Abstract 14136: Aortic Annulus Dimension Assessment by Computed Tomography for Transcatheter Aortic Valve Implantation - Differences Between Diastole and Systole
Background: Accurate assessment of aortic annular dimensions is critical for successful transcatheter aortic valve implantation (TAVI). Annular dimensions are conventionally measured at end-diastole using computed tomography (CT), but at end-systole using echocardiography and aortography. Recent studies have demonstrated significant differences in aortic annular dimensions between systole and diastole in healthy subjects. We investigated whether annular dimensions varied between systole and diastole in patients with severe aortic stenosis (AS) in whom aortic compliance may be substantially reduced.
Methods: Patients with severe AS referred for TAVI were evaluated by 128-slice multidetector-row CT (MDCT). Aortic annulus dimensions were measured at end-diastole (70-75% RR-interval) and end-systole (30-40% RR-interval). Aortic annular diameters were measured in the modified coronal view, sagittal view, and basal ring plane (maximal, minimal and mean). Differences between systole and diastole were analysed by paired t-test.
Results: Seventy-five patients were included in the analysis, 39 male (51%), mean age 82.4 ± 6.7 years. Four of the five annular dimensions measured showed a significant difference between systole and diastole, as shown in Table 1. Systolic diameter was usually larger than diastolic diameter. However, the magnitude of the difference was small with the mean difference between systole and diastole ranging from 0.15-0.82 mm.
Conclusion: There is a small magnitude but statistically significant difference in aortic annulus dimensions of patients with severe AS referred for TAVI when measured in diastole and systole. This small difference is unlikely to alter clinical decisions regarding prosthesis size or suitability for TAVI, but standardizing measurements between imaging modalities may be worthwhile.
- © 2011 by American Heart Association, Inc.