Spinal Cord Ischemia Following Thoracoabdominal Aortic Aneurysm Repair: Translational Insights from Stroke and Traumatic Injury for Biomarker Development

Background: Spinal cord ischemia (SCI) is a severe complication of thoracoabdominal aortic aneurysm (TAAA) repair, associated with substantial morbidity and mortality. Despite advances in operative techniques, its pathophysiology remains incompletely understood, with no reliable biomarkers available for early detection or risk stratification. Methods: This narrative review synthesizes current evidence on the pathophysiology of SCI following aortic intervention, integrating insights from ischemic stroke and traumatic spinal cord injury to identify key mechanistic pathways and potential biomarker targets. Results: SCI results from multifactorial impairment of spinal cord perfusion pressure (SCPP) driven by extensive aortic coverage, disruption of segmental arterial inflow, hypotension, and impaired collateral circulation. While acute hypoperfusion initiates injury, secondary processes—including excitotoxicity, oxidative stress, and neuroinflammation—drive progression. Cytokine signaling and immune activation contribute to blood–spinal cord barrier disruption and vasogenic edema, with Aquaporin-4 playing a central role in delayed injury. Candidate biomarkers, including neuron-specific enolase, S100β, and glial fibrillary acidic protein, reflect neuronal damage but lack sufficient sensitivity and temporal resolution for clinical use. Emerging evidence supports a multimodal biomarker approach incorporating inflammatory, structural, and Aquaporin-4-dependent edema-related pathways. Conclusions: Spinal cord ischemia following thoracoabdominal aortic aneurysm repair is a dynamic and multifactorial process in which reduced spinal cord perfusion pressure represents a final common pathway linking diverse perioperative factors to ischemic injury. Secondary mechanisms, particularly neuroinflammation and Aquaporin-4-driven vasogenic edema, play a central role in injury propagation and represent promising targets for biomarker development. Future strategies should focus on longitudinal, multimodal biomarker approaches to improve early detection, risk stratification, and therapeutic intervention.