Malperfusions in Acute Type B Aortic Dissection-Predictors of Outcomes

Acute type B aortic dissection (AoD) with malperfusion is a rare and complex disease. In this specific setting, invasive treatment is generally required to improve aortic branch vessel flow. Thoracic aorta stent grafting (TEVAR) of the proximal descending thoracic aorta to cover/exclude the proximal intimal entry tear would promote resolution of the dynamic component (the most prevalent) of the malperfusion conflict by redirecting the flow within the true lumen. The aim was to study outcomes of patients undergoing TEVAR for acute (<14 days) type B AoD complicated with malperfusion and to depict any preoperative and intraoperative predictors that could affect the prognosis of those patients.

From March 2005 to January 2016, all patients treated with TEVAR for acute type B AoD with malperfusion in 2 European high-volume aortic centers were retrospectively studied. Preoperative, intraoperative, and postoperative details were collected. Preoperative computed tomography angiogram was reanalyzed on a dedicated 3D workstation (Aquarius iNtuition Viewer, TeraRecon). Thirty-day malperfusion-related complication and mortality rates were determined. Logistic regression model was used to assess preoperative and intraoperative factors affecting postoperative outcomes; in particular, details on the mechanisms of malperfusion and organ(s) involved were entered into the model and tested.

A total of 41 patients (60 years old [interquartile range (IQR): 51-68.5]; 78% men) have been included in the analysis. Patients were mostly (68.3%) affected by only 1 malperfusion syndrome, with renal ischemia being the most frequent (53.6%). The median length of aortic coverage was 197 mm (IQR: 157-209). Additional visceral/renal/iliac stentings were performed after stent graft implantation for 25 branches in 17 patients (41%). The 30-day mortality rate was 17.1%. All but 2 early deaths were related to malperfusion. The number of malperfusion syndromes was the only independent factor associated to increasing 30-day malperfusion-related complications or deaths (3 vs 1, HR = 30.3 [P = 0.001]; 3 vs 2, HR = 9.9 [P = 0.004]).

Prognosis of patients with acute type B AoD complicated initially with malperfusion syndrome(s) is severe, especially if several territories are ischemic. Early identification of those complications can be lifesaving but still lacks hard criteria.