ongoing needs in this field.

Surgical Versus Endovascular Aortic Aneurysm Repair: Evidence to Guide the Optimal Approach for the Individual Patient

The choice between an open surgical and an endovascular approach for abdominal aortic aneurysm (AAA) repair remains an individualized clinical decision. As the technology and applications of endovascular aortic aneurysm repair (EVAR) continue to evolve, so does the literature investigating its outcomes. Multiple high-quality, randomized controlled trials comparing EVAR to open surgical repair (OSR) have now been published with long-term follow-up. Experience with ruptured aneurysms and the use of complex endografts is growing as well. This review is an up-to-date compilation of pertinent clinical trials for practitioners placed in the context of individual patient considerations to guide the choice of an optimal approach to the management of AAAs.

The effect of endograft device on patient outcomes in endovascular repair of ruptured abdominal aortic aneurysms

Objective

Endovascular aneurysm repair for ruptured abdominal aortic aneurysm is being increasingly applied as the intervention of choice. The purpose of this study was to determine whether survival and reintervention rates after ruptured abdominal aortic aneurysm vary between endograft devices.

Methods

This cohort study identified all ruptured abdominal aortic aneurysms performed at The Ottawa Hospital from January 1999 to May 2015. Data collected included patient demographics, stability index at presentation, adherence to device instructions for use, endoleaks, reinterventions, and mortality. Kruskal–Wallis test was used to compare outcomes between groups. Mortality outcomes were assessed using Kaplan–Meier survival analysis, and multivariate Cox regression modeling.

Results

One thousand sixty endovascular aneurysm repairs were performed using nine unique devices. Ninety-six ruptured abdominal aortic aneurysms were performed using three devices: Cook Zenith ( n = 46), Medtronic Endurant ( n = 33), and Medtronic Talent ( n = 17). The percent of patients presented in unstable or extremis condition was 30.2, which did not differ between devices. Overall 30-day mortality was 18.8%, and was not statistically different between devices ( p = 0.16), although Medtronic Talent had markedly higher mortality (35.3%) than Cook Zenith (15.2%) and Medtronic Endurant (15.2%). AUI configuration was associated with increased 30-day mortality (33.3% vs. 12.1%, p = 0.02). Long-term mortality and graft-related reintervention rates at 30 days and 5 years were similar between devices. Instructions for use adherence was similar across devices, but differed between the ruptured abdominal aortic aneurysm and elective endovascular aneurysm repair cohorts (47.7% vs. 79.0%, p < 0.01). Notably, two patients who received Medtronic Talent grafts underwent open conversion >30 days post-endovascular aneurysm repair ( p = 0.01). Type 1 endoleak rates differed significantly across devices (Cook Zenith 0.0%, Medtronic Endurant 18.2%, Medtronic Talent 17.6%, p = 0.01).

Conclusion

Although we identified device-related differences in endoleak rates, there were no significant differences in reintervention rates or mortality outcomes. Favorable outcomes of Cook Zenith and Medtronic Endurant over Medtronic Talent reflect advances in endograft technology and improvements in operator experience over time. Results support selection of endograft by operator preference for ruptured abdominal aortic aneurysm.

Endovascular treatment for ruptured abdominal aortic aneurysm

BACKGROUND

An abdominal aortic aneurysm (AAA) (pathological enlargement of the aorta) is a condition that can occur as a person ages. It is most commonly seen in men older than 65 years of age. Progressive aneurysm enlargement can lead to rupture and massive internal bleeding, which is fatal unless timely repair can be achieved. Despite improvements in perioperative care, mortality remains high (approximately 50%) after conventional open surgical repair. Endovascular aneurysm repair (EVAR), a minimally invasive technique, has been shown to reduce early morbidity and mortality as compared to conventional open surgery for planned AAA repair. More recently emergency endovascular aneurysm repair (eEVAR) has been used successfully to treat ruptured abdominal aortic aneurysm (RAAA), proving that it is feasible in select patients; however, it is unclear if eEVAR will lead to significant improvements in outcomes for these patients or if indeed it can replace conventional open repair as the preferred treatment for this lethal condition. This is an update of the review first published in 2006.

OBJECTIVES

To assess the advantages and disadvantages of emergency endovascular aneurysm repair (eEVAR) in comparison with conventional open surgical repair for the treatment of ruptured abdominal aortic aneurysm (RAAA). This will be determined by comparing the effects of eEVAR and conventional open surgical repair on short-term mortality, major complication rates, aneurysm exclusion (specifically endoleaks in the eEVAR treatment group), and late complications.

SEARCH METHODS

For this update the Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register (last searched June 2016), CENTRAL (2016, Issue 5), and trials registries. We also checked reference lists of relevant publications.

SELECTION CRITERIA

Randomised controlled trials in which participants with a clinically or radiologically diagnosed RAAA were randomly allocated to eEVAR or conventional open surgical repair.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies identified for potential inclusion for eligibility. Two review authors also independently completed data extraction and quality assessment. Disagreements were resolved through discussion. We performed meta-analysis using fixed-effect models with odds ratios (ORs) and 95% confidence intervals (CIs) for dichotomous data and mean differences with 95% CIs for continuous data.

MAIN RESULTS

We included four randomised controlled trials in this review. A total of 868 participants with a clinical or radiological diagnosis of RAAA were randomised to receive either eEVAR or open surgical repair. Overall risk of bias was low, but we considered one study that performed randomisation in blocks by week and performed no allocation concealment and no blinding to be at high risk of selection bias. Another study did not adequately report random sequence generation, putting it at risk of selection bias, and two studies were underpowered. There was no clear evidence to support a difference between the two interventions for 30-day (or in-hospital) mortality (OR 0.88, 95% CI 0.66 to 1.16; moderate-quality evidence). There were a total of 44 endoleak events in 128 participants from three studies (low-quality evidence). Thirty-day complication outcomes (myocardial infarction, stroke, composite cardiac complications, renal complications, severe bowel ischaemia, spinal cord ischaemia, reoperation, amputation, and respiratory failure) were reported in between one and three studies, therefore we were unable to draw a robust conclusion. We downgraded the quality of the evidence for myocardial infarction, renal complications, and respiratory failure due to imprecision, inconsistency, and risk of bias. Odds ratios for complications outcomes were OR 2.38 (95% CI 0.34 to 16.53; 139 participants; 2 studies; low-quality evidence) for myocardial infarction; OR 1.07 (95% CI 0.21 to 5.42; 255 participants; 3 studies; low-quality evidence) for renal complications; and OR 3.62 (95% CI 0.14 to 95.78; 32 participants; 1 study; low-quality evidence) for respiratory failure. There was low-quality evidence of a reduction in bowel ischaemia in the eEVAR treatment group, but very few events were reported (OR 0.37, 95% CI 0.14 to 0.94), and we downgraded the evidence due to imprecision and risk of bias. Six-month and one-year outcomes were evaluated in three studies, but only results from a single study could be used for each outcome, which showed no clear evidence of a difference between the interventions. We rated six-month mortality evidence as of moderate quality due to imprecision (OR 0.89, 95% CI 0.40 to 1.98; 116 participants).

AUTHORS' CONCLUSIONS

The conclusions of this review are currently limited by the paucity of data. We found from the data available moderate-quality evidence suggesting there is no difference in 30-day mortality between eEVAR and open repair. Not enough information was provided for complications for us to make a well-informed conclusion, although it is possible that eEVAR is associated with a reduction in bowel ischaemia. Long-term data were lacking for both survival and late complications. More high-quality randomised controlled trials comparing eEVAR and open repair for the treatment of RAAA are needed to better understand if one method is superior to the other, or if there is no difference between the methods on relevant outcomes.

Adjusted Hospital Outcomes of Abdominal Aortic Aneurysm Surgery Reported in the Dutch Surgical Aneurysm Audit

OBJECTIVE/BACKGROUND

The Dutch Surgical Aneurysm Audit (DSAA) is mandatory for all patients with primary abdominal aortic aneurysms (AAAs) in the Netherlands. The aims are to present the observed outcomes of AAA surgery against the predicted outcomes by means of V-POSSUM (Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity). Adjusted mortality was calculated by the original and re-estimated V(physiology)-POSSUM for hospital comparisons.

METHODS

All patients operated on from January 2013 to December 2014 were included for analysis. Calibration and discrimination of V-POSSUM and V(p)-POSSUM was analysed. Mortality was benchmarked by means of the original V(p)-POSSUM formula and risk-adjusted by the re-estimated V(p)-POSSUM on the DSAA.

RESULTS

In total, 5898 patients were included for analysis: 4579 with elective AAA (EAAA) and 1319 with acute abdominal aortic aneurysm (AAAA), acute symptomatic (SAAA; n = 371) or ruptured (RAAA; n = 948). The percentage of endovascular aneurysm repair (EVAR) varied between hospitals but showed no relation to hospital volume (EAAA: p = .12; AAAA: p = .07). EAAA, SAAA, and RAAA mortality was, respectively, 1.9%, 7.5%, and 28.7%. Elective mortality was 0.9% after EVAR and 5.0% after open surgical repair versus 15.6% and 27.4%, respectively, after AAAA. V-POSSUM overestimated mortality in most EAAA risk groups (p < .01). The discriminative ability of V-POSSUM in EAAA was moderate (C-statistic: .719) and poor for V(p)-POSSUM (C-statistic: .665). V-POSSUM in AAAA repair overestimated in high risk groups, and underestimated in low risk groups (p < .01). The discriminative ability in AAAA of V-POSSUM was moderate (.713) and of V(p)-POSSUM poor (.688). Risk adjustment by the re-estimated V(p)-POSSUM did not have any effect on hospital variation in EAAA but did in AAAA.

CONCLUSION

Mortality in the DSAA was in line with the literature but is not discriminative for hospital comparisons in EAAA. Adjusting for V(p)-POSSUM, revealed no association between hospital volume and treatment or outcome. Risk adjustment for case mix by V(p)-POSSUM in patients with AAAA has been shown to be important.

Comparing the accuracy of four prognostic scoring systems in patients operated on for ruptured abdominal aortic aneurysms

OBJECTIVE

Ruptured abdominal aortic aneurysms (rAAAs) are associated with high mortality and morbidity. Several prognostic scoring systems are available for prediction of outcome, but scarcity of external validation and evaluation of predictive value has hampered widespread implementation. The aim of this study was to examine the discriminatory value of four scores in a consecutive Norwegian cohort.

METHODS

This was a retrospective study of a consecutive series of patients operated on for primary rAAA at Stavanger University Hospital from January 2000 to December 2014. The Hardman Index, Vancouver Score (VS), updated Glasgow Aneurysm Score, and Edinburgh Ruptured Aneurysm Score (ERAS) were calculated. Predictive ability in discriminating survivors and nonsurvivors was compared using receiver operating characteristics analyses and presented as area under the curve.

RESULTS

Altogether, 177 patients underwent surgery for rAAA. Mortality at 30 days was 46.3%. In receiver operating characteristics analysis, the Hardman Index had an area under the curve of 0.674 (95% confidence interval [CI], 0.588-0.753); the VS, 0.684 (95% CI, 0.610-0.752); the Glasgow Aneurysm Score, 0.680 (95% CI, 0.605-0.749); and the ERAS, 0.586 (95% CI, 0.509-0.660). VS had a significantly better fit than ERAS (P = .022).

CONCLUSIONS

The accuracy of the available scores is limited. The findings question the clinical value of such scores for decision-making.

Challenging Anatomy Predicts Mortality and Complications After Endovascular Treatment of Ruptured Abdominal Aortic Aneurysm

Purpose: To analyze the effects of aortic anatomy and endovascular aneurysm repair (EVAR) inside and outside the instructions for use (IFU) on outcomes in patients treated for ruptured abdominal aortic aneurysms (rAAA). Methods: All 112 patients (mean age 73 years; 102 men) treated with standard EVAR for rAAA between 2000 and 2012 in 3 European centers were included in the retrospective analysis. Patients were grouped based on aortic anatomy and whether EVAR was performed inside or outside the IFU. Data on complications, secondary interventions, and mortality were extracted from the patient records. Cox regression analysis was performed to assess predictors of mortality and complications; results are presented as the hazard ratio (HR) with 95% confidence interval (CI). Survival was analyzed using the Kaplan-Meier method. Results: Of the 112 patients examined, 61 (54%) were treated inside the IFU, 43 (38%) outside the IFU, and 8 patients lacked adequate preoperative computed tomography scans for determination. Median follow-up of those surviving 30 days was 2.5 years. Mortality at 30 days was 15% (95% CI 6% to 24%) inside the IFU vs 30% (95% CI 16% to 45%) outside (p=0.087). Three-year mortality estimates were 33.8% (95% CI 20.0% to 47.5%) inside the IFU vs 56% (95% CI 39.7% to 72.2%) outside (p=0.016). At 5 years, mortality was 48% (95% CI 30% to 66%) inside the IFU vs 74% (95% CI 54% to 93%) outside (p=0.015). Graft-related complications occurred in 6% (95% CI 0% to 13%) inside the IFU and 30% (95% CI 14% to 42%) outside (p=0.015). The rate of graft-related secondary interventions was 14% (95% CI 4% to 22%) inside the IFU vs 35% (95% CI 14% to 42%) outside (p=0.072). In the multivariate analysis, neck length <15 mm (HR 8.1, 95% CI 3.0 to 21.9, p<0.001) and angulation >60° (HR 3.1, 95% CI 1.0 to 9.3, p=0.045) were independent predictors of late graft-related complications. Aneurysm neck diameter >29 mm (HR 2.5, 95% CI 1.1 to 5.9, p=0.035) was an independent predictor of overall mortality. Conclusion: Long-term mortality and complications after rEVAR are associated with aneurysm anatomy. The role of adjunct endovascular techniques and the outcome of open repair in cases with challenging anatomy warrant further study.

Correlations of perioperative coagulopathy, fluid infusion and blood transfusions with survival prognosis in endovascular aortic repair for ruptured abdominal aortic aneurysm

BACKGROUND

Factors associated with survival prognosis among patients who undergo endovascular aortic repair (EVAR) for ruptured abdominal aortic aneurysms (rAAA) have not been sufficiently investigated. In the present study, we examined correlations between perioperative coagulopathy and 24-h and 30-day postoperative survival. Relationships between coagulopathy and the content of blood transfusions, volumes of crystalloid infusion and survival.

METHODS

This was a retrospective study of the medical records of all patients who underwent EVAR for rAAA at Chiba-Nishi General Hospital during the period from October 2013 to December 2015. Major coagulopathy was defined using the international normalized ratio or activated partial thromboplastin time (APTT) ratio of at least 1.5, or platelet count less than 50 × 10/l. We quantified the amounts of blood transfusions and crystalloid infusions administered from arrival to the hospital to admission to ICU following operations.

RESULTS

Coagulopathy among patients with rAAA was found to progress even after they had presented at the hospital. No statistically significant correlation between preoperative coagulopathy and mortality was found, although a significantly greater degree of postoperative coagulopathy was seen among patients who died both within 24-h and 30 days postoperatively. Among patients with postoperative coagulopathy, lesser quantities of fresh frozen plasma (FFP) compared with red cell concentrate (RCC) were used during the period from hospital arrival to postoperative ICU entry. In both groups of patients who did not survive after 24-h and 30 days, FFP was used less than RCC. Large transfusions of crystalloids administered during the periods from hospital arrival to surgery and from hospital arrival to the end of surgery were associated with postoperative incidence of major coagulopathy, death within 24-h, and death within 30 days.

CONCLUSION

Coagulopathy progressed during care in the emergency outpatient clinic and operations. Postoperative coagulopathy was associated with poorer outcomes. Smaller FFP/RCC ratios and larger volumes of crystalloid infusion were associated with development of coagulopathy and poorer prognosis of survival.

TRIAL REGISTRATION

This study is retrospectively registered in UMIN Clinical Trials Registry (Registration 19 April 2016, registered number is R000025334 UMIN000021978).

Editor's Choice - Abdominal Compartment Syndrome After Surgery for Abdominal Aortic Aneurysm: A Nationwide Population Based Study

OBJECTIVE/BACKGROUND

The understanding of abdominal compartment syndrome (ACS), and its importance for outcome, has increased over time. The aim was to investigate the incidence and clinical consequences of ACS after open (OR) and endovascular repair (EVAR) for ruptured and intact infrarenal abdominal aortic aneurysm (rAAA and iAAA, respectively).

METHODS

In 2008, ACS and decompression laparotomy (DL) were introduced as variables in the Swedish vascular registry (Swedvasc), offering an opportunity to study this complication in a prospective, population based design. Operations carried out in the period 2008-13 were analysed. Of 6,612 operations, 1,341 (20.3%) were for rAAA (72.0% OR) and 5,271 (79.7%) for iAAA (41.9% OR). In all, 3,171 (48.0%) were operated on by OR and 3,441 by EVAR. Prophylactic open abdomen (OA) treatment was validated through case records. Cross-matching with the national population registry secured valid mortality data.

RESULTS

After rAAA repair, ACS developed in 6.8% after OR versus 6.9% after EVAR (p = 1.0). All major complications were more common after ACS (p < .001). Prophylactic OA was performed in 10.7% of patients after OR. For ACS, DL was performed in 77.3% after OR and 84.6% after EVAR (p = .433). The 30 day mortality rate was 42.4% with ACS and 23.5% without ACS (p < .001); at 1 year it was 50.7% versus 31.8% (p < .001). After iAAA repair, ACS developed in 1.6% of patients after OR versus 0.5% after EVAR (p < .001). Among those with ACS, DL was performed in 68.6% after OR and in 25.0% after EVAR (p = .006). Thirty day mortality was 11.5% with ACS versus 1.8% without it (p < .001); at 1 year it was 27.5% versus 6.3% (p < .001). When ACS developed, renal failure, multiple organ failure, intestinal ischaemia, and prolonged intensive care were much more frequent (p < .001). Morbidity and mortality were similar, regardless of primary surgical technique (OR/EVAR/iAAA/rAAA).

CONCLUSION

ACS and OA were common after treatment for rAAA. ACS is a devastating complication after surgery for rAAA and iAAA, irrespective of operative technique, emphasizing the importance of prevention.

Current treatment strategies for ruptured abdominal aortic aneurysm

BACKGROUND

Ruptured abdominal aortic aneurysm (rAAA) represents one of the most challenging emergencies in surgery. Open repair (OR) is associated with relevant morbidity and mortality and has not been reduced significantly over the last decade. The introduction of endovascular aneurysm repair (EVAR) and its meanwhile common use in the treatment of rAAA has raised the demand for randomised controlled trials (RCTs) in order to resolve a potential superiority of either OR or EVAR.

PURPOSE

This review discusses the current treatment strategies in rAAA repair including diagnostics, peri-operative management and results of OR and EVAR, focussing on RCTs comparing both modalities.

RESULTS

Thirty-day mortality after OR and EVAR shows no significant difference in published RCTs. In particular with respect to OR, 30-day mortality was much lower than anticipated throughout all RCTs ranging from 18 to 37 %. EVAR for rAAA resulted in reduced in-hospital stay. Limitations of all except one RCT are low patient recruitment and exclusion of haemodynamically unstable patients.

CONCLUSIONS

OR and EVAR need to be provided for rAAA. Despite lacking evidence, EVAR is the first choice treatment in experienced high-volume vascular centres. Low mortality rates in all RCTs raise the question if aortic surgery should be centralised.

Aneurysm Shrinkage Is Compatible With Massive Endoleak in the Presence of an Aortocaval Fistula

Purpose: To present a patient with ruptured abdominal aortic aneurysm (AAA) and aortocaval fistula who was successfully treated with endovascular aneurysm repair in spite of developing a massive endoleak. Case Report: A 70-year-old man with ruptured AAA and aortocaval fistula was treated with endovascular aneurysm repair (EVAR). During 8 years of follow-up, he had massive perfusion of the aneurysm sac by retrograde flow from the inferior mesenteric artery into the caval vein through the aortocaval fistula. The aneurysm diameter decreased continuously in spite of the type II endoleak. This observation illustrates the mechanisms of sac expansion and may have therapeutic implications for complicated type II endoleaks and prevention of spinal cord ischemia in thoracic stent-grafting. Conclusion: EVAR can be applied in this rare setting because the ensuing high-flow endoleak is associated with sac shrinkage owing to depressurization by the caval shunt.