Hybrid Repair of Thoracoabdominal Aortic Aneurysms Involving the Visceral Vessels: Comparative Analysis Between Number of Vessels Reconstructed, Conduit, and Gender

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.

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.

Comparison of Clinical Outcomes Following One versus Two Stage Hybrid Repair of Thoraco-Abdominal Aortic Aneurysms: A Comprehensive Meta-Analysis

OBJECTIVE

For thoraco-abdominal aortic aneurysms (TAAA), it is unclear whether it is better to perform hybrid repair in one (single) or two stages (staged). This study aimed to compare the clinical outcomes of single vs. staged hybrid repair of TAAA.

METHODS

The Medline, Embase, and Cochrane Databases (1 January 1994 to 11 May 2020) were searched for studies on hybrid repair of TAAA. Cohort studies and case series reporting outcomes of single and staged hybrid repair of TAAA were eligible for inclusion. The Newcastle-Ottawa scale and an 18 item tool were used to assess the risk of bias. The primary outcome was 30 day mortality, and the secondary outcomes included post-operative complications, overall survival, and other mid term events. A random effects model was used to calculate pooled estimates.

RESULTS

A total of 37 studies was included in the meta-analysis. The quality assessment of the included studies suggested low or moderate risk of bias. The pooled estimates for aneurysm rupture and death during stage interval were 2% (95% CI 0%-4%, I² = 0%) and 4% (95% CI 2%-7%, I² = 0%), respectively. Single repair was associated with a significantly higher 30 day risk of death when compared with patients who completed staged procedures successfully (OR 2.64, 95% CI 1.36-5.12, I² = 0%). Staged repair also had lower incidence of major adverse cardiac events (MACE) (single: 10%, 95% CI 5%-16%; staged: 2%, 95% CI 0%-5%) and intestinal complications (single: 15%, 95% CI 8%-25%; staged: 3%, 95% CI 1%-6%). For mid term outcomes, single and staged repair had comparable 12 month overall survival, aneurysm related mortality, rate of re-intervention, and graft patency.

CONCLUSION

Two stage hybrid repair may represent a better choice for patients with controlled risk of aneurysm rupture, because it can provide lower 30 day mortality risks, MACE, and intestinal complications, as well as comparable mid term outcomes. Randomised controlled trials are needed to ascertain the effect of repair staging in patients for elective TAAA.

Gender differences in outcomes after aortic aneurysm surgery should foster further research to improve screening and prevention programmes

Background Gender-related biases in outcomes after thoracic aortic surgery are an important factor to consider in the prevention of potential complications related to aortic diseases and in the analysis of surgical results. Methods The aim of this study is to provide an up-to-date review of gender-related differences in the epidemiology, specific risk factors, outcome, and screening and prevention programmes in aortic aneurysms. Results Female patients affected by aortic disease still have worse outcomes and higher early and late mortality than men. It is difficult to plan new specific strategies to improve outcomes in women undergoing major aortic surgery, given that the true explanations for their poorer outcomes are as yet not clearly identified. Some authors recommend further investigation of hormonal or molecular explanations for the sex differences in aortic disease. Others stress the need for quality improvement projects to quantify the preoperative risk in high-risk populations using non-invasive tests such as cardiopulmonary exercise testing. Conclusions The treatment of patients classified as high risk could thus be optimised before surgery becomes necessary by means of numerous strategies, such as the administration of high-dose statin therapy, antiplatelet treatment, optimal control of hypertension, lifestyle improvement with smoking cessation, weight loss and careful control of diabetes. Future efforts are needed to understand better the gender differences in the diagnosis, management and outcome of aortic aneurysm disease, and for appropriate and modern management of female patients.

Debranching aortic surgery

Conventional open surgery still remains as the gold standard of care for aortic arch and thoracoabdominal pathology. In centers of excellence, open repair of the arch has been performed with 5% immediate mortality and a low rate of complications; however overall mortality rates are around 15%, being up to 40% of all patients rejected for treatment due to their age or comorbidities. For thoracoabdominal aortic pathology, data reported from centers of excellence show immediate mortality rates from 5% to 19%, spinal cord ischemia from 2.7% to 13.2%, and renal failure needing dialysis from 4.6% to 5.6%. For these reasons, different alternatives that use endovascular techniques, including debranching procedures, have been developed. The reported results for hybrid debranching procedures are controversial and difficult to interpret because series are retrospective, heterogenic and including a small number of patients. Clearly, an important selection bias exists: debranching procedures are performed in elderly patients with more comorbidities and with thoracoabdominal aortic aneurysms that have more complex and extensive disease. Considering this fact, debranching procedures still remain a useful alternative: for aortic arch pathology debranching techniques can avoid or reduce the time of extracorporeal circulation (ECC) or cardiac arrest which may be beneficial in high-risk patients that otherwise would be rejected for treatment. And compared to pure endovascular techniques, they can be used in emergency cases with applicability in a wide range of anatomies. For thoracoabdominal aortic aneurysms, they are mainly useful when other lesser invasive endovascular options are not feasible due to anatomical limitations or when they are not available in cases where delaying the intervention is not an option.

Multibranched Stent-Grafts for the Treatment of Thoracoabdominal Aortic Aneurysms

Purpose: To evaluate the available literature on endovascular repair of thoracoabdominal (TAAA) and pararenal aortic aneurysms (PRAA) using multibranched stent-grafts. Methods: MEDLINE, EMBASE, and Cochrane databases were searched between January 2001 and June 2015 to identify articles related to the use of multibranched stent-grafts for the treatment of TAAA and PRAA. Articles with <4 cases and those on juxtarenal aortic aneurysms were excluded. Meta-analyses were conducted to evaluate 30-day mortality, all-cause mortality, spinal cord ischemia, renal insufficiency, endoleak, target vessel patency, and reintervention. Of 370 articles screened, only 4 articles encompassing 185 patients (mean age 71.1 years; 137 men) were aligned with the inclusion criteria. There were 23 PRAAs; the mean aneurysm diameter was 64.5 mm. The Crawford TAAA classification was 10 type I, 47 type II, 37 type III, 58 type IV, and 9 type V; there was 1 Stanford type B dissection in association with a large TAAA. Results of the meta-analyses are reported as proportions and 95% confidence interval (CI). Results: Pooled analysis indicated a technical success rate of 98.9%. As study heterogeneity was significant, random effects models were used for meta-analysis. The rate for 30-day mortality was 9% (95% CI 3% to 19%), for all-cause mortality 27% (95% CI 17% to 38%), endoleaks 10% (95% CI 1% to 25%), target vessel patency 98% (95% CI 95% to 99%), SCI 17% (95% CI 1% to 26%), irreversible SCI 6% (95% CI 3% to 10%), renal insufficiency 15% (95% CI 0.8% to 41%), and reinterventions 21% (95% CI 4% to 47%). Conclusion: Use of multibranched stent-grafts in the treatment of TAAAs and PRAAs appears to be feasible and safe based on satisfactory early outcomes in the limited literature available to date. Long-term surveillance and further studies are essential to determine the durability of this technique.

Combined open and endovascular treatment of thoracoabdominal aortic pathologies: a systematic review and meta-analysis

BACKGROUND

A combined open-endovascular technique has emerged as an alternative treatment option for thoracoabdominal pathologies. However, reported experiences from various medical centers have been contradictory and heterogeneous. The aim of this study is to assess the mortality rate and various complication rates associated with this approach.

METHODS

An electronic health database search was performed on all articles published up to March of 2012 describing combined open-endovascular repair of thoracoabdominal pathologies. Studies were included in the meta-analysis if they had ≥10 patients and reported the basic outcome criteria. End points of the meta-analysis were defined as primary technical success, endoprosthesis related complications, 30-day/in-hospital mortality, symptoms of spinal cord ischemia (SCI) and irreversible paraplegia, permanent renal function impairment, and other major complications.

RESULTS

Fourteen studies were deemed eligible for this meta-analysis with a total of 528 patients (68.0% male, mean age 70.5 years). The mean follow-up period was 34.2 months. The pooled estimate for primary technical success and visceral graft patency was 95.4% and 96.5% respectively. An endoleak developed in 106 (21.1%) patients in whom both stages had been completed. The pooled rate for symptomatic SCI was 7.0% and for irreversible paraplegia 4.4%. The pooled proportion for permanent renal failure was 7.0% and for mesenteric ischemia 4.5%. Prolonged respiratory support and cardiac complications were observed in a pooled rate of 7.8% and 4.6% respectively. The meta-analysis for 30-day/in-hospital mortality revealed a pooled rate of 14.3%.

CONCLUSIONS

Although the hybrid technique for thoracoabdominal aortic pathology provides a less invasive approach, the technique is still associated with a considerable morbidity and mortality rates. High risk patients unfit to withstand open repair, are equally likely to suffer significant complications with the hybrid procedure. The choice of the optimal treatment strategy for thoracoabdominal pathologies should be carefully made on a patient to patient basis, assessing the clinical fitness and the anatomical suitability of each patient. The hybrid approach should be reserved for high volume centers with accumulated experience and high standards of perioperative management.

Clinical outcomes of single versus staged hybrid repair for thoracoabdominal aortic aneurysm

OBJECTIVE

We investigated the outcomes of hybrid repair of thoracoabdominal aortic aneurysms and performed meta-analyses and meta-regressions to assess whether the number of stages during hybrid repair is associated with mortality.

METHODS

Review methods were according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The primary outcome was 30-day mortality. Secondary outcomes of procedural and clinical success were reported descriptively. Meta-analyses, meta-regressions, and logistic regressions were performed to estimate the odds ratio (OR) describing the association between the staging of the operation and in-hospital death.

RESULTS

We included 19 studies of 660 patients. Procedures were single-staged in 288 patients and staged in 372. Perioperative mortality ranged from 0% to 44.4%, and spinal cord ischemia ranged from 0% to 15.3%. After a mean follow-up of 26 months (range, 6-88.5 months), the overall mortality was 20.8%. The meta-regression of all studies' summary data (OR, 0.64; 95% confidence interval [CI], 0.19-2.16; P = .45; I(2) = 0.42) and a meta-regression where mortality rates in four studies were stratified by operative staging (OR, 0.57; 95% CI, 0.24-1.36; P = .19; I(2) = 0.38) supported a two-stage procedure but failed to reach statistical significance. Logistic regressions of individual patient data from a single center demonstrated evidence that a staged procedure was safer (adjusted OR, 0.04; 95% CI, 0.00-0.96; P < .05).

CONCLUSIONS

Hybrid repair of thoracoabdominal aortic aneurysms may reduce early morbidity and mortality even in a group considered high risk for open surgery but still carries risks of perioperative complications. This study suggested advantages to a staged procedure, but statistically significant evidence is lacking. Prospective data are still needed to optimize hybrid repair and best define its role.

Diseases of the thoracic aorta in women

Women have now equaled or surpassed men in the number of cardiovascular deaths per year in published statistics. In 2006, according to the National Center for Health Statistics and the Center for Disease Control, cardiovascular disease was the cause of death in 428,906 women (35% of all deaths in women) and in 394,840 men (33% of all deaths in men). Of those numbers, it was estimated that 5506 women (0.4% of all deaths in women) and 7732 men (0.6%) died because of aortic aneurysm or dissection. Currently, aortic disease ranks as the 19th leading cause of death with reported increases in incidence. Historically, aortic disease is thought to affect men more frequently than women with a varying reported gender ratio. Gender bias has long been implicated as an important factor, but often overlooked, in the analysis and interpretation of cardiovascular diseases outcome, in part, because of the under-representation of women in clinical trials and studies. In this section, we provide an up-to-date review of the epidemiology and management of common diseases of the thoracic aorta, focusing on the differences and similarities in women and men.

Long-term complications in two patients after aortoaortic bypass for midaortic syndrome

The midaortic syndrome (MAS) refers to descending thoracic and abdominal aortic coarctation, which is rare and most common in the pediatric population. Open surgical repair, often with aortoaortic bypass, remains a highly effective treatment and is traditionally thought to be definitive despite concerns over patient growth postoperatively. This article presents 2 cases of MAS treated with aortoaortic bypass who developed long-term complications, one related to patient growth and the other to graft-enteric fistula. Consideration must be given to patient growth at operation for MAS, and long-term follow-up is necessary to identify other complications.

Hybrid Open Endovascular Technique for Aortic Thoracoabdominal Pathologies

Background—

Many authors using a hybrid debranching strategy for the treatment of thoracoabdominal pathologies have reported disappointing results and the initial enthusiasm for the technique has given way to criticism and ambiguity. The aim of the present meta-analysis study was to assess the safety and efficacy of the technique in patients with thoracoabdominal aortic aneurysms or other aortic pathologies.

Methods and Results—

A multiple electronic search was performed on all articles describing hybrid open endovascular repair. Separate meta-analyses were conducted for technical success, visceral graft patency, spinal cord ischemia symptoms, renal insufficiency, and other complications as well as 30-day/in-hospital mortality.

Nineteen publications with a total of 507 patients were analyzed. The pooled estimates for primary technical success and visceral graft patency were 96.2% (95% CI, 93.5%–98.2%) and 96.5% (95% CI, 95.2%–97.8%) respectively. A pooled rate of 7.5% (95% CI, 5.0%–11.0%) for overall spinal cord ischemia symptoms was observed; whereas for irreversible paraplegia the pooled rate was 4.5% (95% CI, 2.5%–7.0%). The pooled estimate for renal failure was 8.8% (95% CI, 3.9%–15.5%). The pooled 30-day/in-hospital mortality rate was 12.8% (95% CI, 8.6%–17.0%). During the mean follow-up period of 34.5 (95% CI, 31.5–37.5) months, a total of 119 endoleaks were identified in 111 patients (22.7%).

Conclusions—

The repair of thoracoabdominal pathologies by means of hybrid procedures in patients who are poor surgical candidates is still associated with significant morbidity and mortality rates. Future studies may substantiate whether the technique is amenable to amelioration and improvement.