Final results from a postmarket registry of an iliac leg graft with a continuous, spiral nitinol stent

Incidence, Risk Factors, and Prognostic Impact of Type Ib Endoleak Following Endovascular Repair for Abdominal Aortic Aneurysm: Scoping Review

OBJECTIVE

The primary objectives of this scoping review were to assess the rate of and risk factors for type Ib endoleak and to evaluate the extent of the evidence base that links type Ib endoleak to short and long term outcomes in patients undergoing endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA).

METHODS

Potentially eligible studies were searched in the Cochrane Central Register of Controlled Trials, MEDLINE, Web of Science Core Collection, SciELO Citation Index, Russian Science Citation Index, and KCI-Korean Journal Database. A scoping review was performed according to PRISMA extension for Scoping Reviews.

RESULTS

A total of 27 articles (four prospective registries and 23 retrospective cohort studies) dealing with type Ib endoleak were included in the final analysis. The number of patients reported on was 7 197, with follow up ranging between 12 months and 93 months. The reported frequency of type Ib endoleak in patients treated with EVAR ranged from 0% to 8%, Patient and or procedure related factors associated with risk of type Ib endoleak were (1) common iliac artery (CIA) diameter ˃ 18 mm requiring use of flared stent graft limbs (FLs) ˃ 20 mm, (2) length of CIA landing zone ˂ 20 mm, (3) marked iliac tortuosity, and (4) large initial AAA diameter. Depending on the study, 50 - 100% of type Ib endoleaks were corrected by endovascular means, with a reported immediate technical success of 100% in the studies providing this information.

CONCLUSION

Type Ib endoleak after EVAR has been reported to occur in 0 - 8% of cases. Several anatomical features, including CIA diameter ˃ 18 mm or requiring the use of FLs ˃ 20 mm, length of CIA landing zone ˂ 20 mm, marked iliac tortuosity, and large initial AAA diameter, could increase the risk of type Ib endoleak and may require alternative therapeutic options and or more stringent follow up. Therefore, this updated scoping review provides a comprehensive summary of the frequency, risk factors, prognosis, and treatment of type Ib endoleaks, and has identified knowledge gaps in the literature to guide further studies.

Using the Evaluating Devices Using Claims and RegisTry Data (EDUCATe) Plan within the Vascular Implant Surveillance and Interventional Outcomes Network (VISION) to Analyze the Long-Term Outcomes following Endovascular Aortic Aneurysm Repair

BACKGROUND

Implanted devices undergo clinical trials to assess their safety and effectiveness. However, pivotal device trials are limited in their follow-up while postmarket surveillance may incompletely capture late failure. Linking clinical trials to Medicare claims can address these limitations. This study matched patients from investigational device exemption (IDE) clinical trials for endovascular aortic aneurysm repair (EVAR) to Medicare claims-based registry data to compare long-term device outcomes between the 2 sources.

METHODS

Patient-level data from 2 industry-sponsored IDE trials of EVAR devices was provided by a single industry partner. Trial data were matched at the patient level to data from the Vascular Implant Surveillance and Interventional Outcomes Network (VISION), a registry that is a part of the Society for Vascular Surgery Patient Safety Organization. The primary outcomes analyzed were survival and freedom from aneurysm-related reintervention.

RESULTS

Of 159 clinical trial patients, 134 were eligible for claims-based matching and 115 (85.5%) were successfully matched to VISION registry data. For the matched cohort, the Kaplan-Meier estimated survival was 94.8% at 1 year, 82.6% at 3 years, and 68.1% at 5 years. Estimates for freedom from reintervention were 90% at 1 year, 82.4% at 3 years, and 78.1% at 5 years. The estimates for survival were nearly identical between the clinical trial data and that found in the VISION data (log-rank P = 0.89). Freedom from reintervention was similar between the groups, with IDE trial reported freedom from reintervention of 87.3% and 73.3%, compared to VISION of 92.6% and 83% at 1 and 5 years, respectively (log-rank P = 0.13).

CONCLUSIONS

Clinical trial patients who undergo EVAR can be successfully matched to claims-based registry data to improve long-term device surveillance and outcomes reporting. Claims-based results agreed well with IDE trial results for patients through 5 years, supporting the accuracy of claims-based data for longer-term surveillance. Linking clinical trial and claims-based registry data can lead to robust device monitoring.

Long-term results of low-profile stent grafts for treatment of infrarenal aortic aneurysms: Results from a retrospective multicenter registry

OBJECTIVE

In recent years, manufacturers have developed new stent grafts with lower profiles to increase the endovascular aneurysm repair applicability. As reported by the current European Society for Vascular Surgery guidelines, long-term evaluation of such low-profile platforms is strongly recommended. This study aims to report outcomes beyond 5 years from a multicenter registry, including a real-world cohort of patients electively treated with low-profile stent grafts.

METHODS

A retrospective data collection of patients who had undergone elective implantation of low-profile endograft ≤16 Fr. (Zenith LP, Ovation, Incraft) was performed in nine centers. The primary endpoint was a long-term primary clinical success. Secondary endpoints were survival rate, freedom from abdominal aortic aneurysm (AAA)-related death, freedom from type I to III endoleak, limb patency, and freedom from all reinterventions. The Kaplan-Meier curves were stratified for investigative devices. A multivariate analysis evaluated predictors of primary clinical success and reintervention rate.

RESULTS

A total of 619 patients were enrolled (Ovation, n = 373; Incraft, n = 111; and Zenith LP, n = 135), with a mean follow-up of 56.8 ± 22.8 months. The overall primary and the secondary clinical success rate at 8 years was 72.1% and 93.8%, respectively. At 8 years, overall survival was 53.2%, freedom from AAA-related death was 94.4%, freedom from reintervention was 74%, freedom from type I/III endoleak was 86.9%, and limb patency was 90.4%. A significantly worse primary clinical success of the Zenith LP was recorded as dependent on more limb-related events. No differences between platforms were registered in the rate of AAA-related deaths, open conversion, sac enlargement, and type I/III endoleaks (P = .26). Multivariate analysis identified iliac tortuosity (hazard ratio, 2.053) and Zenith LP (hazard ratio, 3.818) as significant independent predictors of clinical failure and reintervention.

CONCLUSION

Low-profile stent grafts have acceptable long-term outcomes. Overall survival and AAA-related death were in line with those reported for traditional devices. Long-term surveillance and reintervention, when necessary, remain crucial to guarantee durability.

Limb Graft Occlusion Following Endovascular Aneurysm Repair for Infrarenal Abdominal Aortic Aneurysm with the Zenith Alpha, Excluder, and Endurant Devices: a Multicentre Cohort Study

OBJECTIVE

Limb graft occlusion (LGO) is a serious complication after endovascular aneurysm repair (EVAR) and while device development enables treatment of increasingly complex aortic anatomy, little is known about how endograft type affects the risk of occlusion. This observational study aimed to explore the incidence of LGO after EVAR for three major endograft systems.

METHODS

All patients with standard EVAR as the primary intervention for infrarenal abdominal aortic aneurysm (AAA), between January 2012 and December 2018, at five Swedish vascular surgery centres, were included in this multicentre retrospective cohort study. LGO was defined as a total limb occlusion regardless of symptoms, or a treated significant stenosis. A nested case control (NCC) design with incidence density sampling of 1:3 was used for analysis of potential per-operative and morphological risk factors. Conditional logistic regression was used to estimate multivariable odds ratios (OR) with 95% confidence intervals (CI) RESULTS: A total of 924 patients were included. The majority were male (84%), the mean age was 76 years (± 7.5 SD), and median AAA diameter was 59 mm (IQR 55, 67). Patients were treated with Zenith Alpha (n = 315, ZISL limbs), Excluder (n = 152, PLC/PXC limbs), and Endurant (n = 457, ETLW/ ETEW limbs). During median follow up of 37 months (IQR 21, 62), 55 occlusions occurred (5.9%); 39 with Zenith Alpha (12.4%), one with Excluder (0.7%), and 15 with Endurant (3.3%). In the NCC analysis, the Zenith Alpha device (OR 5.31, 95% CI 1.97 - 14.3), external iliac artery (EIA) landing (OR 5.91, 95% CI 1.30 - 26.7), and EIA diameter < 10 mm (OR 4.99, 95% CI 1.46 - 16.9) were associated with an increased risk of LGO.

CONCLUSION

Endograft device type is an independent risk factor for LGO after EVAR. Specifically, the Zenith Alpha demonstrated an increased risk of LGO compared with the Endurant and Excluder devices. In addition, a narrow EIA and landing zone in EIA are also risk factors for LGO.