Spinal Cord Ischemia in Open and Endovascular Aortic Repair

Abstract

Despite the improvements, spinal cord ischemia is still one of the major and most dramatic potential complications after thoracic and thoracoabdominal aortic treatments, for both open and endovascular procedures. A multimodal approach, which includes several intraoperative and postoperative maneuvers, may contribute to optimizing the spinal cord tolerance to ischemia. The aim of this article is to report the different techniques employed to improve spinal cord perfusion, directly and indirectly through collateral circulation.

Fig. 1

With preoperative computed tomography angiography, using postprocessing tools, the whole path of the arterial feeder to the spinal cord can be visualized, from the aorta to the anterior spinal artery (A: intercostal artery; B: anterior radicular artery; C: arteria radicularis magna or artery of Adamkiewicz; D: anterior spinal artery).

Fig. 2

Schematic view of left heart bypass. ( A ) A 20-Fr cannula is inserted in one of the left pulmonary veins for the arterial blood drainage. ( B ) Through a centrifugal pump, the oxygenated blood is routed into the left femoral artery for synchronous proximal (visceral and intercostal vessels) and ( C ) distal perfusion during sequential clamping, using a nonocclusive femoral cannula. ( D ) A “Y” connector provides two occlusion/perfusion catheters for selective visceral perfusion with blood.

Fig. 3

Critical intercostal arteries reattachment during thoracoabdominal aortic aneurysm open surgical repair with three different techniques. ( A ) An aortic island including the origin of several intercostal arteries is reattached to a fenestration created on the aortic graft. ( B ) Intercostal arteries are reattached selectively to the graft via 6/8-mm interposition grafts. ( C ) Another possible way to reattach critical intercostal arteries is represented by the “loop graft”; a 14/16-mm is anastomosed proximally and distally to the aortic graft. A fenestration is created in this loop graft to reattach the origin of multiple intercostal arteries (dotted circle). TAAA, thoracoabdominal aortic aneurysm.

Fig. 4

( A ) Once the dura has been punctured with the introducer needle, ( B ) a drainage catheter is inserted 8 to 10 cm along the intradural space. The catheter is then connected to a pressure transducer, and the fluid is drained to keep the pressure below 10 cm H ₂ O. ( C ) Automated systems, such as Liquoguard, are available for this purpose.

Fig. 5

( A ) Preoperative computed tomography angiography (AngioCT) is used for the identification of critical intercostal arteries. According to the preoperative spinal cord (SC) vasculature imaging, the occlusion of SC feeders may be planned to induce a collateral network preconditioning. ( B ) With the aid of intraoperative adjuncts, such as the fusion technique, an easier identification of the intercostal arteries is possible during the endovascular procedure. With this imaging tool, the preoperative AngioCT is matched with the intraoperative angiography, with the possibility to underline the aortic contour and preoperatively selected vessels, such as the intercostal arteries (*). This approach allows an easier identification of the intercostal vessels for catheterization. ( C ) Embolization with coils may be performed to selectively occlude the intercostal artery.