Thoracoabdominal and Arch Aneurysm, Branched Repair, and Spinal-Cord Protection

24.1Repair selection starts with guideline indication and anatomy

Thoracoabdominal and arch aneurysm repair sits at the most complex end of vascular surgery, and the decision sequence is best run by a combined aortic team rather than by an individual operator choosing a modality in isolation. The first question is whether repair is owed. Current society documents — most recently the ESVS 2026 thoracoabdominal update European Society Vascular 2026 alongside the ACC/AHA 2022 thoracic guideline ACC/AHA 2022, the ACR 2023 imaging guidance, and the older but still operative ESVS 2017 thoracic guideline Editor's Choice Management 2017 — converge on indication frameworks built from symptoms, growth, morphology, genetic-aortopathy status, and anatomic extent, with society-specific class/level wording that differs between guidelines ACR Appropriateness Criteria 2023 · Management Ascending Aorta 2022.

Anatomic extent is named with the Crawford classification (extent types I–IV), which groups thoracoabdominal aneurysms by how much of the descending thoracic and abdominal aorta is involved; the modified (Safi) classification adds extent V. Greater extent means more intercostal and visceral reconstruction and a higher risk of spinal-cord ischemia — Crawford extent II, running from the left subclavian artery to below the renal arteries, is the most extensive and carries the highest risk — so extent, not operator preference, anchors the repair plan.

Once indication is established the more interesting question is which repair path is realistic for this specific patient. The variables that move the decision are anatomic and physiologic, not preferential: proximal and distal landing zones, visceral and renal branch geometry, iliac and femoral access, renal reserve and the cost of any added contrast or ischemia, cardiac and pulmonary frailty, prior dissection or prior aortic repair that has already disrupted collaterals, connective-tissue disease that limits the durability of an endovascular seal, and the center's ability to rescue the patient if the chosen plan fails intraoperatively. The useful clinical output of the team meeting is therefore a written decision that names the intended repair route — open thoracoabdominal repair, hybrid debranching with thoracic endografting, or branched/fenestrated endovascular repair — together with the reasons the other paths were rejected, so that the next clinician to see the patient can understand both the choice and its boundary conditions.

24.2Open repair and branched/fenestrated repair are complementary options

Open thoracoabdominal repair remains a durable strategy and should not be regarded as a fallback. Contemporary cohorts at experienced centers continue to report acceptable mortality and reasonable spinal-cord, renal, and visceral outcomes in fit patients, in patients with connective-tissue disease (Marfan, Loeys-Dietz, vascular Ehlers-Danlos) in whom an endovascular seal in a fragile aorta is unlikely to remain durable, in selected post-dissection anatomy where the false lumen will need to be addressed eventually, and in cases where a stable endovascular seal or a viable branch plan cannot be engineered with current devices Contemporary outcomes open 2025 · Open Thoracoabdominal Aortic 2025 · Our experience recent 2023 · Open Treatments Thoracoabdominal 2023 · Open repair thoracoabdominal 2018. The operative plan — partial cardiopulmonary bypass or left heart bypass, distal aortic perfusion, sequential clamping, visceral patch construction, intercostal reimplantation strategy — is center-specific, but the decision to offer open repair should be made on the basis of the patient's biology and anatomy rather than on an institutional aversion to thoracotomy.

Branched and fenestrated endovascular repair has, over the past decade, become a primary option for the patient whose anatomy supports it. The decision variables are landing zones for proximal seal, branch geometry for visceral and renal target perfusion, iliac and femoral access for the large-bore delivery system, the trade-off between a custom-made device (longer manufacturing time, anatomy-specific branches) and an off-the-shelf platform (immediate availability, fixed branch configurations), and the center's procedural experience including target-vessel cannulation, branch bridging-stent management, and the management of a partially deployed device when anatomy unexpectedly resists Repair thoracoabdominal aneurysm 2025 · Early Multicentre Experience 2025 · Long-term outcomes hybrid 2024 · Branched fenestrated endovascular 2024 · Endovascular aortic arch 2023. Durability in this population is anchored to target-vessel patency and to disciplined surveillance for branch occlusion, stent fracture, or new endoleak, not to early procedural success alone.

The two approaches should be compared as complementary tools, not as a hierarchy. A fit 55-year-old with Marfan syndrome and an extent II thoracoabdominal aneurysm is usually better served by open repair; a 76-year-old with degenerative disease, suitable branch anatomy, and good iliac access is usually better served by a custom branched device. The team meeting should be willing to defend either choice on anatomic and physiologic grounds.

24.3Arch aneurysm repair uses a reconstructive ladder

Aortic arch aneurysm repair sits at the interface of cardiothoracic and vascular surgery, and the question is rarely a single modality choice — it is a position on a reconstructive ladder. The first rung is open arch replacement, usually with deep hypothermic circulatory arrest or with selective antegrade cerebral perfusion through one or both common carotid arteries, and with sequential reimplantation of the supra-aortic branches. The second rung is hybrid debranching: an extra-anatomic supra-aortic reconstruction (ascending-to-innominate-to-carotid grafting, for example) creates a clean proximal landing zone, after which a thoracic endograft excludes the diseased arch. The third rung is branched or fenestrated arch endografts, in which the device itself preserves flow into one, two, or three supra-aortic branches without an open chest Early Multicentre Experience 2025 · Long-term outcomes hybrid 2024 · Endovascular aortic arch 2023 · Management Ascending Aorta 2022 · Outcomes after endovascular 2021.

The choice between rungs is anatomic and physiologic. Open arch replacement remains the operation of choice for connective-tissue patients, for those with a frankly diseased aortic root, for those who already need an aortic valve or coronary procedure, and for those in whom the supra-aortic branch anatomy will not accept a reliable seal or a stable branch device. Hybrid repair is attractive when a patient cannot tolerate full circulatory arrest but the proximal landing for a standard endograft is unsuitable; the trade-off is that the debranching itself is not trivial and the late durability of the supra-aortic bypass becomes part of the lifetime surveillance burden. Branched endografts are attractive when the supra-aortic anatomy supports a stable seal, when the patient cannot tolerate sternotomy, and when the center has the procedural depth to handle a difficult target-vessel cannulation safely; off-the-shelf devices remain a research-into-practice area and centers should be honest with patients about emerging-technology status.

The arch decision should be owned by the combined aortic team because access, cerebral protection, and rescue options are inseparable. A vascular operator may favor a branched endograft; the cardiothoracic team may favor open repair on aortic-root grounds; the right answer is whichever path the combined team can execute and rescue at their center, with patient anatomy as the tiebreaker.

24.4Use comparative evidence to structure the decision, not to shortcut it

Systematic reviews, Cochrane comparisons, hybrid-arch reviews, and population-level studies are the evidence the team should bring into the room — not to decide the case, but to discipline the conversation. The Cochrane review of TEVAR for thoracoabdominal aneurysm TEVAR 2022, the hybrid-arch Cochrane review Hybrid repair 2021, contemporary meta-analyses, and large registry and population-level series let the team compare early mortality, spinal-cord injury, renal injury, target-vessel events, and reintervention across open, hybrid, and branched/fenestrated repair Efficacy Safety Endovascular 2024 · Systematic review contemporary 2020 · Treatment Trends Outcomes 2025 · Outcomes after endovascular 2021. The pooled signal, read with appropriate caution, is that endovascular and hybrid repair generally show lower early mortality and shorter hospital stay than open repair, while open repair shows greater durability against late reintervention; spinal cord and renal events are real for all three strategies and depend more on extent and patient physiology than on modality.

The limitation is at least as important as the headline numbers. Patients are not randomly assigned to repair type in most contemporary thoracoabdominal and arch evidence; the fittest patients with the most hostile open anatomy tend to receive endovascular repair, while open repair is often offered to younger fit patients with extensive disease. Center experience varies more in this space than in any other corner of vascular surgery, and device-generation effects are real — the modern multi-branch platforms are not the same as the early fenestrated devices reported in older series. Urgency also distorts the comparison: emergency presentations are over-represented in some open cohorts and in others are excluded entirely. The practical use of comparative evidence is therefore as a frame for the team meeting — to remind everyone of the magnitudes of early mortality, spinal-cord injury, renal injury, and reintervention they should expect, and to surface the specific outcome a given patient is most worried about — rather than as a rule for allocation.

24.5Spinal cord protection is planned before the first incision or puncture

Spinal cord injury is the complication that converts a technically successful complex aortic repair into a life-altering failure, and the time to plan protection is before the first incision or puncture, not during a postoperative deficit. The mechanism is collateral collapse: the cord is fed by intercostal, lumbar, hypogastric, and subclavian-derived collaterals, and once a long segment of intercostal arteries is covered or interrupted the cord falls onto a reduced collateral network whose perfusion pressure must be defended actively.

Protection is therefore not a single intervention but a layered system planned by the team. Preserve collateral circulation where possible: stage the coverage when anatomy allows so the collateral network can expand between procedures, protect the left subclavian and hypogastric inflow that feed the network, and avoid covering critical intercostal arteries when a more limited landing zone will do. Use cerebrospinal-fluid drainage selectively rather than routinely — drainage widens the cord-perfusion gradient and is part of the standard plan for extensive coverage, but it carries its own bleeding, neurological and catheter-related risk and a drainage decision should reflect local protocol and the specific patient's risk profile. Maintain perfusion pressure with active vasopressor and volume management during and after the procedure, and resist the temptation to allow permissive hypotension once the device is deployed. Use motor and somatosensory evoked-potential neuromonitoring where local expertise supports it, because intraoperative deficits caught early are often reversible by adjusting clamping, perfusion, or coverage strategy. Finally, have a written rescue protocol for delayed neurologic deficit so that the team — including out-of-hours staff — knows to escalate blood pressure, volume, oxygen delivery, and CSF drainage immediately rather than waiting for senior input Safety Outcome Minimally 2024 · Systematic Review Use 2019 · Use lumbar drains 2016 · Systematic review motor 2016 · Distal aortic perfusion 2012 · Cerebrospinal fluid drainage 2012 · Collateral network concept 2023 · Minimally Invasive Segmental 2022.

Exact drain targets, staging intervals, perfusion-pressure floors, and neuromonitoring alarm criteria are center protocol decisions grounded in the cited evidence that should be set in writing at the center rather than chosen ad hoc in the operating room. The published series and reviews give plausible ranges; the team should pick one set, document it, and run it consistently so that anesthesia, surgery, and critical care are working from the same numbers.