Abstract 18456: Morphologic Predictors of Aortic Growth in Conservatively Treated Type B Aortic Dissection

Abstract

Purpose: Conservative management of acute type B aortic dissection (ABAD) is often associated with aortic enlargement during follow-up, increasing the risk of aortic rupture. The goal of this study was to investigate whether morphologic characteristics of the dissection can predict annual aortic growth.

Methods: All conservatively managed type B dissection patients of four referral centers were included (2000-2010). Aortic diameters were measured at 5 levels on the baseline and last follow-up CTA, and annual aortic growth rates were calculated for all segments. Linear regression was used to study the influence of aortic morphologic characteristics on aortic enlargement.

Results: Sixty-two patients were included (41 male; mean age 60.3 ± 10.7 years). Among the 310 analyzed segments, 248 (80.0%) were dissected of which 211 (85.1%) showed aortic growth. Overall, the mean diameter increased from 36.1 ± 9.4 mm to 40.2± 11.1mm (p < 0.001) corresponding with a mean aortic growth of 3.1 ± 6.3 mm/year. Multivariate linear regression analysis showed male gender (95% CI 0.84 - 4.27; p = .004), detection of entry tears (95% CI 0.32 - 8.01; p = .034,) and a saccular false lumen (95% CI 1.50 - 7.28: p = .003) were associated with a significantly increased aortic growth rate. Increasing age (95% CI -0.24 - -0.5; p = .003), false lumen located on the convexity (95% CI -4.56- -0.64; p = .009) and a circular configuration of the true lumen (95% CI -5.04 - -0.02; p = .048) were associated with a decreased aortic growth rate.

Conclusions:Age, gender, saccular false lumen, detection of entry tears, the presence of the entry tear in the oncavity of and configuration of the true lumen, appear to affect aortic growth rates in conservatively treated ABAD patients. Assessment of these characteristics may be useful in the selection of ABAD patients who might benefit from closer radiologic surveillance or early intervention.