Patterns of aortic remodelling after total arch replacement with frozen elephant trunk for acute aortic dissection

Abstract

OBJECTIVES We investigated the outcomes of total arch replacement with frozen elephant trunk (FET) for Stanford type A acute aortic dissection and the patterns of postoperative aortic remodelling from computed tomographic (CT) findings. METHODS From April 2015 to November 2018, we performed total arch replacement with FET for Stanford type A aortic dissection in 30 patients. Postoperative contrast-enhanced CT showed the position of the FET distal end, the number and the site of communications between the lumina and the presence or absence of aortic remodelling. RESULTS Primary entry tear was found in the ascending aorta (n = 6), proximal arch (n = 6), aortic arch (n = 11) and distal arch (n = 7). The mean diameter and length of FET were 26 ± 2 and 84 ± 18 mm, respectively. Postoperative contrast-enhanced CT was performed in 26 patients. When the number of communications between the lumina was 0, complete aortic remodelling was achieved in all cases (n = 12). In the case of the most proximal tear in the descending aorta (n = 9), aortic remodelling was not recognized in 3 cases, and additional TEVAR was performed because of diameter enlargement. In the remaining 6 patients, neither aortic remodelling nor aortic diameter enlargement was recognized. When the most proximal tear was below the diaphragm (n = 5), aortic remodelling occurred up to the most proximal tear, but not in the periphery. CONCLUSIONS We investigated the patterns of aortic remodelling after total arch replacement with FET for Stanford type A aortic dissection from postoperative CT findings. Regardless of the position of the most proximal tear in the descending aorta, aortic remodelling did not occur as long as the most proximal tear was located in the descending aorta. When the most proximal tear occurred in the descending aorta, TEVAR as a pre-emptive treatment can be effective in preventing postoperative aortic adverse events.

Hemodynamic predictors of negative false lumen remodeling after frozen elephant trunk for acute aortic dissection

“…Therefore, it is crucial to treat only those patients who are likely to develop negative FL remodeling. To date, CT-based predictors of FL enlargement or negative remodeling have been identified as the number of vessels originating from the FL [ 8 ] and re-entry locations [ 9 ]. However, morphological assessment is limited; this study identified predictive factors by functional evaluation of fluid dynamics using 4D flow MRI.…”

“…Nevertheless, this procedure may be feasible to perform in patients at risk of negative aortic remodeling, specifically the expansion of the aorta, especially in the FL region. Though several morphologic predictors based on computed tomography (CT) angiography findings have been employed to detect negative aortic remodeling [ 8 , 9 ], and to the best of our knowledge, those that can be applied for further treatment are lacking. Notably, four-dimensional flow magnetic resonance imaging (4D flow MRI) has allowed us to perform functional analysis of the predictors of negative aortic remodeling [ 10 , 11 ].…”

Extended thoracic endovascular aortic repair for residual aortic dissection after type A aortic dissection repair

“…In terms of aortic remodeling, we found that once there was a tear in the DTA on postoperative CT, aortic remodeling did not occur regardless of the levels of the descending aortic communications between the lumina. 16 In such cases, additional TEVAR is necessary to prevent any adverse aortic events in the downstream aorta. 17 In the present series, aortic remodeling occurred in the stented segment of the aorta in 83% of the patients on postoperative contrast-enhanced CT during the average follow-up of 22 months.…”

Total arch replacement in the treatment of acute type A aortic dissection

“…The main risk factor for reintervention on the arch or descending thoracic aorta after proximal aortic repair is the persistent flow in the false lumen, which is associated with aneurysmal degeneration of the dissected aorta (52,55,56). Presence of a tear in the descending aorta on post-operative scans predicts failure of the aorta to remodel (64,65) as these communications between lumina infer pressurization of the false lumen and unlikely false lumen thrombosis (66). Analysis of pre-discharge CT scans after ATAD repair demonstrate additional entry tears in the proximal descending thoracic aorta in 38% of cases, distal descending thoracic aorta in 25% and abdominal aorta in 41% of patients (67).…”

“…In cases where the primary entry tears are located in the aortic arch and/or proximal descending thoracic aorta, arch replacement with FET allows false lumen exclusion leading to false lumen thrombosis and its obliteration (61,65,68). Available long-term data suggest that aortic remodeling with partial or complete thrombosis of the persistent false lumen can be expected in approximately 90% of cases along the length of the stent graft (69)(70)(71).…”