Comparison of Physician-Modified Fenestrated/Branched Stent-Grafts and Hybrid Visceral Debranching Plus Stent-Graft Placement for Complex Thoracoabdominal Aortic Aneurysm Repair

Techniques in hybrid repair of aortic arch and thoracoabdominal aortic pathologies

INTRODUCTION

Since the mid-1900s, techniques in the repair of aortic arch and thoracoabdominal aortic pathologies have drastically evolved. Open aortic surgical repair was once the sole option for both simple and complex aneurysmal degeneration. Today, a number of minimally invasive and hybrid approaches are now available to assist both the surgeon and patient in tackling this challenging problem.

AREAS COVERED

In this review, we discuss the most current techniques in the repair of these complex pathologies as well as new advances. These include aortic arch and abdominal aortic debranching with endovascular repair, branched stent graft repair, parallel grafting techniques, fenestration techniques, and a hybrid approach to the aforementioned. In addition, we discuss comparative outcomes of these techniques spanning disciplines of both cardiac and vascular surgery.

EXPERT OPINION

The most vital part of the treatment of complex aortic aneurysms is the tailoring of the treatment plan to each patient's unique anatomic and physiologic attributes.

Stent-Assisted Coil Embolization of a Saccular Visceral Aortic Aneurysm: Case Report and Review of the Literature

PURPOSE

We present the results of unconventional endovascular treatment of a voluminous (65 mm) saccular visceral aortic aneurysm in a 78-year-old woman. Patient was deemed unfit for open surgery due to comorbidities. Fenestrated or branched endografting was also excluded due to the small diameter of the aorta, the severe stenosis at the origin of celiac trunk, and the anomalous origin of superior mesenteric artery arising infrarenally.

CASE REPORT

After a preliminary selective angiography of the superior mesenteric artery showing valid anastomotic network with celiac trunk branches, an aortic self-expandable bare stent (Jotec E-XL) was deployed in the visceral aorta. Aneurysm sac embolization (Penumbra detachable Ruby Coils) in a coil-jailing technique was performed. Finally, an aortic cuff endograft (Gore) was deployed immediately above the origin of the left renal artery to cover the wide neck of the saccular aneurysm and improve sac exclusion. Hospital stay was uneventful, computed tomography (CT) at 12-month demonstrated aneurysm shrinkage to 62 mm without images of endoleak. Literature review showed how this technique has successfully been applied to manage similar cases of postsurgical and posttraumatic saccular aortic aneurysms in high-risk patients; however, long-term results are still unknown.

CONCLUSION

Coil-jail technique for the treatment of saccular aortic aneurysms can be considered an alternative when open surgery or conventional endovascular treatment is not feasible. Technical success and mid-term outcomes are promising but strict follow-up is recommended.

CLINICAL IMPACT

This study aims to share the unconventional endovascular treatment of a visceral aortic aneurysm in a patient unfit both for open and traditional endovascular surgery. To the best of our knowledge this is one of the first cases published in Literature, for this reason, a step-by-step video has been created to describe the procedure. Literature review was then performed to analyze midterm results of this technique. Despite being a treatment that is not recommended for conventional cases, the knowledge of endovascular devices and techniques may help to manage or simplify complex aortic diseases.

A systematic review and meta-analysis of total endovascular versus hybrid repair for the treatment of thoracoabdominal aortic aneurysms

OBJECTIVE

Although open repair has been the traditional mainstay therapy for thoracoabdominal aortic aneurysms (TAAAs), it remains a surgical challenge. Recently, hybrid repair (HR) and total endovascular repair (TEVR) have emerged as viable alternatives in treating TAAAs. Thus, we aimed to compare the primary outcomes of in-hospital/30-day mortality, as well as secondary outcomes of postoperative complications including spinal cord ischemia, bowel ischemia, long-term dialysis, myocardial infarction and lower limb ischemia for HR vs TEVR for the treatment of TAAAs. We postulated that TEVR was associated with lower in-hospital and 30-day mortality and postoperative complication rates as compared with HR.

METHODS

Four scientific databases were searched from inception to November 18, 2021. Meta-analyses were performed for the primary and secondary outcomes. This study was conducted in adherence to the PRISMA guidelines.

RESULTS

The search yielded 3312 articles. After a two-stage selection process, five articles were included for final analysis. The in-hospital/30-day mortality rate for TEVR was significantly lower compared with HR (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.20-0.36; P < .00001). TEVR was also associated with reduced bowel ischemia (OR, 0.22; 95% CI, 0.14 -0.35; P < .00001) and long-term dialysis (OR, 0.22; 95% CI, 0.16-0.29; P < .00001). There was, however, no difference in the incidence of spinal cord ischemia (OR, 1.26; 95% CI, 0.74-2.14; P = .39), stroke (OR, 0.65; 95% CI, 0.10-4.20; P = .65), myocardial infarction (OR, 0.60; 95% CI, 0.17-2.05; P = .41), and lower limb ischemia (OR, 0.67; 95% CI, 0.29-1.55; P = .35). Most study outcomes had low heterogeneity. Findings were also robust to sensitivity analysis.

CONCLUSIONS

Compared with the HR, TEVR of TAAAs were associated with lower in-hospital and 30-day mortality, bowel ischemia, and long-term dialysis.

Physician-Modified Stent-Grafts Created in the Three-Dimensionally Aortic Template Have Better Reliability and Greater Alignment With the Target Vessels Than Stent-Grafts Modified Based on Measurements From Computed Tomography

PURPOSE

Physician-modified stent-grafts (PMSG) are widely used, especially when a patient's condition precludes waiting for a custom-made device. In recent years, the modification process has been upgraded using 3-dimensional (3D) aortic templates. Nonetheless, the reliability of PMSG and accuracy of fenestration alignment with the target vessel are not known. Thus, the study is aimed to fulfill the gap in current knowledge.

MATERIALS AND METHODS

Ten computed tomographic (CT) scans of aortic aneurysm previously treated with the fenestrated endovascular repair were selected to 3D-print aortic templates and elastic vessel phantoms. Two vascular surgeons performed fenestrations using the 3D template and modification plan based on CT measurements. Two operators each performed 10 fenestrated stent-grafts in the aortic template and 10 using CT measurements, for a total of 40 fenestrated stent-grafts. Then, stent-grafts were implanted in elastic vessel phantoms, which served to evaluate fenestration alignment with the target vessel. The alignment was judged in a 5-point scale: 0%, 1% to 25%, 26% to 50%, 51% to 75%, and 76% to 100%. The distances between fenestrations served to calculate interobserver variability for both methods. The measurements were processed as interclass correlation coefficient (ICC), Pearson and Spearman correlation, and Bland-Altman plots.

RESULTS

PMSG created with a 3D template had higher interclass correlation coefficient values and Pearson/Spearman correlation than fenestrations created from CT measurements. The rate of fenestration alignment with the target vessel was higher for PMSG created with a 3D template (p=0.007).

CONCLUSIONS

PMSGs created with a 3D template are more reliable and have better fenestration alignment with the target vessel than PMSGs created based on CT measurements.

Debranching abdominal aortic hybrid surgery for aortic diseases involving the visceral arteries

Objective

Aortic diseases involving branches of the visceral arteries mainly include thoracoabdominal aortic aneurysm (TAAA), aortic dissection (AD) and abdominal aortic aneurysm (AAA). The focus of treatment is to reconstruct the splanchnic arteries and restore blood supply to the organs. Commonly used methods include thoracoabdominal aortic replacement, thoracic endovascular aortic repair and hybrid approaches. Hybrid surgery for aortic disease involving the visceral arteries, consisting of visceral aortic debranching with retrograde revascularization of the celiac trunk and renal arteries and using stent grafts, has been previously described and may be considered particularly appealing in high-risk patients. This study retrospectively analyzed recorded data of patients and contrasted the outcomes with those of a similar group of patients who underwent conventional open repair surgery.

Methods

Between 2019 and 2022, 72 patients (52 men) with an average age of 61.57 ± 8.66 years (range, 36-79 years) underwent one-stage debranching abdominal aortic hybrid surgery. These patients, the hybrid group, underwent preoperative Computed Tomographic Angiography (CTA) and had been diagnosed with aortic disease (aneurysm or dissection) involving the visceral arteries and were at high risk for open repair. The criteria used to define these patients as high-risk group who are in the need of hybrid treatment were American Society of Anesthesiologists (ASA) class 3 or 4. In all cases, we accomplished total visceral aortic debranching through a previous visceral artery retrograde revascularization with synthetic grafts (customized Y or four-bifurcated grafts), and aortic endovascular repair with one of two different commercially produced stent grafts (Medtronic® and Lifetech®). In some cases, we chose to connect the renal artery to the artificial vessel with a stent graft (Viabahn) and partly or totally anastomosed. We analyzed the results and compared the outcomes of the hybrid group with those of a similar group of 46 patients (36 men) with an average age 54.15 ± 12.12 years (range, 32-76). These 46 patients, the conventional open group, were selected for having had thoracoabdominal aortic replacement between 2019 and 2022.

Results

In the hybrid group, 72 visceral bypasses were completed, and endovascular repair was successful in all cases. No intraoperative deaths occurred. Perioperative mortality was 2.78%, and perioperative morbidity was 9.72% (renal insufficiency in 1, unilateral renal infarction in 5, Intestinal ischemia in 1). At 1-month postoperative CTA showed 2 endoleaks, one of which was intervened. At follow-up, there were unplanned reoperation rate of 4.29% and 5 (7.14%) deaths. The remaining patients' grafts were patent at postoperative CTA and no endoleak or stent graft migration had occurred. In the conventional open group, 1 died intraoperatively, 4 died perioperatively, perioperative mortality was 10.87% and complications were respiratory failure in 5, intestinal paralysis/necrosis in 4, renal insufficiency in 17, and paraplegia in 2. At follow-up, 5 (12.20%) patients presented with synthetic grafts hematoma 4 (9.76%) patient died, and 6 (14.63%) patients required unplanned reoperation intervention.

Conclusion

Hybrid surgery is technically feasible in selected cases. For aortic diseases involving the visceral arteries, the application of hybrid abdominal aorta debranching can simplify the operation process, decrease the risks of mortality and morbidity in high-risk and high-age populations and decrease the incidence of various complications while achieving ideal early clinical efficacy. However, a larger series is required for valid statistical comparisons, and longer follow-ups are necessary to evaluate the long-term efficacy of hybrid surgery.

Risk factors for target vessel endoleaks after physician-modified fenestrated or branched endovascular aortic repair for postdissection thoracoabdominal aortic aneurysms

OBJECTIVE

Patients with postdissection thoracoabdominal aortic aneurysms (TAAAs) have been more likely to develop endoleaks than those with degenerative TAAAs after fenestrated or branched endovascular aortic repair (F/BEVAR). In the present study, we aimed to determine the risk factors for target vessel (TV)-related endoleaks after visceral segment F/BEVAR for postdissection TAAAs.

METHODS

We performed a retrospective analysis of all patients with degenerative and postdissection TAAAs treated with F/BEVAR between 2017 and 2021. All the patients had undergone computed tomography angiography before and 3 months, 6 months, and annually after discharge. Two experienced vascular surgeons had used data from computed tomography angiography and vascular angiography to judge the presence of endoleaks. The study end points were mortality, aneurysm rupture, and the emergence of and reintervention for TV-related endoleaks.

RESULTS

A total of 195 patients (mean age, 66 ± 10 years; 69% men) had undergone F/BEVAR for 99 postdissection TAAAs and 96 degenerative TAAAs. During a mean follow-up of 16 ± 12 months, we found that the patients with postdissection TAAAs were younger (age, 64 ± 10 years vs 69 ± 9 years; P = .001), had required more prior aortic repairs (58% vs 40%; P = .012), and had had a higher body mass index (26.1 ± 3.4 kg/m² vs 24.8 ± 3 kg/m²; P = .008), a larger visceral segment aortic diameter (47.1 ± 7.5 mm vs 44.5 ± 7.5 mm; P = .016), and more TV-related endoleaks (18% vs 7%; P = .023) compared with those with degenerative TAAAs. Of the 99 patients with postdissection TAAAs, 327 renal-mesenteric arteries were revascularized using 12 scallops, 141 fenestrations, and 174 inner or outer branch stents. A total of 25 TV-related endoleaks were identified among 18 patients during follow-up, including 6 type Ic (retrograde from the distal end of the branch), 3 type IIIb (bridging stent fabric tear), and 16 type IIIc endoleaks (detachment or loose connection of the bridging stent). The patients with an endoleak had had a larger visceral aortic diameter (52.7 ± 6.4 mm vs 45.8 ± 7.2 mm; P < .001) and had undergone revascularization of more TVs (3.7 ± 0.7 vs 3.2 ± 0.9; P = .032). In contrast, true lumen compression did not seem to affect the occurrence of TV endoleaks (39% vs 27%; P = .323). The use of presewn branch stents in the fenestration position was associated with a lower risk of TV-related endoleaks (5% vs 11%; P = .025). In addition, TVs derived entirely or partially from the false lumen were more prone to the development of endoleaks after reconstruction (19% vs 4% [P < .001]; and 15% vs 4% [P = .047], respectively).

CONCLUSIONS

We found that patients with postdissection TAAAs were more likely to have TV-related endoleaks after F/BEVAR in the visceral region than those with degenerative TAAAs. Additionally, patients with a larger aortic diameter and a greater number of fenestrations in the visceral region were more likely to have experienced TV-related endoleaks. Branch vessels deriving from the false lumen were also more likely to develop endoleaks after reconstruction, and prefabricated branch stents were related to a lower possibility of TV-related endoleaks.

Results of the North American Complex Abdominal Aortic Debranching (NACAAD) Registry

BACKGROUND

Hybrid debranching repair of pararenal and thoracoabdominal aortic aneurysms was initially designed as a better alternative to standard open repair, addressing the limitations of endovascular repair involving the visceral aorta. We reviewed the collective outcomes of hybrid debranching repairs using extra-anatomic, open surgical debranching of the renal-mesenteric arteries, followed by endovascular aortic stenting.

METHODS

Data from patients who underwent hybrid repair in 14 North American institutions during 10 years were retrospectively reviewed. Society of Vascular Surgery scores were used to assess comorbidity risk. Early and late outcomes, including mortality, morbidity, reintervention, and patency were analyzed.

RESULTS

A total of 208 patients (118 male; mean age, 71±8 years old) were treated by hybrid repair with extraanatomic reconstruction of 657 renal and mesenteric arteries (mean 3.2 vessels/patient). Mean aneurysm diameter was 6.6±1.3 cm. Thoracoabdominal aortic aneurysms were identified in 163 (78%) patients and pararenal aneurysms in 45 (22%). A single-stage repair was performed in 92 (44%) patients. The iliac arteries were the most common source of inflow (n=132; 63%), and most (n=150; 72%) had 3 or more bypasses. There were 30 (14%) early deaths, ranging widely across sites (0%-21%). A Society of Vascular Surgery comorbidity score >15 was the primary predictor of early mortality (P<0.01), whereas mortality was 3% in a score ≤9. Early complications occurred in 140 (73%) patients and included respiratory complications in 45 patients (22%) and spinal cord ischemia in 22 (11%), of whom 10 (45%) fully recovered. At 5 years, survival was 61±5%, primary graft patency was 90±2%, and secondary patency was 93±2%. The most significant predictor of late mortality was renal insufficiency (P<0.0001).

CONCLUSIONS

Mortality after hybrid repair and visceral debranching is highly variable by center, but strongly affected by preoperative comorbidities and the centers' experience with the technique. With excellent graft patency at 5 years, the outcomes of hybrid repair done at centers of excellence and in carefully selected patients may be comparable (or better) than traditional open or even totally endovascular approaches. However, in patients already considered as high-risk for surgery, it may not offer better outcomes.

Safety and Efficacy of Intentional Celiac Artery Coverage in Endovascular Management of Thoracoabdominal Aortic Diseases: A Systematic Review and Meta-analysis

PURPOSE

Thoracic endovascular aortic aneurysm repair (TEVAR) has emerged as an attractive alternative option in the treatment of thoracoabdominal aortic aneurysm (TAAA) diseases, reporting lower morbidity and mortality rates compared with open or hybrid repair. A challenging situation arises when the aneurysm involves the celiac artery (CA), precluding a safe distal landing zone. We investigated the safety and efficacy of CA coverage in the treatment of complex TAAA diseases during endovascular management.

MATERIALS AND METHODS

A review of the literature was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. The electronic bibliographic sources searched were MEDLINE and SCOPUS databases. Primary outcomes of interest were perioperative and 30-day mortality. Any type of endoleak, mesenteric ischemia, perioperative spinal cord ischemia, and reintervention rates were secondary end points. A random-effects meta-analysis was performed. Summary statistics of event risks were expressed as proportions and 95% confidence interval (CI).

RESULTS

Ten observational cohort studies published between 2009 and 2020, reporting a total of 175 patients, were eligible for quantitative synthesis. Indications for TEVAR were primary TAAAs in 82% of patients, aortic dissection in 14% of patients, type Ib endoleak after previous endograft deployment in 3% of patients, and penetrating aortic ulcer in 1 patient. Reintervention rate was 9% (95% CI, 4%-20%) and spinal cord ischemia was 7% (95% CI, 4%--12%). Type II endoleak was the predominant type of endoleak in 10% of patients (95% CI, 4%-22%), followed by type I endoleak in 5% of patients (95% CI, 2%-12%) and type III endoleak in 1% (95% CI, 0%-16%) of patients. Mesenteric ischemia occurred in 6% of patients (95% CI, 3%-10%). Thirty-day mortality was 5% (95% CI, 2%-13%) and the pooled estimate for overall mortality was 21% (95% CI, 14%-31%).

CONCLUSIONS

Celiac artery coverage during TEVAR is a challenging but feasible option for the treatment of TAAA diseases, providing acceptable morbidity and mortality rates. Demonstration of adequate visceral collateral pathways before definitive CA coverage is the sine quo non for the success of the technique.

Total abdominal debranching hybrid thoracoabdominal aortic aneurysm repair versus chimneys and snorkels

Open thoracoabdominal aortic aneurysm (TAAA) repair remains a surgical challenge. Hybrid and total endovascular repair have emerged as alternatives in treating TAAA. Total endovascular TAAA repair may be best performed with branched/fenestrated stent grafts. However, these technologies are not yet widely available. Thus, currently total endovascular TAAA repair using the chimney/snorkel techniques is considered a viable option in many centers.

In this article, we briefly review 2 readily available techniques with off-the-shelf devices, hybrid procedure using total abdominal debranching, and total endovascular repair using chimney/snorkel procedures. The hybrid TAAA repair avoids thoracotomy but requires laparotomy and carries high morbidity and mortality (eg, operative mortality, 4%-26% and renal failure, 4%-26%), comparable to traditional open repair. The staged hybrid approach has been proposed to minimize the invasiveness of the procedure, whereas the associated risk of interval aortic deaths is not negligible. Total endovascular repair reduces the morbidity and mortality after TAAA repair (eg, operative mortality, 3%-20% and renal failure, 0%-20%). However, it is technically demanding and the risks of future reinterventions—and need for repetitive surveillance—is inevitable (eg, immediate type I endoleak, 7%-16% and 1-year branch patency, 93%-98%). Currently, there are not enough data to determine which less-invasive option for open repair in patients with TAAA is superior. These alternatives should complement each other and be applied to carefully selected populations as a part of the overall toolbox in treating TAAA.

Gonadal vein as a bypass conduit for arterial reconstruction during an aortic debranching repair of a paravisceral aortic aneurysm

We report a case of a hybrid aortic debranching procedure for repair of a paravisceral inflammatory aortic aneurysm. Vein grafts were chosen over prosthetics because of concern for infection as a possible etiology. The gonadal vein was successfully used as a vein graft between the right common iliac artery and the right renal artery before aortic endograft placement.