Abstract 17989: Evolution of At-risk Aortic Tissue in Patients With Bicuspid Aortic Valve After Valve or Aorta Replacement
Objectives: Bicuspid aortic valve (BAV) is associated with increased risk of aortopathy requiring surgery. However, to date, there is no clear consensus on aortic resection extent. Our objective was to study in BAV patients the evolution of ascending aortic (AA) ‘at-risk’ tissue, as defined by elevated wall shear stress (WSS) estimated using 4D flow MRI acquired at baseline and follow up.
Methods: Eighteen BAV patients (49±15yrs) were included who underwent AA repair and MRI before surgery and at follow up (mean duration: 154±250 [7-977] days). For each patient and exam, 3D aortic systolic WSS was estimated from 4D flow MRI and at-risk tissue area was defined as the treatable region with high WSS, when compared to an atlas of physiologically normal values (as previously established in healthy controls).
Results: The baseline sinus of Valsava and mid-AA diameters were both 4.5±0.6cm. Eight patients had severe aortic stenosis or regurgitation. Three patients had aortic valve replacement without aortic resection, 8 had AA repair without hemiarch repair, and 7 had AA and hemiarch repair. In the 8 AA repair patients, 3D area of elevated WSS increased at baseline from 25±29% to 52±37% at follow up, when expressed in percentage of the AA tissue remaining after surgery up from graft to the first branch (Figure). Little change in at-risk tissue area was observed in hemiarch repair patients.
Conclusions: Our preliminary study demonstrates feasibility of 4D flow MRI to provide data regarding at-risk aortic tissue progression in BAV patients who underwent AA repair. Larger studies in a variety of clinical conditions are warranted to further understand the implications of these findings.
Author Disclosures: E. Bollache: None. P.W. Fedak: None. P. van Ooij: None. D. Guzzardi: None. S. Malaisrie: None. P.M. McCarthy: None. J. Carr: None. J. Collins: None. M. Markl: None. A.J. Barker: None.
- © 2015 by American Heart Association, Inc.