PC020 The Role of Ascending Aortic Size in Outcomes of Patients With Uncomplicated Acute Type B Aortic Dissection

Abstract

Recent studies have shown that patients with uncomplicated acute type B aortic dissection (uATBAD) who have enlarged descending thoracic aortic diameters are at high risk of developing complications. This study aimed to determine the effect of maximum ascending aortic diameter and area on outcomes in patients with uATBAD. All patients admitted with uATBAD from June 2000 to January 2015 were reviewed, and those with available imaging were included. All measurements were obtained by a specialized cardiovascular radiologist. The maximum ascending aortic diameter and area were measured. Outcomes, including the need for intervention and mortality, were tracked over time. Data were analyzed by stratified Kaplan-Meier and multiple Cox regression analysis using SAS 9.4 software. During the study period, 304 patients with uATBAD were admitted, with 245 having noncontrast computed tomography and 131 having computed tomography angiography imaging and adequate follow-up available for analysis. The cohort had an average age of 60.9 years (60% male, 53% Caucasian). Ascending aortic area >12.1 cm2 was highly associated with subsequent arch/proximal progression (P < .0006). Ascending diameter >40.8 mm predicted lower intervention-free survival (P = .01). Ascending aortic area >12.1 cm2 predicted lower intervention-free survival (P = .005). Maximum aortic diameter along the length of the aorta >44 mm persisted as a risk factor for mortality (hazard ratio [HR], 7.34; P = .0008) after adjustment for diabetes mellitus (6.4; P = .0008), age (1.06/year; P = .0006), history of stroke (HR, 5.03; P = .0081), syncope on admission (21.11; P = .007), and ascending diameter >40.8 mm (1.09; P = .85). Max ascending aortic diameter failed to predict overall survival when two groups were compared >40.8 and < 40.8 (P = .12). However maximum aortic diameter along the length of the aorta >44 mm held true as previously demonstrated (P = .0009). Maximum aortic diameter along the length of the aorta >44 mm persisted as a risk factor for decreased intervention-free survival (hazard ratio, 3.142; P = .0038), syncope on admission (26.3; P = .004), pleural effusion on admission (3.02; P = .0008), and ascending diameter >40.8 mm (2.01; P = .04). uATBAD patients with ascending aortic area >12.1 cm2 are at high risk of developing subsequent arch/proximal progression and may require closer follow-up or earlier intervention. Ascending aortic size (diameter and area) is predictive of decreased intervention free survival in patients with uATBAD.