Visceral malperfusion after Frozen Elephant Trunk in chronic aortic dissection: post-operative predictors and outcomes.

Background: The aims of this study were to analyse the incidence of visceral malperfusion syndrome (MPS) following Frozen Elephant trunk operations in patients affected by chronic aortic dissection and the associated risk factors.

Methods: Between January 2007 and February 2019, 165 patients underwent surgery with FET for chronic aortic dissection. Post-operative computer tomography angiogram parameters (diameters, early post-operative false lumen enhancement and involving of aortic branches by the dissection) were collected and analysed to evaluate their impact on the occurrence of visceral malperfusion.

Results: Visceral (renal and mesenteric) MPS (with both clinical and radiological signs of MPS) was detected in 10 cases (6.1%). Post-operative visceral malperfusion was strongly related with in hospital mortality. The involvement of the visceral branches in the dissection was not a risk factor for visceral malperfusion occurrence, while a larger post-operative total aortic diameter at level of the coeliac trunk increased the risk of visceral MPS (OR 1.05; CI 1.002-1.102, p-value = 0.04). Furthermore, visceral MPS was associated to a complete thrombosis of the false lumen at level of the distal descending thoracic aorta.

Conclusions: The development of post-operative MPS in frozen elephant trunk is strongly related to in-hospital mortality. The involvement of aortic branches by the dissection does not represent a real predictive risk factor for MPS, while early larger aortic diameters and false lumen thrombosis represent independent risk factors for MPS and in-hospital mortality.