Neurological injury
Neurological injury is a common and well-documented complication associated with aortic arch repair. Spinal cord ischaemia (SCI) can occur in up to 7.3% of cases, while cerebrovascular accidents occur in up to 15.9% of cases.5 A meta-analysis by Bashiret al. reports a pooled estimate of incidence of 7% and 3.5% for CVA and paraplegia respectively.1 Intriguingly, Yamamoto and colleagues reported no cases of SCI or CVA following Z-0-FET, while the single mortality in Jakob and colleagues’ report was attributed to cerebrovascular insufficiency.16, 1750% (n=3) patients experienced early postoperative cerebral malperfusion, however none were left with lasting neurological deficit.17 In contrast, Beckmann and colleagues reported a 21% (n=20) and 26% (n=25) incidence of new-onset stroke and delirium following Z-2-FET respectively, while Tsagakis et al.noted 4% (n=8) of patients suffered permanent ischaemic stroke following Z-2-FET.12, 22 This discrepancy may be due, in part, to proximalisation of the stent graft. Leontyev et al.identify distal landing zones as a major risk factor for SCI, and indeed Jiang et al. notes that decreased occlusion of the intercostal vessels in Z-0-FET may protect against SCI.18, 26Rezaei et al. also highlight the use of FET stents longer than 15 cm, or extending beyond T8, as risk factors for SCI , and that stent length less than 10 cm may decrease the risk of SCI.1Jiang et al. further recommends performing FET arch repair with visceral perfusion at moderate hypothermia (28ºC) to reduce overall HCA duration and attenuate risk of SCI.18 Additionally, Yamamoto and colleagues suggest that selective LSA perfusion could improve intraoperative spinal cord perfusion via collateral vasculature during HCA.16 These factors, in combination with the fact that the Z-0-FET approach involves reduced overall HCA, CPB, and ACP duration, suggest that proximalisation of FET repair may indeed reduce incidence of iatrogenic neurological injury.