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.

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.

Thoracoabdominal aortic aneurysm repair: current endovascular perspectives

Thoracoabdominal aneurysms account for roughly 3% of identified aneurysms annually in the United States. Advancements in endovascular techniques and devices have broadened their application to these complex surgical problems. This paper will focus on the current state of endovascular thoracoabdominal aneurysm repair, including specific considerations in patient selection, operative planning, and perioperative complications. Both total endovascular and hybrid options will be considered.

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.

Renal autotransplantation as savior in hybrid surgery for aortic aneurysm repair

Renal autotransplantation is a safe and effective procedure to reconstruct the urinary tract. The current indications for autotransplantation include renal vascular disease, severe ureteral damage, tumours of the kidney and ureter, complex nephrolithiasis and retroperitoneal fibrosis. We report a rare case where we had to perform renal autotransplantation along with hybrid surgery for aortic aneurysm repair. To our knowledge, this is the first case report of its kind for this specific condition.

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.

Multiple aneurysm repair: hybrid approach to chronic dissection around visceral branches

The present case report details our experience with the hybrid approach for multiple aneurysms in the aortic arch, thoracoabdominal aorta, and around the aortic bifurcation. Total arch replacement for the arch aneurysm under hypothermic cardiopulmonary bypass with antegrade cerebral perfusion was the first stage of aneurysm repair. Five months later, bifurcated graft replacement with debranching of four abdominal branches was undertaken as the second stage of treatment. Finally, stent-graft repair for chronic dissection of the thoracoabdominal aorta was performed utilizing a Gore-Tex Tag endovascular prosthesis. Over 7 months of treatment, all aneurysms were excluded from the aortic blood flow and pressure without abdominal organ dysfunction except a transiently elevated total bilirubin level. Although the patient had an episode of minor gastrointestinal bleeding after discharge, he is currently leading a normal life without limitations at home 5 months after the stent-graft repair.

Changing Indications and Outcomes for Open Abdominal Aortic Aneurysm Repair since the Advent of Endovascular Repair

The indications for open abdominal aortic aneurysm (AAA) repair have changed with the development of endovascular techniques. The purpose of this study is to clarify the indications and outcomes for open repair since endovascular aneurysm repair (EVAR) and to compare contemporary AAA repair with the pre-EVAR era. Patients undergoing open AAA repair were identified; the demographics, outcomes, and indications for open repair were reviewed. Outcomes were compared based on indication for open repair in the EVAR era and between the pre-EVAR and EVAR eras. Open indications in the EVAR era included: age younger than 65 years with minimal comorbidities (AGE, n = 24 [9.8%]), unfavorable anatomy (ANAT, n = 146 [59.3%]), aortoiliac occlusive disease (AIOD, n = 38 [15.4%]), and miscellaneous (OTHER, n = 38 [15.4%]). Mortality (30-day and 5-year) was affected by indication: AGE = 0 and 0 per cent, ANAT = 4.1 and 49.7 per cent, AIOD = 13.5 and 32.3 per cent, and OTHER = 5.3 and 41.8 per cent. Age, sex, race, coronary artery disease, and peripheral artery disease were similar between the pre-EVAR and EVAR eras. EVAR-era patients had more diabetes mellitus, hypertension, and hyperlipidemia and longer operative time. Mortality was not different, but complication rates were lower in the pre-EVAR era (23.7 vs 43.5%, P = 0.025). Patients undergoing open AAA repair in the EVAR era have more comorbidities, longer operative times, and more complications. Outcomes for EVAR-era patients are affected by the indication for open repair. A preference for open repair in younger patients with minimal comorbidities is justified.