Abstract 14906: Is Left Ventricular Area Strain obtained by Three-dimensional Ultrasound Speckle Tracking Imaging Useful in Assessing the Magnitudes of Inertia Force of Late Systolic Aortic Flow and Left Ventricular Elastic Recoil?
Background: The inertia force (IF) of the blood flowing out of left ventricle at late systole augments left ventricular (LV) elastic recoil. Preserved LV apical wall motion is substantial to give IF to the aortic flow. A novel 3-dimensional ultrasound speckle tracking imaging (3D-STI) enables us to assess LV local endocardial surface area deformation, which is named area strain. We investigated the relationship between the area strain, especially in the apical region, and the IF.
Methods: Study subjects were consecutive 35 patients with sinus rhythm who underwent diagnostic cardiac catheterization and 3D-STI (Artida, Toshiba). Seven of them were diagnosed as prior myocardial infarction and 2 were as dilated cardiomyopathy. The remaining 26 patients had no localized LV wall motion abnormality. The temporal change in area strain was calculated using commercially available software, Ultra-Extend (Toshiba). The peak area strain at end-systole was obtained in the global left ventricle and in the apical region. LV pressure was obtained using a catheter-tipped micromanometer and first derivative of LV pressure (dP/dt) was computed. Peak negative dP/dt is known not only as an index of LV relaxation but also as an index of LV elastic recoil. From LV pressure-dP/dt relationships (phase loop), IF was determined.
Results: The peak area strain in global left ventricle had significant correlations with both the peak negative dP/dt (r=-0.64, p<0.0001) and the IF (r=-0.54, p<0.001).The peak area strain in the apical region, furthermore, had much closer correlations with both the peak negative dP/dt (r=-0.73, p<0.0001) and the IF (r=-0.72, p<0.0001).
Conclusion: These findings indicate that the magnitudes of LV elastic recoil could be noninvasively estimated by the peak area strain at end-systole obtained using 3D-STI. In addition, LV apical wall deformation at end-systole has a strong impact on the formation of LV elastic recoil.
- © 2011 by American Heart Association, Inc.