Strategies to improve outcomes for acute type A aortic dissection with cerebral malperfusion

Abstract

OBJECTIVES We aimed to identify predictors of postoperative permanent neurological deficits (PNDs) and evaluate the early management of cerebral perfusion in patients undergoing surgical repair of acute type A aortic dissection with cerebral malperfusion. METHODS Between October 2009 and September 2018, a total of 197 patients with acute type A aortic dissection underwent aortic replacement. Of these, 42 (21.3%) patients had an imaging cerebral malperfusion (ICM). ICM was assessed preoperatively, which also revealed whether dissected supra-aortic branch vessels were occluded or narrowed by a thrombosed false lumen. After September 2017, early reperfusion and extra-anatomic revascularization were performed in cases with ICM. RESULTS Hospital mortality rates for cases with ICM were 4.8% (2/42). Before September 2017, PND were observed in 6 patients (54.5%) with preoperative neurological symptoms (n = 11), and 7 patients (33.3%) without neurological symptoms (n = 21) in patients with ICM. Occlusion or severe stenosis of supra-aortic branch vessels (odds ratio, 7.66; P < 0.001), regardless of preoperative clinical neurological symptoms, was a risk factor for PND. After September 2017, 7 of 10 patients with ICM underwent early reperfusion and extra-anatomic revascularization. PND did not occur in any of these 7 patients. CONCLUSIONS Occlusion or severe stenosis of supra-aortic branch vessels is a predictor of PND risk in patients undergoing surgery for acute type A aortic dissection. Early reperfusion and extra-anatomic revascularization may reduce the risk of neurological complications in patients with ICM, with or without neurological symptoms.

Impact of direct carotid artery perfusion in acute type A aortic dissection involving the common carotid artery

“…Furukawa et al reported that patients with partial or complete thrombosis of the arch vessels are at a high risk of cerebral malperfusion, especially when the false lumen of the innominate artery is occluded [9]. Gomibuchi et al stated that postoperative neurological deficiency is caused not only by disturbed blood flow in an occluded or stenotic carotid artery but also by a thromboembolism owing to thrombi derived from a thrombosed false lumen [6]. Gaul et al reported that in one-third of all patients with preoperative stroke, ischemic stroke was not caused by an extension of the dissection toward the supra-aortic vessels.…”

“…Once SCP is established, thrombi in the false lumen may enter the true lumen through a small entry. If re-entry occurrs at the distal site and we anastomose at the orifice of the brachiocephalic artery, it is possibile that the thrombi are transferred from the false lumen via the distal re-entry site [6].…”

“…Previous reports have proposed that central repair of entry closure and true lumen reinstallation should be performed first to improve early survival rate and neurological outcomes; however, some patients have developed irreversible neurological deficits after central aortic repair [3,4]. Moreover, it is difficult to determine which patients with neurological symptoms will recover after surgery [5,6]. Therefore, Gomibuchi et al introduced concept of "imaging cerebral malperfusion" for subclinical patients, which is defined as having occlusion or narrowing of common carotid artery in a preoperative computed tomography regardless of symptoms [6].…”

“…Moreover, it is difficult to determine which patients with neurological symptoms will recover after surgery [5,6]. Therefore, Gomibuchi et al introduced concept of "imaging cerebral malperfusion" for subclinical patients, which is defined as having occlusion or narrowing of common carotid artery in a preoperative computed tomography regardless of symptoms [6].…”

“…It is often multifactorial, frequently coexisting with circulatory collapse, sequelae of acute hypoxia, and thromboembolism originating from the false lumen [7]. However, as a main cause of postoperative neurological deficiency, the possibility of thromboembolism owing to thrombi derived from a thrombosed false lumen has been noted [6,[8][9][10]. According to these reports, the removal of thrombi from the false lumen before the initiation of selective cerebral perfusion (SCP) is extremely important.…”