Comparison of endovascular aneurysm repair with open repair in patients with abdominal aortic aneurysm (EVAR trial 1), 30-day operative mortality results: randomised controlled trial

Machine learning for endoleak detection after endovascular aortic repair

Diagnosis of endoleak following endovascular aortic repair (EVAR) relies on manual review of multi-slice CT angiography (CTA) by physicians which is a tedious and time-consuming process that is susceptible to error. We evaluate the use of a deep neural network for the detection of endoleak on CTA for post-EVAR patients using a novel data efficient training approach. 50 CTAs and 20 CTAs with and without endoleak respectively were identified based on gold standard interpretation by a cardiovascular subspecialty radiologist. The Endoleak Augmentor, a custom designed augmentation method, provided robust training for the machine learning (ML) model. Predicted segmentation maps underwent post-processing to determine the presence of endoleak. The model was tested against 3 blinded general radiologists and 1 blinded subspecialist using a held-out subset (10 positive endoleak CTAs, 10 control CTAs). Model accuracy, precision and recall for endoleak diagnosis were 95%, 90% and 100% relative to reference subspecialist interpretation (AUC = 0.99). Accuracy, precision and recall was 70/70/70% for generalist1, 50/50/90% for generalist2, and 90/83/100% for generalist3. The blinded subspecialist had concordant interpretations for all test cases compared with the reference. In conclusion, our ML-based approach has similar performance for endoleak diagnosis relative to subspecialists and superior performance compared with generalists.

Daphnetin suppresses experimental abdominal aortic aneurysms in mice via inhibition of aortic mural inflammation

Rupture of abdominal aortic aneurysm (AAA) is a devastating event that can be prevented by inhibiting the growth of small aneurysms. Therapeutic strategies targeting certain events that promote the development of AAA must be developed, in order to alter the course of AAA. Chronic inflammation of the aortic mural is a major characteristic of AAA and is related to AAA formation, development and rupture. Daphnetin (DAP) is a coumarin derivative with anti-inflammatory properties that is extracted from Daphne odora var. However, the effect of DAP on AAA development remains unclear. The present study investigated the effect of DAP on the formation and development of experimental AAAs and its potential underlying mechanisms. A mice AAA model was established by intra-aortic infusion of porcine pancreatic elastase (PPE), and mice were intraperitoneally injected with DAP immediately after PPE infusion. The maximum diameter of the abdominal aorta was measured by ultrasound system, and aortic mural changes were investigated by Elastica van Gieson (EVG) staining and immunohistochemical staining. The results demonstrated that DAP significantly suppressed PPE-induced AAA formation and attenuated the depletion of aortic medial elastin and smooth muscle cells in the media of the aorta. Furthermore, the density of mural macrophages, T cells and B cells were significantly attenuated in DAP-treated AAA mice. In addition, treatment with DAP resulted in a significant reduction in mural neovessels. These findings indicated that DAP may limit the formation and progression of experimental aneurysms by inhibiting mural inflammation and angiogenesis. These data confirmed the translational potential of DAP inclinical AAA inhibition strategies.

EVAR: Open Surgical Repair Options for Persistent Type Ia Endoleaks

Abdominal aortic aneurysm (AAA) is a disease of the elderly which may result in aneurysm rupture if not treated in a timely manner. The incidence of AAA has increased in part due to patient and physician education, ultrasound screening, and liberal use of computed tomography imaging in conjunction with an aging population. Endovascular aneurysm repair has become the preferred treatment for surgeons and interventionalists. When endografts are placed outside of device-specific instructions for use, the risk of endoleak development is significantly increased. Open surgical repair of Type Ia endoleaks is recommended when endovascular options have been exhausted. Open surgical repair of Type Ia endoleaks provides acceptable perioperative morbidity and mortality rates, long-term durability, and low reintervention rates when performed in the elective setting.

Five Year Patient Outcomes of Endovascular Abdominal Aortic Aneurysm Repair in the ENDURANT France Registry

OBJECTIVE

Endovascular repair is the preferred method of treatment for infrarenal abdominal aortic aneurysms with numerous publications from multiple geographic regions showing excellent patient outcomes. Since the original ACE (Anevrysme de l'aorte abdominale: Chirurgie versus Endoprothese) randomised control trial, studies of French specific population have also contributed significantly to the body of evidence in support of endovascular abdominal aortic repair.

METHODS

In the ENDURANT France registry, 180 patients were consecutively enrolled from 20 French centres starting in 2012. Investigational sites included public and private practice and differing centre volumes to be as representative of real world French experience as possible. The aim of this study was to present the five year outcomes from this registry.

RESULTS

Instructions for use (IFU) were respected in 97.8% (176/180) of patients. At five years, the Kaplan-Meier overall survival was 69.9% ± 3.5% and the freedom from aneurysm related death was 97.6% ± 1.2%. The freedom from Type IA endoleaks was 94.5% ± 1.7%, freedom from endoleaks of any type was 70.1 ± 3.4%, and freedom from secondary endovascular procedure 90.4% ± 2.6%. In addition, 61.6% (45/73) of patients exhibited sac shrinkage at five years.

CONCLUSION

In this five year report of the Endurant France registry, survival, re-intervention, and freedom from endoleak rates were comparable to recent EVAR registries and there was a high sac shrinkage rate. Secondary procedure and aneurysm rupture were lower than those of ACE, the French RCT which included older generation devices. This prospective registry demonstrates favourable five year outcomes of the Endurant stent graft used within IFU.

Current status on aortic endografts

Endovascular treatment has become widespread to treat aneurysmal disease, especially located in the aorta. The modern era of abdominal aortic aneurysm repair started between 1986 and 1991, and in the last 30 years, Endovascular Treatment for abdominal aortic aneurysms evolved both due to the development of new materials and devices and the increasing appeal and effectiveness of the endovascular therapy itself. Vascular surgeons are using nowadays different solutions of Endovascular Treatment to treat all the expressions of aortic pathology (aneurysms, dissections and trauma) both in the acute and elective setting. Despite its use in every location of the aorta (the ascending aorta, the aortic arch, the thoracic aorta, thoraco-abdominal aorta, pararenal, iuxtarenal and infrarenal aortic aneurysms and iliac aneurysms), its safety and efficiency, endovascular treatment for aortic aneurysms presents some drawbacks: despite a lower short-term morbi-mortality, reinterventions and long-term patency are higher compared to open repair. In this review, we detail the most used types of endografts according to location, their performances and durability for each device. We conclude by discussing options to overcome ET limitations. Therefore, an obvious question arises: what we need in the future? What can the technological progress gives to physicians to further improve this new way of treating aorta?

Involvement of Myeloid Cells and Noncoding RNA in Abdominal Aortic Aneurysm Disease

Significance: Abdominal aortic aneurysm (AAA) is a potentially fatal condition, featuring the possibility of high-mortality rupture. To date, prophylactic surgery by means of open surgical repair or endovascular aortic repair at specific thresholds is considered standard therapy. Both surgical options hold different risk profiles of short- and long-term morbidity and mortality. Targeting early stages of AAA development to decelerate disease progression is desirable. Recent Advances: Understanding the pathomechanisms that initiate formation, maintain growth, and promote rupture of AAA is crucial to developing new medical therapeutic options. Inflammatory cells, in particular macrophages, have been investigated for their contribution to AAA disease for decades, whereas evidence on lymphocytes, mast cells, and neutrophils is sparse. Recently, there has been increasing interest in noncoding RNAs (ncRNAs) and their involvement in disease development, including AAA. Critical Issues: The current evidence on myeloid cells and ncRNAs in AAA largely originates from small animal models, making clinical extrapolation difficult. Although it is feasible to collect surgical human AAA samples, these tissues reflect end-stage disease, preventing examination of critical mechanisms behind early AAA formation. Future Directions: Gaining more insight into how myeloid cells and ncRNAs contribute to AAA disease, particularly in early stages, might suggest nonsurgical AAA treatment options. The utilization of large animal models might be helpful in this context to help bridge translational results to humans.

Common Iliac Artery Aneurysm Repair with Hypogastric Preservation via Balloon-Expandable Covered Stents Using the Eyelet Technique-Iliac Branched Devices Still Inappropriate in Many Patients

BACKGROUND

Common iliac artery aneurysms (CIAAs) are seen in 20-40% of patients with abdominal aortic aneurysms. Historically treated with sacrifice of the hypogastric artery, which can result in significant morbidity related to pelvic ischemia, new devices have made hypogastric artery preservation more feasible but are only applicable to a small subset of aneurysm anatomy. We sought to assess the safety and efficacy or a novel technique for hypogastric artery preservation applicable to a wider variety of patients with CIAAs.

METHODS

We conducted a retrospective review of a prospectively maintained database of all patients with CIAAs treated with a novel endovascular technique at the UC San Diego Sulpizio Cardiovascular Center or the San Diego Veterans Affairs Hospital between March 2016 and December 2017. The endovascular technique involved stent placement in both the internal and external iliac arteries, with balloon expansion to minimize gutters between the endografts. Primary end points included technical success, limb patency, and presence of endoleaks (ELs).

RESULTS

A total of 14 limbs (12 patients) were treated for CIAAs with 100% technical success and limb patency at an average of 6.8 months of follow-up. No patients experienced type I or type III ELs or evidence of pelvic ischemia. Two patients required reintervention, and one patient died of causes unrelated to the procedure.

CONCLUSIONS

This technique was performed with excellent short- and mid-term safety in patients with varying aneurysm anatomy. The high rates of technical success and low rate pelvic ischemia represent improvement over conventional techniques that sacrifice the hypogastric artery and warrant further testing in a larger patient series with longer term follow-up.

Migration After Endovasclar Aneurysm Sealing in Conjunction With Chimney Grafts

Purpose

To assess the incidence of migration after endovascular aneurysm sealing (EVAS) in conjunction with chimney grafts (chEVAS) for repair of abdominal aortic aneurysms (AAAs).

Materials and Methods

A retrospective, observational cohort study was conducted of 31 patients (mean age 75.7 years; 27 men) treated for juxtarenal AAA between April 2013 and December 2018 at single centers in New Zealand and the Netherlands. The majority of patients received >1 chimney graft (13 single, 13 double, and 5 triple) during chEVAS. Six patients had only the first postoperative scan, so the migration analysis was based on 25 patients.

Results

Median seal length assessed on the first postoperative computed tomography scan was 36.5 mm. The assisted technical success rate was 93.5% with 2 technical failures. Median time to final imaging follow-up was 17 months in 25 patients. At the latest follow-up, there were no cases of caudal migration >10 mm. Freedom from caudal movement of 5 to 9 mm was estimated as 86.1% at 1 year and 73.9% at 2 years; freedom from clinically relevant migration (movement requiring reintervention) was 100% at both time intervals. However, at 3 years there were 2 cases of caudal movement of 5 to 9 mm and a type Ia endoleak warranting reintervention. No correlation between migration and aneurysm growth (p=0.851), endoleak (p=0.562), or the number of chimney grafts (p=0.728) was found. During follow-up, 2 patients (7%) had aneurysm rupture and 10 (33%) had reinterventions. Eight patients (27%) died; 2 were aneurysm-related (7%) and due to the consequences of a reintervention.

Conclusion

In the 2 years following chEVAS, there was no caudal migration >10 mm, but nearly a quarter of patients had caudal movement of 5 to 9 mm. A trend was observed toward ongoing migration that required intervention at 3-year follow-up. chEVAS is technically challenging and should be considered only for patients with no viable alternative treatment option.

Deep Learning and Multivariable Models Select EVAR Patients for Short-Stay Discharge

OBJECTIVES

We sought to develop a prediction score with data from the Vascular Quality Initiative (VQI) EVAR in efforts to assist endovascular specialists in deciding whether or not a patient is appropriate for short-stay discharge.

BACKGROUND

Small series describe short-stay discharge following elective EVAR. Our study aims to quantify characteristics associated with this decision.

METHODS

The VQI EVAR and NSQIP datasets were queried. Patients who underwent elective EVAR recorded in VQI, between 1/2010-5/2017 were split 2:1 into test and analytic cohorts via random number assignment. Cross-reference with the Medicare claims database confirmed all-cause mortality data. Bootstrap sampling was employed in model. Deep learning algorithms independently evaluated each dataset as a sensitivity test.

RESULTS

Univariate outcomes, including 30-day survival, were statistically worse in the DD group when compared to the SD group (all P < 0.05). A prediction score, SD-EVAR, derived from the VQI EVAR dataset including pre- and intra-op variables that discriminate between SD and DD was externally validated in NSQIP (Pearson correlation coefficient = 0.79, P < 0.001); deep learning analysis concurred. This score suggests 66% of EVAR patients may be appropriate for short-stay discharge. A free smart phone app calculating short-stay discharge potential is available through QxMD Calculate https://qxcalc.app.link/vqidis.

CONCLUSIONS

Selecting patients for short-stay discharge after EVAR is possible without increasing harm. The majority of infrarenal AAA patients treated with EVAR in the United States fit a risk profile consistent with short-stay discharge, representing a significant cost-savings potential to the healthcare system.

Myocardial injury after non-cardiac surgery (MINS) in EVAR patients: a retrospective single-centered study

BACKGROUND

Myocardial injury after non-cardiac surgery (MINS) stands for myocardial injury due to ischemia that occurs during or within 30-days after non-cardiac surgery. Although MINS is known to be independently associated with 30-day mortality after intervention, little is described about the impact of MINS after vascular procedures, particularly after endovascular aneurysm repair (EVAR).

METHODS

This is an observational, retrospective, single-centered study. All patients underwent elective standard EVAR between January 2008 and June 2017, and them with at least one postoperative measurement of troponin I in the first 48 h after surgery, were retrospectively included. MINS was defined as the value exceeding the 99^th percentile of a normal reference population with a coefficient of variation <10%. Primary outcomes include the prevalence of MINS in this subset of EVAR patients, as well as its impact in mid-term all-cause mortality. As secondary aim, the preoperative predictors of MINS were also assessed.

RESULTS

One-hundred and thirty-six patients with postoperative troponin measurements were included (95.6% male; mean age 75.51years). MINS was diagnosed in 16.2% (N.=22) of the patients, and in 86.4% of the cases (N.=19) it was completely asymptomatic. Heart failure (31.8% vs. 10.5%, P=0.016), ASA Score ≥3 (95.5% vs. 67.5%, P=0.004), pre-operative (P=0.036) and postoperative (P=0.04) hemoglobin concentrations ≤12 g/dL were found to be significantly associated with MINS. Regarding remaining baseline characteristics, anesthesia and femoral access, no further differences were observed. Survival at 1, 3 and 5 years was 92% (95% CI: 4.6-6.9, standard error [SE] 0.023), 81% (95% CI: 5.6-7.6, SE=0.034) and 71% (95% CI: 6.9-8.7, SE=0.04), with two deaths reported at 30 days follow-up. MINS was found to be significantly associated with increased mid-term all-cause mortality after EVAR at 24 months follow-up (84.2±3.4% vs. 63.6±10.3%, P=0.001), with a 2.12-fold risk increase of death.

CONCLUSIONS

MINS is a common complication after EVAR and negatively impacts the mid-term prognosis of such interventions. In the majority of cases, it is asymptomatic and, therefore, not detectable unless routine postoperative troponin measurements are performed.

Evolving Utility of Endovascular Treatment of Juxtarenal, Pararenal, and Suprarenal Abdominal Aortic Aneurysms Associated With Increased Risk of Mortality Over Time

BACKGROUND

Continued advances in endovascular technologies are resulting in fewer open abdominal aortic aneurysm (AAA) repairs. In addition, more complex juxtarenal, pararenal, and suprarenal (JPS) AAAs are being managed with various endovascular techniques. This study sought to evaluate the evolving trends in endovascular aneurysm repair (EVAR) of AAAs, hypothesizing increased rate of JPS AAA repair by EVAR. We also sought to evaluate the risk for morbidity and mortality for EVAR and open aneurysm repair (OAR) of JPS AAAs over time.

METHODS

The 2011-2017 American College of Surgeons National Surgical Quality Improvement Program Procedure-Targeted Vascular database was queried for patients undergoing OAR or EVAR for AAAs. A multivariable logistic regression analysis was performed for both infrarenal and JPS AAA repairs.

RESULTS

Of 18,661 patients who underwent AAA repair, 3,941 (21.1%) were OAR and 14,720 (78.9%) were EVAR. The rate of OAR decreased from 29.5% in 2011 to 21.3% in 2017 (P < 0.001) with a geometric-mean-annual decrease of 27.8%. The rate of EVAR increased from 70.5% to 78.7% during the same time period (P < 0.001) with a geometric-mean-annual increase of 11.6%. These trends remained true for both infrarenal and JPS AAAs. After adjusting for covariates, there was no difference in associated risk of 30-day mortality, renal complications, or ischemic colitis for either OAR or EVAR over each incremental year for infrarenal AAAs (P > 0.05). However, in patients undergoing EVAR for JPS AAAs, the associated risk of mortality increased with each incremental year (odds ratio [OR]: 1.30, confidence interval [CI]: 1.01-1.69, P = 0.039), whereas there was no difference in the risk of mortality for OAR of JPS AAAs with each incremental year (OR: 1.11, CI: 0.99-1.23, P = 0.067).

CONCLUSIONS

The rate of OAR for AAA has decreased over the past seven years with an increase in EVAR, particularly for more complex JPS AAAs. The associated risk for morbidity and mortality for treatment of infrarenal AAAs was not significantly affected by this increased utility of EVAR. The associated risk of mortality for JPS AAAs treated by EVAR increased over time, whereas this trend for associated risk of mortality was not seen for OAR of JPS AAAs. These findings, especially the increased associated risk of mortality over time with EVAR for JPS AAAs, warrant careful prospective analysis.

Predictors of Aneurysm Sac Shrinkage Utilizing a Global Registry

BACKGROUND

Aneurysm sac remodeling is a complex multifactorial process with unknown factors influencing sac regression after endovascular aortic aneurysm repair (EVAR). We sought to identify factors associated with this process by analyzing data obtained from patients treated with the GORE EXCLUDER endovascular aneurysm repair (EVAR) endoprosthesis from December 2010 to October 2016 enrolled in the Global Registry for Endovascular Aortic Treatment (GREAT).

METHODS

All patients enrolled in GREAT with three years CT angiography (CTA) follow-up in each of the three successive years after EVAR were included. The percentage of sac size reduction toward device diameter was calculated and used as a surrogate for sac regression with the formula used being: sac size reduction = ((AAA baseline diameter - AAA diameter at follow-up)/(AAA baseline diameter - device diameter))∗100. The cohort was divided into two groups in accordance with the percentage of aneurysm sac reduction at three years; one with the top quartile of patients and the other with the lowest three quartiles. Demographic and procedural variables were analyzed using univariate and regression modeling to determine factors predictive of sac regression.

RESULTS

There were 3265 subjects enrolled with follow-up as of May 2018 of which 526 (16.2%) had three years of CTA surveillance. Overall aneurysm sac size decreased from a mean of 58.0 mm (Std Dev: 10.4, range: 34.2, 100.0) to a mean of 49.3 mm (Std Dev: 14.1, range: 0, 140) for a percentage reduction toward device diameter of a mean 28.2% (Std Dev: 39.0, range: -103.7, 183.9). On multivariate logistic regression model; two factors proved to be statistically significant contributors to a larger percentage reduction in aneurysm sac: a conical neck (odds ratio [OR] = 1.64, P-value = 0.023) and a larger proximal device diameter (OR = 1.09, P-value = 0.023). On the other hand, two factors were negative predictors of sac shrinkage, namely: old age (OR = 0.96, P-value = 0.002) and larger baseline aneurysm sac diameter (OR = 0.98, P-value = 0.028).

CONCLUSIONS

Aneurysms with conical necks and larger proximal device neck diameters have an increased percentage change in sac size over time after EVAR. Older age and larger initial diameters of aneurysms were negatively associated with percentage change in sac size as well as sac regression. Further study is needed to determine the clinical utility of these observations and applicability across multiple endoprosthesis platforms.

Patient radiation dose from x-ray guided endovascular aneurysm repair: a Monte Carlo approach using voxel phantoms and detailed exposure information

Endovascular aneurysm repair (EVAR) is a well-established minimally invasive technique that relies on x-ray guidance to introduce a stent through the femoral artery and manipulate it into place. The aim of this study was to estimate patient organ and effective doses from EVAR procedures using anatomically realistic computational phantoms and detailed exposure information from radiation dose structured reports (RDSR). Methods: Lookup tables of conversion factors relating kerma area product (P_KA) to organ doses for 49 different beam angles were produced using Monte Carlo simulations (MCNPX2.7) with International Commission on Radiological Protection (ICRP) adult male and female voxel phantoms for EVAR procedures of varying complexity (infra-renal, fenestrated/branched and thoracic EVAR). Beam angle specific correction factors were calculated to adjust doses according to x-ray energy. A MATLAB function was written to find the appropriate conversion factor in the lookup table for each exposure described in the RDSR, perform energy corrections and multiply by the respective exposure P_KA. Using this approach, organ doses were estimated for 183 EVAR procedures in which RDSRs were available. A number of simplified dose estimation methodologies were also investigated for situations in which RDSR data are not available. Results: Mean estimated bone marrow doses were 57 (range: 2-247), 86 (2-328) and 54 (8-250) mGy for infra-renal, fenestrated/branched and thoracic EVAR, respectively. Respective effective doses were 27 (1-208), 54 (1-180) and 37 (5-167) mSv. Dose estimates using non-individualised, average conversion factors, along with those produced using the alternative Monte Carlo code PCXMC, yielded reasonably similar results overall, though variation for individual procedures could exceed 100% for some organs. In conclusion, radiation doses from x-ray guided endovascular aneurysm repairs are potentially high, though this must be placed in the context of the life sparing nature and high success rate for this procedure.

Effect of obesity on radiation exposure, quality of life scores, and outcomes of fenestrated-branched endovascular aortic repair of pararenal and thoracoabdominal aortic aneurysms

BACKGROUND

The aim of the present study was to assess the effect of obesity on procedural metrics, radiation exposure, quality of life (QOL), and clinical outcomes of fenestrated-branched endovascular aortic repair (FB-EVAR) of pararenal and thoracoabdominal aortic aneurysms.

METHODS

We reviewed the clinical data from 334 patients (236 men; mean age, 75 ± 8 years) enrolled in a prospective nonrandomized study to evaluate FB-EVAR from 2013 to 2019. The patients were classified using the body mass index (BMI) as obese (BMI ≥30 kg/m²) or nonobese (BMI <30 kg/m²). QOL questionnaires (short-form 36-item questionnaire) and imaging studies were obtained preoperatively and at 2 months and 6 months postoperatively, and annually thereafter. The procedures were performed using two different fixed imaging systems. The end points included procedural metrics (ie, total operative time, fluoroscopic time, contrast volume), radiation exposure, technical success, 30-day mortality, and major adverse events, QOL changes, freedom from target vessel instability, freedom from reintervention, and patient survival.

RESULTS

The aneurysm extent was a pararenal aortic aneurysm in 117 patients (35%) and a thoracoabdominal aortic aneurysm in 217 patients (65%). Both groups had similar demographics, cardiovascular risk factors, and aneurysm extent, except for a greater incidence of hyperlipidemia and diabetes among the obese patients (P < .05). No significant differences were found in the procedural metrics or intraprocedural complications between the groups, except that the obese patients had greater radiation exposure than the nonobese patients (mean, 2.5 vs 1.6 Gy; P < .001), with the highest radiation exposure in those obese patients who had undergone the procedure using system 1 (fusion alone) instead of system 2 (fusion and digital zoom; mean, 4.1 vs 1.5 Gy; P < .001). Three patients had died within 30 days (0.8%), with no difference in mortality or major adverse events between the groups. The mental QOL scores had improved in the obese group at 2 and 12 months compared with the nonobese patients, with persistently higher scores up to 3 years. At 3 years, the obese and nonobese patients had a similar incidence of freedom from target vessel instability (74% ± 6% vs 80% ± 3%; P = .99, log-rank test), freedom from reintervention (66% ± 6% vs 73% ± 4%; P = .77, log-rank test), and patient survival (83% ± 5% vs 75% ± 4%; P = .16, log-rank test).

CONCLUSIONS

FB-EVAR was performed with high technical success and low mortality and morbidity, with no significant differences between the obese and nonobese patients. The procedural metrics and outcomes were similar, with the exception of greater radiation exposure among obese patients, especially for the procedures performed using system 1 with fusion alone compared with system 2 (fusion and digital zoom). Obese patients had higher QOL mental scores at 2 and 12 months, with a similar reintervention rate, target vessel outcomes, and survival compared with nonobese patients.

Management of Abdominal Aortic Aneurysm Disease: Similarities and Differences Among Cardiovascular Guidelines and NICE Guidance

The development of endovascular techniques has improved abdominal aortic aneurysm (AAA) management over the past 2 decades. Different cardiovascular societies worldwide have recommended the endovascular approach as the standard of care in their currently available guidelines. While endovascular treatment has established its role in daily clinical practice, a new debate has arisen regarding the indications, appropriateness, limitations, and role of open surgery. To inform this debate, the MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched from 2010 to May 2020; the systematic search identified 5 articles published between 2011 and 2020 by 4 cardiovascular societies and the National Institute of Health and Care Excellence (NICE). Four debatable domains were assessed and analyzed: diagnostic methods and screening, preoperative management, indications and treatment modalities, and postoperative follow-up and endoleak management. The review addresses controversial proposals as well as widely accepted recommendations and "gray zone" issues that need to be further investigated and analyzed, such as screening in women, medical management, and follow-up imaging. While the recommendations for AAA management have significant overlap and agreement among international cardiovascular societies, the NICE guidelines diverge regarding the role of open repair in aortic disease, recommending conventional surgery in most elective cases.

Comparison of the Short and Long-Term Outcomes of Endovascular Repair and Open Surgical Repair in the Treatment of Unruptured Abdominal Aortic Aneurysms: Meta-Analysis and Systematic Review

Background

Although the initial results of endovascular repair (EVAR) were promising, a comparison of its long-term efficacy against open surgical repair (OSR) remains largely elusive, and late-onset adverse events have not been systematically evaluated. Since OSR and EVAR are currently the only treatment options available in the management of abdominal aortic aneurysms (AAAs), the main question arising in clinical practice is whether EVAR or OSR confers more favourable short and long-term outcomes for patients presenting with unruptured AAAs.

Aims

The present meta-analysis aims to draw a head-to-head comparison between EVAR and OSR and facilitate the formulation of an evidence-based approach to the clinical management of unruptured AAAs.

Methods

A systematic review was conducted using three databases to identify all relevant studies with comparative data on EVAR vs. OSR. All-cause mortality was the primary outcome. Procedural outcomes, such as stroke, myocardial infarction, renal complications, rupture, and reintervention rates, were determined as secondary outcomes.

Results

Sixteen studies were included for comparative analysis, including four randomised-controlled trials and six non-randomised comparative clinical trials. EVAR conferred a clear perioperative survival advantage as compared to OSR (P < 0.00001). However, this survival advantage did not persist beyond two years post-procedure; all-cause mortality rates were comparable between the two treatment groups at two years (P = 0.09), four years (P = 0.58), and six years (P = 0.88) post-procedure. Although no statistically significant differences in aneurysm-related mortality, postoperative stroke, or myocardial infarction were identified, the OSR group had a statistically significant higher rate of postoperative renal complications. On the other hand, there was a statistically significant higher rate of rupture and reintervention following EVAR.

Conclusion

Whether the initial survival advantage afforded by EVAR is sufficient to justify the long-term risk of rupture, reintervention, and long-term mortality should be determined on a case-by-case basis by the multidisciplinary team overseeing the clinical care of the patient. Currently, it is reasonable to conclude that EVAR is as efficacious as OSR, but it would be invalid to claim it as superior. Ultimately, longer follow-up data must be presented before any definitive conclusions can be established for this potentially revolutionary technique. Presently, one can neither advocate nor refute EVAR over OSR.

Open vs. endovascular thoracoabdominal aortic aneurysm repair: tale of the tape

Open surgical repair persists as the gold-standard operation for thoracoabdominal aortic aneurysm; however, endovascular repair has become commonplace. Technical considerations in thoracoabdominal aortic aneurysm treatment are particularly complex, insofar as it involves critical branching arteries feeding the visceral organs. Newer, low-profile devices make total endovascular thoracoabdominal aortic aneurysm repair more feasible and, thus, appealing. For younger and low-risk patients, the choice between open and endovascular therapy remains controversial. Despite the advantages of a minimally invasive procedure, data suggest that endovascular aortic repair incurs a greater risk of spinal cord deficit, and the durability of endovascular aortic repair remains unclear. It is difficult to compare outcomes between endovascular and open thoracoabdominal aortic aneurysm repair, primarily because of the current investigational status of endovascular devices, the variety of approaches to endovascular repair, differing patient populations, lack of prospective randomized studies, and minimal medium- and long-tern follow-up data on endovascular repair. When deciding between open and endovascular approaches, one should consider which is more suitable for each patient. Older patients generally benefit from a less invasive approach. Open repair should be considered for young patients and those with heritable thoracic aortic disease. Infection and fistulae are best treated by open repair, although endovascular intervention as a lifesaving bridge to definitive repair has evolved to become a critical component of initial treatment. It is crucial to have technical expertise in both open and endovascular procedures to provide the best aortic repair for the patient. This may require dedicated aortic programs at tertiary institutions.

A penalized spline fitting method to optimize geometric parameters of arterial centerlines extracted from medical images

In order to grasp the spatial and temporal evolution of vascular geometry, three-dimensional (3D) arterial bending structure and geometrical changes of arteries and stent grafts (SG) must be quantified using geometrical parameters such as curvature and torsion along the vasculature centerlines extracted from medical images. Here, we develop a robust method for constructing smooth centerlines based on a spline fitting method (SFM) such that the optimized geometric parameters of curvature and torsion can be obtained independently of digitization noise in the images. Conventional SFM consists of the 3rd degree spline basis function and 2nd derivative penalty term. In contrast, the present SFM uses the 5th degree spline basis function and 3rd and 4th derivative penalty terms, the coefficients of which are derived by the Akaike information criterion. The results show that the developed SFM can reduce the errors of curvature and torsion compared to conventional SFM. We then apply the present SFM to the centerline of the SG in an abdominal aortic aneurysm (AAA), and those of bilateral internal carotid arteries (ICA) in 6 cases: 3 cases with aneurysms and 3 cases without any aneurysm. The SG centerlines were obtained from temporal medical images at three scan times. The strong peak of the curvature could be clearly observed in the distal area of the SG, the inversion of the torsion at 0 months in the middle area of SG disappeared over time, and the torsions around the SG bifurcation at the three time periods were inverted. The curvature-torsion graphs along the ICA centerlines superimposing five aneurysmal positions were useful for investigating the relationship between arterial bending structure and aneurysmal positions. Both ICAs had curvature peak values higher than 0.4 within the ICA syphons. The ICA torsion graphs indicated that left and right ICA tended to be a right- and left-handed helix, respectively. In the left ICA syphon, the biggest aneurysm could be observed downstream of the salient torsion inversion. All aneurysms for 3 cases were positioned at the downstream of the inverted torsion.

Midterm survival after endovascular repair of intact abdominal aortic aneurysms is improving over time

OBJECTIVE

There is a growing body of literature raising concerns about the long-term durability of endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAAs), suggesting that long-term outcomes may be better after open AAA repair. However, the data investigating these long-term outcomes largely originate from early in the endovascular era and therefore do not account for increasing clinical experience and technologic improvements. We investigated whether 4-year outcomes after EVAR and open repair have improved over time.

METHODS

We identified all EVARs and open repairs for intact infrarenal AAA within the Vascular Quality Initiative database (2003-2018). We then stratified patients by procedure year into treatment cohorts of four years: 2003-2006, 2007-2010, 2011-2014, and 2015-2018. We used Kaplan-Meier analysis and Cox proportional hazards models to assess whether the survival after EVAR or open repair changed over time. In addition, we propensity matched EVAR and open repairs for each time cohort to investigate whether the relative survival benefit of EVAR over open repair changed over time.

RESULTS

We included 42,293 EVARs (increasing from 549 performed between 2003 and 2006 to 25,433 between 2015 and 2018) and 5189 open AAA repairs (increasing from 561 to 2306). Four-year survival increased for the periods 2003-2006, 2007-2010, 2011-2014, and 2015-2018 after both EVAR (76.6% vs 79.7% vs 83.5% vs 87.3%; P < .001) and open repair (82.2% vs 85.8% vs 87.7% vs 88.9%; P = .026). After risk adjustment, compared with 2003-2006, hazard of mortality up to 4 years after EVAR was lower for those performed between 2011 and 2014 (hazard ratio [HR], 0.72; 95% confidence interval [CI], 0.59-0.87; P = .001) and for those performed between 2015 and 2018 (HR, 0.56; 95% CI, 0.46-0.68; P < .001). In contrast, the risk-adjusted hazard of mortality was similar between open repair cohorts (2011-2014: HR, 0.81 [95% CI, 0.61-1.08; P = .15]; and 2015-2018: HR, 0.86 [95% CI, 0.64-1.17; P = .34]). Finally, in matched EVAR and open repairs, there was no difference in mortality in the first three cohorts, whereas the hazard of mortality was lower for the 2015-2018 cohort (HR, 0.65; 95% CI, 0.51-0.84; P = .001).

CONCLUSIONS

Four-year survival improved in more recent years after EVAR but not after open repair. This finding suggests that midterm outcomes after EVAR are improving, perhaps because of technologic improvements and increased experience, information that should be considered by surgeons and policymakers alike in evaluating the value of contemporary EVAR and open AAA repair.

A Case Report on Endovascular Aortic Repair Rupture

Endovascular repair of an abdominal aortic aneurysm (AAA) is a widely accepted alternative to open surgical AAA repair. A ruptured AAA is among the emergency surgeries with the highest risk of death, with an overall mortality rate close to90%. However, the classic symptom triad for ruptured AAAs of hypotension, a pulsatile mass, and abdominal/back pain is seen in only in 25% to 50% of affected patients. Thus, many present with symptoms and signs that suggest adifferent diagnosis. Recognizing uncommon presentations and limitations of imaging and interpretation, in addition to clinical gestalt, can save many lives. This report discusses an unusual case involving a previously repaired AAA presenting with acute rupture at the endograft site.

Impact of Gradual Adoption of EVAR in Elective Repair of Abdominal Aortic Aneurysm: A Retrospective Cohort Study from 2009 to 2015

INTRODUCTION

The recommendations about the preferred type of elective repair of abdominal aortic aneurysm (AAA) still divides guidelines committees, even nowadays. The aim is to assess outcomes after AAA repair focusing on differences between endovascular aneurysm repair (EVAR) and open surgical repair (OSR).

METHODS

The observational retrospective cohort study of consecutive patients submitted to elective AAA repair at a tertiary center, 2009-2015. Exclusion criteria were as follows: nonelective cases or complex aortic aneurysms. Primary outcomes were postoperative complications, length of hospital stay, survival, freedom from aortic-related mortality, and vascular reintervention. Time trends were assessed along the period under analysis.

RESULTS

From a total of 211 included patients, those submitted to EVAR were older (74 ± 7 vs. 67 ± 9 years; P < 0.001), presented a higher prevalence of hypertension (83.5% vs. 68.5%, P = 0.004), obesity (28.7% vs. 14.3%, P = 0.029), previous cardiac revascularization (30.5% vs. 14.7%, P = 0.005), heart failure (17.2% vs. 5.2%, P = 0.013), and chronic obstructive pulmonary disease (32.8% vs. 13.3%, P = 0.002). Patients were followed during a median of 49 months. EVAR resulted in a significantly shorter length of hospital stay (median 4 and interquartile range 3 vs. 8 (9); P < 0.001), lower 30-day complications (10.6% vs. 22.8%, P = 0.017), lower aortic-related mortality, and similar reintervention after adjustment with a propensity score. Along the time under analysis, EVAR became the predominate type of repair (P = 0.024), the proportion of complications decreased (P = 0.014), and the 30-day mortality (P = 0.035).

CONCLUSIONS

Although EVAR was offered to patients with more comorbidities, better and durable outcomes were achieved after EVAR, favoring its adoption for elective AAA repair.

Changes in Neck Angle, Neck Length, Maximum Diameter, Maximum Area and Thrombus after Endovascular Aneurysm Repair

Purpose

The correlation of initial anatomy of the aneurysm, aneurysmal remodeling and endoleaks is controversial. We performed a retrospective study to measure aneurysmal remodeling with time, and to assess the structural changes in the aneurysm neck after endovascular aneurysm repair (EVAR).

Materials and Methods

From January 2013 to February 2018, 108 patients with abdominal aortic aneurysms (AAA) underwent EVAR. Follow-up computed tomography images were available for 90 patients. Anatomic variables, including the neck angle, neck length, maximal diameter, maximal area, and thrombus volume were measured. Temporal changes were measured preoperatively, immediate postoperatively (within 1 week after EVAR), and at 6 months, 1 year, and 2 years post-EVAR. Correlation between the variables according to the temporal changes and presence of type Ia endoleaks (T1aE) was analyzed.

Results

The mean follow-up period was 10.63±20.34 months. Significant decreases in neck angle and length occurred immediately postoperative (P<0.001 and 0.036). Maximum diameter decreased at 6 months post-EVAR (P=0.003), but no significant changes in the maximal area occurred over time (P=0.142). Thrombus volume in the aneurysm sac increased immediately post-EVAR (P=0.008). There was no significant relationship between T1aE and neck changes in the group and time comparison (P=0.815 and 0.970).

Conclusion

Changes in neck angle, length and thrombus volume occurred immediately after EVAR, whereas a change in the maximum diameter of the AAA was noted 6 months after EVAR. Preoperative anatomic variables related with T1aE were not found.

Reporting standards for endovascular aortic repair of aneurysms involving the renal-mesenteric arteries

Endovascular aortic aneurysm repair of complex aortic aneurysms requires incorporation of side branches using specially designed aortic stent grafts with fenestrations, directional branches, or parallel stent grafts. These techniques have been increasingly used and reported in the literature. The purpose of this document is to clarify and to update terminology, classification systems, measurement techniques, and end point definitions that are recommended for reports dealing with endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms involving the renal and mesenteric arteries.

Analysis of Radiation Exposure during Endovascular Aneurysm Repair

Endovascular aneurysm repair (EVAR) is now the preferred procedure for abdominal aortic aneurysm repair. As a result of the need for fluoroscopy during EVAR, radiation exposure is a potential hazard. We studied the quantity of radiation delivered during EVAR to identify risks for excessive exposure. Fluoroscopy time, contrast volume used, and procedural details were recorded prospectively during EVARs. Using data collected from similar EVARs, an equation was derived to calculate approximate dose-area product (DAP) from fluoroscopy time. DAP values were then compared between procedures in which a relevant postdeployment procedure (PDP) was necessary intraoperatively with those without. Clinical data on 17 patients were collected. The mean age of patients was 68 (±9) years. Fluoroscopy times and approximate DAP values were found to be significantly higher in the seven patients with a PDP compared with the 10 patients without an intraoperative PDP (31.2 [±9.6] vs 22.7 [±6.0] minutes, P = 0.033 and 537 [±165] vs 390 [±103] Gy-cm2, P = 0.033, respectively). The average amount of contrast volume used was not significantly different between groups. Radiation emitted during EVARs with PDPs was significantly greater relative to those without PDPs. Device design and operators should thus aim to decrease PDPs and to minimize fluoroscopy time.

Type IA endoleak caused by interlocked suprarenal bare-metal stents after endovascular abdominal aortic aneurysm repair with successful endovascular rescue

A physically active 90-year-old man underwent endovascular repair of an asymptomatic but enlarging abdominal aortic aneurysm. Postoperative computed tomography demonstrated entanglement of nonadjacent proximal bare-metal stents. This was associated with graft infolding and a type IA endoleak. The patient underwent percutaneous transluminal angioplasty and placement of a Palmaz stent. Subsequent surveillance imaging showed resolution of the type I endoleak >1 year later. This report demonstrates an uncommon cause of stent graft infolding, an already rare complication of endovascular aneurysm repair, and highlights the need to carefully assess the morphologic appearance of the proximal fixation stents after graft deployment.

Dilatation of Aortic Neck and Common Iliac Arteries after Open Repair of Abdominal Aortic Aneurysms: Long-Term Follow-Up According to Aortic Reconstruction Configuration

BACKGROUND

Several studies in the literature report continued proximal aorta and distal iliac artery dilatation after surgical correction of an abdominal aortic aneurysm (AAA). The purpose of this study is to evaluate these findings, in a South American population, and relate them to the type of configuration of the open procedure aortic reconstruction.

METHODS

This is a retrospective review of ultrasonographic follow-up of patients submitted to open repair of AAA from 1989 to 2013, reporting proximal aorta dilatation (≥3 cm) and distal iliac artery dilatation (≥1.5 cm).

RESULTS

A total of 155 patients were included. Life-table freedom at the intervals 11 < 15 years and ≥15 years were 47% and 23% for proximal dilatation and 63% and 38% for distal iliac arteries dilatation, respectively. There were more proximal and distal dilatations in patients submitted to more extensive aortic reconstructions (aorto-aortic 13% and 22% vs aorto-bilateral common iliacs 27% and 8% vs aorto-unilateral or bilateral external iliacs 27% and 32% and aorto-femoral 67% and 0%) P < 0.0001. Juxtarenal anastomosis was also correlated with more proximal dilatations (42% vs 21%, P = 0,046). There were two proximal and three distal anastomosis pseudoaneurysms.

CONCLUSIONS

The presence of more extensive degenerative disease at the time of operation, requiring juxtarenal or more distal iliac reconstructions, may pose an increased risk of proximal aorta and iliac artery dilatation during follow-up. This study corroborates that significant changes are found after 7 to 10 years of the operation, reinforcing the need for long-term monitoring.

Computed Tomography-Aortography Versus Color-Duplex Ultrasound for Surveillance of Endovascular Abdominal Aortic Aneurysm Repair

Background

Color-duplex ultrasonography (DUS) could be an alternative to computed tomography-aortography (CTA) in the lifelong surveillance of patients after endovascular aneurysm repair (EVAR), but there is currently no level 1 evidence. The aim of this study was to assess the diagnostic accuracy of DUS as an alternative to CTA for the follow-up of post-EVAR patients.

Methods

Between December 16, 2010, and June 12, 2015, we conducted a prospective, blinded, diagnostic-accuracy study, in 15 French university hospitals where EVAR was commonly performed. Participants were followed up using both DUS and CTA in a mutually blinded setup until the end of the study or until any major aneurysm-related morphological abnormality requiring reintervention or an amendment to the follow-up policy was revealed by CTA. Database was locked on October 2, 2017. Our main outcome measures were sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratios of DUS against reference standard CTA. CIs are binomial 95% CI.

Results

This study recruited prospectively 659 post-EVAR patients of whom 539 (82%) were eligible for further analysis. Following the baseline inclusion visit, 940 additional follow-up visits were performed in the 539 patients. Major aneurysm-related morphological abnormalities were revealed by CTA in 103 patients (17.2/100 person-years [95% CI, 13.9–20.5]). DUS accurately identified 40 patients where a major aneurysm-related morphological abnormality was present (sensitivity, 39% [95% CI, 29–48]) and 403 of 436 patients with negative CTA (specificity, 92% [95% CI, 90–95]). The negative predictive value and positive predictive value of DUS were 92% (95% CI, 90–95) and 39% (95% CI, 27–50), respectively. The positive likelihood ratio was 4.87 (95% CI, 2.9–9.6). DUS sensitivity reached 73% (95% CI, 51–96) in patients requiring an effective reintervention.

Conclusions

DUS had an overall low sensitivity in the follow-up of patients after EVAR, but its performance improved meaningfully when the subset of patients requiring effective reinterventions was considered.

Registration

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01230203.

Midterm evaluation of perigraft arterial sac embolization in endovascular aneurysm repair

OBJECTIVE

Management of clinically significant endoleaks (ELs) remains costly, time-consuming, and morbid. Unresolved ELs can result in rupture and mortality after endovascular aneurysm repair (EVAR). Perigraft arterial sac embolization (PASE) has been used to treat ELs diagnosed at the time of EVAR or during surveillance.

METHODS

A retrospective review of prospectively maintained databases was conducted. The databases were compiled from two institutions between 2006 and 2016. PASE was performed for type I, type II, or type III EL with a thrombin, contrast medium, and Gelfoam (Pfizer, New York, NY) slurry prepared as previously described. PASE was administered either at the time of EVAR (primary) or during surveillance (secondary). Safety end points included nontarget embolization, defined as neurologic or enteric clinical sequelae from lumbar artery or visceral artery embolization, allergic reaction, peripheral embolization, or rupture. Efficacy end points included successful resolution of EL and cessation of aneurysm sac growth on computed tomography (CT) scans with contrast enhancement.

RESULTS

A total of 66 patients included in the study were treated with PASE. Primary PASE was performed in 38 patients (58%) and secondary in 28 (42%). Within the total cohort, the average clinical and CT scan follow-up was 1.7 years (0.1-11.6 years). Four patients required open repair for residual high-pressure ELs (one type IIIB and three type I; 6%). Of the 95% of patients who did not require open conversion, aneurysm growth did not occur during the follow-up period. In the overall cohort, PASE was successful in 88% of type I EL and 73% of patients with type II EL. There was no evidence of recanalization after thrombosis of culprit vessel for EL. No patients suffered nontarget embolization, spinal ischemia, allergic reaction, post-EVAR rupture, or colonic ischemia.

CONCLUSIONS

Primary and secondary PASE proved to be a safe, effective, and durable tool in sac management in conjunction with EVAR. Treating ELs during or after EVAR with PASE has minimized the incidence of EL on CT scan and halted aneurysm growth in our cohort. Further studies are needed to confirm the long-term durability of PASE in reducing secondary interventions after EVAR.

Financial viability of endovascular aortic repair in the modern era

BACKGROUND

In the current era of cost containment, the financial impact of high-cost procedures such as endovascular aneurysm repair (EVAR) remains an area of intensive interest. Previous reports suggested slim to negative operating margins with EVAR, prompting widespread initiatives to reduce cost and to improve reimbursement. In 2015, the Centers for Medicare and Medicaid Services (CMS) announced the reclassification of EVAR to more specific diagnosis-related group (DRG) coding and predicted an overall increase in hospital reimbursement. The potential impact of this change has not been described.

METHODS

Patients undergoing elective EVAR at a single institution between January 2014 and December 2018 were identified retrospectively, then stratified by date. Group 1 patients underwent EVAR before DRG change in 2015 and were classified with DRG 237/238, major cardiovascular procedure. Group 2 patients underwent EVAR after the change and were classified as DRG 268/269, aortic/heart assist procedures. The total direct cost included implant cost, operating room (OR) labor, room and board, and other supply costs. Net revenue reflected real payer mix values without extrapolation based on standard Medicare rates. Hospital profit was defined as the contribution to indirect (CTI), subtracting total direct cost from net revenue.

RESULTS

A total of 188 encounters were included, 67 (36%) in group 1 and 121 (64%) in group 2. Medicare patients composed 84% of group 1 and 81% of group 2. CTI (profit) increased by $4447 (+123%) from $3615 in group 1 to $8062 in group 2. Net revenue per encounter increased by $2054 (+7.1%). In group 1, the higher reimbursement DRG code 237 was applied in 5 of 67 (7.5%) patients, whereas DRG code 268 was assigned in 19 of 121 (15.1%) patients in group 2. Total direct cost per encounter decreased by $2012 (-7.9%). This decrease in cost was driven by a reduction in implant cost, from a mean $16,914 per encounter in group 1 to a mean $15,655 in group 2 (-$1259 or -7.4% per encounter) and by a decrease in OR labor cost, $2838 in group 1 to $2361 in group 2 (-$477 or -17.0% per encounter).

CONCLUSIONS

A significant improvement in hospital CTI was observed for elective EVAR during the course of the study. The increased DRG reimbursement after the Centers for Medicare and Medicaid Services coding changes in 2015 was a major driver of this salutary change. Notably, efforts to reduce implant and OR cost as well as to improve coding and documentation accuracy over time had an equally important impact on financial return.

Cost-effectiveness of contrast-enhanced ultrasound for the detection of endovascular aneurysm repair-related endoleaks requiring treatment

OBJECTIVE

Follow-up after endovascular aneurysm repair is necessary to detect potentially life-threatening complications such as endoleaks. Computed tomography angiography (CTA) or magnetic resonance angiography (MRA) is often used as standard of care for follow-up. Contrast-enhanced ultrasound (CEUS) has been shown to be a viable and fast real-time nonionizing imaging modality with equivalent diagnostic accuracy while also being superior to color Doppler ultrasound. The aim of this cost-utility analysis was to evaluate the cost-effectiveness of this imaging method in comparison to others for the evaluation of endoleaks requiring treatment.

METHODS

A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with CTA, MRA, CEUS, and color Doppler ultrasound. Model input parameters were obtained from recent literature. The applied sensitivity and specificity values amounted to 90.5% and 100.0% for CTA, 96.0% and 100.0% for MRA, 94.0% and 95.0% for CEUS, and 82.0% and 93.0% for color Doppler ultrasound. Probabilistic and deterministic sensitivity analysis was performed to estimate uncertainty of model results. To evaluate cost-effectiveness, incremental cost-effectiveness ratios were reported as a measure representing the economic value of a strategy compared with an alternative. The willingness to pay was set to $100,000/QALY.

RESULTS

In the base-case scenario for a willingness to pay of $100,000 per QALY, CEUS was the most cost-effective of the four diagnostic strategies with estimated costs of $17,383 and effectiveness of 9.770 QALYs. CTA was estimated to result in lifetime costs of $17,679 with an expected effectiveness of 9.768 QALYs, whereas color Doppler ultrasound showed expected costs of $17,287 with 9.763 QALYs. Expected costs and effectiveness of MRA amounted to $17,945 and 9.771 QALYs each. Base-case estimates of the incremental cost-effectiveness ratios for CEUS vs color Doppler ultrasound equaled $14,173.52/QALY.

CONCLUSIONS

CEUS is a cost-effective imaging method for the evaluation of therapy-requiring endoleaks in endovascular aneurysm repair surveillance.

Short-term outcomes of the t-Branch off-the-shelf multibranched stent graft for reintervention after previous infrarenal aortic repair

OBJECTIVE

The purpose of this study was to evaluate the outcome of t-Branch (Cook Medical, Bloomington, Ind) stent graft for the treatment of thoracoabdominal and pararenal aortic aneurysms in patients who had previous infrarenal aortic repair.

METHODS

A retrospective two-center study was undertaken. All consecutive patients who underwent endovascular repair using t-Branch stent graft after previous infrarenal aortic repair between January 2010 and August 2018 were included. Demographics, past medical history, cardiovascular risk factors, and intraoperative and perioperative details were recorded. Technical success and early (30-day) mortality, morbidity, target vessel patency, and presence of endoleak were analyzed. During the first year of follow-up, survival, freedom from reintervention, and patency rates were recorded.

RESULTS

There were 32 patients (mean age, 74 ± 7 years; 81% male) included in the study; 24 (75%) patients had prior open surgical repair, and 8 (25%) patients had undergone standard endovascular aneurysm repair. The index operation was performed 9 ± 5 years earlier, including 10 ± 5 years for open surgical repair and 8 ± 6 years for endovascular aortic repair. The indication was progression of the disease in 26 patients (81%) and type IA endoleak in 6 patients (19%). The total number of target vessels incorporated was 117 arteries (3.8 ± 0.6 target vessels per patient). Eleven patients had only three vessels incorporated; celiac trunk was occluded in three patients, and eight patients had one functioning kidney. Technical success rate was 97% (31/32). There was a single technical failure in one patient who had a type IA endoleak after endovascular repair with suprarenal fixation. The stenotic right renal artery was not catheterized at the initial procedure, and retrograde access was achieved through a right subcostal incision 3 days later with successful completion of the repair. Early mortality rate was 13%, and spinal cord ischemia rate was 22% (7/32); four patients had permanent and three had transient neurologic deficits. Early target vessel patency was 100%, and the rate of any endoleak was 9% (3/32); two patients had type II endoleaks and one patient had type III endoleak. The mean follow-up was 5.4 ± 5.9 months. The cumulative survival rate was 82% and 73% at 6 and 12 months, respectively. The freedom from aorta-related mortality was 92% at 6 and 12 months. The cumulative freedom from reintervention during follow-up was 90% at 6 and 12 months. The overall target vessel patency rate was 100% and 97.5% at 6 and 12 months, respectively.

CONCLUSIONS

The use of t-Branch off-the-shelf stent graft for the treatment of aortic disease in patients who had previous infrarenal aortic repair appears to be feasible, with acceptable early outcomes in terms of morbidity and mortality.

Early and late outcomes of endovascular aneurysm repair to treat abdominal aortic aneurysm compared between severe and non-severe infrarenal neck angulation

Background

Abdominal aortic aneurysm with severe infrarenal neck angle (>60°) has long been thought to be an obstacle to endovascular aneurysm repair. However, some previous studies reported endovascular aneurysm repair to be safe and efficacious for treating abdominal aortic aneurysm in patients with severe neck angulation. The aim of this study was to investigate the early and late outcomes of endovascular aneurysm repair to treat abdominal aortic aneurysm compared between patients with severe and non-severe infrarenal neck angulation.

Methods

Fifty-four severe and 144 non-severe neck angulation patients who were treated at Siriraj Hospital (Bangkok, Thailand) during January 2010–October 2013 were recruited. The primary endpoints were intraoperative neck complications (e.g., type 1A endoleak or proximal graft migration) and immediate adjunct aortic neck procedures. The secondary endpoints included perioperative mortality, overall survival, and the proportion of patients that were reintervention-free at five years compared between the severe and non-severe groups.

Results

Severe angulation patients were significantly older than non-severe angulation patients (77 ± 6.3 vs. 74 ± 7.9 years; p =  0.021). The median proximal angle was significantly greater in the severe group (82° vs. 13.5°; p <  0.001). Intraoperative proximal neck complications developed in 29.6% of patients in the severe angulation group compared with 9.0% in the non-severe group ( p <  0.001). Significantly more patients in the severe group required intraoperative adjunct procedures (29.6% vs. 7.6%; p <  0.001). There was no significant difference in perioperative mortality between groups. At the five-year follow-up, there was no significant difference between groups for overall survival or the proportion of patients that remained reintervention-free.

Conclusions

Endovascular aneurysm repair to treat abdominal aortic aneurysm in patients with severe proximal neck angulation is technically feasible and safe Although the severe angulation group had a higher rate of intraoperative neck complications and immediate adjunct neck procedures than the non-severe group, there was no significant difference between groups for 30-day mortality, overall survival or the proportion of patients who remained reintervention-free at five years.

Outcomes after aortic aneurysm repair in patients with history of cancer: a nationwide dataset analysis

Background

Synchronous cancer in patients with abdominal aortic aneurysm (AAA) increases morbidity and mortality after AAA repair. However, little is known about the impact of the history of cancer on mortality after AAA repair.

Methods

Patients with intact AAA who were treated with endovascular aneurysm repair or open surgical repair were selected from the Health Insurance and Review Assessment data in South Korea between 2007 and 2016. Primary endpoints included the 30- and 90-day mortality and long-term mortality after AAA repair. The Cox proportional hazards models were constructed to evaluate independent predictors of mortality.

Results

A total of 1999 patients (17.0%, 1999/11785) were diagnosed with cancer prior to the AAA repair. History of cancer generally had no effect in short-term mortality at 30 and 90 days. However, short-term mortality rate of patients with a history of lung cancer was more than twice that of patients without it (3.07% vs. 1.06%, P = 0.0038, 6.14% vs. 2.69%, P = 0.0016). Furthermore, the mortality rate at the end of the study period was significantly higher in AAA patients with a history of cancer than in those without a history of cancer (21.21% vs. 17.08%, P < .0001, HR, 1.31, 95% CI, 1.17–1.46).

Conclusions

The history of cancer in AAA patients increases long-term mortality but does not affect short-term mortality after AAA repair. However, AAA repair could increase both short- and long-term mortality in patients with lung cancer history, and those cases should be more carefully selected.

National Numbers of Secondary Aortic Reinterventions after Primary Abdominal Aortic Aneurysm Surgery from the Dutch Surgical Aneurysm Audit

BACKGROUND

Long-term secondary aortic reinterventions (SARs) can be a sign of (lack of) effectiveness of abdominal aortic aneurysm (AAA) surgery. This study provides insight into the national number of SARs after primary AAA repair by endovascular aneurysm repair (EVAR) or by open surgical repair in the Netherlands.

METHODS

Observational study included all patients undergoing SAR between 2016 and 2017, registered in the compulsory Dutch Surgical Aneurysm Audit (DSAA). The DSAA started in 2013, SARs are registered from 2016. Characteristics of SAR and postoperative outcomes (mortality/complications) were analyzed, stratified by urgency of SAR. Data of SARs were merged with data of their preceded primary AAA repair, registered in the DSAA after January 2013. In these patients undergoing SAR, treatment characteristics of the preceded primary AAA repair were additionally described, with focus on differences between stent grafts.

RESULTS

Between 2016 and 2017, 691 patients underwent SAR, this concerned 9.3% of all AAA procedures (infrarenal/juxtarenal/suprarenal) in the Netherlands (77% elective/11% acute symptomatic/12% ruptured). Endoleak (60%) was the most frequent indication for SAR. SARs were performed with EVAR in 66%. Postoperative mortalities after SAR were 3.4%, 11%, and 29% in elective, acute symptomatic, and ruptured patients, respectively. In 26% (n = 181) of the patients undergoing SAR their primary AAA repair was performed after January 2013 and data of primary and SAR procedures could be merged. In 93% (n = 136), primary AAA repair was EVAR. Endografts primarily used were nitinol/polyester (62%), nitinol/polytetrafluoroethylene (8%), endovascular sealing (21%), and others (9%), compared with their national market share of 76% (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.38-0.71), 15% (OR, 0.50; CI, 0.29-0.89), 4.9% (OR, 5.04; CI, 3.44-7.38), and 4.1% (OR, 2.81; CI, 1.66-4.74), respectively.

CONCLUSIONS

In the Netherlands, about one-tenth of the annual AAA procedures concerns an SAR. A quarter of this cohort had an SAR within 1-5 years after their primary AAA repair. Most SARs followed after primary EVAR procedures, in which an overrepresentation of endovascular sealing grafts was seen. Postoperative mortality after SAR is comparable with primary AAA repair.

Postimplantation Syndrome Is Not Associated with Myocardial Injury after Noncardiac Surgery after Endovascular Aneurysm Repair

BACKGROUND

Postimplantation syndrome (PIS) is the clinical and biochemical expression of an inflammatory response following endovascular aneurysm repair (EVAR), with a reported incidence ranging from 2% to 100%. Although generally benign, some studies report an association between PIS and postoperative major adverse cardiovascular events (MACEs). Nonetheless, the role of PIS in postoperative myocardial injury after noncardiac surgery (MINS) is unknown. This work aims to evaluate the relationship between PIS and MINS in a subset of EVAR patients, as well as assess the impact of PIS in all-cause mortality.

METHODS

All patients undergoing elective standard EVAR between January 2008 and June 2017, and with at least one measurement of contemporary (cTnI) or high sensitivity troponin I (hSTnI) in the first 48h after surgery, were retrospectively analyzed. PIS was defined as the presence of fever and leukocytosis in the postoperative period in the absence of infectious complications. MINS was defined as the value exceeding the 99th percentile of a normal reference population with a coefficient of variation <10%, which was >0.032 ng/mL for cTnI and 0.0114 (female) and 0.027 ng/mL (male) for hSTnI. Patients' demographics, comorbidities, medication, access, and anesthesia were also evaluated.

RESULTS

One hundred thirty-three consecutive patients were included (95.5% male; mean age 75.66 ± 7.13 years). Mean follow-up was 46.35 months. Survival rate was 86.5%, 80.5%, and 57.6% at 1, 3, and 5 years of follow-up, with 2 fatalities at 30 days of follow-up. The prevalence of PIS was 11.4%. MACE occurred in 2.3% of the patients, while MINS was reported in 16.5% of the patients. No association was found between PIS and patients' gender, comorbidities, type of anesthesia, or transfusional support. The type of graft used significantly affected the prevalence of PIS, with all cases reported when polyester grafts were used (P = 0.031). MACE occurred in 2.3% of the patients, while MINS was reported in 16.5% of the patients. PIS was found to be significantly associated with postoperative MACE (P = 0.001), but not MINS. Survival analysis revealed no differences between patients with or without PIS regarding 30-day mortality as well as long-term all-cause mortality. American Society of Anesthesiologists score (hazard ratio [HR] 2.157, 95% confidence interval [CI] 1.07-4.33, P = 0.031) and heart failure (HR 2.284, 95% CI 1.25-4.18, P = 0.008) were found to be independently associated with increased long-term all-cause mortality in this cohort of patients.

CONCLUSIONS

PIS is a common complication after EVAR, occurring in 11.4% of the patients from this cohort. Graft type seems to significantly affect the risk of PIS, since all reported cases occurred when polyester grafts were used. PIS did not influence 30-day or long-term survival and was found to be significantly associated with postoperative MACE but not MINS, suggesting the involvement of different pathophysiological mechanisms.

Meta-analysis of phase-specific survival after elective endovascular versus surgical repair of abdominal aortic aneurysm from randomized controlled trials and propensity score-matched studies

OBJECTIVE

Although endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) significantly decreases perioperative mortality compared with open surgical repair (OSR), we have not concluded superiority between EVAR and OSR beyond the perioperative period. The aim of this study was to compare phase-specific survival after EVAR vs OSR.

METHODS

The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Embase and MEDLINE were searched up to November 2019 to identify randomized controlled trials and propensity score-matched studies that investigated ≥2-year all-cause mortality (primary outcome) after EVAR vs OSR for intact infrarenal AAA. For each study, the hazard ratio (HR) with 95% confidence interval (CI) of mortality for EVAR vs OSR was calculated using survival curves for the following specific phases: early term (0-2 years after repair), midterm (2-6 years after repair), long term (6-10 years after repair), and very long term (≥10 years after repair). The risk ratio (RR) in the perioperative (in-hospital or 30-day) period was also extracted. Phase-specific HRs or RRs were separately pooled using the random effects model. Sensitivity analyses were performed by removing one study at a time to confirm that our findings were not derived from any single study. Funnel plot asymmetry was also examined using the linear regression test.

RESULTS

Our search identified four randomized controlled trials and seven propensity score-matched studies enrolling a total of 106,243 AAA patients assigned to EVAR (n = 53,123) or OSR (n = 53,120). The mortality after EVAR compared with OSR was significantly lower in the perioperative period (RR, 0.39; 95% CI, 0.29-0.51; P < .00001) and similar in the early-term period (HR, 0.93; 95% CI, 0.84-1.03; P = .16). Notably, significantly higher mortality was observed in the EVAR group compared with the OSR group in the midterm period (HR, 1.15; 95% CI, 1.03-1.29; P = .01). However, similar mortality was observed between the EVAR group and the OSR group in the long-term (HR, 1.06; 95% CI, 0.96-1.17; P = .27) and very-long-term (HR, 1.17; 95% CI, 0.93-1.47; P = .19) periods. In sensitivity analyses, the significant benefit of EVAR in the perioperative period and that of OSR in the midterm period were not changed. No funnel plot asymmetry was identified in all analyses.

CONCLUSIONS

Compared with OSR, EVAR was associated with lower perioperative mortality and higher mortality in the midterm period for intact infrarenal AAA. The superiority of EVAR was absent in the early-term period, and the inferiority of EVAR in the midterm period disappeared in the long-term and very-long-term periods.