Midterm Outcomes for Endovascular Repair of Thoracoabdominal Aortic Aneurysms

Expert-Based Narrative Review on Contemporary Use of an Off-The-Shelf Multibranched Endograft for Endovascular Treatment of Thoracoabdominal Aortic Aneurysms: Device Design, Anatomical Suitability, Technical Tips, Perioperative Care, Clinical Applications, and Real-World Experience

Advanced endovascular techniques, such as fenestrated stent grafts, are nowadays available that permit minimally invasive treatment of complex abdominal aortic aneurysms. However, thoracoabdominal aortic aneurysm patients have anatomic limitations to fenestrated stent-grafts given a large lumen, that is, the gap between the endograft and the inner aortic wall. This has led to the development of branched endovascular aneurysm repair as the ideal option for such patients. The Zenith t-Branch multibranched endograft (Cook Medical, Bloomington, IN), which has been commercially available in Europe to treat thoracoabdominal aortic aneurysm since June 2012, represents a feasible off-the-shelf alternative for treatment of such pathologies, especially in the urgent setting, for patients who cannot wait the time required for manufacturing and delivery of custom-made endografts. The device's anatomical suitability should be considered, especially for female patients with smaller iliofemoral vessels. Several tips may help deal with particularly complex scenarios (such as, for instance, in case of narrow inner aortic lumens or when treating patients with failure of prior endovascular aneurysm repair), and a broad array of techniques and devices must be available to ensure technical and clinical success. Despite promising early outcomes, concerns remain particularly regarding the risk for spinal cord ischemia and further assessment of long-term durability is needed, including the rate of target vessel instability and need for secondary interventions. As the published evidence mainly comes from retrospective registries, it is likely that reported outcomes may suffer from an intrinsic bias as most procedures reported to date have been carried out at high-volume aortic centers. Nonetheless, with the never-ceasing adoption of new and refined techniques, outcomes are expected to ameliorate.

Technical Aspects and Outcome of Multi-Staged and Single-Staged Thoracoabdominal Fenestrated Endovascular Aortic Repair

PURPOSE

In some cases of endovascular thoracoabdominal or juxtarenal aortic aneurysm repair, a thoracic endograft in combination with a fenestrated renovisceral device may be needed in order to create a sufficient proximal landing zone. This study aimed to evaluate the technical aspects and postoperative morbidity of a single- or 2-stage approach.

METHODS

Eighty-seven consecutive patients undergoing thoracic endovascular aortic repair (TEVAR) in combination with elective fenestrated repair (fenestrated endovascular aortic repair [FEVAR]; fenestrated Anaconda device) from 2015 to 2022 were included in this retrospective bicentric study. Underlying pathologies, aortic morphology, technical details, and postoperative morbidity were recorded.

RESULTS

Single-staged ("1S," n=61) and 2-staged ("2S," n=26) interventions were compared. Indications were thoracoabdominal aneurysms (TAAAs) (Crawford I-IV) (n=56, 64%) and juxtarenal aneurysms (n=31, 36%). In 2S, the proportion of TAAA was higher than in 1S (2S: 77%, 1S: 59%; p=0.001). In 2S, the covered length of the descending aorta was longer (1S: 128±60 mm, 2S: 202±64 mm; p=0.003). Temporary aneurysm sack perfusion (TASP) was established in 11 (18%) of 1S and 1 (4%) of 2S patients (p=0.079), as well as cerebrospinal fluid (CSF) drainage catheter in 48 (79%) of 1S and 19 (73%) of 2S. The rate of spinal cord ischemia (SCI) and the severity of SCI were not different in both groups, with a total of 3 cases of persisting paraplegia. The rate of access complications was higher in 2S (n=6, 23%) than in 1S (n=4, 7%; p=0.027). Postoperative 30 day morbidity did not significantly differ in both groups and neither did 30 day mortality (4.6% in 1S vs 3.8% in 2S; p=0.083).

CONCLUSION

The combination of TEVAR and FEVAR using a fenestrated endograft is feasible and safe. Aortic morphology does not change significantly after endovascular repair. A single-staged strategy is feasible with excellent results, especially in Crawford IV, Crawford V, or juxtarenal aneurysms. Two-staged repair is recommended in cases with long aortic coverage and a higher American Society of Anesthesiologists (ASA) class. Follow-up data are needed to evaluate the long-term stability of the TEVAR/FEVAR interconnection.

CLINICAL IMPACT

Our study has revealed the safety and efficacy of the combination of TEVAR and FEVAR in the treatment of TAAAs and juxtarenal aneurysms with compromised supravisceral landing zones. A single-staged concept is not necessary in all cases. Staged procedures may reduce postoperative morbidity in cases with long aortic coverage and higher ASA class.

Systematic Review and Meta-analysis of Short-term and Mid-term Outcomes After Use of t-Branch Off-the-shelf Multibranched Endograft for Elective and Urgent Treatment of Thoracoabdominal Aortic Aneurysms

OBJECTIVE

To conduct a meta-analysis to assess the safety and efficacy of t-Branch off-the-shelf multibranched endograft for the treatment of thoracoabdominal aortic aneurysm (TAAA).

DATA SOURCES

PubMed, Embase, and Web of Science.

REVIEW METHODS

Online databases were searched from June 2012 to March 2023. The data were pooled together using a random-effects model of proportions. The outcomes overall included technical success, spinal cord ischemia, target vessel occlusion, type I or III endoleak, reintervention, early mortality (30-day), and mid-term outcomes. Subgroup meta-analyses and meta-regression were performed to explore variation among studies.

RESULTS

A total of 15 studies containing 1238 patients were included in the meta-analysis. The overall study quality assessment was found to be moderate to good. The pooled technical success was 97.0% (95% confidence interval [CI]=95.5-98.6, I2=53.01%, 1185/1238 cases, 15 studies). Overall, early mortality was 7.3% (95% CI=4.4-10.1, I2=74.48%, 124/1238 cases, 15 studies). Early spinal cord ischemia was 13.4% (95% CI=9.6-17.2, I2=67.24%, 160/1238 cases, 15 studies), and early type I or III endoleak was 6.0% (95% CI=3.4-8.5, I2=53.71%, 68/1032 cases, 9 studies). Mid-term outcomes showed target vessel occlusion was 4% (95% CI=1.4-6.5, I2=65.18%, 28/528 cases, 10 studies, 5-21.2 months), type I or III endoleak was 4.7% (95% CI=2-7.5, I2=49.74%, 38/512 cases, 10 studies, 5-21.2 months), reintervention was 11.2% (95% CI=8.1-14.3, I2=31.06%, 85/650 cases, 10 studies, 5-21.2 months), and pooled mortality was 13.9% (95% CI=7.2-20.7, I2=76.32%, 84/550 cases, 11 studies, 5-21.2 months). Meta-regression found a significant linear association between higher technical success and earlier publication year (p=0.014) and studies with anatomic inclusion criteria (p=0.037). Urgent patients (p=0.021) and later publication year (p=0.048) were significantly associated with higher early mortality.

CONCLUSION

The use of the off-the-shelf t-Branch multibranched endograft for elective or urgent endovascular TAAA repair is associated with high technical success rates and proved to be safe and effective at early and mid-term follow-up. However, the heterogeneity between the included studies is high, and prospective, randomized studies along with future larger studies with long-term follow-up are needed.

CLINICAL IMPACT

The Zenith t-Branch (Cook Medical, Bloomington, Ind) was approved as a commercially available device in Europe in June 2012. Although a decade has past, the outcomes of t-Branch have rarely been synthesized at the global level. This meta-analysis included 15 studies containing 1238 patients. The meta-analyses included technical success, major adverse events, reintervention, early mortality, and mid-term outcomes. The outcome was very meaningful and representative for the use of t-Branch. It is helpful for endovascular surgeons to make decisions on the treatment of TAAA patients.

Suitability of current off-the-shelf devices for endovascular TAAA repair: a systematic review

INTRODUCTION

The aim of the present study is to perform a systematic review of published papers regarding the suitability of the current off-the-shelf (OTS) devices for endovascular thoracoabdominal aortic aneurysm (TAAA) repair.

EVIDENCE ACQUISITION

A systematic review of the MEDLINE database via PubMed was performed in March 2023. All studies reporting the outcomes of the three currently available OTS stent-grafts: the Zenith t-Branch (Cook Medical, Bloomington, IN, USA), the Gore Excluder thoracoabdominal branch endoprosthesis (TAMBE; W.L. Gore & Associates, Flagstaff, AZ, USA) and the E-nside Multibranch Stent-Graft System (Artivion, Kennesaw, GA, USA), were retrieved and further analyzed. The main endpoints were technical success, reintervention rate, and primary branch patency. Theoretical feasibility studies of these OTS devices were also included and separately analyzed.

EVIDENCE SYNTHESIS

A total of 19 studies were published between 2014 and 2023. Thirteen clinical studies and six theoretical feasibility studies were included. Eleven studies reported the clinical outcomes of the t-Branch stent-graft, one detailed the observational results of the use of the E-nside endoprosthesis, and one described the TAMBE stent-graft results. The following data primarily involve the t-Branch device outcomes. A total of 1131 patients that underwent aneurysm repair using an OTS stent-graft were identified. Among those, 1002, 116 and 13 patients received a t-Branch, E-nside, and TAMBE stent-grafts, respectively. A total of 767 (67.8%) were men, with a mean age of 71.6±7.4 years old, and a mean Body Mass Index (BMI) of 26.3±3.8 kg/m2. Technical success ranged from 64% to 100%. A total of 4172 target visceral vessels (TVV) were planned for bridging, with a success rate ranging from 92 to 100%. The total of early and late reinterventions reported were 64 and 48, respectively, mainly due to endoleaks and visceral branch occlusions. Among the theoretical feasibility studies, six described the feasibility of the t-Branch device in a total of 661 patients, two described the E-nside and the TAMBE devices feasibility comprising 351 patients for each stent-graft. The overall feasibility of the t-Branch device varied from 39% to 88%, the E-nside from 43% to 75%, and the TAMBE stent-graft ranged from 33% to 94%.

CONCLUSIONS

This systematic review demonstrated a good suitability for the use of OTS endografts for the treatment of TAAA.