Meta-analysis of Comparative Studies Between Self- and Balloon-Expandable Bridging Stent Grafts in Branched Endovascular Aneurysm Repair

Target Vessel-Related Outcomes in Patients Managed With Branch Thoracic Aortic Endovascular Repair

INTRODUCTION

Data on target vessel (TV)-related outcomes in patients managed with branched thoracic endovascular aortic repair (BTEVAR) are limited. This study aimed to present the TV-related outcomes of BTEVAR in patients managed for aortic arch pathologies at 30 days and during follow-up.

METHODS

A retrospective analysis of consecutive patients, managed between September 1, 2011, and June 30, 2022, with custom-made aortic arch endografts (Cook Medical, Bloomington, IN, USA), presenting at least one branch configuration, were eligible. Primary outcomes were technical success, TV-related patency, and reinterventions at 30 days.

RESULTS

In total, 255 TVs were revascularized using branches: 107 innominate arteries (IAs), 108 left common carotid arteries (LCCAs), and 40 left subclavian arteries (LSAs). Covered stents were used as bridging stents of which 10.2% were balloon expandable. Relining, using bare-metal stents (BMS), was performed in 14.0% of IAs, 35.2% of LCCAs, and 22.5% of LSAs. Technical success on case basis was 99.2%; no failure was related to unsuccessful TV bridging. At 30 day follow-up, no TV occlusion was detected. In 5.6% of cases, a type Ic or III endoleak, attributed to TVs, was recorded. Two patients needed early branch-related reintervention. The mean follow-up was 18.3±9.2 months. Freedom from TV instability was 94.6% (standard error [SE] 2.5%] at 12 months. No TV stenosis or occlusion was detected up to 48 months of follow-up. Freedom from TV-related reinterventions was 95.4% [SE 2.4%] at 12 months.

CONCLUSION

TV stenosis or occlusion in BTEVAR cases is rare and TV-related reinterventions and instability events are mainly attributed to type Ic and III endoleak formation.

CLINICAL IMPACT

Previous studies focusing on target vessel (TV) outcomes after endovascular aortic arch repair are limited. In this study, including 255 TVs revascularized using branched arch devices, bridging was performed with covered stents, of which 90% were self-expanding. Relining was at the discretion of the operator and was 14% for the innominate, 35.2% for the left common carotid and 22.5% for the left subclavian artery branches. No 30-day occlusion was detected. The freedom from TV instability was almost 95% at 12 months. TV instability and reintervention were mainly attributed to endoleaks type Ic and IIIc.

Early Outcomes on Triple-Branch Arch Device With Retrograde Left Common Carotid Branch: A Case Series

INTRODUCTION

Endovascular aortic arch repair using multibranch devices has been applied in patients considered at high risk for open repair. The aim of this case series was to report the early outcomes in patients managed with a new design 3 branch arch custom-made device, including a retrograde left common carotid artery (LCCA) branch.

METHODS

The Preferred Reporting Of CaSe Series in Surgery (PROCESS) guidelines were followed. All consecutive patients undergoing endovascular repair of an aortic arch lesion with a custom-made triple-branch device, including a retrograde LCCA branch (Cook Medical, Bloomington, IN, USA), between October 27, 2022, and February 28, 2023, were included. The presence of an arch aneurysm (degenerative or post-dissection) with diameter ≥55 mm and high risk for a conventional open repair set the indication for treatment. The primary outcomes were technical success and mortality at 30 days. Early morbidity and reinterventions were considered as secondary outcomes.

RESULTS

Eight elective patients (87.5% men, mean age 72.3±27.0 years) were included. Five of them (62.5%) had undergone a previous ascending aorta repair of an acute type A aortic dissection. All patients were asymptomatic, except one, with left recurrent laryngeal nerve compression. The mean maximum aortic diameter was 70.4±21.0 mm. Percutaneous femoral and axillary access was used in all cases except three in which a cut down for right carotid access was performed. Technical success was 100%. Femoral access to the LCCA and implantation of the bridging stent was performed without technical challenges. No death nor cerebrovascular event was recorded during the 30 day follow-up. Five patients (62.5%) presented major complications, 3 related to access needing reintervention and the remaining related to congestive heart failure (CHF), which were managed successfully with medical treatment. Follow-up (range 1-4 month) was uneventful, except for one patient who presented a secondary type Ia endoleak.

CONCLUSIONS

According to our early experience, the presence of a retrograde branch facilitated the revascularization of the LCCA through femoral access, decreasing the risk of cerebrovascular morbidity. Further analyses with longer follow-up are needed to evaluate the safety and efficacy of the device.

CLINICAL IMPACT

Data arising mainly from the retrograde branch for the revascularization of the LSA are encouraging from a variety of devices. The premiminary experience with a triple-branched arch device, with a retrograde branche for the LSA but also for the LCCA, was associated with no 30 day mortality and 100% technical success.The device's design allowed swift catheterization and completion of the LCCA revascularization using femoral access exclusively.

Two-year target vessel-related outcomes following use of off-the-shelf branched endografts for the treatment of thoracoabdominal aortic aneurysms

OBJECTIVE

The aim of this study was to assess clinical outcomes and target vessel patency through 2 years following thoracoabdominal aortic aneurysms (TAAA) repair with the off-the-shelf Zenith t-Branch Thoracoabdominal Endovascular Graft (William Cook Europe).

METHODS

This post-market observational study was conducted at three European sites with ambispective enrollment from 2012 to 2017. Patients underwent endovascular TAAA repair with the t-Branch graft and bridging stent grafts (BSGs) for the celiac (CA), superior mesenteric (SMA), left renal (LRA), and/or right renal (RRA) arteries. Follow-up was through 2 years, per sites' standard of care. Procedural and 1-year results were reported previously.

RESULTS

Eighty patients (mean age, 71.0±7.4 years; 70.0% men) were enrolled; six patients had symptomatic TAAAs, and 15 patients had contained ruptures. Technical success was achieved in 98.8% of patients (79/80). Median follow-up was 22.2 months (interquartile range, 9.2-25.1 months). At 24 months, Kaplan-Meier (KM) freedom from all-cause and aneurysm-related mortality were 78.5% and 98.6%, respectively. Beyond 12 months, 38 adverse events occurred in 20 patients, including two aortic ruptures (one study aneurysm and one non-study aneurysm) and six deaths (none aneurysm-related, as reported by the site). Compared with postprocedure, maximum aneurysm diameter decreased (>5 mm) in 84.6% (44/52), remained unchanged in 3.8% (2/52), and increased (>5 mm) in 11.5% (6/52) of patients with imaging follow-up after 12 months. No conversions to open repair, and no t-Branch graft or other endograft component migration or integrity issues were reported. No loss of patency was reported in the t-Branch or iliac limb grafts throughout the study. Throughout study duration, four patients had five imaging-reported BSG compressions, none of which required secondary intervention. KM freedom from secondary intervention was 76.3% at 24 months. Fourteen target vessel-related secondary interventions were performed, primarily consisting of stent placement for endoleak, stenosis, or occlusion. KM freedom from loss of primary patency was 94.8%, 100%, 91.3%, and 89.3% for the CA, SMA, LRA, and RRA, respectively, at 24 months. KM freedom from loss of secondary patency in the CA, SMA, LRA, and RRA were 96.3%, 100%, 98.2%, and 98.3% at 24 months, respectively. A total of 298 vessels were targeted, of which 12 were occluded over the study period.

CONCLUSIONS

Primary and secondary target vessel patency rates through 2 years demonstrated durable repair with the t-Branch graft in patients treated for symptomatic or asymptomatic thoracoabdominal aortic aneurysms.

Effect of bridging stent graft selection for directional branches on target artery outcomes of fenestrated-branched endovascular aortic repair in the United States Aortic Research Consortium

OBJECTIVE

The purpose of this study was to evaluate the effect of directional branches (DBs) bridging stent choice on target artery (TA) outcomes during fenestrated-branched endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms.

METHODS

Patients enrolled in nine prospective physician-sponsored investigational device exemption studies in the United States between 2005 and 2020 were analyzed. All patients who had at least one TA incorporated by DB using either self-expandable (SESGs), balloon-expandable (BESGs), or hybrid stent graft combinations (HSGs). Endpoints were TA patency and freedom from TA endoleak, instability, and reintervention.

RESULTS

There were 800 patients with 2426 renal-mesenteric arteries incorporated by DBs. DB stent selection was SESGs in 1205 TAs (50%), BESGs in 1095 TAs (45%), and HSGs in 126 TAs (5%). SESGs were predominantly used in the first three quartiles of the study period, whereas BESGs comprised 75% of all stents between 2017 and 2020. The median follow-up was 15 months (interquartile range, 6-35 months). At 5 years, BESGs had significantly lower freedom from TA instability (78% ± 4% vs 88% ± 1% vs 96% ± 2%; log-rank P =.010), freedom from TA endoleaks (87% ± 3% vs 97% ± 1% vs 99% ± 1%; log-rank P < .001), and freedom from TA reintervention (83% ± 4% vs 95% ± 1% vs 99% ± 2%; log-rank P <.001) compared with SESGs or HSGs, respectively. For renal arteries, there was no difference in freedom from TA instability for BESGs, SESGs, or HSGs. However, freedom from TA endoleaks and reintervention were lower for renal arteries targeted by BESGs compared with DBs targeted by SESGs and HSGs (83% ± 6% vs 98% ± 1% vs 100%; log-rank P < .001; and 70% ± 10% vs 92% ± 1% vs 96% ± 4%; log-rank P = .022). For mesenteric arteries, DBs targeted by BESGs had lower freedom from TA instability, endoleak, and reintervention than SESGs or HSGs. In stent-specific analysis, iCAST BESGs had the lowest freedom from TA instability either for renal or mesenteric arteries, primarily due to higher rates of TA endoleaks. There was no difference in patency in any scenario. Independent predictors of TA instability were age (+1-year: hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.94-0.99), stent diameter (+1 mm: HR, 0.67; 95% CI, 0.57-0.80), and BESG (HR, 1.8; 95% CI, 1.1-2.9).

CONCLUSIONS

DBs incorporated using BESGs had lower freedom from TA instability, TA endoleak, and TA reintervention compared with SESGs and HSGs. The patency of DBs was not affected by the type of stent construction. The observed performance disadvantage associated with BESGs appears to have largely been driven by iCAST usage.

Midterm 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 midterm outcomes of endovascular repairs with multibranched endovascular repair or iliac branch devices combined with a new self-expanding covered stent.

METHODS

The COvera in BRAnch registry is a physician-initiated, multicenter, ambispective, observational registry (ClinicalTrials.gov Identifier: NCT04598802) enrolling patients receiving a multibranched endovascular repair or iliac branch devices procedure mated with Bard Covera Plus (Tempe, AZ) covered stent, designed to evaluate the outcomes of the covered stent mated with patient-specific and off-the-shelf branched stent graft. Primary end points 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 definitions were graded according to the Society for Vascular Surgery reporting standards.

RESULTS

Two hundred eighty-four patients (76 years; range, 70-80 years; 79% males) in 24 centers were enrolled for a total of 708 target vessels treated. The covered stents 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%) were 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% vs 39%; P = .031), performing a percutaneous access (49% vs 35%; P < .001), using a stent with a diameter of 8 mm or greater (44% vs 36%; P = .032) and a length of 80 mm or greater (65% vs 55%; P = .005), when a post-dilatation was not performed (45% vs 29%; P < .001) and when an inner branch configuration was used (55% vs 35%; 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). Branch instability was reported in 1% of branches. Forty-six patients (17%) died during follow-up, nine (3%) of them owing to aortic-related causes. Primary patency rates at 1, 2, and 3 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% vs 3%; 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 midterm follow-up. Comparative studies with other commercially available covered stents are warranted.

Prophylactic relining for bridging stent compression after thoracoabdominal endovascular aneurysm repair: Myth or reality?

BACKGROUND/OBJECTIVE

Target vessels related complications are one of the most important 'Achille's heel' of complex thoracoabdominal endovascular procedures. The aim of this report is to describe a case of spontaneous bridging stent-graft (BSG) delayed expansion in a patient treated for type III mega-aortic syndrome, associated with aberrant right subclavian artery and independent origin of the two common carotid arteries.

METHODS

The patient underwent different surgical procedures (ascending aorta replacement with carotid arteries debranching, bilateral carotid-subclavian bypass with subclavian origins embolization and TEVAR in zone 0, associated with a multibranched thoracoabdominal endograft deployment). Visceral vessels stenting was performed using balloon-expandable BSGs for celiac trunk, superior mesenteric artery and right renal artery, while for the left renal artery a 6 × 60 mm self-expandable BSG was deployed.The first follow-up (FU) by computed tomography angiography (CTA) showed a severe compression of the left renal artery BSG. Considering the challenging access to the directional branches (SAT's debranching and a tightly curve of the steerable sheath inside the branched main body), a conservative treatment was considered, performing a control CTA after 6-months.

RESULTS

Six months later, the CTA demonstrated a spontaneous expansion of the BSG, with a two-fold increase in the minimum stent diameter, excluding the need for new reinterventions such as angioplasty or BSG relining.

CONCLUSIONS

Directional branch compression is a frequent complication during BEVAR; however, in this case, it spontaneously resolved after 6 months, without the need for secondary adjunctive procedures. Further studies on predictor factors for BSG related adverse events and regarding spontaneous delayed BSGs' expansion mechanisms are needed.

Fenestrierte und verzweigte endovaskuläre Aortenprothesen

Hintergrund

Komplexe abdominelle aortale Pathologien, welche die Abgänge der Viszeralarterien miterfassen und bei denen kein adäquater proximaler Hals gegeben ist, können heute mittels fortgeschrittener FEVAR/BEVAR-Technik („fenestrated/branched endovascular aneurysm repair“) mit ähnlicher Sicherheit und vergleichbaren Erfolgsraten behandelt werden wie infrarenale Pathologien mit konventionellem EVAR.

Methodische Innovationen und Probleme

Zur Versorgung der Viszeralarterien können Fenestrierungen (bei Abgang der Viszeralarterie aus der nichtdilatierten Aorta) oder Verzweigungen (bei Abgang aus der dilatierten Aorta) verwendet werden. Beide Arten von Öffnungen werden mit Verbindungsstentgrafts (VSG) zu den Viszeralarterien abgedichtet. Mehrere Hersteller bieten fenestrierte oder verzweigte Endoprothesen an, wobei diese nur in Einzelfällen CE-zertifiziert und überwiegend in Europa als individuelle Sonderanfertigungen patientenbezogen erhältlich sind. Dies setzt eine entsprechende Lieferzeit voraus, was die Behandlung akuter Patienten mit solchen Prothesen unmöglich macht. Es liegen allerdings zwei Produkte von vierfach verzweigten Endoprothesen vor, die einen größeren Bereich der anatomischen Gegebenheiten bei thorakoabdominellen Aneurysmen auch im Akutfall abdecken und behandelbar machen. Sämtliche FEVAR- und BEVAR-Hauptkörper benötigen VSG, die durchgehend von Fremdherstellern stammen und von denen gegenwärtig noch kein einziges Produkt für diese Anwendung zertifiziert ist.

Empfehlungen

Da Probleme an Verbindungsstentgrafts eine wesentliche Ursache für Reinterventionen sind, sollte in der Nachsorge Knickbildungen und Brüchen an diesen Verbindungsstents besonderes Augenmerk geschenkt und von der Verwendung einschichtiger Designs beim BEVAR abgesehen werden.