Long-term postplacement cost after endovascular aneurysm repair

Early Financial Outcomes of Physician Modified Endograft Programs Are Dictated by Device Cost

INTRODUCTION

Physician-modified endografts (PMEGs) have been used for repair of thoracoabdominal aortic aneurysms (TAAAs) for 2 decades with good outcomes but limited financial data. This study compared the financial and clinical outcomes of PMEGs to the Cook Zenith-Fenestrated (ZFEN) graft and open surgical repair (OSR).

METHODS

A retrospective review of financial and clinical data was performed for all patients who underwent endovascular or OSR of juxtarenal aortic aneurysms and TAAAs from January 2018 to December 2022 at an academic medical center. Clinical presentation, demographics, operative details, and outcomes were reviewed. Financial data was obtained through the institution's finance department. The primary end point was contribution margin (CM).

RESULTS

Thirty patients met inclusion criteria, consisting of twelve PMEG, seven ZFEN, and eleven open repairs. PMEG repairs had a total CM of -$110,000 compared to $18,000 for ZFEN and $290,000 for OSR. Aortic and branch artery implants were major cost-drivers for endovascular procedures. Extent II TAAA repairs were the costliest PMEG procedure, with a total device cost of $59,000 per case. PMEG repairs had 30-d and 1-y mortality rates of 8.3% which was not significantly different from ZFEN (0.0%, P = 0.46; 0.0%, P = 0.46) or OSR (9.1%, P = 0.95; 18%, P = 0.51). Average intensive care unit and hospital stay after PMEG repairs were comparable to ZFEN and shorter than OSR.

CONCLUSIONS

Our study suggests that PMEG repairs yield a negative CM. To make these cases financially viable for hospital systems, device costs will need to be reduced or reimbursement rates increased by approximately $8800.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Cost of Follow Up After Endovascular Abdominal Aortic Aneurysm Repair in Patients With an Initial Post-Operative Computed Tomography Angiogram Without Abnormalities

OBJECTIVE

The Observing a Decade of Yearly Standardised Surveillance in EVAR patients with Ultrasound or CT Scan (ODYSSEUS) study was conducted to assess differences in outcomes of patients with continued or discontinued yearly follow up after endovascular abdominal aortic aneurysm repair (EVAR). Earlier results of this study showed that discontinued follow up was not associated with poor outcomes. Therefore, an incremental cost analysis and budget impact analysis of de-implementation of yearly imaging following EVAR was performed.

METHODS

In total, 1 596 patients from the ODYSSEUS study were included. The expected cost savings were assessed if yearly imaging was reduced in patients with a post-operative computed tomography angiogram without abnormalities made around 30 days after EVAR. Costs were derived from the Dutch costs manual, benchmark cost prices, and literature review. Costs were expressed in euros (€) and displayed at 2019 prices. Sensitivity analysis was performed by varying costs.

RESULTS

A difference of 24% in cost was found between patients with continued and discontinued imaging follow up. The cost per patient was €1 935 in the continued group vs. €1 603 per patient in the discontinued group at five years post-EVAR, with a mean difference of €332 (95% bias corrected and accelerated bootstrap confidence interval -741 to 114). De-implementation of yearly imaging would result in an annual nationwide cost saving of €678 471. Sensitivity analysis with variation in adherence rates, imaging, or secondary intervention costs resulted in a saving of at least €271 388 per year.

CONCLUSION

This study provided an in depth analysis of hospital costs for post-EVAR patients in the Netherlands with a modest impact on the Dutch healthcare budget.

Longer follow-up intervals following EVAR are safe and appropriate after marked aneurysm sac regression

BACKGROUND

Abdominal aortic aneurysm (AAA) shrinkage after endovascular aortic aneurysm repair (EVAR) is a surrogate marker for successful exclusion. Our study characterized aneurysm sac remodeling after EVAR to identify a pattern that may be associated with benign AAA behavior and would safely allow a less rigorous follow-up regimen after EVAR.

METHODS

Elective infrarenal EVARs performed between 2008 and 2011 at our institution were retrospectively reviewed. AAA sac diameters using the minor axis measurement from ultrasound imaging or computer tomography angiogram imaging were compared with the baseline diameter from the 1-month postoperative computer tomography angiogram. The primary outcome was a composite of freedom from postoperative reintervention or rupture. We compared those with AAA sacs who regressed to predefined minimum diameter thresholds with those who did not. Outcomes were plotted with Kaplan-Meier curves and compared using log-rank testing and Fine-Gray regression using death as a competing risk, clustered on graft type. For patients whose AAA reached the minimum sac diameter, landmark analysis evaluated ongoing size changes including further regression and sac re-expansion.

RESULTS

A total of 540 patients (aged 75.1 ± 8.2 years; 82.0% male) underwent EVAR with an average preoperative AAA size of 55.2 ± 11.5 mm. The median postoperative follow-up was 5.3 years (interquartile range, 1.4-8.7 years) during which 64 patients underwent reintervention and 4 ruptured. AAA sac regression to ≤40 mm in diameter was associated with improved freedom from reintervention or rupture overall (log-rank, P < .01), which was maintained after controlling for the competing risk of death (P < .01). In 376 patients (70%) whose aneurysm sac remained >40 mm, 99 reinterventions were performed on 63 patients. Of 166 (31%) patients whose sac regressed to ≤40 mm, only 1 patient required a reintervention, and no one ruptured. The mean time to a diameter of ≤40 mm was 2.3 ± 1.9 years. Only eight patients (5%) developed sac re-expansion to >45 mm; all but two occurred at least 3 years after initially regressing to ≤40 mm.

CONCLUSIONS

In long-term follow-up, patients whose minimum AAA sac diameter regressed ≤40 mm after EVAR experienced a very low rate of reintervention, rupture, or sac re-expansion. Most sac re-expansion occurred at least 3 years after reaching this threshold and did not result in clinical events. Increasing follow-up frequency up to 3-year intervals once the AAA sac regresses to 40 mm would carry minimal risk of aneurysm-related morbidity.

Color Doppler ultrasound for surveillance following EVAR as the primary tool

OBJECTIVE

As aneurysm-related events and rupture is not eliminated, postoperative lifelong surveillance is mandatory after endovascular aneurysm repair (EVAR). For surveillance colored Doppler ultrasound (CDUS) is a standard method of noninvasive evaluation having the advantages of availability, cost-effectiveness, and lack of nephrotoxicity and radiation. We evaluated CDUS for primary surveillance tool after elective EVAR by comparing with computerized tomography.

METHODS

Between January 2018 and March 2020, 84 consecutive post-EVAR patients were evaluated. First, CDUS was performed by two Doppler operators from the Radiology Department and then computed tomographic angiography (CTA) was performed. The operators were blind to CTA reports. A reporting protocol was organized for endoleak detection and largest aneurysm diameter.

RESULTS

Among 84 patients, there were 11 detected endoleaks (13.1%) with CTA and seven of them was detected with CDUS (r = .884, p < .001). All Type I and III endoleaks were detected perfectly. There is an insufficiency in detecting low flow by CDUS. Eliminating this frailty, there was a strong correlation of aneurysm sac diameter measurement between CTA and CDUS (r = .777, p < .001). The sensitivity and specificity of CDUS was 63.6% and 100%, respectively. The accuracy was 95.2%. Positive and negative predictive values were 100% and 94.8%. Bland-Altman analysis and linear regression analysis showed no proportional bias (mean difference of 1.5 ± 2.2 mm, p = .233).

CONCLUSIONS

For surveillance, CDUS promises accurate results without missing any potential complication requiring intervention as Type I or III endoleak. Lack of detecting Type II endoleaks may be negligible as sac enlargement was the key for reintervention in this situation and CDUS has a remarkably high correlation with CTA in sac diameter measurement. CDUS may be a primary surveillance tool for EVAR and CTA will be reserved in case of aneurysm sac enlargement, detection of an endoleak, inadequate CDUS, or in case of unexplained abdominal symptomatology. By this way we not only avoid ionizing radiation and nephrotoxic agents, but also achieve cost saving issue also.

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.

Optimizing Surveillance and Re-intervention Strategy Following Elective Endovascular Repair of Abdominal Aortic Aneurysms

BACKGROUND

EVAR for abdominal aortic aneurysm has an initial survival advantage over OR, but more frequent complications increase costs and long-term aneurysm-related mortality. Randomized controlled trials of EVAR versus OR have shown EVAR is not cost-effective over a patient's lifetime. However, in the EVAR-1 trial, postoperative surveillance may have been sub-optimal, as the importance of sac growth as a predictor of graft failure was overlooked.

METHODS

Real-world data informed a discrete event simulation model of postoperative outcomes following EVAR. Outcomes observed EVAR-1 were compared with those from 5 alternative postoperative surveillance and re-intervention strategies. Key events, quality-adjusted life years and costs were predicted. The impact of using complication and rupture rates from more recent devices, imaging and re-intervention methods was also explored.

RESULTS

Compared with observed EVAR-1 outcomes, modeling full adherence to the EVAR-1 scan protocol reduced abdominal aortic aneurysm (AAA) deaths by 3% and increased elective re-interventions by 44%. European Society re-intervention guidelines provided the most clinically effective strategy, with an 8% reduction in AAA deaths, but a 52% increase in elective re-interventions. The cheapest and most cost-effective strategy used lifetime annual ultrasound in primary care with confirmatory computed tomography if necessary, and reduced AAA-related deaths by 5%. Using contemporary rates for complications and rupture did not alter these conclusions.

CONCLUSIONS

All alternative strategies improved clinical benefits compared with the EVAR-1 trial. Further work is needed regarding the cost and accuracy of primary care ultrasound, and the potential impact of these strategies in the comparison with OR.

Predicting risk of rupture and rupture-preventing reinterventions following endovascular abdominal aortic aneurysm repair

Background

Clinical and imaging surveillance practices following endovascular aneurysm repair (EVAR) for intact abdominal aortic aneurysm (AAA) vary considerably and compliance with recommended lifelong surveillance is poor. The aim of this study was to develop a dynamic prognostic model to enable stratification of patients at risk of future secondary aortic rupture or the need for intervention to prevent rupture (rupture‐preventing reintervention) to enable the development of personalized surveillance intervals.

Methods

Baseline data and repeat measurements of postoperative aneurysm sac diameter from the EVAR‐1 and EVAR‐2 trials were used to develop the model, with external validation in a cohort from a single‐centre vascular database. Longitudinal mixed‐effects models were fitted to trajectories of sac diameter, and model‐predicted sac diameter and rate of growth were used in prognostic Cox proportional hazards models.

Results

Some 785 patients from the EVAR trials were included, of whom 155 (19·7 per cent) experienced at least one rupture or required a rupture‐preventing reintervention during follow‐up. An increased risk was associated with preoperative AAA size, rate of sac growth and the number of previously detected complications. A prognostic model using predicted sac growth alone had good discrimination at 2 years (C‐index 0·68), 3 years (C‐index 0·72) and 5 years (C‐index 0·75) after operation and had excellent external validation (C‐index 0·76–0·79). More than 5 years after operation, growth rates above 1 mm/year had a sensitivity of over 80 per cent and specificity over 50 per cent in identifying events occurring within 2 years.

Conclusion

Secondary sac growth is an important predictor of rupture or rupture‐preventing reintervention to enable the development of personalized surveillance intervals. A dynamic prognostic model has the potential to tailor surveillance by identifying a large proportion of patients who may require less intensive follow‐up.

Potential to tailor surveillance

Episode-based cost reduction for endovascular aneurysm repair

OBJECTIVE

Effective strategies to reduce costs associated with endovascular aneurysm repair (EVAR) remain elusive for many medical centers. In this study, targeted interventions to reduce inpatient EVAR costs were identified and implemented.

METHODS

From June 2015 to February 2016, we analyzed the EVAR practice at a high-volume academic medical center to identify, to rank, and ultimately to reduce procedure-related costs. In this analysis, per-patient direct costs to the hospital were compared before (September 2013-May 2015) and after (March 2016-January 2017) interventions were implemented. Improvement efforts concentrated on three categories that accounted for a majority of costs: implants, rooming costs, and computed tomography scans performed during the index hospitalization.

RESULTS

Costs were compared between 141 EVAR procedures before implementation (PRE period) and 47 EVAR procedures after implementation (POST period). Based on data obtained through the Society for Vascular Surgery EVAR Cost Demonstration Project, it was determined that implantable device costs were higher than those at peer institutions. New purchasing strategies were implemented, resulting in a 30.8% decrease in per-case device costs between the PRE and POST periods. Care pathways were modified to reduce use of and costs for computed tomography scans obtained during the index hospitalization. Compared with baseline, per-case imaging costs decreased by 92.9% (P < .001), including a 99.0% (P = .001) reduction in postprocessing costs. Care pathways were also implemented to reduce preprocedural rooming for patients traveling long distances the day before surgery, resulting in a 50% decrease in utilization rate (35.4% PRE to 17.0% POST; P = .021), without having a significant impact on median postprocedural length of stay (PRE, 2 days [interquartile range, 1-11 days]; POST, 2 days [1-7 days]; P = .185). Medication costs also decreased by 38.2% (P < .001) as a hospital-wide effort.

CONCLUSIONS

Excessive costs associated with EVAR threaten the sustainability of these procedures in health care organizations. Targeted cost reduction efforts can effectively reduce expenses without compromising quality or limiting patients' access.

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

BACKGROUND

Current surveillance protocols after endovascular aneurysm repair (EVAR) are ineffective and costly. Stratifying surveillance by individual risk of reintervention requires an understanding of the factors involved in developing post-EVAR complications. This systematic review assessed risk factors for reintervention after EVAR and proposals for stratified surveillance.

METHODS

A systematic search according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed using EMBASE and MEDLINE databases to identify studies reporting on risk factors predicting reintervention after EVAR and proposals for stratified surveillance.

RESULTS

Twenty-nine studies reporting on 39 898 patients met the primary inclusion criteria for reporting predictors of reintervention or aortic complications with or without suggestions for stratified surveillance. Five secondary studies described external validation of risk scores for reintervention or aortic complications. There was great heterogeneity in reporting risk factors identified at the pre-EVAR, intraoperative, and post-EVAR stages of treatment, although large preoperative abdominal aortic aneurysm diameter was the most commonly observed risk factor for reintervention after EVAR.

CONCLUSION

Existing data on predictors of post-EVAR complications are generally of poor quality and largely derived from retrospective studies. Few studies describing suggestions for stratified surveillance have been subjected to external validation. There is a need to refine risk prediction for EVAR failure and to conduct prospective comparative studies of personalized surveillance with standard practice.

Abdominal aortic aneurysm follow-up by shear wave elasticity imaging after endovascular repair in a canine model

OBJECTIVES

To investigate if shear wave imaging (SWI) can detect endoleaks and characterize thrombus organization in abdominal aortic aneurysms (AAAs) after endovascular aneurysm repair.

METHODS

Stent grafts (SGs) were implanted in 18 dogs after surgical creation of type I endoleaks (four AAAs), type II endoleaks (13 AAAs) and no endoleaks (one AAA). Color flow Doppler ultrasonography (DUS) and SWI were performed before SG implantation (baseline), on days 7, 30 and 90 after SG implantation, and on the day of the sacrifice (day 180). Angiography, CT scans and macroscopic tissue sections obtained on day 180 were evaluated for the presence, size and type of endoleaks, and thrombi were characterized as fresh or organized. Endoleak areas in aneurysm sacs were identified on SWI by two readers and compared with their appearance on DUS, CT scans and macroscopic examination. Elasticity moduli were calculated in different regions (endoleaks, and fresh and organized thrombi).

RESULTS

All 17 endoleaks (100 %) were identified by reader 1, whereas 16 of 17 (94 %) were detected by reader 2. Elasticity moduli in endoleaks, and in areas of organized thrombi and fresh thrombi were 0.2 ± 0.4, 90.0 ± 48.2 and 13.6 ± 4.5 kPa, respectively (P < 0.001 between groups). SWI detected endoleaks while DUS (three endoleaks) and CT (one endoleak) did not.

CONCLUSIONS

SWI has the potential to detect endoleaks and evaluate thrombus organization based on the measurement of elasticity.

KEY POINTS

• SWI has the potential to detect endoleaks in post-EVAR follow-up. • SWI has the potential to characterize thrombus organization in post-EVAR follow-up. • SWI may be combined with DUS in post-EVAR surveillance of endoleak.

Early experience with the new endovascular aneurysm sealing system Nellix: First clinical results after 50 implantations

Objective

In the present study, 50 EVAS procedures were evaluated in regard to primary (survival and technical success) and secondary (device-related complications) events of interest.

Methods

The single center study was conducted from July 2013 to August 2014 with prospective collection of the clinical data. The clinical results were controlled by CT angiography and contrast-enhanced ultrasound .

Results

The technical success was 98% and the 30-day mortality 4%. One (2%) patient died from multisystem organ failure and another patient from an intracranial bleeding, respectively. One patient (2%) suffered from a device-related aneurysm rupture. During early follow-up, one (2%) patient developed an endoleak type II, while three (6%) patients suffered from a partial endograft limb thrombosis. Overall, a secondary intervention was necessary in six (12%) patients.

Conclusions

With the Nellix EVAS system, a high primary technical success of 98% was achieved; one (2%) patient developed an endoleak type II which did not require secondary intervention. Those promising results are contrasted by a substantial rate of endograft limb thromboses (8%) and one (2%) intraoperative aneurysm rupture. Further studies are needed to assess the durability of the Nellix stentgraft and the occurrence of device-related complications.

C-reactive protein predicts aortic aneurysmal disease progression after endovascular repair

OBJECTIVES

This study aims to investigate the prognostic significance of the rate of variation of C-reactive protein (CRP) levels as a predictor of aneurysmal sac and neck expansion and, therefore, of aneurysm disease progression, in patients undergoing endovascular aneurysm repair (EVAR) in the absence of endoleaks.

METHODS

192 patients following non-emergency elective EVAR for asymptomatic infra-renal abdominal aorta aneurysm (AAA) were included after a six-month period after intervention to ensure the treatment success and absence of endoleaks. Expansion of aneurysm sac or neck after the six-month stabilization term occurred in 120 (63%) and 128 (67%) patients for a mean follow-up of 53±23 months.

RESULTS

The relative CRP plasma level gradient significantly differed between the subgroups of patients according to relative sac expansion quartiles (7%, 26%, 39%, and 61%; p<0.001). In the bivariate analysis, the aorta sac diameter expansion rate progressively increased in the subgroups determined by CRP gradient quartiles (-0.5±1%, 3.6±1%, 8±2%, 10±3%; p<0.01). The median (25th; 75th quartile) CRP level rise in "rapid expanders" patients (those above the median annual sac expansion rate of 5.7%) was 51% (37%; 67%) compared with 15% (3%; 28%) in "slow- or non-expanders" (p<0.001). The multivariate age-adjusted logistic model confirmed the variation of CRP level and neck length as the only factors independently associated to sac expansion (odds ratio 4.3; 95% CI: 2.3-7.9 and 1.7; 95% CI: 1.3-2.2, respectively).

CONCLUSION

There is a significant time-related association between AAA sac diameter enlargement and CRP plasma level gradient after EVAR in the absence of endoleaks, confirming the latter as a proper marker of aneurysm disease progression and rate of expansion in these patients.

Endovascular aortoiliac aneurysm repair: surgical progress through new treatment paradigms and innovative endograft design

Effective treatment for patients with an abdominal aortic aneurysm (AAA) began more than 50 years ago through the development of prosthetic grafts, which were used to replace aneurysmal segments of diseased arteries. Open surgical repair of AAAs became the gold standard for treating this disease. In 1999, two device manufacturers received US Food and Drug Administration approval for their endovascular aneurysm repair (EVAR) devices to treat selected patients with AAA. During the next 10 years, multiple other EVAR devices received US Food and Drug Administration approval, and, now, EVAR rivals open surgical repair as the standard for treating aortoiliac aneurysm disease. The purpose of this article is to outline advances in the device technology used for EVAR procedures, identify historical progress of treatment options, recognize complications after EVAR, describe improvements in device design, and specify related nursing implications.

Duplex Ultrasound versus Computed Tomography for the Postoperative Follow-Up of Endovascular Abdominal Aortic Aneurysm Repair. Where Do We Stand Now?

In the last decade, endovascular aneurysm repair (EVAR) has rapidly developed to be the preferred method for infrarenal abdominal aortic aneurysm repair in patients with suitable anatomy. EVAR offers the advantage of lower perioperative mortality and morbidity but carries the cost of device-related complications such as endoleak, graft migration, graft thrombosis, and structural graft failure. These complications mandate a lifelong surveillance of EVAR patients and their endografts. The purpose of this study is to review and evaluate the safety of color-duplex ultrasound (CDU) as compared with computed tomography (CT), based on the current literature, for post-EVAR surveillance. The post-EVAR follow-up modalities, CDU versus CT, are evaluated questioning three parameters: (1) accuracy of aneurysm size, (2) detection and classification of endoleaks, and (3) detection of stent-graft deformation. Studies comparing CDU with CT scan for investigation of post-EVAR complications have produced mixed results. Further and long-term research is needed to evaluate the efficacy of CDU versus CT, before CDU can be recommended as the primary imaging modality for EVAR surveillance, in place of CT for stable aneurysms.

Abdominal aortic aneurysm repair: long-term follow-up of endovascular versus open repair

INTRODUCTION

To compare early and long-term outcomes of endovascular abdominal aortic aneurysm repair (EVAR) versus open repair (OPEN).

DESIGN

Prospective observational, per protocol, non-randomized, with retrospective analyses.

MATERIAL AND METHODS

Between 2000 and 2005, a total of 311 patients having EVAR or OPEN repair of infrarenal abdominal aortic aneurysms were identified and included in this prospective single-center observational study. A propensity score-based optimal-matching algorithm was employed, and 138 patients undergoing EVAR procedures were matched (1: 1) to OPEN repair.

RESULTS

Open repair showed higher hospital mortality (17% vs. 6%, p = 0.004), respiratory failure (p < 0.026), transfusion requirement (p < 0.001), and intensive care unit admission (27% vs. 7%, p < 0.001), and longer hospitalization (p < 0.001). Median follow-up was 70 months (25(th) to 75(th) percentile, 24 to 101). Actuarial survival estimates at 1, 5 and 10 years were 93%, 74%, 49% for the OPEN group compared to 89%, 69%, 59% for the EVAR group (p = 0.465). A significant difference between groups was observed in younger patients (< 75 years) only (p < 0.044). Late complication and re-intervention rates were significantly higher in EVAR patients (p < 0.001 and p = 0.002, respectively). Freedom from late complications at 1, 5 and 10 years was 96%, 92%, 86%, and 84%, 70%, 64% for OPEN and EVAR procedures, respectively.

CONCLUSIONS

Our experience confirms the excellent results of the EVAR procedures, offering excellent early and long-term results in terms of safety and reduction of mortality. Patients < 75 years seem to benefit from EVAR not only in the immediate postoperative period but even in a long-term perspective.

The role of mandatory lifelong annual surveillance after thoracic endovascular repair

Thoracic endovascular aortic repair (TEVAR) has become an attractive and well-accepted option for the management of the various thoracic aortic pathologies that vascular surgeons are confronted with. As in the abdominal aorta, current management trends include the treatment of younger patients with longer life expectancies, raising the issue of postoperative surveillance. There are several relevant differences between these anatomic areas when it comes to surveillance, including the relative inaccessibility of the thoracic aorta to ultrasound interrogation and the increased variability of thoracic aortic pathologies and post-TEVAR complications. In addition, concerns regarding radiation-induced carcinogenesis and contrast-induced nephropathy reduce the enthusiasm of many surgeons for regular computed tomography surveillance. Most agree that surveillance is important after TEVAR, but the method, duration, and frequency of that surveillance is much less clear and is the topic of this debate.

Use of colour duplex ultrasound as a first line surveillance tool following EVAR is associated with a reduction in cost without compromising accuracy

INTRODUCTION

CT scanning remains the postoperative surveillance imaging modality of choice following EVAR. Concerns regarding cost, exposure to ionising radiation and intravenous contrast have led to a search for a less expensive, equally efficacious and safer method of monitoring EVAR patients after endograft deployment. This study evaluated the cost saving obtained if CDUS was employed as a first line surveillance tool following EVAR, as well as comparing the two entities in terms of efficacy.

PATIENTS & METHODS

Postoperative surveillance CTs and CDUS scans in the 145 patients who have undergone EVAR from 1st June 2003 to 1st July 2010 were compared for the detection of endoleak and determination of residual sac size.

RESULTS

Adopting a protocol where CDUS was employed as the first line surveillance tool following EVAR would result in a reduction in the number of postoperative CTs required in 2010 from 235 to 36. Based on 2010 costings, this would equate to an estimated reduction in expenditure from €117,500 to €34,915 a saving of €82,585. CDUS had a sensitivity of 100% and a specificity of 85% in the detection of endoleaks compared to CT. The positive predictive value was 28% and negative predictive value 100%. The Pearson Coefficient correlation of 0.96 indicates a large degree of correlation between CDUS and CT when measuring residual aneurysm size following EVAR.

CONCLUSION

CDUS can replace CT as the first line surveillance tool following EVAR. This is associated with a significant reduction in the cost of surveillance without any loss of imaging accuracy.

Two-dimensional versus three-dimensional CT angiography in analysis of anatomical suitability for stentgraft repair of abdominal aortic aneurysms

BACKGROUND

The morphological analysis prior to endovascular abdominal aneurysm repair (EVAR) plays an important role in long-term outcomes. Post-imaging analysis of computed tomographic angiography (CTA) by three-dimensional reconstruction with central lumen line detection (CLL 3D-CTA) enables measurements to be made in orthogonal slices. This might be more precise than equal post-imaging analysis in axial slices by two-dimensional computed tomographic angiography (2D-CTA).

PURPOSE

To evaluate the intra- and interobserver variability of CLL 3D-CTA and 2D-CTA post-imaging analysis methods and the agreement between them in pre-EVAR suitability analysis of patients with abdominal aortic aneurysm (AAA).

MATERIAL AND METHODS

Anonymized CTA data-sets from 70 patients with AAA were analyzed retrospectively. Length measurements included proximal and distal aortic neck lengths and total distance from the lower renal artery to the higher iliac bifurcation. Width measurements included proximal and distal neck diameters, maximum AAA diameter and common iliac diameters just above the iliac bifurcations. The measurements were performed in random order by two vascular surgeons, twice per method with 1-month interval between readings. In the CLL 3D-CTA method we used semi-automated CLL detection by software and manual measurements on CTA slices perpendicular to CLL. The equal measurements in 2D-CTA were performed manually on axial CTA slices using a DICOM viewer workstation. The intra- and interobserver variability, as well as the agreement between the two methods were assessed by Bland-Altman test and bivariate correlation analysis.

RESULTS

The intraobserver variability was significantly higher in 2D-CTA measurements for both readers. The interobserver variability was significant in 2D-CTA measurements of proximal neck dimensions while the agreement in CLL 3D-CTA analysis between the two readers was excellent in all studied parameters. The agreement between the two suitability analysis techniques was poor for both readers, especially in measurements of proximal neck's dimensions and in total aortoiliac length (p = 0.001).

CONCLUSION

In pre-EVAR morphological evaluation of AAAs the CLL-3D CTA post-imaging analysis has better intra- and interobserver correlation than 2D-CTA and might represent a useful tool for the proper selection of endograft's type and size.

Comparative analysis of hospital costs of open and endovascular thoracic aortic repair

BACKGROUND

Endovascular technologies represent major advancements in treating descending thoracic aortic aneurysms (DTAA). We compared hospital charges of open thoracic aortic replacement (OTAR) with endovascular repair of thoracic aortic aneurysms (TEVAR).

METHODS

Retrospective analysis of hospital charges related to repair of DTAA (2000-2009). Charges were inflation adjusted for dollars in 2009.

RESULTS

There were 50 OTAR and 50 TEVAR patients. Open thoracic aortic replacement charges were $64 531 (interquartile range [IQR]: 49 000-108 515) versus $61 909 (IQR: 41 307-92 109) for TEVAR(P = .4). A total of 10 patients (10%) died before discharge, with 0 TEVAR deaths (P < .05). For OTAR, supply charges ($9167) accounted for 13% of total charges versus 56% for TEVAR ($40 468), P < .01. Open thoracic aortic replacement length of stay (LOS) was 12 days (6 days intensive care unit [ICU] stay); bed charges comprised 40% of the total charges. Thoracic endovascular aneurysm repair had lower LOS (5days with 2 days ICU stay, P < .001).

CONCLUSIONS

Descending thoracic aortic aneurysm repair remains a formidable operation with significant resource utilization. Thoracic endovascular aneurysm repair does not significantly reduce overall hospital charges due to device costs but demonstrates improved mortality, ICU, and total LOS.

Is there a benefit of frequent CT follow-up after EVAR?

OBJECTIVE

Imaging follow-up (FU) after endovascular aneurysm repair (EVAR) is usually performed by periodic contrast-enhanced computed tomography (CT) scans. This study aims to evaluate the effectiveness of CT-FU after EVAR.

METHODS

In this study, 279 of 304 consecutive patients (261 male, aged 74 years (interquartile range (IQR): 70-79 years) with a median abdominal aortic aneurysm (AAA) diameter of 58 mm (IQR: 53-67 mm)) underwent at least one of the yearly CT scans and plain abdominal films after EVAR. All patients received Zenith stent-grafts for non-ruptured AAAs at a single institution. Patients were considered asymptomatic when a re-intervention was done solely due to an imaging FU finding. The data were prospectively entered in a computer database and retrospectively analysed.

RESULTS

As a follow-up, 1167 CT scans were performed at a median of 54 months (IQR: 34-74 months) after EVAR. Twenty-seven patients exhibited postoperative AAA expansion (a 5-year expansion-free rate of 88+/-2%), and 57 patients underwent 78 postoperative re-interventions with a 5-year secondary success rate of 91+/-2%. Of the 279 patients, 26 (9.3%) undergoing imaging FU benefitted from the yearly CT scans, since they had re-interventions based on asymptomatic imaging findings: AAA diameter expansion with or without endoleaks (n=18), kink in the stent-graft limbs (n=4), endoleak type III due to stent-graft limb separation without simultaneous AAA expansion (n=2), isolated common iliac artery expansion (n=1) and superior mesenteric artery malperfusion due to partial coverage by the stent-graft fabric (n=1).

CONCLUSIONS

Less than 10% of the patients benefit from the yearly CT-FU after EVAR. Only one re-intervention due to partial coverage of a branch by the stent-graft would have been delayed if routine FU had been based on simple diameter measurements and plain abdominal radiograph. This suggests that less-frequent CT is sufficient in the majority of patients, which may simplify the FU protocol, reduce radiation exposure and the total costs of EVAR. Contrast-enhanced CT scans continue, nevertheless, to be critical when re-interventions are planned.

Secondary Endovascular and Conversion Procedures for Failed Endovascular Abdominal Aortic Aneurysm Repair: Can We Still Be Optimistic?

The purpose of this study was to evaluate the incidence, etiology, and outcome of secondary endovascular and “open” conversion procedures after failed endovascular abdominal aortic aneurysm repair (EVAR). From January 1997 until December 2005, 625 patients with an infrarenal abdominal aortic aneurysm were treated by elective EVAR, with 98.7% ( n = 617) primary EVAR success. The mean follow-up of the 617 patients was 46.7 ± 11.2 months. One hundred of these patients (16.2%) required secondary endovascular or peripheral procedures, and 39 (6.3%) patients underwent a secondary abdominal conversion. There were 5 acute conversions (0.8%) and 34 elective conversions (5.5%). The pre-EVAR anatomic suitability data, the main cause of the secondary procedure, and stent graft type were compared between patients with primary EVAR success, patients in need of a secondary endovascular or peripheral procedure, and patients with abdominal conversion. The overall main causes for reinterventions were proximal migration ( n = 60; 9.7%), progressive kinking of the stent graft ( n = 59; 9.6%), and late type III endoleak ( n = 12; 1.9%). Multivariate logistic regression analysis showed that factors significantly correlated with secondary procedures were the abdominal aortic aneurysm's maximum diameter, the proximal neck's width and length, and particularly the commercial withdrawal of the stent graft ( p < .001). The morbidity and mortality rates of secondary endovascular or peripheral interventions were 0%. The mortality rate of acute secondary conversions was 20% ( n = 1) and of elective secondary conversions was 8.8% ( n = 3). The morbidity rates for acute and elective conversions were 0% and 65%, respectively. The aneurysm-related mortality rate in our series was below 1%. Abdominal conversion surgery still carries a high mortality rate, but the overall EVAR-related mortality rate remains low. Early pitfall detection and proper reintervention are crucial to long-term EVAR success.

The Durability of Evar — What are the Evidence and Implications on Follow-Up?

Background and Aims:

To investigate the durability of EVAR and to explore the evidence for follow-up investigations. Furthermore, to study the patients' impressions of follow-up investigations, and how complications and secondary procedures influence cost-effectiveness.

Material and Methods:

263 patients were treated by EVAR from february 1995-february 2007. The series is divided into two groups with the year 2000 as a cut-off point since a new generation of stent grafts was then introduced. Early and late complications and secondary procedures were recorded. A questionnaire study was performed to investigate the patients' views on the follow-up program.

Results:

There was a significant reduction of complications from period I to period II, which was also reflected in the reduction of secondary procedures. Freedom from secondary procedures were 47% and 93% at 5 years follow-up in the two periods, respectively. In phase II, 7.5% of the patients needed a secondary procedure. Limb extension and femoro-femoral bypass were the most common procedures. Since late complications still occur, and can be unpredictable, a follow-up program is necessary. The vast majority of the patients tolerated the follow-up program well.

Conclusions:

Although the number of complications following EVAR has decreased significantly over the years, a thorough follow-up program is still necessary. This follow-up regime is well tolerated by the patients. Reduction of secondary procedures is important to improve the cost-effectiveness of EVAR.