Durability of abdominal aortic endograft with the Talent Unidoc stent graft in common practice: Core lab reanalysis from the TAURIS multicenter study

A comparison of treating physician versus independent core lab assessments of post-aneurysm treatment imaging outcomes: an analysis of prospectively collected data from a randomized trial

OBJECTIVE

Aneurysm occlusion has been used as surrogate marker of aneurysm treatment efficacy. Aneurysm occlusion scales are used to evaluate the outcome of endovascular aneurysm treatment and to monitor recurrence. These scales, however, require subjective interpretation of imaging data, which can reduce the utility and reliability of these scales and the validity of clinical studies regarding aneurysm occlusion rates. Use of a core lab with independent blinded reviewers has been implemented to enhance the validity of occlusion rate assessments in clinical trials. The degree of agreement between core labs and treating physicians has not been well studied with prospectively collected data.

METHODS

In this study, the authors analyzed data from the Hydrogel Endovascular Aneurysm Treatment (HEAT) trial to assess the interrater agreement between the treating physician and the blinded core lab. The HEAT trial included 600 patients across 46 sites with intracranial aneurysms treated with coiling. The treating site and the core lab independently reviewed immediate postoperative and follow-up imaging (3-12 and 18-24 months, respectively) using the Raymond-Roy occlusion classification (RROC) scale, Meyer scale, and recanalization survey. A post hoc analysis was performed to calculate interrater reliability using Cohen's kappa. Further analysis was performed to assess whether degree of agreement varied on the basis of various factors, including scale used, timing of imaging, size of the aneurysm, imaging modality, location of the aneurysm, dome-to-neck ratio, and rupture status.

RESULTS

Minimal interrater agreement was noted between the core lab reviewers and the treating physicians for assessing aneurysm occlusion using the RROC grading scale (k = 0.39, 95% CI 0.38-0.40) and Meyer scale (k = 0.23, 95% CI 0.14-0.38). The degree of agreement between groups was slightly better but still weak for assessing recanalization (k = 0.45, 95% CI 0.38-0.52). Factors that significantly improved degree of agreement were scales with fewer variables, greater time to follow-up, imaging modality (digital subtraction angiography), and wide-neck aneurysms.

CONCLUSIONS

Assessment of aneurysm treatment outcome with commonly used aneurysm occlusion scales suffers from risk of poor interrater agreement. This supports the use of independent core labs for validation of outcome data to minimize reporting bias. Use of outcome tools with fewer point categories is likely to provide better interrater reliability. Therefore, the outcome assessment tools are ideal for clinical outcome assessment provided that they are sensitive enough to detect a clinically significant change.

A Systematic Review of the Recruitment and Outcome Reporting by Sex and Race/Ethnicity in Stent Device Development Trials for Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

Women and racial/ethnic minority groups have been shown to experience poor outcomes after endovascular aortic aneurysm repair (EVAR). One potential reason is the rare inclusion of these populations in initial phases of device development. The objective of this systematic review is to understand enrollment and outcome reporting by sex and race/ethnicity in industry-funded EVAR device development trials.

METHODS

MEDLINE, PubMed, and Embase were searched from inception to January 2022 without language restrictions using the following terminology: "stent", "graft", "endograft", "device", and "abdominal aortic aneurysm" (AAA).

CLINICALTRIALS

gov was also searched from inception to January 2022 for "AAA." Two independent reviewers screened and extracted data. All phase I-III and postmarket evaluation trials that included patients ≥18 years of age, who underwent EVAR were assessed. Participation-to-prevalence ratios (PPRs) were calculated to estimate representation of participants by sex and race/ethnicity in trials compared with their share of disease burden.

RESULTS

Among the 4,780 retrieved articles, 55 industry-funded trials met inclusion criteria for this review. A total of 51 trials (93%) reported enrollment by sex/gender, and only 7 trials (13%) reported enrollment by race/ethnicity of the participants. A median of 19 (interquartile range [IQR]: 4.5, 51) women participants were recruited compared to 171 (IQR: 57, 311.5) men, and 17 (IQR: 7.5, 21.5) racial/minority patients were recruited compared to 241 (IQR: 123, 463.5) White participants. Women represent 16.6% of the disease population, and the median PPR is 0.62 (IQR: 0.42, 0.88), which has remained constant over time (Figure 1). None of the device trials reported outcomes based on sex/gender or race/ethnicity.

CONCLUSIONS

This systematic review highlights the disparities in recruitment and outcome reporting based on sex and race/ethnicity in EVAR device development trials. While most trials may be underpowered to study these differences, recent registry studies show differential outcomes based on sex and race/ethnicity of vascular patients. Therefore, it is imperative to include and report outcomes in these participants, starting from the initial device development phases to improve generalizability of device-use and understand sources of variation in device performance.

Parallel Placement of Excluder Legs for the Treatment of a Type IIIb Endoleak Using AFX2

Endoleak is a major complication of endovascular aneurysm repair (EVAR). Type IIIb endoleaks, which are caused by endograft fabric disruption, are relatively rare. Although relining of the previously placed endograft with another main endograft is considered an ideal approach, it is sometimes difficult. The efficacy of parallel placement of Excluder legs has been reported in various settings. Here, we report the successful treatment of a type IIIb endoleak with parallel placement of Excluder legs during EVAR by using an AFX2 device.

Clinical and anatomical variables associated in the literature to limb graft occlusion after endovascular aneurysm repair compared to the experience of a tertiary referral center

INTRODUCTION

Limb graft occlusion (LGO) is the third reason for hospital readmission after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm. We reviewed the clinical features, incidence, anatomical and devices related predictive factors for LGO after EVAR, and compared them with our experience.

EVIDENCE ACQUISITION

EVAR between 2010-2017 were included. Patients with LGO (LGO group) were matched for age and type of endograft with the rest of the entire cohort without LGO (control group). Clinical, anatomical, operative, outcome, and follow-up data were collected.

EVIDENCE SYNTHESIS

Two hundred seventy-six EVAR, (30 aorto-uniliac), 276 patients. The incidence of LGO was 2.5% (seven limbs, seven patients) at 27±24.6 days. Symptomatic patients were successfully treated. No mortality, limb loss, critical limb ischemia or residual claudication due to LGO was observed. Fifty patients resulted from the matching. Among the predictive factors of LGO between the two groups, significant differences were observed in graft limb oversizing ≥15% (57.1% vs. 8%, P=0.005), or kinking (42.9% vs. 2%, P=0.01), and diameter of the aortic bifurcation <20 mm (71.4% vs. 20%, P=0.01). Logistic regression analysis showed that these three variables increased the risk of LGO (P=0.003, P=0.006, and P=0.01, respectively).

CONCLUSIONS

The strongest predictive factors of LGO issued from our review were: extension in the external iliac artery, or small diameter; tortuous, angled, and calcific iliac axis; excessive oversizing of the limb graft, or kinking; use of old generation devices; EVAR performed outside the instructions for use. Limb graft oversizing >15%, or kinking, and aortic bifurcation <20 mm appear to be independent predictive factors of LGO.

Parallel placement of Excluder legs for treatment of type IIIb endoleaks caused by fabric tear after endovascular aneurysm repair

A total of 576 patients underwent endovascular aneurysm repair using main body devices for treatment of abdominal aortic aneurysms or iliac artery aneurysms. During follow-up, type IIIb endoleaks caused by fabric tear occurred in six patients (1.0% [6/576]). The device used was Zenith (Cook Medical, Bloomington, Ind) in five cases and Talent (Medtronic, Santa Rosa, Calif) in one case. All endoleaks were close to the flow divider of the main body devices. The distance between the lower renal artery and the top end of the contralateral leg was 53 ± 14 mm. Bell-bottom-shaped Excluder (W. L. Gore & Associates, Flagstaff, Ariz) legs were placed parallel from the top of the main body device through both legs to treat these endoleaks. In two patients, coil embolization was required to treat gutter endoleaks. Postoperative computed tomography showed the obliteration of type IIIb endoleaks in all patients. Our technique may be an acceptable method for treatment of type IIIb endoleaks, especially when they occur near the flow divider.

Stent graft surface movement after infrarenal abdominal aortic aneurysm repair: comparison of patients with and without a type 2 endoleak

OBJECTIVES

The aim was to compare multidirectional stent graft movement in patients with and without a type 2 endoleak.

METHODS

This was a retrospective case control study of patients being followed up after elective endovascular aneurysm repair of abdominal aortic aneurysms. The post-procedural and final follow up multislice computed tomography (MSCT) of 69 patients with and 74 without a type 2 endoleak were analyzed. Three dimensional (3D) surface models of the stent graft, delimited by landmarks using custom built software, were derived from these MSCT data. The stent graft was segmented in different zones, and the proportion of the total stent graft surface moving >9 mm between the post-procedural and the final follow up MSCT was calculated, given in percentages, and compared between groups. Changes of infrarenal neck, renal artery to stent graft distance, and freedom from stent graft related endoleaks were evaluated.

RESULTS

Overall surface movement was higher in the no endoleak (18.8%, IQR 0.1-45.1%) than in the type 2 endoleak group (5.3%, IQR 0-29.7%; p = .06). Furthermore, significantly higher surface movement in the no endoleak group was found in the proximal anchoring zone (p = .04) and the distal left limb (p = .01), which was the modular limb in 81.1% (p < .01). Neck diameter increase (1.0 mm, IQR 0-3.0 mm; p < .01) and renal artery to stent graft distance difference (0 mm, IQR 0-3.3 mm; p < .01) were significantly higher in the no endoleak group. Five patients in the no endoleak and one patient in the type 2 endoleak group suffered from a stent graft related endoleak (p = .27).

CONCLUSIONS

The presence of a type 2 endoleak is associated with decreased surface movement of the proximal anchoring zone and the distal modular limb of bifurcated stent grafts.

Type II endoleaks after endovascular repair of abdominal aortic aneurysms: fate of the aneurysm sac and neck changes during long-term follow-up

PURPOSE

To evaluate the frequency of type II endoleaks after endovascular aneurysm repair (EVAR) and to compare sac diameter and neck changes in patients with type II endoleak to endoleak-free patients with at least 3-year imaging follow-up.

METHODS

Among 407 consecutive EVAR patients, 109 patients (101 men; mean age 72.1 years, range 55-86) had at least 3-year computed tomography (CT) data and no type I or III endoleak. In this cohort, 49 patients presented with a type II endoleak at some time and 60 patients had no endoleak. Patients with type II endoleaks were further divided into subgroups based on the vessel origin and the perfusion status (persistent or transient). The course of the perfusion status of type II endoleaks and changes in the aneurysm sac diameters, neck diameters, and renal to stent-graft distances (RSD) were evaluated in the defined groups. Reintervention and death rates were also reported.

RESULTS

The mean follow-up was 68.1 ± 23.8 months. Compared to the no endoleak group, overall sac diameter increased significantly in the type II endoleak group (p = 0.007), but vessel origin did not have any influence. With regard to the perfusion status of type II endoleaks, aneurysm sac changes were significantly higher (p = 0.002) in the persistent endoleak group. During the study period, the increase in the proximal neck diameter was significantly higher in the no endoleak group compared to the type II endoleak group (p = 0.025). No significant difference was found in RSD changes between the defined groups. Reinterventions were performed in 20 (18.3%) patients (13 for type II endoleak); 2 (1.8%) patients without type II endoleak died of ruptured aneurysm.

CONCLUSION

Persistent type II endoleaks led to significant aneurysm sac enlargement, but without increased mortality or rupture rates.

Quality improvement guidelines for imaging detection and treatment of endoleaks following endovascular aneurysm repair (EVAR)

Major concerns after aortic aneurysm repair are caused by the presence of endoleaks, which are defined as persistent perigraft flow within the aortic aneurysm sac. Diagnosis of endoleaks can be performed with various imaging modalities, and indications for treatment are based on further subclassifications. Early detection and correct classification of endoleaks are crucial for planning patient management. The vast majority of endoleaks can be treated successfully by interventional means. Guidelines for Imaging Detection and Treatment of endoleaks are described in this article.

Long-term dilatation of polyester and expanded polytetrafluoroethylene tube grafts after open repair of infrarenal abdominal aortic aneurysms

OBJECTIVES

Since 1995, expanded polytetrafluoroethylene (ePTFE) grafts have been implemented in open surgical repair (OSR) of abdominal aortic aneurysms (AAA) and are supposed to show less dilatation than polyester grafts. This study examined differences in graft dilatation and clinical outcome.

METHODS

This single-center long-term, prospective randomized study monitored 99 consecutive patients after OSR of AAA. Implanted were 90 tube ePTFE Gore-Tex Stretch grafts, 56 tube Dacron grafts (Uni-Graft KDV, polyester, B. Braun, knitted), and 51 tube Dacron grafts (Gelseal Plus, polyester, Vascutek, triaxial knitted). Follow-up with ultrasound examination was performed at discharge, at 12 months, and at 6 years.

RESULTS

Patients were a mean age of 67 years. Thirty-day mortality was 2.5% (n = 5 of 199), without significant differences among the groups. The Kaplan-Meier analysis showed 5-year survivals of 0.82 (ePTFE/Gore), 0.81 (polyester/Braun), and 0.83 (polyester/Vascutek). Mean ± standard deviation dilatation of the midgraft segment was 1% ± 5% (ePTFE/Gore), 10% ± 9% (polyester/Braun), and 7% ± 8% (polyester/Vascutek) (P ≤ .001) at discharge; 8% ± 11% (ePTFE/Gore), 24% ± 7% (polyester/Braun), and 20% ± 13% (polyester/Vascutek; P ≤ .001) after 12 months; and 19% ± 21% (ePTFE/Gore), 33% ± 22% (polyester/Braun), and 23% ± 19% (polyester/Vascutek; (P ≤ .001) after 6 years. No graft failure or rupture occurred. Graft patency was 100%.

CONCLUSIONS

After a mean implantation of 6 years, the ePTFE/Gore, polyester/Braun, and polyester/Vascutek tube grafts presented with significant differences. The ePTFE grafts showed a stronger resistance against dilatation than the two types of polyester grafts. Owing to similar perioperative and postoperative courses, no advantage could be identified in any group concerning the overall outcome. Vascular implants for OSR of AAA made of ePTFE and polyester are safe, even after a long implantation time. Therefore, the choice of the suitable graft does not depend on its postimplantation dilative characteristics. The outcome is not likely to be connected with dilatation of the implanted graft, because a causal connection between graft dilatation and death cannot be made. The study does not offer a basis for the preference of one of the three graft types. Nevertheless, continuous ultrasound examinations should be performed after implantation of an aortic tube graft to identify possible problems arising from changes in the graft and the residual vascular branches over time.

Five-year results for the Talent enhanced Low Profile System abdominal stent graft pivotal trial including early and long-term safety and efficacy

OBJECTIVES

The pivotal trial of the Talent enhanced Low Profile System (eLPS; Medtronic Vascular, Santa Rosa, Calif) stent graft evaluated short and long-term safety and efficacy of endovascular aneurysm repair (EVAR). These data and a confirmatory group assessing the performance of the CoilTrac delivery system supported the United States premarket approval application for the device.

METHODS

The pivotal trial was a prospective, nonrandomized study conducted at 13 sites from February 2002 to April 2003. The study group (n = 166) underwent EVAR using the Talent eLPS stent graft. The control group (n = 243) underwent open surgical AAA repair. Data for this group were obtained from the Society for Vascular Surgery Endovascular AAA Surgical Controls project. Outcomes were compared at 30 days and 12 months. Additional 5-year follow-up was obtained for the eLPS group. A single-center cohort of 137 patients was the confirmatory group for the assessment of the clinical performance of the CoilTrac delivery system, with analysis of outcomes <or=30 days from the procedure.

RESULTS

AAA anatomy with neck length as short as 3 mm and maximum neck diameter of 32 mm were included in the eLPS group. EVAR was superior to open repair for periprocedural outcomes, including mean procedure duration (167.3 vs 196.4 minutes, P < .001), blood transfusion (18.2% vs 56.8%, P < .001), median intensive care unit stay (19.3 vs 74.3 hours, P < .001), and mean hospital stay (3.6 vs 8.2 days, P < .001). Freedom from major adverse events was 89.2% for EVAR at 30 days vs 44.0% (P < .001) and 81.3% vs 42.4% at 1 year (P < .001). Freedom from all-cause mortality and aneurysm-related mortality (ARM) was 93.7% and 98.2% for EVAR vs 92.4% and 96.7% for the controls. Through 5 years for the EVAR group, rates of freedom from all-cause mortality, ARM, aneurysm rupture, and conversion to surgery were 69.8%, 96.5%, 98.2%, and 99.1%, respectively, with one conversion to surgery, 25 secondary reinterventions, and five site-reported instances of stent graft migration. The technical success rate for the CoilTrac confirmatory group was 100%, with no aneurysm rupture or conversion to open repair at 30 days. The 30-day all-cause mortality rate was 1.5% (2 of 137).

CONCLUSIONS

In a population with challenging anatomic characteristics, EVAR with the Talent eLPS and use of the CoilTrac delivery system compared favorably with open repair through 1 year. Sustained protection from ARM, with minimal reinterventions, was attained through 5 years.