Systematic Review and Meta-analysis of Fenestrated and Chimney/Snorkel Techniques for Endovascular Repair of Juxtarenal Aortic Aneurysms.

Objectives: Comparative effectiveness of fenestrated endovascular aneurysm repair (FEVAR) and chimney graft endovascular aneurysm repair (ChEVAR) for juxtarenal aortic aneurysms (JAAs) remains unclear. Our objective was to identify and analyze the current body of evidence comparing the effectiveness of both techniques for JAA.

Methods: We performed a systematic review and meta-analysis comparing the effectiveness of FEVAR and ChEVAR for JAA repair. We searched MEDLINE, EMBASE, and Cochrane Register for Controlled Trials from January 1, 1990, for randomized and non-randomized studies assessing outcomes of FEVAR and ChEVAR for JAA repair. Screening, data extraction, risk of bias assessment, and GRADE (Grading of Recommendations, Assessments, Development, and Evaluations) certainty of evidence were performed in duplicate. Data were pooled statistically where possible.

Results: Nine retrospective cohort studies comparing the use of FEVAR and ChEVAR for juxtarenal aneurysm were included for meta-analysis. The FEVAR and ChEVAR arms of the meta-analysis consisted of 726 participants and 518 participants, respectively. There were 598 (86.8%) and 332 (81.6%) men in each arm. The mean diameter was larger in the ChEVAR arm (59 mm vs 52.5 mm). Both techniques had similar rates of postoperative 30-day mortality, 3.38% (8/237) versus 3.52% (8/227), acute kidney injury, 16.76% (31/185) versus 17.31% (18/104), and major adverse cardiac events, 7.30% (46/630) versus 6.60% (22/333). The meta-analysis supported the use of FEVAR for most outcomes, with significant advantage for technical success (odds ratio [OR]: 3.24, 95% CI: 1.24-8.42) and avoidance of type 1 endoleak (OR: 5.76, 95% CI: 1.94-17.08), but a disadvantage for spinal cord ischemia (OR: 10.21, 95% CI: 1.21-86.11), which had a very low number of events. The quality of evidence was "moderate" for most outcomes.

Conclusion: Both endovascular techniques had good safety profiles. The evidence does not support superiority of either FEVAR or ChEVAR for JAA.

Clinical Impact: While lack of equipoise has hampered the design of randomised trials of open versus endovascular repair of juxtarenal aortic aneurysms, concern about the durability of endovascular repair highlights the need for stronger evidence of the comparative efficacy of endovascular techniques. This review performed meta-analysis and evidence appraisal of recent data from large observational studies comparing fenestrated and chimney techniques, using a comprehensive outcome set. Superiority of either intervention could not be established due to differences in participants' baseline risk in each study arm. However, data suggests that both techniques are safe and suitable for use when indicated.