Abstract 721: Vascular Assessment - New Application for Velocity Vector Imaging
Background: Velocity vector imaging (VVI) is a novel 2-D speckle-based technique to evaluate tissue deformation. We studied the feasibility of VVI to assess aortic strain, distensibility and stiffness in aortic valve disease.
Method: We examined 85 patients (66±11 years) with aortic stenosis (AS) or aortic regurgitation (AR) by transesophageal echocardiography (TEE) in the operating room prior to surgery. The 2-D short-axis loops and M-mode of descending aorta were acquired and radial artery pressure noted. TEE images were analysed off-line by VVI software, Figure⇓.
Results: Patients with AR had higher strain and distensibility, Table 1⇓. Compared to AS, AR had higher VVI dA/dt, 7.5±3.5 vs 3.1±1.0 (cm2/s, p<.0001), and dA/dt correlated to fractional area (r=0.97, p<.0001), but not to diastolic aortic area. VVI and M-mode correlated for strain (r=.91, p<.0001), distensibility (r=.83, p<.0001) and stiffness (r=.78, p<.0001). Inter- and intra-observer variability for the VVI variables were, in terms of CV, 1.9–9.5%.
Conclusion: VVI is a feasible method for the assessment of the elastic properties of descending aorta with highly acceptable variability and VVI derived strain, distensibilty and stiffness strongly related to the corresponding M-mode derived parameters. VVI has the advantage to incorporate the aortic circumference, consequently accounting for local variations.