Mid-term results on a new self-expandable covered stent combined with branched stent-grafts: insights from a multicenter Italian registry

Objective: To investigate the technical periprocedural and mid-term outcomes of endovascular repairs with multibranched (BEVAR) or iliac-branch devices (IBD) combined with a new self-expanding covered stent. Methods: The COBRA (COvera in BRAnch) registry is a physician-initiated, multicenter, ambispective, observational registry (ClinicalTrials.gov Identifier: NCT04598802) enrolling patients receiving a BEVAR or IBD procedure mated with Bard Covera Plus (Tempe, Arizona, USA) covered stent, designed to evaluate the outcomes of the covered stent mated with patient-specific and off-the-shelf branched stent-graft. Primary endpoints were technical success, branch instability, and freedom from aortic and branch-related reintervention within 30 days and at follow-up. Preoperative characteristics, comorbidities, and outcomes definition were graded according to the Society for Vascular Surgery reporting standards. Results: Two hundred eighty-four patients [76 years (70-80); 79% males] in 24 centers were enrolled for a total of 708 target vessels treated. The CSs were mated with an off-the-shelf graft in 556 vessels (79%) and a custom-made graft in 152 (21%). Three-hundred-seven adjunctive relining stents in 277 vessels (39%) were deployed, of which 116 (38%) proximal, 66 (21%) intrastent and 125 (41%) distal. Adjunctive relining stent placement was more frequent when landing in a vessel branch instead of the main trunk (59%vs39%, p=.031), performing a percutaneous access (49%vs35%, p<.001), using a stent with a diameter ≥8mm (44%vs36%, p=.032) and a length ≥80mm (65%vs55%, p=.005), when a post-dilatation was not performed (45%vs29%, p<.001) and when an inner-branch configuration was used (55%vs35%, p<.001). Perioperative technical bridging success was 98%. Eight patients (3%) died in the perioperative period. Two deaths (1%) were associated with renal branch occlusion followed by acute kidney injury and paraplegia. Follow-up data were available for 638 vessels (90%) at a median of 32 months (Q1, Q3: 21,46). A branch instability was reported in 1% of branches. Forty-six (17%) patients died during follow-up, nine (3%) of them due to aortic-related causes. Primary patency rates at one year, two and three years were 99% (581/587), 99% (404/411), and 97% (272/279) respectively. Branch instability was associated with patient-specific devices (9% vs 4%, p=.014) and intrastent adjunctive stent placement (12% vs 2%, p=.003), especially when a bare metal balloon-expandable stent was used (25%vs3%, p<.001). Conclusions: The use of this new self-expanding covered stent mated with branched endografts proved to be safe and feasible with high technical procedural success rates. Low rates of branch instability were observed at mid-term follow-up. Comparative studies with other commercially available covered stents are warranted.