Aortic Remodeling After Endovascular Repair of Complicated Acute Type B Aortic Dissection

Thoracic endovascular aortic repair (TEVAR) is the optimal therapy for complicated acute type B aortic dissection (aTBAD). This study examined clinical outcomes and aortic remodeling parameters after TEVAR for patients with complicated aTBAD.

From January 2012 to December 2015, 51 patients underwent TEVAR for complicated aTBAD. Preoperative and postoperative imaging studies were analyzed for sizes of the true lumen (TL) and false lumen (FL) and for the FL thrombosis status at five locations in the thoracic and abdominal aorta.

In-hospital and 1-year mortality rates were 3.9% and 5.8%, respectively. The incidence of stroke and paraparesis were 3.9% and 5.8%, respectively. In DeBakey 3a patients, TEVAR resulted in complete FL thrombosis and/or obliteration in 73% of patients. In DeBakey 3b patients, TEVAR resulted in complete FL thrombosis and/or obliteration in 100% of patients in the proximal descending thoracic aorta and 78% in the midpoint of the descending thoracic aorta. The infrarenal FL remained patent in 78% of patients. TEVAR stabilized the size of the proximal descending thoracic aorta (pre-TEVAR 43 ± 9 mm vs post-TEVAR 39 ± 7 mm; p = 0.07). However, significant aortic expansion was observed in all other downstream aortic segments. TEVAR resulted in a significant expansion in the TL volume (pre-TEVAR 99 ± 51 cm³ vs post-TEVAR 185 ± 70 cm³; p < 0.01) and total aortic volume (pre-TEVAR 314 ± 97 cm³ vs post-TEVAR 391 ± 120 cm³; p = 0.02) while inhibiting expansion of FL volume (pre-TEVAR 215 ± 67 cm³ vs post-TEVAR 204 ± 79 cm³; p = 0.91).

TEVAR for complicated aTBAD results in low 30-day and 1-year mortality rates, with higher reintervention rates than observed with open operations. TEVAR is effective in thrombosing and stabilizing the size of the thoracic FL. The abdominal aortic FL remains patent and must be carefully scrutinized for long-term aneurysm formation.