Beta-blocker therapy and aortic growth in nonsyndromic ascending thoracic aortic aneurysms: a serial CT analysis.

Abstract

Background: The role of beta blockers in slowing aneurysm progression in patients with nonsyndromic ascending thoracic aortic aneurysms (aTAA) remains uncertain. We investigated the association between beta blocker therapy and longitudinal ascending aortic growth measured by serial computed tomography (CT).

Methods: This retrospective single-center cohort study included 390 adults with nonsyndromic aTAA who underwent at least two contrast-enhanced CT examinations separated by a minimum of 2 years. Patients were classified according to beta blocker therapy (311 users and 79 nonusers). The primary outcome was the annual ascending aortic growth rate. Secondary outcomes included changes in the ascending aortic size index (ASI) and ascending aortic height index (AHI). Univariate and multivariable linear regression analyses were performed to identify independent predictors of annual aortic growth.

Results: Baseline ascending aortic diameter was comparable between beta blocker users and nonusers (45.1 ± 3.5 vs. 45.2 ± 3.6 mm, P = 0.73). During a mean CT follow-up of 73.2 ± 39.1 months, annual ascending aortic growth rates were similar between groups (0.40 ± 0.54 vs. 0.45 ± 0.65 mm/year, P = 0.49). Likewise, changes in ASI and AHI did not differ according to beta blocker therapy. In multivariable linear regression analysis, beta blocker use was not independently associated with annual ascending aortic growth (standardized β = -0.031, P = 0.548). Exploratory subgroup analyses demonstrated numerically lower annual growth rates among beta blocker users with baseline ascending aortic diameters ≥48 mm and bicuspid aortic valves; however, neither comparison reached statistical significance.

Conclusions: In this long-term CT-based cohort of patients with nonsyndromic aTAA, beta blocker therapy was not independently associated with slower ascending aortic growth or changes in indexed aortic dimensions. Larger prospective studies are needed to further clarify the role of beta blockers in limiting aneurysm progression.