False Lumen Thrombosis and Aortic Diameter Changes in 6 Segments of Aorta Following TEVAR Procedure for Acute Complicated Type B Aortic Dissection

Abstract

Introduction: Thoracic endovascular aortic repair (TEVAR) has proved its role in obliterating primary intima tear, increasing true lumen(TL)/false lumen (FL) ratio, depressurizing or enhancing thrombosis of FL and therefore preventing FL rupture for acute complicated type B aortic dissection (cTBAD). [1,2] However, persistently patent false lumen due to endoleaks surrounding aortic stent grafts (ASG), stent-induced new entry (SINE) and reentry of distal aorta is not uncommon. Enlargement of lower thoracic and upper abdominal aorta could follow. [2] Deteriorating blood flow of FL-perfused branch vessels(FPBV) is also a concern after TEVAR. [4] Methods: From Jan. 2015 to Jul. 2018, all cTBAD undergoing TEVAR procedures were retrospectively reviewed. Atypical TBAD including traumatic aortic injury and intramural hematoma was excluded. Series of follow-up computed tomography (CT) were meticulously reviewed to define classification of FL thrombosis, change of FL/TL ratio, aortic diameter change in 6 segments of aorta. The associated morbidity, including FPBV, mortality and re-intervention were also traced. Results: Total 42 patients, aged 24 to 86(mean55), 36 males and 6 females received TEVAR procedures for cTBAD in mean 20.2 hours from visit to operation room. Patients were discharged on postoperative day 2-120(mean 13). There were 9.5% 30-day mortality and 2.4% late mortality. 16.7% early complications included ischemic bowel, limb weakness, retrograde dissection, stroke and AKI etc. 26.2% late complications included chronic respiratory failure, pSINE, dSINE, renal infarction, chimney graft occlusion etc. Comparing to the pre-operative sizes, diameter of upper thoracic aorta and lower thoracic aorta showed no statistically significant change in the 3-year follow-up CT series. 100% and 56.7% patient's diameter of middle thoracic aorta increased in the 15 days(D)(p=0.03) and 3 months(M)(p=0.03) respectively after operation. 50% patient's diameter of upper abdominal aorta significantly started increasing during 15D to 3M after operation(p< 0.01). Middle abdominal aorta and lower abdominal aorta started increasing during 3M to 9M(p< 0.01) and 9M to 24M(p< 0.01) after operation. The FL/TL ratio in lower thoracic aorta was decreased and zero in 42.1% and 39.5% patients respectively. The FL/TL ratio in upper abdominal aorta was increased and zero in 36.8% and 23.7% patients respectively. Extent of false lumen thrombosis was 5.3% with retrograde type A aortic dissection, 23.7% with thrombosis above the stent graft, 73.8% with thrombosis throughout thoracic aorta and 10.5% complete thrombosis throughout native aorta. Conclusion: cTBADs have been managed by TEVAR with relatively high mortality and morbidity in our center due to questionable decision-making and loss of branch vessel revasculization. The morphology of aortic remodeling was disclosed with enlarging middle thoracic aorta initially and then enlargement of upper and middle abdominal aorta. Besides, the FL thrombosis is satisfying.[Survival and Freedom from Re-intervention in TEVAR for cTBAD]View Large Image Figure ViewerDownload Hi-res image Download (PPT) Disclosure: Nothing to disclose