A meta-analysis of 21 178 patients undergoing open or endovascular repair of abdominal aortic aneurysm

Outcomes of Endovascular Aneurysm Repair (EVAR) Compared to Open Repair in Abdominal Aortic Aneurysm: An Umbrella Meta-Analysis

This umbrella meta-analysis aims to investigate two surgical treatments for abdominal aortic aneurysm (AAA): endovascular aneurysm repair (EVAR) and open surgery repair (OSR). Our study aims to elucidate the 30-day mortality rate, reintervention rates, and aneurysm-related mortality in EVAR versus OSR for AAA.  We conducted a comprehensive assessment of meta-analyses (n = 34 articles) comparing EVAR and OSR for AAA. We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol and considered statistical significance at P ≤ 0.05. For the 30-day mortality rate, a pooled odds ratio (pOR) of 0.59 (95% confidence interval [CI] 0.45-0.77, P = 0.0001, and I2 = 98%) indicates that EVAR was associated with a lower risk of mortality compared to OSR. For reintervention rates, a pOR of 1.33 (95% CI = 0.98-1.82, P = 0.11, and I2 = 90%). In aneurysm-related mortality, a pOR of 0.78 (95% CI = 0.63-0.97, P = 0.03, and I2 = 43%). In postoperative rupture of aneurysm, a pOR of 3.28 (95% CI = 2.16-4.98, P < 0.00001, and I2 = 50%). Furthermore, when analyzing systemic complications, only for visceral ischemia, significant results showed lower odds for EVAR, with a pOR of 0.57 (95% CI = 0.40-0.80, P = 0.001, and I2 = 0%) was found.  EVAR is better in terms of short-term mortality rate and aneurysm-related mortality. Furthermore, EVAR is still a safer procedure in elective settings, as the studies we included recruited patients for this setting. However, given the high reintervention rates and recent developments in surgical techniques and materials, more recent data and extensive research are needed.

Endovascular aortic repair with sac embolization for the prevention of type II endoleaks (the EVAR-SE study): study protocol for a randomized controlled multicentre study in Germany

BACKGROUND

Beyond a certain threshold diameter, abdominal aortic aneurysms (AAA) are to be treated by open surgical or endovascular aortic aneurysm repair (EVAR). In a quarter of patients who undergo EVAR, inversion of blood flow in the inferior mesenteric artery or lumbar arteries may lead to type II endoleak (T2EL), which is associated with complications (e.g. AAA growth, secondary type I endoleak, rupture). As secondary interventions to treat T2EL often fail and may be highly invasive, prevention of T2EL is desirable. The present study aims to assess the efficacy of sac embolization (SE) with metal coils during EVAR to prevent T2EL in patients at high risk.

METHODS

Over a 24-month recruitment period, a total of 100 patients undergoing EVAR in four vascular centres (i.e. Klinikum rechts der Isar of the Technical University of Munich, University Hospital Augsburg, University Hospital Dresden, St. Joseph's Hospital Wiesbaden) are to be included in the present study. Patients at high risk for T2EL (i.e. ≥ 5 efferent vessels covered by endograft or aneurysmal thrombus volume <40%) are randomized to one group receiving standard EVAR and another group receiving EVAR with SE. Follow-up assessments postoperatively, after 30 days, and 6 months involve contrast-enhanced ultrasound scans (CEUS) and after 12 months an additional computed tomography angiography (CTA) scan. The presence of T2EL detected by CEUS or CTA after 12 months is the primary endpoint. Secondary endpoints comprise quality of life (quantified by the SF-36 questionnaire), reintervention rate, occurrence of type I/III endoleak, aortic rupture, death, alteration of aneurysm volume, or diameter. Standardized evaluation of CTA scans happens through a core lab. The study will be terminated after the final follow-up visit of the ultimate patient.

DISCUSSION

Although preexisting studies repeatedly indicated a beneficial effect of SE on T2EL rates after EVAR, patient relevant outcomes have not been assessed until now. The present study is the first randomized controlled multicentre study to assess the impact of SE on quality of life. Further unique features include employment of easily assessable high-risk criteria, a contemporary follow-up protocol, and approval to use any commercially available coil material. Overcoming limitations of previous studies might help SE to be implemented in daily practice and to enhance patient safety.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05665101. Registered on 23 December 2022.

Brazilian Society for Angiology and Vascular Surgery guidelines on abdominal aortic aneurysm

The Brazilian Society of Angiology and Vascular Surgery, through the Guidelines Project, presents new Abdominal Aortic Aneurysm Guidelines, on the subject of care for abdominal aortic aneurysm patients. Its development prioritized descriptive guidelines, using the EMBASE, LILACS, and PubMed databases. References include randomized controlled trials, systematic reviews, meta-analyses, and cohort studies. Quality of evidence was evaluated by a pair of coordinators, aided by the RoB 2 Cochrane tool and the Newcastle Ottawa Scale forms. The subjects include juxtarenal aneurysms, infected aneurysms, and new therapeutic techniques, especially endovascular procedures. The current version of the guidelines include important recommendations for the primary topics involving diagnosis, treatment, and follow-up for abdominal aortic aneurysm patients, providing an objective guide for medical practice, based on scientific evidence and widely available throughout Brazil.

SMOC2 promoted vascular smooth muscle cell proliferation, migration, and extracellular matrix degradation by activating BMP/TGF-β1 signaling pathway

A widespread degenerative condition of the aorta, abdominal aortic aneurysm (AAA), severely endangers the health of middle-aged and elderly people. SPARC related modular calcium binding2 (SMOC2) is upregulated in the carotid arteries of rats with atherosclerotic lesions, but its function in AAA is still unknown. Therefore, the aim of this research was to evaluate the function of SMOC2 in AAA. The results showed that in the AAA tissues, SMOC2 expression was upregulated compared with healthy controls. Overexpression of SMOC2 promoted vascular smooth muscle cells (VSMCs) proliferation, migration, and extracellular matrix (ECM) degradation. In contrast, silence of SMOC2 inhibited VSMCs proliferation, migration, and ECM degradation. Overexpression of SMOC2 promoted BMP and TGF-β1 expression and silence of SMOC2 had an opposite effect. Besides, inhibition of BMP or TGF-β1 suppressed VSMCs cell proliferation, migration, and ECM degradation. Moreover, inhibition BMP or TGF-β1 reversed the promotive effects of SMOC2 overexpression on VSMCs proliferation, migration, and ECM degradation. SMOC2 may affecte the formation of AAA by upregulating BMP and TGF-β1 to regulate the proliferation, migration, and ECM degradation of VSMCs.

An Image Information-Based Objective Assessment Method of Technical Manipulation Skills for Intravascular Interventions

The clinical success of vascular interventional surgery relies heavily on a surgeon's catheter/guidewire manipulation skills and strategies. An objective and accurate assessment method plays a critical role in evaluating the surgeon's technical manipulation skill level. Most of the existing evaluation methods incorporate the use of information technology to find more objective assessment models based on various metrics. However, in these models, sensors are often attached to the surgeon's hands or to interventional devices for data collection, which constrains the surgeon's operational movements or exerts an influence on the motion trajectory of interventional devices. In this paper, an image information-based assessment method is proposed for the evaluation of the surgeon's manipulation skills without the requirement of attaching sensors to the surgeon or catheters/guidewires. Surgeons are allowed to use their natural bedside manipulation skills during the data collection process. Their manipulation features during different catheterization tasks are derived from the motion analysis of the catheter/guidewire in video sequences. Notably, data relating to the number of speed peaks, slope variations, and the number of collisions are included in the assessment. Furthermore, the contact forces, resulting from interactions between the catheter/guidewire and the vascular model, are sensed by a 6-DoF F/T sensor. A support vector machine (SVM) classification framework is developed to discriminate the surgeon's catheterization skill levels. The experimental results demonstrate that the proposed SVM-based assessment method can obtain an accuracy of 97.02% to distinguish between the expert and novice manipulations, which is higher than that of other existing research achievements. The proposed method has great potential to facilitate skill assessment and training of novice surgeons in vascular interventional surgery.

Elective Endovascular vs Open Repair for Elective Abdominal Aortic Aneurysm in Patients ≥80 years of Age: A Systematic Review and Meta-Analysis

OBJECTIVE

To provide updated, pooled evidence on clinical outcomes among octogenarians (aged ≥80 years) with abdominal aortic aneurysm (AAA) managed by elective endovascular repair, compared to conventional open repair.

METHODS

PubMed, Embase, and Scopus databases were systematically searched. Studies that were either observational or randomized controlled trials were considered for the review. Included studies were conducted in elderly subjects (≥80 years) with AAA, and clinical and mortality outcomes were compared between endovascular and open surgical repair. Those reporting on outcomes of patients with urgent repair were excluded. The primary outcomes of interest were mortality and risk of complications. The pooled effect sizes were reported as odds ratio (OR) for categorical outcomes and weighted mean difference (WMD) for continuous outcomes. STATA software was used for statistical analysis.

RESULTS

The meta-analysis included 15 studies. Compared to those undergoing open repair, patients receiving endovascular repair had significantly reduced risk of immediate post-operative mortality (OR .23, 95% CI: .20, .27), overall complication (OR .30, 95% CI: .20, .44), cardiac (OR .23, 95% CI: .16, .35), renal (OR .29, 95% CI: .18, .46), pulmonary (OR .14, 95% CI: .09, .21) and bleeding related (OR .59, 95% CI: .42, .83) complications. The risk of mortality at latest follow up (at 36 months and 60 months) was similar in the two groups. The total blood loss (ml) (WMD -1126.47, 95% CI: -1497.81, -755.13), operative time (min) (WMD -29.40, 95% CI: -56.19, -2.62), length of intensive care unit stay (days) (WMD -2.27, 95% CI: -3.43, -2.12) and overall hospital stay (days) (WMD -6.64, 95% CI: -7.60, -5.68) was significantly lower in those undergoing endovascular repair.

CONCLUSIONS

Endovascular repair appears to be better than open repair of AAA in this high-risk, frail population, with respect to short term outcomes. The benefits of reduced risk of short term mortality, complications, and better peri and post-operative outcomes may be considered when making a choice between these two surgical approaches. Randomized controlled trials are needed to provide reliable evidence on the effect of EVAR on long term survival.

Continuous transversus abdominis plane infusion via surgically inserted catheter for postoperative analgesia after abdominal aortic surgery by retroperitoneal approach: TAPCACAO study

OBJECTIVE

The purpose of our study was to evaluate the analgesic properties of continuous transversus abdominis plane (TAP) infusion with ropivacaine compared to placebo for postoperative analgesia in elective surgery of the abdominal aorta by retroperitoneal exposure.

METHOD

We conducted a prospective, single-center, randomized, double-blind study comparing a group of patients with a TAP catheter undoing ropivacaine infusion with a placebo group. Patients received a left retroperitoneal pararectal exposure for abdominal aortic surgery. A continuous infusion catheter was placed under visual control by the surgeon before closure and removed after 48 hours. All patients had postoperative patient-controlled analgesia with morphine. The primary endpoint was morphine consumption during the first 24 hours.

RESULTS

The analysis included 25 patients in the placebo group and 24 in the ropivacaine group. The average morphine consumption during the first 24 hours was significantly different, with 31 ± 16 mg in the ropivacaine group and 41 ± 17 mg in the placebo group (p = 0.019). At 48 hours, morphine consumption was still lower in the ropivacaine group (42 ± 26 mg) than in the placebo group (64 ± 25 mg) (p = 0.003). The opioid narcotic-related side effects of opioid infusion (postoperative nausea and vomiting, constipation) and length of hospital stay were similar in both populations.

CONCLUSION

Our study showed that continuous TAP block with ropivacaine via surgically inserted catheter significantly decreased morphine consumption at 24 and 48 hours after elective abdominal aortic surgery by retroperitoneal exposure.

Short-Term Re-intervention of Endovascular Abdominal Aortic Aneurysm Repair

Background and aim

Endovascular aneurysm repair (EVAR) has revolutionized the management of abdominal aortic aneurysm (AAA). The re-intervention rate following EVAR has been a subject of debate in many studies. The study aims to evaluate the short-term outcomes in terms of the early (four-year) re-intervention rate following EVAR at our centre and compare it to the average re-intervention rate of the main studies assessed by the National Institute of Health and Care Excellence (NICE).

Methods

The EVAR procedures performed over two years (2015 and 2016) were retrieved using the operation codes. The clinical portal and PACS systems were used to review the discharge summaries, clinic and multidisciplinary team (MDT) letters, as well as the scans and interventional radiology procedures to assess the patients’ adherence to follow-up and identify any re-intervention procedure done to correct underlying problems related to the EVAR performed. Patients who switched their follow-up to another hospital were contacted and interviewed about any re-intervention undergone. 

Results

A total of 108 patients underwent EVAR during the two-year study period. Twenty EVAR-related re-interventions (18.5%) were recorded, irrespective of the cause or the type of intervention. This is slightly higher than the average rate by NICE (16.89%). Type 1 endoleak represented the leading cause for re-intervention (30%). Most of the cases of re-intervention were done endovascularly (60%). Forty-five percent of the patients had a re-intervention during the first year and 35% in the third year.

Conclusion

This study shows that although our re-intervention rate following EVAR was slightly higher than the international average, EVAR is still a safe method for the repair of AAA with relatively low peri-operative morbidity and mortality. However, long-term follow-up of these patients is mandatory as re-interventions are frequently required. Nonetheless, the majority of re-interventions can be done with minimal morbidity to the patient.

Initial experience with polymer endovascular aneurysm repair using the Alto stent graft

The Alto Abdominal Stent Graft System (Endologix Inc, Irvine, Calif) is the next-generation Ovation system for polymer endovascular aneurysm repair. The most significant design change relocates the sealing ring closer to the top of the fabric, but a number of additional design changes were made. This report describes the first seven patients treated with the Alto stent graft at a single center (Auckland Hospital, Auckland, New Zealand) from August 2016 to February 2017. There was 100% procedural technical success. At 12-month follow-up, no type I or type III endoleak, stent graft migration, abdominal aortic aneurysm rupture, abdominal aortic aneurysm-related mortality, or secondary intervention was reported.

Preoperative biomarker evaluation for the prediction of cardiovascular events after major vascular surgery

OBJECTIVE

The cause of perioperative myocardial infarction (PMI) is postulated to involve hemodynamic stress or coronary plaque destabilization. We aimed to evaluate perioperative factors in patients with peripheral artery disease (PAD) undergoing major vascular surgery to determine the likely mechanisms and predictors of PMI.

METHODS

This was a prospective cohort study of 133 patients undergoing major vascular surgery including open abdominal aortic aneurysm (AAA) repair (n = 40) and major suprainguinal or infrainguinal arterial bypasses (non-AAA; n = 93). Preoperative assessment with history, physical examination, and peripheral artery tonometry was performed in addition to plasma sampling of biomarkers associated with inflammation and coronary plaque instability. The primary outcome was occurrence of a 30-day cardiovascular event (CVE; composite of PMI [troponin I elevation >99th percentile reference of ≥0.1 μg/L], stroke, or death).

RESULTS

Of 133 patients, 36 patients (27%) developed a 30-day CVE after vascular surgery, and all were PMI. Patients with 30-day CVE were older (75 ± 8 years vs 69 ± 10 years, mean ± standard deviation; P = .001), had higher prevalence of hypertension (94% vs 79%; P = .01) and preoperative beta-blocker therapy (50% vs 29%; P = .02), and had longer duration of surgery (5.1 ± 1.8 hours vs 4.0 ± 1.1 hours; P < .0001). Significant elevations in cystatin C, N-terminal pro-B-type natriuretic peptide (NT-proBNP), troponin I, high-sensitivity troponin T, matrix metalloproteinase 3, and osteoprotegerin occurred in those who developed 30-day CVE (all P < .05). Multivariate binary logistic regression identified AAA surgery and log-transformed NT-proBNP to be independent preoperative predictors of 30-day CVE (area under the receiver operating characteristic curve = 0.81).

CONCLUSIONS

In patients with peripheral artery disease undergoing major vascular surgery, the likely mechanism of PMI appears to be the hemodynamic stress related to the type and duration of surgery. NT-proBNP was a useful independent predictor of CVE and thus may serve as an important biomarker of cardiovascular fitness for surgery.

Days at Home after Surgery: An Integrated and Efficient Outcome Measure for Clinical Trials and Quality Assurance

BACKGROUND

Surgical audit, sometimes including public reporting, is an important foundation of high quality health care. We aimed to assess the validity of a novel outcome metric, days at home up to 30 days after surgery, as a surgical outcome measure in clinical trials and quality assurance.

METHODS

This was a multicentre, registry-based cohort study. We used prospectively collected hospital and national healthcare registry data obtained from patients aged 18 years or older undergoing a broad range of surgeries in Sweden over a 10-year period. The association between days at home up to 30 days after surgery and patient (older age, poorer physical status, comorbidity) and surgical (elective or non-elective, complexity, duration) risk factors, process of care outcomes (re-admissions, discharge destination), clinical outcomes (major complications, 30-day mortality) and death up to 1 year after surgery were measured.

FINDINGS

From January, 2005, to December, 2014, we obtained demographic and perioperative data on 636,885 patients from 21 Swedish hospitals. Mortality at 30 days and one year was 1.8% and 7.3%, respectively. The median (IQR) days at home up to 30 days after surgery was 27 (23-29), being significantly lower among high-risk patients, those recovering from more complex surgical procedures, and suffering serious postoperative complications (all p < 0.0001). Patients with 8 days or less at home up to 30 days after surgery had a nearly 7-fold higher risk of death up to 1 year postoperatively when compared with those with 29 or 30 days at home (adjusted HR 6.78 [95% CI: 6.44-7.13]).

INTERPRETATION

Days at home up to 30 days after surgery is a valid, easy to measure patient-centred outcome metric. It is highly sensitive to changes in surgical risk and impact of complications, and has prognostic importance; it is therefore a valuable endpoint for perioperative clinical trials and quality assurance.

FUNDING

Swedish National Research Council Medicine and Stockholm County Council ALF-project grant (LE), and the Australian National Health and Medical Research Council (PM).

Global Post-Market Clinical Follow-up of the Treovance Stent-Graft for Endovascular Aneurysm Repair: One-Year Results From the RATIONALE Registry

PURPOSE:

To evaluate the safety and performance of the Treovance stent-graft.

METHODS:

The global, multicenter RATIONALE registry ( ClinicalTrials.gov; identifier NCT03449875) prospectively enrolled 202 patients (mean age 73.0±7.8 years; 187 men) with abdominal aortic aneurysms (AAA) suitable for endovascular aneurysm repair (EVAR) using the Treovance. The composite primary safety endpoint was site-reported all-cause mortality and major morbidity. The primary efficacy outcome was clinical success. Further outcomes evaluated included technical success; stent-graft migration, patency, and integrity; endoleak; and aneurysm size changes.

RESULTS:

Technical success was 96% (194/202); 8 patients had unresolved type I endoleaks at the end of the procedure. There was no 30-day mortality and 1% major morbidity (1 myocardial infarction and 1 bowel ischemia). Clinical success at 1 year was confirmed in 194 (96%) patients; 6 of 8 patients had new/persistent endoleaks and 2 had aneurysm expansion without identified endoleak. A total of 8 (4%) reinterventions were required during the mean 13.7±3.1 months of follow-up (median 12.8). At 1 year, the Kaplan-Meier estimate for freedom from reintervention was 95.6% (95% CI 91.4% to 97.8%). Other estimates were 95.5% (95% CI 91.7% to 97.6%) for freedom from endoleak type I/III and 97.4% (95% CI 94.2% to 98.9%) for freedom from aneurysm expansion. Thirteen (6.4%) patients died; no death was aneurysm related.

CONCLUSION:

The RATIONALE registry showed favorable safety and clinical performance of the Treovance stent-graft for the treatment of infrarenal AAAs in a real-world setting.

Marfan syndrome combined with huge abdominal aortic aneurysm size of 20 × 11 cm: A case report of surgical approach

RATIONALE

Abdominal aortic aneurysm is one of the most common aneurisms. Patients presenting with secondary back pain should be given prompt medical attention. Herein, a rare case of a giant abdominal aortic aneurysm that was successfully treated with surgery is described.

PATIENT CONCERNS

A 33-year-old Chinese male suffered from Marfan syndrome combined with giant abdominal aortic aneurysm, and presented with back pain, fever, nausea, vomiting, abdominal distention, and constipation. After undergoing numerous tests, the patient underwent an abdominal aortic aneurysm resection coupled with artificial graft bypass. The patient's recovery was smooth, and he was discharged 14 days after the operation in stable condition.

DIAGNOSIS

Abdominal aortic aneurysm.

INTERVENTIONS

The patient underwent a surgery involving mass resection and artificial graft bypass.

OUTCOME

The patient was discharged 14 days after surgery in stable condition.

LESSONS

Giant abdominal aortic aneurysms are rarely seen, and aneurysmectomy associated with prosthetic vascular graft repair is an effective and standard treatment for such aneurysms.

TIMP‑3 suppresses the proliferation and migration of SMCs from the aortic neck of atherosclerotic AAA in rabbits, via decreased MMP‑2 and MMP‑9 activity, and reduced TNF‑α expression

The present study investigated the role of tissue inhibitor of matrix metalloproteinase‑3 (TIMP‑3) in regulating the proliferation, migration, apoptosis and activity of matrix metalloproteinase (MMP)‑2 and ‑9, during the development of an atherosclerotic abdominal artery aneurysm (AAA). Experiments were conducted using rabbit AAA neck (NA) smooth muscle cells (SMCs), to investigate the potential for TIMP‑3 to be used as a novel stent coating in preventing aortic dilation adjacent to the AAA. The atherosclerotic AAA model was induced in New Zealand white rabbits via a 6‑week high‑cholesterol diet, followed by incubation of the targeted aortic region with elastase. SMCs were isolated from the aorta adjacent to the aneurysm 30 days after AAA model induction, and stimulated with 3, 10, 30 or 100 ng/ml TIMP‑3. Cell proliferation was investigated using Cell Counting Kit‑8 reagent, migration was examined using a Boyden chamber assay and apoptotic rate was analyzed using the Annexin V‑fluorescein isothiocyanate Apoptosis Detection kit. Gelatin zymography and ELISA were used to measure the activity of MMP‑2 and MMP‑9, and the expression of tumor necrosis factor‑α (TNF‑α), respectively. Analysis of cell proliferation indicated that 10, 30 and 100 ng/ml TIMP‑3 reduced cell viability. Cell migration was decreased by 10, 30 and 100 ng/ml TIMP‑3. MMP‑2 activity was inhibited by 10, 30 and 100 ng/ml TIMP‑3, and MMP‑9 activity was suppressed by 30 and 100 ng/ml TIMP‑3. The protein levels of secreted TNF‑α were reduced by 10, 30 and 100 ng/ml TIMP‑3. The present study demonstrated the ability of 30 and 100 ng/ml TIMP‑3 to attenuate migration and proliferation, and to inhibit the activity of MMP‑2, MMP‑9 and TNF‑α secretion of NA SMCs. In conclusion, TIMP‑3 may be considered a potential therapeutic drug for use in a novel drug‑eluting stent, to attenuate the progressive dilation of the aortic NA.

Epidemiology and contemporary management of abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) is most commonly defined as a maximal diameter of the abdominal aorta in excess of 3 cm in either anterior-posterior or transverse planes or, alternatively, as a focal dilation ≥ 1.5 times the diameter of the normal adjacent arterial segment. Risk factors for the development of AAA include age > 60, tobacco use, male gender, Caucasian race, and family history of AAA. Aneurysm growth and rupture risk appear to be associated with persistent tobacco use, female gender, and chronic pulmonary disease. The majority of AAAs are asymptomatic and detected incidentally on various imaging studies, including abdominal ultrasound, and computed tomographic angiography. Symptoms associated with AAA may include abdominal or back pain, thromboembolization, atheroembolization, aortic rupture, or development of an arteriovenous or aortoenteric fistula. The Screening Abdominal Aortic Aneurysms Efficiently (SAAAVE) Act provides coverage for a one-time screening abdominal ultrasound at age 65 for men who have smoked at least 100 cigarettes and women who have family history of AAA disease. Medical management is recommended for asymptomatic patients with AAAs < 5 cm in diameter and focuses on modifiable risk factors, including smoking cessation and blood pressure control. Primary indications for intervention in patients with AAA include development of symptoms, rupture, rapid aneurysm growth (> 5 mm/6 months), or presence of a fusiform aneurysm with maximum diameter of 5.5 cm or greater. Intervention for AAA includes conventional open surgical repair and endovascular aortic stent graft repair.

A retrospective observational cohort study investigating the association between acute kidney injury and all-cause mortality among patients undergoing endovascular repair of abdominal aortic aneurysms

BACKGROUND

Acute kidney injury (AKI) has been found to be associated with short- and long-term mortality and morbidity in various clinical settings. However, it is unknown whether AKI after endovascular repair of abdominal aortic aneurysms (EVAR) is associated with postoperative mortality.

METHODS

This observational study analyzed patients who underwent EVAR. The primary outcome was all-cause mortality. The outcomes of patients with and without postoperative AKI were compared using the Kaplan-Meier method and log-rank test. Factors with P < 0.05 on the univariate analysis were entered into the multivariate Cox regression model. Predictors of AKI were also determined using Cox univariate and multivariate analysis. The identified predictors of AKI were excluded from multivariate analysis for all-cause mortality because these factors could intermediate outcome.

RESULTS

There were 490 eligible patients. After a follow-up of 28.3 (16.8) months [mean (standard deviation)], 62 patients (12.7%) died. AKI occurred in 59 patients (12.0%). AKI was found by the log-rank test to be associated with a significant increase of all-cause mortality (P < 0.001). Preoperative estimated glomerular filtration rate, preoperative peripheral vascular disease, and emergency surgery were found to be independent predictors of AKI and these variables were excluded from the main analysis. Multivariate analysis showed AKI [hazard ratio (HR) = 1.19, 95% confidence interval (CI) 1.01-3.60, P = 0.045] and transfusion (HR = 1.05, 95% CI 1.01-1.09, P = 0.011) were independent predictors of mortality.

CONCLUSIONS

In the present study, AKI and transfusion were associated with significant increases in all-cause mortality after EVAR.

The incidence, risk factors and in-hospital mortality of acute kidney injury in patients after abdominal aortic aneurysm repair surgery

Background

Acute kidney injury (AKI) is a severe complication associated with abdominal aortic aneurysm (AAA) repair. In this study, we evaluated the incidence, risk factors and in-hospital mortality of AKI in patients after the AAA repair surgery.

Methods

A total of 314 Chinese AAA patients who underwent endovascular aneurysm repair (EVAR) or open aneurysm repair (OPEN) were enrolled in this study. AKI was diagnosed according to the 2012 KDIGO criteria. Logistic regression modeling was used to explore risk factors of AKI, while risk factors associated with in-hospital mortality in AKI patients were investigated using Cox proportional hazards model and Kaplan-Meier analysis, respectively. Multicollinearity analysis was performed to identify the collinearity between the variables before logistic regression analysis and Cox proportional hazards analysis.

Results

Among 314 patients, 94 (29.9%) developed AKI after AAA repair surgery. Severity of AKI and ruptured AAA were independently associated with an increase in in-hospital mortality in AKI patients after AAA repair. Kaplan-Meier analysis identified severity of AKI as being negatively associated with hospital survival in AKI patients. Risk factors associated with AKI included cardiovascular disease (OR 3.169, 95% confidence interval (CI) 1.538 to 6.527, P = 0.002), decreased eGFR (OR 0.965, 95%CI 0.954 to 0.977, P < 0.001), ruptured AAA (OR 2.717, 95%CI 1.320 to 5.592, P = 0.007), renal artery involvement (OR 2.903, 95%CI 1.219 to 6.912, P = 0.016) and OPEN (OR 2.094, 95%CI 1.048 to 4.183, P = 0.036). Further subgroup analysis identified OPEN as an important risk factor of AKI in ruptured AAA patients but not in ruptured AAA patients. The incidence of AKI was significantly lower in EVAR than in OPEN (27.1% vs. 42.8%) and, similarly lower in nonruptured AAA than in ruptured AAA (26.2% vs. 48.1%).

Conclusion

One-third of AAA patients developed AKI after repair surgery. Severity of AKI was associated with reduced survival rate in AAA patients who developed postoperative AKI. Decreased preoperative creatinine clearance, cardiovascular disease, ruptured AAA and OPEN were independent risk factors for postoperative AKI in all 314 AAA patients. Although a lower rate of incident AKI was observed in EVAR compared with OPEN, subgroup analysis of ruptured AAA versus nonruptured AAA showed that EVAR was an independent protective factor for AKI only in ruptured AAA patients but not in nonruptured AAA patients.

Pre-operative Simulation of the Appropriate C-arm Position Using Computed Tomography Post-processing Software Reduces Radiation and Contrast Medium Exposure During EVAR Procedures

OBJECTIVE/BACKGROUND

The aim was to evaluate the feasibility and efficacy of a new method for pre-operative calculation of an appropriate C-arm position for iliac bifurcation visualisation during endovascular aortic repair (EVAR) procedures by using three dimensional computed tomography angiography (CTA) post-processing software.

METHODS

Post-processing software was used to simulate C-arm angulations in two dimensions (oblique, cranial/caudal) for appropriate visualisation of distal landing zones at the iliac bifurcation during EVAR. Retrospectively, 27 consecutive EVAR patients (25 men, mean ± SD age 73 ± 7 years) were identified; one group of patients (NEW; n = 12 [23 iliac bifurcations]) was compared after implementation of the new method with a group of patients who received a historic method (OLD; n = 15 [23 iliac bifurcations]), treated with EVAR before the method was applied.

RESULTS

In the OLD group, a median of 2.0 (interquartile range [IQR] 1-3) digital subtraction angiography runs were needed per iliac bifurcation versus 1.0 (IQR 1-1) runs in the NEW group (p = .007). The median dose area products per iliac bifurcation were 11951 mGy*cm² (IQR 7308-16663 mGy*cm²) for the NEW, and 39394 mGy*cm² (IQR 19066-53702 mGy*cm²) for the OLD group, respectively (p = .001). The median volume of contrast per iliac bifurcation was 13.0 mL (IQR: 13-13 mL) in the NEW and 26 mL (IQR 13-39 mL) in the OLD group (p = .007).

CONCLUSION

Pre-operative simulation of the appropriate C-arm angulation in two dimensions using dedicated computed tomography angiography post-processing software is feasible and significantly reduces radiation and contrast medium exposure.

Contrast Medium Induced Nephropathy after Endovascular Stent Graft Placement: An Examination of Its Prevalence and Risk Factors

Endovascular stent graft placement has become a major treatment for thoracic and abdominal aneurysms. While endovascular therapy is less invasive than open surgery, it involves the use of a contrast medium. Contrast media can cause renal impairment, a condition termed as contrast-induced nephropathy (CIN). This study sought to evaluate the incidence and risk factors of CIN following endovascular stent graft placement for aortic aneurysm repair. The study included 167 consecutive patients who underwent endovascular stent graft placement in our hospital from October 2013 to June 2014. CIN was diagnosed using the European Society of Urogenital Radiology criteria. Patients with and without CIN were compared. Chi-squared tests, t-tests, and multivariate logistic regression analyses were performed. Thirteen patients (7.8%) developed CIN. Left ventricular dysfunction and intraoperative blood transfusion were significantly more frequent in the CIN group (P = 0.017 and P = 0.032, resp.). Multivariate analysis showed that left ventricular dysfunction had the strongest influence on CIN development (odds ratio 9.34, P = 0.018, and 95% CI = 1.46–59.7). Patients with CIN also experienced longer ICU and hospital stays. Measures to improve renal perfusion flow should be considered for patients with left ventricular dysfunction who are undergoing endovascular stent graft placement.

[Endovascular versus conventional vascular surgery - old-fashioned thinking? Part 1: interventions on the aorta]

Endovascular therapy has widely replaced conventional open vascular surgical reconstruction. For this reason both techniques were widely considered to be competing approaches. Evidence-based data from randomized prospective trials, meta-analyses and clinical registries, however, demonstrated that both techniques should be used to complement each other. It became increasingly more evident that the use of either procedure depends on the underlying disease and the anatomical conditions, whereby a combination of both (hybrid approach) may be the preferred option in certain situations. This review focuses on the treatment of complicated acute type B aortic dissection, descending thoracic aortic aneurysms, thoracoabdominal aortic aneurysms as well as asymptomatic and ruptured abdominal aortic aneurysms.

Renal Function is the Main Predictor of Acute Kidney Injury after Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

Postoperative acute kidney injury (AKI) may occur in up to 18% of elective endovascular abdominal aortic aneurysm repair (EVAR) and has been associated with poor outcome; however, it is not clear which patients are at highest risk, to target renoprotection effectively. We sought to determine the predictive factors of AKI after elective EVAR.

METHODS

Overall, 947 patients undergoing elective EVAR between January 2004 and December 2014 were analyzed, using prospectively collected data. Postoperative AKI was defined by serum creatinine change within 48 hr, as per the Kidney Disease Improving Global Outcomes guidelines. Cardiovascular and kidney-disease risk factors were entered in univariate and multivariate analyses to assess influence on AKI development.

RESULTS

Overall, 167 (17.6%) patients developed AKI but only 2 patients required dialysis perioperatively. At multivariate analysis, adjusted for established AKI-risk factors and parameters that differed between groups at baseline, preoperative estimated glomerular filtration rate (eGFR; as per the chronic kidney disease epidemiology [CKD] formula); odds ratio (OR): 1.02 (per unit decrease); 95% confidence interval (CI): 1.003-1.041; P = 0.025; and chronic kidney disease (CKD) stage > 2 (OR: 1.28; 95% CI: 1.249-2.531, P = 0.001) were associated with development of AKI.

CONCLUSIONS

AKI was common after elective infrarenal EVAR and preoperative renal function appears to be the main factor associated with AKI. Patients with a low eGFR need to be targeted with more aggressive renal protection.

Long-Term Renal Function after Endovascular Aneurysm Repair

BACKGROUND AND OBJECTIVES

Endovascular repair (EVAR) is a common treatment for abdominal aortic aneurysm (AAA). However, its long-term effects on renal function remain unclear. We aimed to assess long-term renal dysfunction after EVAR using a contemporary estimate of GFR and to compare long-term renal outcomes in patients after EVAR with open aneurysm repair (OAR) and in patients without an AAA.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

We performed a nested case-matched analysis of 726 patients (using a prospectively maintained database for repairs that took place between January 2000 and May 2010 in a tertiary center): 121 patients undergoing OAR (with data at baseline and 5 years postrepair) were case matched (age, sex, smoking, diabetes, baseline eGFR) to patients undergoing suprarenal and infrarenal fixation EVAR (242 in each group) and to 121 patients undergoing carotid endarterectomy (CEA) without AAA. Changes in eGFR were compared (1 and 5 years).

RESULTS

The OAR patients lost an average of 7.4 ml/min per 1.73 m2 at 5 years (95% confidence interval [95% CI], 4.8 to 10.6), compared with 8.2 ml/min per 1.73 m2 (95% CI, 6.5 to 10.8; P<0.001) for infrarenal-fixation EVAR, 16.9 ml/min per 1.73 m2 (95% CI, 13.0 to 21.9, P<0.001) for suprarenal-fixation EVAR, and 5.4 ml/min per 1.73 m2 (95% CI, 1.7 to 7.5; P<0.001) for CEA. The decrease in eGFR was steeper during the first postoperative year, with each group losing -2.2 ml/min per 1.73 m2 (infrarenal-fixation EVAR), -10.7 ml/min per 1.73 m2 (suprarenal-fixation EVAR), and -4.6 ml/min per 1.73 m2 (OAR), compared with -1.9 ml/min per 1.73 m2 for CEA.

CONCLUSIONS

Elective EVAR is associated with a significant decline in eGFR after 5 years, which is steeper in the first postoperative year and more pronounced compared with a similar population with atherosclerotic disease.

Impact of Fenestrated Endovascular Abdominal Aortic Aneurysm Repair on Renal Function

Purpose: To investigate the impact of fenestrated endovascular aneurysm repair (fEVAR) on renal function perioperatively and at midterm. Methods: A case-controlled study was performed involving 58 patients (mean age 75±7 years; 51 men) who underwent elective fEVAR for a juxtarenal or short-necked abdominal aortic aneurysm (AAA) matched on age, sex, smoking, diabetes, and baseline estimated glomerular filtration rate (eGFR) with a contemporaneous group undergoing open aneurysm repair (OAR) for the same indications. Perioperative incidence of acute kidney injury (AKI) and levels of eGFR at 30 days and 1 year were compared. A systematic literature review was performed to identify studies that had used eGFR as renal outcome after fEVAR; the pooled data were meta-analyzed using an eGFR drop >30% at 1 month and the latest follow-up as endpoints. Results are reported as the pooled proportion and 95% confidence interval (CI). Results: The incidence of AKI after fEVAR was 28% compared to 10% after OAR (p=0.03). Following fEVAR, the mean eGFR dropped from 78±8 to 74±9 mL/min/1.73 m2 at 30 days compared to a change from 79±8 to 80±16 mL/min/1.73 m2 after OAR (p<0.01). However, the absolute drop in eGFR between fEVAR and OAR at 1 year was similar (7 mL/min/1.73 m2; p=0.53); 7% of the fEVAR patients had an eGFR drop >30% at that point compared with none for OAR (p=0.12). The systematic literature review identified eGFR outcomes for 193 fEVAR patients. Combining these patients with the 58 from our cohort study, the pooled proportions of eGFR drop >30% were 20% (95% CI 9% to 39%) at 30 days and 8% (95% CI 0.5% to 13%) at the end of follow-up. Conclusion: fEVAR has a significant perioperative impact on renal function, but 1-year results are similar to OAR. fEVAR patients may benefit from targeted AKI prevention strategies that need to be assessed in relevant studies.

Performance of the Aorfix endograft in severely angulated proximal necks in the PYTHAGORAS United States clinical trial

OBJECTIVE

This study compared the performance of the Aorfix endograft (Lombard Medical, Oxfordshire, United Kingdom) in standard (<60°), highly angled (60°-90°), and severely angled (>90°) aortic necks in the PYTHAGORAS study and evaluated changes in neck morphology over time.

METHODS

PYTHAGORAS is a prospective nonrandomized clinical trial of the Aorfix endograft. We divided the endovascular aneurysm repair (EVAR) cohort into groups by standard, high, and severe neck angle. The primary control group was patients concurrently undergoing open repair. Mortality at 30 days, 1 year, and 2 years and 30-day freedom from Society for Vascular Surgery major adverse events for the EVAR groups was compared with the open control. Aneurysm sac change, type I and III endoleaks, graft migration, and the reintervention rate at 1 and 2 years was compared between the standard, highly, and severely angled populations. The relative risk of graft complications with a neck diameter increase >10% was also calculated. At predetermined anatomic points, the effect of oversizing on aortic diameter was evaluated by calculating oversize percentage ([1 - outer aortic diameter measured at a given time/stent graft diameter] × 100%) preoperatively and at 3 years. In addition, the average oversizing percentage at 30 days and annually at 1 to 5 years was compared with the preoperative oversizing percentage. Finally, complication rates with ≥30% vs <30% planned oversizing were compared.

RESULTS

The adverse event rate was lower for every EVAR group than the open control. In addition, the mortality rates at 30 days, 1 year, and 2 years were similar between the standard-angle (1.5%, 3.0%, 4.5%), high-angle (0.9%, 7.3%, 13.8%), and severe-angle (4.8%, 9.5%, 14.3%) EVAR groups and the open control groups (1.3, 6.6%, 10.5%). At 1 and 2 years, there was no difference in graft complications among the EVAR groups. However, with neck dilatation of >10% at 5 mm above the proximal renal and 1 mm below the distal renal, there was an increased risk of graft migration (relative risk, 4.38 [P = .01] and 4.33 [P = .002], respectively). For all predetermined anatomic points, the oversizing percentage decreased over time. The rate of oversize percentage decrease was faster at more distal aortic locations, reaching <10% at 30 days 15 mm below the renal, at 2 years 7 mm below the renal, and at 5 years 1 mm below the renal (P < .001 for all). Half the oversize percentage achieved at the index procedure remained at 3 years (Pearson correlation coefficient = 0.5). However, there was no difference in complications between the ≥30% and <30% planned oversize groups.

CONCLUSIONS

The Aorfix endograft has performed well in excluding aneurysms with standard and highly angled aortic neck anatomy.

Is Endovascular Aneurysm Repair a Relative Contraindication for Patients with Preoperative Renal Dysfunction?

Whether endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) is a relative contraindication in patients with preoperative renal dysfunction (Pre-RD), remains controversial because the contrast medium may induce nephrotoxicity. In this study 1658 patients were treated at ten Japanese medical centers between January 2005 and March 2011 (Open surgery (OS) vs. EVAR: n = 1270 vs. n = 388). They were retrospectively analyzed. Multiple logistic regression analysis (MLRA) with pre- and intra-operative variables was applied to all patients. The endpoints induced onset of new dialysis and postoperative renal dysfunction (Post-RD), were defined as a 50% decrease or more from the preoperative estimated glomerular filtration rate (eGFR) level.

RESULTS

Early mortality, Post-RD, incidence of new dialysis in all patients were 1.6% (OS: EVAR = 1.9%:0.8%), 6% (OS: EVAR = 8%:2.3%) and 1.4% (OS: EVAR = 1.5%:1.0%) respectively. MLRA identified operation time, clamp of renal artery as risk factors for Post-RD, and operation time and Pre-eGFR level as risk factors for new dialysis.

CONCLUSION

Although Post-RD was more frequently observed in the OS group, MLRA showed that the choice of OS or EVAR was not a risk factor for Post-RD and new dialysis. It was strongly suggested that using contrast medium during EVAR is not a contraindication to AAA repair in patients with Pre-RD. (This article is a translation of J Jpn Coll Angiol 2014; 54: 13-18.).

Long-term outcomes and factors influencing late survival following elective abdominal aortic aneurysm repair: A 24-year experience

Background

Abdominal aortic aneurysms can be either treated by an open abdominal aortic aneurysm repair or an endovascular repair. Comparing clinical predictors of outcomes and those which influence survival rates in the long term is important in determining the choice of treatment offered and the decision-making process with patients.

Aims

To determine the influence of pre-existing clinical predictors and perioperative determinants on late survival of elective open abdominal aortic aneurysm repair and endovascular repair at a tertiary hospital.

Methods

Consecutive patients undergoing elective abdominal aortic aneurysm repair from 1990 to 2013 were included. Data were collected from a prospectively acquired database and death data were gathered from the Queensland state death registry. Pre-existing risks and perioperative factors were assessed independently. Kaplan–Meier and Cox regression modeling were performed.

Results

During the study period, 1340 abdominal aortic aneurysms were repaired electively, of which 982 were open abdominal aortic aneurysm repair. The average age was 72.4 years old and 81.7% were males. The cumulative percentage survival rates for open abdominal aortic aneurysms repair at 5, 10, 15 and 20 years were 79, 49, 31 and 22, respectively. The corresponding 5-, 10- and 15-year survival rates for endovascular repair were not significantly different at 75, 49 and 33%, respectively (P = 0.75). Predictors of reduced survival were advanced age, American Society of Anaesthesiology scores, chronic obstructive pulmonary disease, renal impairment, bifurcated grafts, peripheral vascular disease and congestive heart failure.

Conclusions

Open repair offers a good long-term treatment option for patients with an abdominal aortic aneurysm and in our experience there is no significant difference in late survival between open abdominal aortic aneurysms repair and endovascular repair. Consideration of the factors identified in this study that predict reduced long-term survival for open abdominal aortic aneurysms repair and endovascular repair should be considered when deciding repair of abdominal aortic aneurysm.

Active Proximal Sealing in the Endovascular Repair of Abdominal Aortic Aneurysms

Purpose: To investigate the performance of a new device that uses the STRATA polytetrafluoroethylene graft material and a mechanism that provides active proximal sealing in order to prevent type Ia endoleak during endovascular aneurysm repair (EVAR). Methods: Between April 2013 and July 2014, 21 consecutive patients (all men; median age 71 years, range 60–84 years) with abdominal aortic aneurysm (median diameter 5.9 cm, range 4.9–7.8 cm) and suitable anatomy were offered elective EVAR using the AFX endograft. These patients had an irregular, conical, tapered, or bulging proximal neck, for which this specific device was considered appropriate. Aneurysm exclusion and incidence of type Ia endoleak were the primary outcomes; secondary outcomes included mortality, morbidity, migration, and other graft-related complications. Results: Primary technical success was 90%; 2 intraoperative type Ia endoleaks due to low endograft deployment were treated with additional proximal cuffs. During a median follow-up of 10 months (range 2–15 months), no type I endoleak was observed. One type II endoleak was encountered, with no associated sac enlargement. There was no stent-graft migration or any other device-related complication. One patient had a nonfatal myocardial infarction and another developed renal failure requiring transient dialysis. No deaths occurred. Conclusion: In this early experience, this newly available device appears to be safe and efficient in providing seal along irregularly shaped necks over the short term.

Incidence of Acute Kidney Injury (AKI) after Endovascular Abdominal Aortic Aneurysm Repair (EVAR) and Impact on Outcome

BACKGROUND

Acute kidney injury (AKI) is an important post-operative complication that may impact on mortality, morbidity, and cost. The incidence after endovascular aneurysm repair (EVAR) remains unknown, as the current literature has not employed consistent definitions. The aim of this study is to assess the incidence of AKI after elective EVAR and examine the impact of AKI on mortality and cardiovascular morbidity using the current universally accepted definitions.

METHODS

This was a cohort study using prospectively collected data, including consecutive patients undergoing elective EVAR for an infrarenal abdominal aortic aneurysm (AAA). Those with end stage renal failure were excluded. The primary endpoint was incidence of AKI as per the "Acute Kidney Injury Network" (AKIN), and "Kidney Disease Improving Global Outcomes" (KDIGO) criteria. Secondary endpoints included AKI stage, drop in estimated glomerular filtration rate (eGFR), and mortality and cardiovascular morbidity.

RESULTS

149 patients were included (16 females, 11%; mean age: 69 ± 8 years; mean AAA diameter: 6.0 ± 1.1 cm), 28 (18.8%) of whom developed AKI (26 patients classified as stage 1 and 2 as stage 2). Within 48 hours, those with AKI dropped their eGFR from 61 ± 20 mL/kg/1.73 m(2) to 51 ± 20 units (p < .001), and those without from 75 ± 9 to 74 ± 10 units (p < .001). None required dialysis during a 33 ± 11 month follow up. Development of AKI was associated with mortality (HR 0.035, 95% CI: 0.005 to 0.240, p < .001) and cardiovascular morbidity (HR: 0.021, 95% CI: 0.004 to 0.11, p < .001) on adjusted regression analysis.

CONCLUSIONS

The incidence of AKI after EVAR is significant and is independently associated with medium-term mortality and morbidity.

Designation as "unfit for open repair" is associated with poor outcomes after endovascular aortic aneurysm repair

BACKGROUND

Endovascular aortic aneurysm repair (EVAR) is often offered to patients with abdominal aortic aneurysms (AAAs) considered preoperatively to be unfit for open AAA repair (oAAA). This study describes the short- and long-term outcomes of patients undergoing EVAR with AAAs <6.5 cm who are considered unfit for oAAA.

METHODS AND RESULTS

We analyzed elective EVARs for AAAs <6.5 cm diameter in the Vascular Study Group of New England (2003-2011). Patients were designated as fit or unfit for oAAA by the treating surgeon. End points included in-hospital major adverse events and long-term mortality. We identified patient characteristics associated with being unfit for open repair and predictors of survival using multivariable analyses. Of 1653 EVARs, 309 (18.7%) patients were deemed unfit for oAAA. These patients were more likely to have advanced age, cardiac disease, chronic obstructive pulmonary disease, and larger aneurysms at the time of repair (54 versus 56 mm, P=0.001). Patients unfit for oAAA had higher rates of cardiac (7.8% versus 3.1%, P<0.01) and pulmonary (3.6 versus 1.6, P<0.01) complications and worse survival rates at 5 years (61% versus 80%; log rank P<0.01) compared with those deemed fit for oAAA. Finally, patients designated as unfit for oAAA had worse survival, even adjusting for patient characteristics and aneurysm size (hazard ratio, 1.6; 95% confidence interval, 1.2-2.2; P<0.01).

CONCLUSIONS

In patients with AAAs <6.5 cm, designation by the operating surgeon as unfit for oAAA provides insight into both short- and long-term efficacy of EVAR. Patients unable to tolerate oAAA may not benefit from EVAR unless their risk of AAA rupture is very high.

Open versus Endovascular Repair of Abdominal Aortic Aneurysm in the Elective and Emergent Setting in a Pooled Population of 37,781 Patients: A Systematic Review and Meta-Analysis

Background. We evaluated the incidence of mortality and myocardial infarction (MI) in endovascular repair (EVAR) as compared to open aneurysm repair (OAR) in both elective and ruptured abdominal aortic aneurysm (AAA ) setting. Methods. We analyzed the rates of 30-day mortality, 30-day MI, and hospital length of stay (LOS) based on comparative observation and randomized control trials involving EVAR and OAR. Results. 41 trials compared EVAR to OAR with a total pooled population of 37,781 patients. Analysis of elective and ruptured AAA repair favored EVAR with respect to 30-day mortality with a pooled odds ratio of 0.19 (95% CI 0.17–0.20; I² = 88.9%; P < 0.001). There were a total of 1,835 30-day MI events reported in the EVAR group as compared to 2,483 events in the OAR group. The pooled odds ratio for elective AAA was 0.74 (95% CI 0.58–0.96; P = 0.02) in favor of EVAR. The average LOS was reduced by 296.75 hrs (95% CI 156.68–436.82 hrs; P < 0.001) in the EVAR population. Conclusions. EVAR has lower rates of 30-day mortality, 30-day MI, and LOS in both elective and ruptured AAA repair.

Endovascular aneurysm repair in emergent ruptured abdominal aortic aneurysm with a 'real' hostile neck and severely tortuous iliac artery of an elderly patient

Background

Endovascular aneurysm repair (EVAR) has been a revolutionary development in the treatment of abdominal aortic aneurysms (AAAs). Meanwhile, unfavorable anatomy of the aneurysm has always been a challenge to vascular surgeons, and the application of EVAR in emergent and elderly patients are still in dispute.

Case presentation

A 79-year-old woman presented as an emergency of abdominal pain with acute hypotension, heart rate elevation and a rapid decrease of hemoglobin. Emergent computed tomographic angiography (CTA) showed a ruptured AAA (rAAA) extending from below the opening of bilateral renal arteries down to the celiac artery and elongated to both common iliac arteries. The hostile neck and severely tortuous iliac artery made the following procedure a great challenge. An emergent endovascular approach was performed in which an excluder aortic main body was deployed below the origin of the bilateral renal arteries covering the ruptured aortic segment. Two iliac legs were placed superior to the opening of the right hypogastric respectively. In order to avoid the type Ib endoleak, we tried to deploy another cuff above the bifurcation of the iliac artery. However, the severely tortuous right iliac artery made this procedure extremely difficult, and a balloon-assisted technique was used in order to keep the stiff wire stable. Another iliac leg was placed above the bifurcation of the left iliac artery. The following angiography showed a severe Ia endoleak in the proximal neck and therefore, a cuff was deployed distal to opening of the left renal artery with off-the-shelf solution. The patient had an uneventful recovery with a resolution of the rAAA. She is well and symptom-free 6 months later.

Conclusion

Endovascular aneurysm repair (EVAR) in emergent elderly rAAA with hostile neck and severe tortuous iliac artery is extremely challenging, and endovascular management with integrated technique is feasible and may achieve a satisfactory early result.

The impact of endovascular repair of ruptured abdominal aortic aneurysm on the gastrointestinal and renal function

Introduction. Systemic effects of ruptured abdominal aortic aneurysm (rAAA) may be altered by the mode of surgery. This study aimed to determine systemic effects of endovascular aneurysm repair (EVAR) compared to open repair (OR). Patients and Methods. Consecutive patients with rAAA were repaired by OR or EVAR according to computerised tomographic (CT) findings. Renal function was monitored by estimated glomerular filtration rate (eGFR), serum urea and creatinine, and urinary albumin creatinine ratio (ACR). Hepatic function was assessed postoperatively for 5 days. Intestinal function was determined by the paracetamol absorption test. Intestinal permeability was assessed by urinary lactulose/mannitol ratio. Results. 30 rAAA patients were included. Fourteen had eEVAR and sixteen eOR. Serum urea were higher in eOR, while creatinine was similar between groups. Hepatic function showed no intergroup difference. Paracetamol absorption was increased in eEVAR group at day 3 compared to day 1 (P = 0.03), with no similar result in eOR (P = 0.24). Peak lactulose/mannitol ratio was higher in eOR (P = 0.03), with higher urinary L/M ratio in eOR at day 3 (P = 0.02). Clinical intestinal function returned quicker in eEVAR (P = 0.02). Conclusion. EVAR attenuated the organ dysfunction compared to open repair. However, a larger comparative trial would be required to validate this. The clinical trial is registered with reference number EUDRACT: 2013-003373-12.