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Monaco et al. Vessel Plus 2023;7:23 https://dx.doi.org/10.20517/2574-1209.2023.113 Page 3 of 14

Figure 1. The multimodal approach for SCI prevention is based on MAP, CVP and CSFP modulation. MAP: Mean arterial pressure; CVP:
central venous pressure; CSFP: cerebrospinal fluid pressure.

PATHOPHYSIOLOGY OF SPINAL CORD ISCHEMIA
Risk factors associated with spinal cord ischemia
A greater understanding of the anatomy and physiology of spinal cord perfusion has led to the recognition
of several risk factors associated with spinal cord ischemia (SCI). The extent of aortic replacement is the
most important predictor, with the highest rates observed for Extent II (10%-20% and Extent I TAAAs and
[7-9]
the lowest rates for Extent IV TAAAs (1%-5%)) . In addition, occlusion of the collateral network
(hypogastric and/or vertebral artery) is associated with a higher rate of immediate paraplegia and a lack of
[10]
improvement in motor function following remedial maneuvers . Other determinants include prior aortic
replacement, chronic kidney disease, chronic obstructive pulmonary disease, and age [10,11] .

Spinal cord collateral network
The artery of Adamkiewicz is a significant branch of a segmental artery (SA) found in the lower thoracic or
upper lumbar region, originating from T8-L1. It possesses a distinct hairpin turn and plays a crucial role in
supplying blood to the anterior spinal artery (ASA). In the treatment of extensive TAAAs, careful
identification and subsequent reimplantation of the SA have been considered the most effective strategy to
prevent severe neurological complications. However, the experience gained in endovascular treatment of
TAAAs has shown that SCI is a potentially avoidable outcome, even when there is a significant sacrifice of
the segmental arteries. This has led to a shift from the traditional anatomical paradigm, where the absence
of blood flow was considered synonymous with SCI, to a pathophysiological approach. As a consequence,
the need for a comprehensive understanding of spinal cord circulation is often overlooked, and the focus
shifted to hemodynamic and metabolic variables as the main determinants of SCI prevention. In this
approach, factors related to blood flow dynamics, such as blood pressure optimization and collateral vessel
recruitment, as well as metabolic factors affecting spinal cord tissue oxygenation and energy supply, are
considered crucial for preventing SCI. Lazorthes et al. detailed the multiple vessels that contributed to the
[12]
spinal cord blood supply and first implemented Adamkiewicz’s original anatomical observations . They