A Systematic Review of Predictors of Reintervention After EVAR: Guidance for Risk-Stratified Surveillance

Midterm Outcomes and Aneurysm Sac Dynamics Following Fenestrated Endovascular Aneurysm Repair after Previous Endovascular Aneurysm Repair

OBJECTIVE

Fenestrated endovascular aneurysm repair (FEVAR) is a feasible option for aortic repair after endovascular aneurysm repair (EVAR), due to improved peri-operative outcomes compared with open conversion. However, little is known regarding the durability of FEVAR as a treatment for failed EVAR. Since aneurysm sac evolution is an important marker for success after aneurysm repair, the aim of the study was to examine midterm outcomes and aneurysm sac dynamics of FEVAR after prior EVAR.

METHODS

Patients undergoing FEVAR for complex abdominal aortic aneurysms from 2008 to 2021 at two hospitals in The Netherlands were included. Patients were categorised into primary FEVAR and FEVAR after EVAR. Outcomes included five year mortality rate, one year aneurysm sac dynamics (regression, stable, expansion), sac dynamics over time, and five year aortic related procedures. Analyses were done using Kaplan-Meier methods, multivariable Cox regression analysis, chi square tests, and linear mixed effect models.

RESULTS

One hundred and ninety-six patients with FEVAR were identified, of whom 27% (n = 53) had had a prior EVAR. Patients with prior EVAR were significantly older (78 ± 6.7 years vs. 73 ± 5.9 years, p < .001). There were no significant differences in mortality rate. FEVAR after EVAR was associated with a higher risk of aortic related procedures within five years (hazard ratio [HR] 2.6; 95% confidence interval [CI] 1.1 - 6.5, p = .037). Sac dynamics were assessed in 154 patients with available imaging. Patients with a prior EVAR showed lower rates of sac regression and higher rates of sac expansion at one year compared with primary FEVAR (sac expansion 48%, n = 21/44, vs. 8%, n = 9/110, p < .001). Sac dynamics over time showed similar results, sac growth for FEVAR after EVAR, and sac shrinkage for primary FEVAR (p < .001).

CONCLUSION

There were high rates of sac expansion and a need for more secondary procedures in FEVAR after EVAR than primary FEVAR patients, although this did not affect midterm survival. Future studies will have to assess whether FEVAR after EVAR is a valid intervention, and the underlying process that drives aneurysm sac growth following successful FEVAR after EVAR.

Targeted proteomics and metabolomics for biomarker discovery in abdominal aortic aneurysm and post-EVAR sac volume

BACKGROUND AND AIMS

Abdominal aortic aneurysm (AAA) patients undergo uniform surveillance programs both leading up to, and following surgery. Circulating biomarkers could play a pivotal role in individualizing surveillance. We applied a multi-omics approach to identify relevant biomarkers and gain pathophysiological insights.

MATERIALS AND METHODS

In this cross-sectional study, 108 AAA patients and 200 post-endovascular aneurysm repair (post-EVAR) patients were separately investigated. We performed partial least squares regression and ingenuity pathway analysis on circulating concentrations of 96 proteins (92 Olink Cardiovascular-III panel, 4 ELISA-assays) and 199 metabolites (measured by LC-TQMS), and their associations with CT-based AAA/sac volume.

RESULTS

The median (25th-75th percentile) maximal diameter was 50.0 mm (46.0, 53.0) in the AAA group, and 55.4 mm (45.0, 64.2) in the post-EVAR group. Correcting for clinical characteristics in AAA patients, the aneurysm volume Z-score differed 0.068 (95 %CI: (0.042, 0.093)), 0.066 (0.047, 0.085) and -0.051 (-0.064, -0.038) per Z-score valine, leucine and uPA, respectively. After correcting for clinical characteristics and orthogonalization in the post-EVAR group, the sac volume Z-score differed 0.049 (0.034, 0.063) per Z-score TIMP-4, -0.050 (-0.064, -0.037) per Z-score LDL-receptor, -0.051 (-0.062, -0.040) per Z-score 1-OG/2-OG and -0.056 (-0.066, -0.045) per Z-score 1-LG/2-LG.

CONCLUSIONS

The branched-chain amino acids and uPA were related to AAA volume. For post-EVAR patients, LDL-receptor, monoacylglycerols and TIMP-4 are potential biomarkers for sac volume. Additionally, distinct markers for sac change were identified.

Reinterventions after TEVAR

Thoracic cardiovascular aortic repair is an alternative procedure to open surgery for degenerative thoracic aortic aneurysm and thoracic aortic dissection. The advancements in graft design and imaging techniques have expanded its utility. However, the long-term patency of thoracic endovascular aortic repair (TEVAR) graft is still a concern. This review delves into the literature on re-intervention following TEVAR, highlighting factors that influence the re-intervention rate.

Diagnosis of mental illness does not affect postoperative outcomes in patients undergoing endovascular aortic aneurysm repair in the VA healthcare system

OBJECTIVE

Mental illness can be a debilitating chronic disease associated with a higher likelihood of preexisting medical comorbidities and postoperative morbidity and mortality. Given the relative prevalence of mental health disorders among the veteran population, we sought to examine postoperative outcomes in patients undergoing endovascular aortic aneurysm repair (EVAR).

METHODS

Retrospective review of a single institution Veterans Administration Hospital operative database was used to identify patients who underwent EVAR from January 2010 to December 2021. Patients' demographics, comorbidities, medications, and intraoperative variables were collected. In addition, mental illness status was evaluated to stratify patients based on preexisting anxiety, depression, posttraumatic stress disorder, substance abuse disorder, or major psychiatric illness. The study's primary outcomes were postoperative complications, mortality, and follow-up rates. Secondary outcomes included hospital length of stay, readmission rates, and intervention rates.

RESULTS

A total of 241 patients underwent infrarenal EVARs at our institution. One hundred forty patients (58.1%) were diagnosed with mental illness, whereas 101 (41.9%) had no prior diagnosis of mental illness. Of the 241 patients, 65.7% had a history of substance abuse disorder, 38.6% depression, 29.3% post-traumatic stress disorder, 19.3% anxiety, and 3.6% major psychiatric illness. There was no statistical difference in the number of medical comorbidities, race, smoking status, or medications compared with patients without mental illness. We found no statistical difference in access type, wound infection rates, hypogastric coiling, estimated blood loss, and operating time. χ2 analysis demonstrated a statistically significant lower overall postoperative complication rate (28.6% vs 32.7%; P = .05) and decreased loss to follow-up (8.6% vs 15.8%; P = .05) among patients with a preexisting mental illness diagnosis. There were no statistically significant differences in readmission rate, length of stay, or 30-day mortality. When stratified by type of mental illness, binary logistic regression demonstrated no statistically significant differences in primary outcomes of postoperative complications, readmission rates, loss to follow-up, and 1-year mortality. Cox proportional hazards modeling demonstrated no significant difference in cumulative survival in patients diagnosed with a mental illness (0.56; 95% confidence interval, 0.29-0.107; P = .08).

CONCLUSIONS

There was no association between the presence of a prior mental health diagnosis and adverse outcomes following EVAR. Preceding mental illness did not correlate with an increased rate of complications, readmission, length of stay, or 30-day mortality in a veteran population. Lower loss to follow-up rates in patients with mental illness may reflect overall Veterans Health Administration expansion in resources and surveillance of these at-risk individuals. Further research is needed to assess the association between postoperative outcomes and mental illness.

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.

International RELAY®, branched outcomes - designed to respect and repair the thoracic aorta: A comparative analysis between double and triple branched configurations

BACKGROUND

Endovascular aortic arch repair (EAR) has emerged as an alternative to open surgical repair. A growing interest in endovascular repair techniques for aortic arch aneurysms and dissection has been met with a focus on the clinical efficacy of EAR devices. We present multicentre comparative data on the clinical outcomes associated with EAR using the double- and triple-branched configurations of the RELAY™ (Terumo Aortic, Scotland, UK) endograft.

METHODS

Multicentre data on EAR procedures, carried out from January 2019 to January 2022, using the double- and triple-branched RELAY™ endograft were collected prospectively. Follow-up data were collected at 30 days, 6 months, 12 months, and 24 months postoperative. Retrospective descriptive analysis, logistic regression, and Kaplan-Meier analysis were carried out on procedural and follow-up data.

RESULTS

A total of 131 patients were included in the series. In total, 103 and 28 patients were treated with the double-branched and triple-branched RELAY™ endograft, respectively. Over the 24-month follow-up period, zero mortality, cases of stroke, or reinterventions were recorded in the triple-branched group. Four mortalities, 19 disabling strokes, and 50 reinterventions were recorded in the double-branched group within 30 postoperative days. Target vessel patency was maintained in all patients in the triple-branched group, while vessel patency was maintained in 74.0% of patients in the double-branched group.

CONCLUSION

Outcomes associated with the triple-branched group are consistent with those reported in the literature. Our data suggest that EAR with the RELAY™ endograft is associated with favourable clinical outcomes and clinical efficacy. Further comparative research into EAR devices is needed.

Open conversion after failed endovascular aneurysm repair is increasing and its 30-day mortality is higher than that after primary open repair

BACKGROUND

Endovascular aneurysm repair (EVAR) has become the preferred treatment of abdominal aortic aneurysms (AAAs). Recent studies have demonstrated that cases of EVAR failure repair and subsequent open conversion have increased. The aim of the present study was to evaluate the national trend of annual cases and assess the 30-day outcomes of conversion to open repair after failed EVAR compared with primary open repair.

METHODS

The National Surgical Quality Improvement Program database was queried for relevant Current Procedural Terminology and International Classification of Diseases, Ninth and Tenth Revision, codes to identify patients who had undergone conversion to open repair or primary open repair of nonruptured AAAs from 2009 to 2018. The annual trend of cases was assessed, and the perioperative outcomes of both procedures were compared. Multivariable logistic regression analyses were conducted to identify independent perioperative factors associated with mortality.

RESULTS

Of the 9635 patients with nonruptured AAAs included in the present analysis, 9250 had undergone primary repair and 385 had required open conversion. During the 10-year period, the annual number of cases of open conversion had steadily increased and that of primary repair had decreased. The incidence of postoperative complications was similar between both groups, except for cardiac arrest, which had occurred more frequently in the open conversion group. The 30-day mortality was higher in the open conversion group than in the primary group (9.6% vs 3.9%; P < .0001). Open conversion was also independently associated with higher odds of death (adjusted odds ratio [OR], 2.1; 95% confidence interval [CI], 1.8-2.4; P < .0001). When the average mortality in both groups was compared between the first and last 5 years, no difference was found (open conversion: 9.8% vs 9.5% [P = 1.00]; primary repair: 3.6% vs 4.2% [P = .19]). Other perioperative factors independently associated with mortality included increased age (OR, 1.8; 95% CI, 1.5-2.1; P < .0001), American Society of Anesthesiologists class ≥III (OR, 2.7; 95% CI, 1.1-6.6; P = .029), insulin-dependent diabetes (OR, 2.0; 95% CI, 1.2-3.3; P = .005), chronic obstructive pulmonary disease (OR, 1.4; 95% CI, 1.1-1.8; P = .006), the presence of dyspnea at rest (OR, 3.3; 95% CI, 1.8-6.1; P < .0001), and a high preoperative hematocrit (OR, 0.94; 95% CI, 0.93-0.97; P < .0001).

CONCLUSIONS

Open conversion to treat nonruptured AAAs after failed EVAR was independently associated with higher mortality. Also, the annual cases of open conversion have continued to increase without any significant changes in postoperative mortality. This highlights the danger of open conversion and stresses the need for better solutions to prevent and manage EVAR failure.

Prognostic prediction models for endovascular abdominal aortic aneurysm repair: protocol for a scoping review

INTRODUCTION

Endovascular aneurysm repair (EVAR) has a marked short-term advantage over open surgical repair in managing abdominal aortic aneurysms (AAA); however, this benefit is lost in the long term. The current trend towards stratified medicine has given rise to diverse prognostic prediction models and scoring systems for EVAR. These models could act as decision support tools that employ patient and operative factors, to improve long-term outcomes. Past literature evaluated and compared model performance for predicting one outcome, for example, mortality. None were deemed competent for clinical application. The proposed study will use a scoping review approach to capture literature on prognostic modelling in EVAR for all predictable outcomes. The results are anticipated to inform future research, identify knowledge gaps, and assist in determining the potential of models for clinical use.

METHODS AND ANALYSIS

The proposed study will use the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping Reviews as a framework for conducting the review. PubMed Central, Embase and Cochrane Library will be searched and screened for peer-reviewed studies on prognostic modelling for EVAR, published between 2000 and 2022. No limits exist on predictor variables used and outcomes predicted by the model for inclusion, provided they apply to AAA patients managed with EVAR. Data will be abstracted using a charting form based on the Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies guidelines and PRISMA guidelines for systematic reviews. The Prediction model Risk of Bias Assessment Tool and the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis checklist will be used to critically appraise included studies.

ETHICS AND DISSEMINATION

Since scoping reviews cover secondary data from published literature, ethical approval is not required. The findings will be disseminated via peer-reviewed publications and presentations at key conferences.

Risk factors, risk stratification and risk-specific surveillance strategies after endovascular aneurysm repair: study protocol for a Delphi study by the International RIsk Stratification in EVAR (IRIS-EVAR) working group

INTRODUCTION

Several risk factors for adverse events after endovascular aneurysm repair (EVAR) have been described, but there is no consensus on their comparative prognostic significance, use in risk stratification and application in determining postoperative surveillance.

METHODS AND ANALYSIS

A scoping review of the literature was conducted to identify risk factors for adverse events after EVAR. Main adverse events were considered post-EVAR abdominal aortic aneurysm rupture and reintervention. Risk factors were grouped into four domains: (1) preoperative anatomy, (2) aortic device, (3) procedure performance and (4) postoperative surveillance. The Delphi methodology will be used to steer a group of experts in the field towards consensus organised into three tiers. In tier 1, participants will be asked to independently rate risk factors for adverse events after EVAR. In tier 2, the panel will be asked to independently rate a range of combinations of risk factors across the four domains derived from tier 1. A risk-stratification tool will then be built, which will include algorithms that map responses to signalling questions onto a proposed risk judgement for each domain. Domain-level judgements will in turn provide the basis for an overall risk judgement for the individual patient. In tier 3, risk factor-informed surveillance strategies will be developed. Each tier will typically include three rounds and rating will be conducted using a 4-point Likert scale, with an option for free-text responses.

ETHICS AND DISSEMINATION

Research Ethics Committee and Health Research Authority approval has been waived, since this is a professional staff study and no duty of care lies with the National Health Service to any of the participants. The results will be presented at regional, national and international meetings and will be submitted for publication in peer-reviewed journals. The risk stratification tool and surveillance algorithms will be made publicly available for clinical use and validation.

Rescue of Failed Aortic Repair with Fenestrated Endovascular Device

INTRODUCTION

The incidence of failed endovascular (EVAR) and open repair (OR) is increasing. Redo aortic repair is required in 10% of patients. Extension of the proximal sealing zone above the visceral arteries to adequate, healthier thoracic aorta using a fenestrated graft (FEVAR) can rescue a failing repair. A custom-made device can treat proximal type 1A endoleaks or proximal dilatation post endovascular or open repair, respectively. The aim of this investigation was to present a single-centre experience with FEVAR for patients with a failing aortic repair.

METHODS

A prospectively maintained database of FEVAR patients treated with a Zenithࣨ Fenestrated endovascular (ZFEN) device (Cook Medical LLC, Bloomington, Indiana, USA) was interrogated for individuals who had the device implanted as a rescue therapy after prior endovascular (EVAR) or open repair (OR). Statistical analysis was performed with SPSS v 25 software.

RESULTS

Between January 1, 2011 and March 31, 2019, 17 ZFEN devices were implanted. Ten patients had a type 1A endoleak from a prior EVAR and seven patients had proximal disease progression after prior OR. There were 12 males and 5 females, median age of 75 (interquartile range, IQR 7). 76.4% (n=13) of patients had an American Society of Anaesthesiologists (ASA) grade of 3. Primary technical success was 70.5% (n=12). Of the remainder, four cases (24%) had a type III endoleak at completion angiogram; of which, two patients (12%) required re-intervention within 30 days. One further case (6%) had primary assisted technical success as stenting of a flow limiting dissection flap in an iliac vessel was required. Peri-operative rate of deployment related complications and systemic complications were 5.8% (n=1) and 35% (n=6), respectively. Median length of hospital stay was 11 days (IQR 11). There was no mortality within the study follow up. Overall thirty-day re-intervention rate was 23.5%. Overall survival was 92% at one year.

CONCLUSION

FEVAR is a safe but technically challenging option for rescue of failing aortic repairs. These are a high risk group of patients and this is reflected in the high post-operative morbidity rate. Technical success was high and 30-day mortality was low.

Long-term Reintervention After Endovascular Abdominal Aortic Aneurysm Repair

OBJECTIVE

To describe the long-term reintervention rate after endovascular abdominal aortic aneurysm repair (EVR), and identify factors predicting reintervention.

SUMMARY OF BACKGROUND DATA

EVR is the most common method of aneurysm repair in America, and reintervention after EVR is common. Clinical factors predicting reintervention have not been described in large datasets with long-term follow-up.

METHODS

We studied patients who underwent EVR using the Vascular Quality Initiative registry linked to Medicare claims. Our primary outcome was reintervention, defined as any procedure related to the EVR after discharge from the index hospitalization. We used classification and regression tree modeling to inform a multivariable Cox-regression model predicting reintervention after EVR.

RESULTS

We studied 12,911 patients treated from 2003 to 2015. Mean age was 75.5 ± 7.3 years, 79.9% were male, and 89.1% of operations were elective. The 3-year reintervention rate was 15%, and the 10-year rate was 33%. Five factors predicted reintervention: operative time ≥3.0 hours, aneurysm diameter ≥6.0 cm, an iliac artery aneurysm ≥2.0 cm, emergency surgery, and a history of prior aortic surgery. Patients with no risk factors had a 3-year reintervention rate of 12%, and 10-year rate of 26% (n = 7310). Patients with multiple risk factors, such as prior aortic surgery and emergent surgery, had a 3-year reintervention rate 72%, (n = 32). Modifiable factors including EVR graft manufacturer or supra-renal fixation were not associated with reintervention (P = 0.76 and 0.79 respectively).

CONCLUSIONS

All patients retain a high likelihood of reintervention after EVR, but clinical factors at the time of repair can predict those at highest risk.

Postoperative imaging follow-up at 2 years as a predictor of long-term outcomes after endovascular aneurysm repair

OBJECTIVE

Lifelong imaging follow-up remains the reference standard after endovascular aneurysm repair (EVAR). Because the number of EVARs has been increasing, an individually optimized follow-up protocol is desirable. The aim of the present study was to investigate the possibility of creating such a protocol by evaluating patients' follow-up images and to compare the findings with their freedom from reintervention and abdominal aortic aneurysm (AAA) rupture.

METHODS

From 2000 to 2010, 282 patients with an AAA had undergone elective EVAR with the Zenith stent-graft. The patients were followed up annually until the end of 2019. The patients were categorized into two groups according to the presence of any endoleak or sac shrinkage at 2 years. Group A included those with no detectable endoleak plus aneurysm sac shrinkage of ≥5 mm (n = 137; 63%), and group B included those with any type of endoleak and/or no significant aneurysm sac shrinkage (<5 mm; n = 82; 37%).

RESULTS

The mean follow-up was 83 months (range, 0-229 months), and the overall survival at 2 years was 84% (n = 237). No significant difference was found in overall survival between groups A and B (P = .73). However, a significant difference was found in freedom from AAA rupture at 12 years, favoring group A (group A, 100%; group B, 91%; P = .002). Furthermore, in group A, the freedom from reintervention was 95% at 12 years compared with only 31% in group B (P < .001). The sensitivity of the categorization was 89% and the specificity was 74% for the finding of a complication requiring a reintervention during long-term follow-up.

CONCLUSIONS

Patients without an endoleak and a reduction of ≥5 mm in aneurysm size at 2 years had significantly fewer late reinterventions and ruptures during long-term follow-up compared with their counterparts using the Zenith stent-graft (Cook Medical, Bloomington, Ind). This finding suggests that, for these patients, the follow-up interval can be personalized and safely extended after 2 years.

Difficult diagnosis and management of a complicated Nellix graft infection

An 81-year-old man, with a complex vascular surgical history, presents with sepsis from an infected Nellix stent-graft. He required an urgent laparotomy, explantation of the graft, and extra-anatomical repair. Although now widely used for this indication, the preoperative 18F-fluorodeoxyglucose positron emission tomography/computed tomography was nondiagnostic for his stent-graft infection. We describe our management of a complicated Nellix graft infection and discuss the utility of positron emission tomography/computed tomography for stent-graft infections.

Statin use, development of sarcopenia, and long-term survival after endovascular aortic repair

OBJECTIVE

Statin therapy, associated with improved short-term survival after treatment of abdominal aortic aneurysms, may also predispose to muscle side effects. Evidence on statin-related sarcopenia is limited mainly to muscle function, and it is subject to several sources of bias. In the long term, postoperative development of sarcopenia is linked to mortality after endovascular repair (EVAR). We investigated statin use and long-term postoperative mortality after EVAR in relation to objective measurable markers of sarcopenia (psoas muscle surface area and density).

METHODS

Altogether 216 abdominal aortic aneurysm patients treated with EVAR between 2006 and 2014 at Tampere University Hospital (Finland) were retrospectively studied. Psoas muscle parameters at the L3 level were evaluated from baseline and mainly 1- to 3-year follow-up computed tomography studies. Cox regression was used to study the association between statin medication, psoas muscle changes, and all-cause mortality.

RESULTS

The majority of patients were male (87%), and the mean age was 77.7 years (standard deviation, 7.4). The median duration of follow-up was 6.3 years (interquartile range, 3.5) with a total mortality of 54.2% (n = 117). Regardless of a higher burden of comorbidities, statin users (n = 119) had lower mortality when compared with nonusers (multivariable hazard ratio [HR]: 0.69, 95% confidence interval: 0.48-0.99, P = .048). Furthermore, statin use was not associated with inferior muscle parameter values, and the relative change in psoas muscle area was actually lower in statin users compared with nonusers (-15.7% and -21.1%, P < .046).

CONCLUSIONS

Statin use is associated with lower long-term mortality among patients undergoing EVAR without predisposing to increased sarcopenia.

Risk assessment in aortic aneurysm repair by medical specialists versus the American College of Surgeons National Surgical Quality Improvement Program risk calculator outcomes

Objective

The aim of this online clinical vignette-based survey study was to compare risk assessments by vascular surgeons, anaesthesiologists and interventional radiologists involved in treating patients with aortic aneurysms in the Netherlands with the NSQIP risk calculator outcomes.

Methods

Participants, recruited using purposive sampling, provided their estimation of the likelihood of postoperative complications and events following aortic surgery in five fictional cases. These cases were subsequently scored using the NSQIP calculator. The risk assessments were statistically analysed using the ANOVA and student t-test.

Results

All participating specialists i.e. twelve vascular surgeons, ten interventional radiologists and ten anaesthesiologists completed the survey. In the vast majority of outcomes and vignettes, no significant differences were found between various specialists, whereas significant differences were found between the NSQIP risk calculator outcomes and the combined risk assessments of the specialists. Overall, specialist risk assessments differ from the NSQIP, but neither particularly higher nor lower compared to the risk calculator.

Conclusions

Risk assessment by vascular surgeons, anaesthesiologists and interventional radiologists differs significantly with NSQIP risk calculator outcomes, within the framework of both endovascular and open aortic aneurysm repair. Based on these results, implementing the NSQIP risk calculator in preoperative workup could be of added value in both patient planning as well as adequately informing patients for obtaining consent.

Factors affecting the occurrence of proximal endoleak after endovascular abdominal aortic repair for abdominal aneurysms

Objective

This retrospective study was performed to assess the clinical and radiological variables associated with proximal type IA endoleak (EL) in patients treated with elective endovascular repair for abdominal aortic aneurysms.

Methods

The chi-square test, t-test, and logistic regression analysis were performed as appropriate. A P value of <0.05 was considered statistically significant.

Results

The data of 79 patients were analyzed. No mortality occurred. During follow-up (median, 28.5 months; interquartile range, 12.8–43.0 months), 10 patients developed type IA EL. In the logistic regression analysis, undersizing of the endograft diameter by <10% significantly affected the occurrence of type IA EL. When the diameter was used for measurements, less oversizing was significantly associated with a higher risk of type IA EL. When the area was used for measurements, oversizing of >20% significantly affected the occurrence of type IA EL.

Conclusion

When sizing endografts, a discrepancy was noted between the measurements of the diameter and area of the proximal neck. The area might represent a more accurate measurement than the axial diameter to optimize the proximal sealing and lower the risk of developing type IA EL.

Use of carbon dioxide for therapeutic decision-making in endoleaks: a case report

Endovascular aneurysm repair is currently the most frequently treatment modality for infrarenal aortic aneurysms. Endoleaks are the most common cause of reintervention after endovascular aneurysm repair. It is often unclear which type of endoleak is the correct diagnose, making the treatment decision difficult. We report the case of a 72-year-old man with an endoleak two years after endovascular aneurysm repair. Images suggested a type III endoleak, but this was not confirmed by contrast aortography. We proceeded with the investigation using aortography with carbon dioxide and observed a type IA endoleak. This was successfully treated by implantation of a proximal cuff. A review of the literature shows that the role of carbon dioxide in endoleak management is still unclear. We present a case in which carbon dioxide was essential to both diagnosis and therapeutic decision-making in a type IA endoleak.

Secondary Interventions and Long-term Follow-up after Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

Early morbidity and mortality are low after endovascular abdominal aneurysm repair (EVAR), but secondary interventions and late complications are common. The aim of the present multicenter cohort study is to detail the frequency and indication for interventions after EVAR and the impact on long-term survival.

METHODS

A retrospective multicenter cohort study of secondary interventions after elective EVAR for an infrarenal abdominal aortic aneurysm was conducted. Consecutive patients (n = 349) undergoing EVAR between January 2007 and January 2012 were analyzed, with long-term follow-up until December 2018. Those requiring intervention were classified in accordance with the indications and specific nature of the intervention and treatment. The primary study end point was overall survival classified for patients with and without intervention. Kaplan-Meier analysis was used to estimate overall survival for those who did and who did not undergo secondary interventions. Univariable and multivariable Cox regression were performed to identify independent variables associated with mortality.

RESULTS

Some 56 patients (16%) underwent 72 secondary interventions after EVAR during a median (interquartile range) follow-up period of 53.2 months (60.1). Some 45 patients (80.4%) underwent one intervention. Indications for intervention included mainly endograft kinking/outflow obstruction and type II endoleak. An endovascular technique was used in 40.3% of interventions. Median time to secondary intervention was 24.1 months. In 93 patients with abnormalities on imaging, no intervention was performed mainly because the abnormality had disappeared on follow-up imaging (43%). Kaplan-Meier curves showed no difference in survival for patients with and without secondary interventions (P = 0.153). Age (hazard ratio [HR]: 1.089, 95% confidence interval [CI]: 1.063-1.116), ASA classification (ASA III, IV HR: 1.517, 95% CI: 1.056-2.178) were significantly related to mortality.

CONCLUSIONS

Secondary intervention rates are still considerable after EVAR. Endograft kinking/outflow obstruction and endoleak type II are the most common indications for a secondary intervention. Secondary interventions did not adversely affect long-term overall survival after EVAR.

Medicare costs for endovascular abdominal aortic aneurysm treatment in the Vascular Quality Initiative

BACKGROUND

Reintervention after endovascular repair (EVR) of abdominal aortic aneurysms is common. However, the cumulative financial impact of reintervention after EVR on a national scale is poorly defined. Our objective was to describe the cost to Medicare for aneurysm treatment (EVR plus reinterventions) among a cohort of patients with known follow-up for 5 years after repair.

METHODS

We identified patients who underwent EVR within the Vascular Quality Initiative who were linked to their respective Medicare claims file (n = 13,995). We excluded patients who underwent EVR after September 30, 2010, and those who had incomplete Medicare coverage (n = 12,788). The remaining cohort (n = 1207) had complete follow-up until death or 5 years (Medicare data available through September 30, 2015). We then obtained and compiled the corresponding Medicare reimbursement data for the index EVR hospitalization and all subsequent reinterventions.

RESULTS

We studied 1207 Medicare patients who underwent EVR and had known follow-up for reinterventions for 5 years. The mean age was 76.2 years (±7.1 years), 21.6% of patients were female, and 91.1% of procedures were elective. The Kaplan-Meier reintervention rate at 5 years was 18%. Among patients who underwent reintervention, 154 (73.7%) had a single reintervention, 40 (19.1%) had two reinterventions, and 15 (7.2%) had three or more reinterventions. The median cost to Medicare for the index EVR hospitalization was $25,745 (interquartile range, $21,131-$28,774). The median cost for subsequent reinterventions was $22,165 (interquartile range, $17,152-$29,605). The cumulative cost to Medicare of aneurysm treatment (EVR plus reinterventions) increased in a stepwise fashion among patients who underwent multiple reinterventions, with each reintervention being similar in cost to the index EVR.

CONCLUSIONS

The overall cost incurred by Medicare to reimburse for each reintervention after EVR is roughly the same as for the initial procedure itself, meaning that Medicare cost projections would be greater than $100,000 for any individual who undergoes an EVR with three reinterventions. The long-term financial impact of EVR must be considered by surgeons, patients, and healthcare systems alike as these cumulative costs may hinder the fiscal viability of an EVR-first therapeutic approach and highlight the need for judicious patient selection paradigms.

Physiological Appearance of Hybrid FDG-Positron Emission Tomography/Computed Tomography Imaging Following Uncomplicated Endovascular Aneurysm Sealing Using the Nellix Endoprosthesis

Purpose: To investigate the physiological uptake of hybrid fluorine-18-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) before and after an uncomplicated endovascular aneurysm sealing (EVAS) procedure as a possible tool to diagnose EVAS graft infection and differentiate from postimplantation syndrome. Materials and Methods: Eight consecutive male patients (median age 78 years) scheduled for elective EVAS were included in the prospective study (ClinicalTrials.gov identifier NCT02349100). FDG-PET/CT scans were performed in all patients before the procedure and 6 weeks after EVAS. The abdominal aorta was analyzed in 4 regions: suprarenal, infrarenal neck, aneurysm sac, and iliac. The following parameters were obtained for each region: standard uptake value (SUV), tissue to background ratio (TBR), and visual examination of FDG uptake to ascertain its distribution. Demographic data were obtained from medical files and scored based on reporting standards. Results: Visual examination showed no difference between pre- and postprocedure FDG uptake, which was homogenous. In the suprarenal region no significant pre- and postprocedure differences were observed for the SUV and TBR parameters. The infrarenal neck region showed a significant decrease in the SUV and no significant decrease in the TBR. The aneurysm sac and iliac regions both showed a significant decrease in SUV and TBR between the pre- and postprocedure scans. Conclusion: Physiological FDG uptake after EVAS was stable or decreased with regard to the preprocedure measurements. Future research is needed to assess the applicability and cutoff values of FDG-PET/CT scanning to detect endograft infection after EVAS.

Elective late open conversion after endovascular aneurysm repair is associated with comparable outcomes to primary open repair of abdominal aortic aneurysms

OBJECTIVE

Three of four patients with infrarenal abdominal aortic aneurysm are now treated with endovascular aneurysm repair (EVAR). The incidence of secondary procedures and surgical conversions is increasing for a population theoretically unfit for open surgery. The indications and outcomes of late open surgical conversions after EVAR in a high-volume tertiary vascular unit are reported.

METHODS

This retrospective single-center study includes all patients who underwent a late open conversion between January 1996 and July 2018. Data were collected from records on patient demographics, operative indications, surgical strategy, perioperative outcomes, and medium-term survival.

RESULTS

Sixty-two consecutive patients (88.7% male) with a mean age of 77.5 years are included. The median duration since index EVAR was 38.5 months; 65% of stent grafts requiring late open conversion had suprarenal fixation. Indications included 22.6% type IA, 16.1% type IB, and 45.2% type II endoleaks; 12.9% graft thrombosis; and 14.5% endoprosthesis infection. Complete endograft explantation was performed in 37.1% of patients and a partial explantation in 54.8%, whereas 8.1% of stent grafts were wholly preserved in situ. Overall 30-day mortality was 12.9% (n = 8) in the cohort and 2.7% for elective patients. The all-cause morbidity rate was 40.1%, and the median length of hospital stay was 9 days. After follow-up of 28.4 months (range, 1.8-187.3 months), all-cause survival was 58.8%. Avoidance of aortic clamping (P = .006) and elective procedures (P = .019) were associated with a significant reduction in the length of hospital stay. Moreover, the 30-day mortality (P = .002), occurrence of postoperative renal dysfunction (P = .004), and intestinal ischemia (P = .017) were increased in the emergency setting. Excluding cases with rupture or infection, survival estimates were 97%, 97%, and 71% at 1 year, 2 years, and 5 years, respectively.

CONCLUSIONS

Technically more complex than primary open surgery, late open conversion is a procedure that generates an acceptable perioperative risk when it is performed in a high-volume aortic surgical center. Elective open conversion is associated with excellent early and late outcomes. Endograft preservation strategies decrease perioperative morbidity.

Outcomes of Late Open Conversion after Endovascular Abdominal Aneurysm Repair

Objective: To review our experience with a late open conversion as a final option for an endograft infection and aneurysm expansion after endovascular aneurysm repair (EVAR), especially in endoleaks for which radiological intervention is impossible. Materials and Methods: In this retrospective study, 13 late open conversions out of 513 consecutive patients treated by EVAR were analyzed. Indications for an open conversion were aneurysm enlargement, including all endoleaks, endograft migration, and endograft infection. The patients' data on demographics, operative details, and outcomes were reviewed. Results: Indications for a late open conversion included endoleaks, infection, and migration in 61.5%, 30.8%, and 7.7% of patients, respectively. The median interval from the initial EVAR was 32.4 months. Complete endograft explantation was performed in four patients with an endograft infection. In endoleak cases, the endograft was partially preserved and a neo-neck was used. Sacotomy and branch ligation were performed in one case. One major operative complication was an aortic injury during infrarenal aortic cross-clamping in an endograft migration case. There was no operative mortality. Conclusion: A late open conversion after EVAR is valuable as a final option. The aortic cross-clamp site, especially in endograft migration cases, should be carefully considered. To avoid aneurysm-related events, graft replacement is recommended, if possible.

Five-year reintervention after endovascular abdominal aortic aneurysm repair in the Vascular Quality Initiative

OBJECTIVE

Patients who undergo endovascular abdominal aortic aneurysm repair (EVR) remain at risk for reintervention and rupture. We sought to define the 5-year rate of reintervention and rupture after EVR in the Vascular Quality Initiative (VQI).

METHODS

We identified all patients in the VQI who underwent EVR from 2003 to 2015. We linked patients in the VQI to Medicare claims for long-term outcomes. We stratified patients on baseline clinical and procedural characteristics to identify those at risk for reintervention. Our primary outcomes were 5-year rates of reintervention and late aneurysm rupture after EVR. We assessed these with Kaplan-Meier survival estimation.

RESULTS

We studied 12,911 patients who underwent EVR. The mean age was 75.5 years, 79.9% were male, 3.9% were black, and 89.1% of operations were performed electively. The 5-year rate of reintervention for the entire cohort was 21%, and the 5-year rate of late aneurysm rupture was 3%. Reintervention rates varied across categories of EVR urgency. Patients who underwent EVR electively had the lowest 5-year rate of reintervention at 20%. Those who underwent surgery for symptomatic aneurysms had higher rates of reintervention at 25%. Patients undergoing EVR emergently for rupture had the highest rate of reintervention, 27% at 4 years (log-rank across the three groups, P < .001). Black race and aneurysm size of 6.0 cm or greater were associated with significantly elevated reintervention rates (black, 31% vs white, 20% [log-rank, P < .001]; aneurysm size 6.0 cm or greater, 27% vs all others, <20% [log-rank, P < .001]). There were no significant associations between age or gender and the 5-year rate of reintervention.

CONCLUSIONS

More than one in five Medicare patients undergo reintervention within 5 years after EVR in the VQI; late rupture remains low at 3%. Black patients, those with large aneurysms, and those who undergo EVR urgently and emergently have a higher likelihood of adverse outcomes and should be the focus of diligent long-term surveillance.

New Conception of Relining in the Endovascular Aneurysm Sealing Era: A Monocentric Case Series Study

Over 20 years from the first endovascular aortic repair, endoleaks still represent a common problem, even with newer endograft generation. Numerous procedures can be adopted to manage these complications; relining of the endoprosthesis is a rational technique to treat type III and IV endoleaks. The absence of dedicated materials for these procedures forces the vascular surgeon to perform complex hybrid or endovascular interventions. In this case report, we aimed to evaluate our relining experience using the Nellix device in 5 consecutive cases.

Late open conversions after endovascular abdominal aneurysm repair in an urgent setting

OBJECTIVES

We report a multicenter experience of urgent late open conversion (LOC), with the goal of identifying the mode of presentation, technical aspects, and outcomes of this cohort of patients.

METHODS

A retrospective analysis of endovascular aneurysm repair (EVAR) requiring LOC (>30 days after implantation) from 1996 to 2016 in six vascular centers was performed. Patients with aneurysm rupture or other conditions requiring urgent surgery (<24 hours) were included. Patient demographics, time interval between EVAR and LOC, endograft characteristics, previous attempts at endovascular correction, indications, operative technique, 30-day mortality and morbidity, and long-term survival were analyzed.

RESULTS

There were 42 patients (88.1% men; mean age, 75.8 ± 9.0 years) included. Among the 42 explanted grafts, 33 were bifurcated, 1 tube, 6 aortouni-iliac, and 2 side-branch devices. Suprarenal fixation was present in 78.6%. Twelve patients (28.6%) underwent endovascular reintervention before LOC. Indications for urgent LOC were aneurysm rupture in 24 of the 42 cases (57.1%), endograft infection in 11 (26.2%), endoleak associated with aneurysm growth and pain in 6 (14.3%), and recurrent endograft thrombosis in 2 (4.8%). The proximal aortic cross-clamping site was infrarenal in 38.1% of cases, suprarenal in 19.1%, and supraceliac in 42.9%. Complete removal of the endograft was performed in 32 patients (76.2%) and partial removal in 10 (proximal preservation in 7 of 10). Reconstructions were performed with Dacron grafts in 33 of the 42 cases, cryopreserved arterial allografts in 5, and endograft removal associated with prosthetic axillobifemoral bypass in 4. The 30-day mortality was 23.8%; hemorrhagic shock was an independent risk factor of early mortality (odds ratio, 10.5; 95% confidence interval, 1.5-73.7; P = .018). During a mean follow-up of 23.9 ± 36.0 months, two late aneurysm-related deaths occurred. The estimated 1- and 5-year survival rates were 62.1% and 46.1%, respectively.

CONCLUSIONS

Urgent LOC after EVAR are associated with high postoperative mortality rates and poor long-term survival. Further studies are necessary to define the timing and the best treatment option for failing EVAR.

Identifying and addressing the limitations of EVAR technology

INTRODUCTION

Endovascular aortic repair (EVAR) has improved over the last two decades. Approximately 80% of the patients presenting with an abdominal aortic aneurysm (AAA) is nowadays primarily treated with EVAR.

AREAS COVERED

In this review, the differences between endovascular and open repair, the clinical characteristics needed for EVAR, the role of clinical imaging and the developments in EVAR technology will be discussed. Early mortality is lower in EVAR as compared to open repair, whereas this benefit is lost after 3 years postoperatively. EVAR comes with a high reintervention rate, with endoleak being the most important predictive factor for reintervention. Expanding technical possibilities have allowed surgeons to choose from a palate of endovascular approaches in aneurysm patients with challenging anatomies.

EXPERT COMMENTARY

Although EVAR has taken a giant leap forward in development, the new developments have seemed to surpass the long-term limitations with older devices. It is important to start focusing on the current limitations of EVAR, in particular the durability of devices in the human variable anatomic and dynamic environment.

Significance and Risk Factors for Intraprosthetic Mural Thrombus in Abdominal Aortic Endografts: A Systematic Review and Meta-analysis

BACKGROUND

The detection of intraprosthetic thrombus (IPT) deposits is a common finding during follow-up for endovascular abdominal aneurysm repair (EVAR); however, its clinical significance is still debated. The aim of this study was to determine if IPT represents a risk factor for thromboembolic events (TEs; endograft or limb thrombosis, or distal embolization) after EVAR.

METHODS

A systematic review of English literature was undertaken until November 2017. Studies providing 2-group comparison (patients with IPT development on postoperative computed tomography angiography versus patients without IPT) with extractable outcome data (TE related to IPT and/or risk factors for IPT development) were included. Meta-analysis was performed when comparative data were given in 2 or more articles.

RESULTS

Five single-center studies (808 patients) were analyzed. IPT detection at any time during follow-up occurred in 20.8% (168/808) of patients. Extractable data for postoperative TE were available in 4 studies (613 patients): on comparative meta-analysis, IPT was not significantly associated with TE occurrence during follow-up (odds ratio 2.25, 95% confidence interval [CI] 0.50-10.1; P = 0.29). IPT is generally detected during the first year after EVAR (maximum reported median: 12 months, range: 1.2-23). Polyester graft material (odds ratio 2.34, 95% CI 1.53-3.58; P < 0.001) and aorto-uni-iliac configuration of the endograft (odds ratio 3.27, 95% CI 1.66-6.44; P = 0.001) were confirmed as risk factors for IPT formation on meta-analysis. The literature systematic review suggests that IPT formation may be also associated with long main bodies and large necks.

CONCLUSIONS

IPT detection on postoperative computed tomography angiography was not significantly associated with the occurrence of TE over time. The aorto-uni-iliac configuration and the use of polyester fabric for endografts were confirmed as risk factors for IPT development.