Bridging stent-graft fracture after branched endovascular aortic repair in a dual-center retrospective cohort study

Antithrombotic Therapy and Freedom From Bridging Stent Occlusion After Elective Branched Endovascular Repair: A Multicenter International Cohort Study

CLINICAL IMPACT

Based on our study, no antithrombotic therapy is significantly associated with bridging stent occlusion, and no evidence of the superiority of other antithrombotic therapy exists. Nevertehless, due to the low number of bridging stent occlusions, this study can neither support nor reject the PRINCE2SS recommendations. Further studies with larger cohorts are needed to determine clear guideliness of the best antithrombotic treatment regimen after complex enfovascular aortic repair.

Renovisceral artery alterations due to branched endovascular aortic repair and respiratory-induced deformations

OBJECTIVE

This study quantified respiratory-induced dynamics of branch vessels before and after thoracoabdominal aortic aneurysm (TAAA) branched endovascular aneurysm repair (bEVAR).

METHODS

Patients with TAAA were recruited prospectively and treated with bEVAR, predominantly with Zenith t-Branch and BeGraft Peripheral PLUS bridging stents. Using SimVascular software, three-dimensional geometric models of the vessels and implants were constructed from computed tomography angiograms during both inspiratory and expiratory breath-holds, preoperatively and postoperatively. From these models, branch take-off angles, end-stent angles (transition from distal end of stent to native artery), and curvatures were computed. Paired, two-tailed t tests were performed to compare inspiratory vs expiratory geometry and pre- vs postoperative deformations.

RESULTS

We evaluated 52 (12 celiac arteries [CA], 15 superior mesenteric arteries [SMA], and 25 renal arteries [RA]) branched renovisceral vessels with bridging stents in 15 patients. Implantation of bridging stents caused branch take-off angle to shift inferiorly in the SMA (P = .015) and RA (P = .014) and decreased the respiratory-induced branch angle motion in the CA and SMA by approximately 50%. End-stent angle increased from before to after bEVAR for the CA (P = .005), SMA (P = .020), and RA (P < .001); however, respiratory-induced deformation was unchanged. Bridging stents did not experience significant bending owing to respiration.

CONCLUSIONS

The decrease in respiratory-induced deformation of branch take-off angle from before to after bEVAR should decrease the risk of device disengagement and endoleak. The unchanging respiratory-induced end-stent bending, from before to after bEVAR, means that bEVAR maintains native vessel dynamics distal to the bridging stents. This factor minimizes the risk of tissue irritation owing to respiratory cycles, boding well for branch vessel patency. The longer bridging stent paths associated with bEVAR may enable smoother paths subject to less dynamic bending, and potentially lower fatigue risk, compared with fenestrated EVAR.

Analysis of predisposing factors for type III endoleaks from directional branches after branched endovascular repair for thoracoabdominal aortic aneurysms

BACKGROUND

Mid-term durability of branches has already been established, and BF-branched and fenestrated endovascular repair has shown comparable results with open repair in the treatment of thoracoabdominal aortic aneurysms (TAAAs). Nevertheless, target vessel instability remains the most frequent adverse event after complex endovascular aortic repair. Type III endoleaks from directional branches have been reported with a low incidence, but risk factors for this complication have not been investigated yet.

METHODS

This was a dual-center observational retrospective cohort study. Data were collected prospectively for each patient treated with branched endovascular repair between April 2008 and December 2019. The primary outcome was to assess potential risk factors for branch disconnection and fracture. A logistic regression analysis was performed, including preoperative and postoperative measurements as well as intraoperative details. A Cox regression hazard analysis was performed to evaluate the influence of preoperative aneurysm diameter and target vessel angulation on the outcome during follow-up.

RESULTS

Two hundred ninety-five target visceral vessels (TVVs) in 91 patients were considered suitable for cannulation. Technical success was 96.9% (286/295 TVVs). The median follow-up was 32.5 months (interquartile range, 14.2-50.1 months). Twelve type III endoleaks from directional branches were detected (4.2%; 5 bridging stent graft fractures and 7 disconnections). Five type III endoleaks involved the celiac trunk (one fracture and four disconnections), five the superior mesenteric artery (four fractures and one disconnection), and two the renal arteries (both disconnections). The median time to type III endoleak was 22.2 months (interquartile range, 10.9-37.6 months). Preoperative TAAA diameter (P = .028), preoperative TVV angulation (P = .037), the use of a BeGraft stent graft as bridging stent graft (P = .001), and different stent types on the same vessel (P = .048) were associated with type III endoleak at univariable analysis. Using a BeGraft stent graft (P = .010) was the only significant factor predisposing to type III endoleak at multiple logistic regression. The Cox regression analysis showed a two-fold increased risk for type III endoleak for every 10-mm increase in preoperative TAAA diameter (hazard ratio, 2.00; 95% confidence interval, 1.08-3.72; P = .028) and a 1.5 increased risk every 12° increase of preoperative TVV angulation (hazard ratio, 1.47; 95% confidence interval, 1.02-2.10; P = .037).

CONCLUSIONS

Type III endoleaks from directional branches are a non-negligible complication after branched endovascular repair, with a relevant incidence. They tended to be clustered on specific patients, and aneurysm diameter and TVV angulation are strictly associated with the outcome. Different stent types on the same vessel should be avoided whenever possible. An intensified follow-up should be adopted for patients with large aneurysms, implanted with first-generation BeGraft, or who have been already diagnosed with type III endoleaks.

Inner branched complex aortic repair outcomes from a national multicenter registry using the E-xtra design platform

BACKGROUND

Complex aortic pathology still represents an open issue in contemporary endovascular management, with continuous technological advancement being introduced in practice over time aiming to improve outcomes. Thus far, the dualism between the fenestrated and branched configuration for visceral artery revascularization is yet unsolved, with each approach having its own pros and cons. The inner branched technology for endovascular aneurysm repair (iBEVAR) aims to take the best out of both strategies, offering wide applicability and stable bridging stent sealing. The objective of this study was to evaluate the early outcomes obtained with a single manufacturer custom-made inner-branched endograft in a multicenter Italian experience.

METHODS

All patients consecutively treated with E-xtra design devices in three Italian facilities were enrolled. Anatomic characteristics and perioperative data were analyzed. The main objective was to asses technical and clinical success after iBEVAR. Secondary end points were overall survival, aortic-related mortality, target visceral vessel (TVV) patency, and freedom from target vessel instability during follow-up.

RESULTS

From 2016 to 2021, 45 patients were treated with an E-xtra design device revascularizing at least one visceral vessel through an inner branch. The mean age at the time of the procedure was 71.1 ± 9.3 years and 77.8% were males. The total number of target visceral arteries to be bridged with an inner branch was 159. The extent of aortic repair was thoracoabdominal in 91.1% of the cases. Technical success was achieved in 93.3% of the procedures (42/45) with all failures owing to a type I endoleak at final angiography. Each TVV was successfully connected to the graft's main body as planned without complications. Following their intervention, five patients developed spinal cord ischemia and in three of these cases symptoms persisted after discharge (6.7%). At 30 days clinical success was 93.3% (42/45). No death as well as no TVV thrombosis occurred within 30 days from the primary procedures. The mean follow-up was 22.8 ± 14.2 months. The Kaplan-Meier estimate of overall survival and TVV patency at 36 months were 83.9% and 95.9%, respectively.

CONCLUSIONS

Inner branches seem to be a promising technology in the complex aortic repair landscape, with an applicability ranging from type II thoracoabdominal aneurysm to type I endoleak repair after infrarenal endografting. Whether iBEVAR could offer results comparable with those provided by fenestrated/branched endovascular aneurysm repair in terms of target vessel patency and stent stability is yet to be established and further studies are, therefore, needed.