Follow-up Study Of Type-A Aortic Dissection After Surgical Treatment And Aortic Dissection Undergoing The Stented Elephant Trunk Procedure

Objective:(1) To clarify if our surgical strategy according to further subdivision is justified for patients with type-A aortic dissection (AAD). (2) To assess the outcome of stented elephant trunk (SET) surgical approach for aortic dissection in Marfan and non-Marfan patients. (3) To assess the influence of anticoagulation treatment on the evolvement of residual false lumen after SET procedure with mechanical prosthetic valve replacement for aortic dissection patient.Methods:(1) AAD patients of 834 from 1997 to 2008 were further divided into subgroups according to the pathology of aortic root, aortic arch and descending aorta. Supra-commissural replacement of the ascending aorta was applied to 517 patients, two hundred and eighty-six patients received a composite replacement, one hundred and eight patients were treated with the aorta valve-sparing technique, hemi or total arch replacement was performed in 720 patients with 316 patients undergoing the concomitant conventional or SET procedure, and fifteen patients were accomplished with total aortic replacement.(2) Between 2003 and 2008, twenty-four patients were made definite diagnosis of Marfan among eighty-three aortic dissection patients undergoing the total arch replacement and SET procedure. All the patients were not accompanied with other clear systematic diseases. Twenty-three patients received aortic root procedure combined with aortic valve replacement.(3) Between 2003 and 2008, one hundred and eighty-one aortic dissection patients undergoing the open SET procedure concomitant with arch and/or proximal surgery were enrolled in this study. Fifty-five patients received an aortic valve replacement (AVR) with mechanical prosthesis. According to whether mechanical valve was implanted (namely long-term anticoagulation was necessary or not), patients were divided into two groups with and without AVR.The aorta was measured using enhanced computed tomography (CT), and the diameter ratios between the true lumen and aorta were calculated and the thrombosis extent of false lumen was quantified.Results:(1) Overall hospital mortality was 3.24%(27) and severe morbidity excluding rethoractomy for bleeding was 6.9%. Survival was>90%in all subtypes to the last date of visit. Two patients required reoperation for failure of the reconstructed valve and nineteen patients needed aortic reoperation. Follow-up CT study of 201 (67.7%) patients undergoing the stented elephant trunk procedure showed significant difference in the diameter ratios of the stent and the aorta at the carina level at different periods.(2) Follow-up CT study over one year postoperative showed no difference about the diameter ratios of stent and aorta at the same level between groups (Marfan 0.78±0.21 versus non-Marfan 0.87±0.24,p=0.336, at the coryna level). The residual false lumen in the distal descending aorta remained patent in 33.3%of Marfan and 30.5%of non-Marfan. Hospital and late mortality at follow-up time did not show significant differences between groups (4.2%versus 1.7%,p=0.506; 8.3%versus 8.5%,p=0.983). Survival at four years was no significantly different with 85.2+10.7%for Marfan, and 89.6+5.2%for non-Marfan (p-0341). Four patients from Marfan and two patients in non-Marfan required reoperation for distal dissection or aneurysm (16.7% versus 3.4%;p=0.055).(3) Follow-up CT study at one year showed significant difference between groups, mainly in the diameter ratios of the stent and aorta at the same level (p=0.005, at the carina; p=0.003, at the stent end). Accordingly CT data after discharge were significantly different in the extent of false lumen thrombosis at the carina (p=0.018, at 3-6 months;p=0.020, at one year). Over one year after surgery, the residual false lumen around the stent graft achieved complete thrombosis in 87.3%of patients with AVR and 98.4%without AVR (p=0.005). One patient with AVR and three patients without AVR required re-operation on the descending aorta.Conclusions:This subtype classification is useful in determining the indication and optimal surgical strategy for AAD. The SET technique is an effective way of closing the false lumen in proximal descending aorta and might contribute to the comparable and favorable long-term outcome for aortic dissection in Marfan and non-Marfan patients. Valve-related anticoagulation can slow down the remodeling of proximal descending aorta of aortic dissection after SET implantation.