Abstract 14527: Determinants of 3D Principal Strain, 3D Circumferential, 3D Longitudinal, and 3D Radial Strains
Background: 3D myocardial strain by speckle tracking echocardiography is thought to be more sensitive than EF in the detection of LV myocardial dysfunction. We compared 3D principal (P), circumferential (C), longitudinal (L) and radial (R) strains to hemodynamics and LV structure and function indices obtained by cardiac magnetic resonance (CMR).
Methods: Subjects were prospectively recruited and underwent CMR and 3DECHO within 2 hours. 3D principal strain (P) was the 3D vector from which C, L, and R strain components are derived. Age, heart rate (HR), mean blood pressure (MBP), CMR LV volumes (EDV, ESV), EF, and CMR derived end-diastolic pressure (EDP) were correlated with each strain index by Pearson's correlation. A Trend test was used to compare the variables across the subgroups.
Results: 120 subjects (62% male) were analyzed. Of those, 68 were normal (Gp1), 15 had heart failure with preserved LVEF (Gp2) and 37 had heart failure with LV dysfunction (Gp3). Comparing Gps 1, 2 and 3, there were significant differences in LVESV (57, 64, and 125 ml, p<0.001), and in LVEF (59%, 60%, 39%, p<0.001). Larger LV volumes and lower LVEF were associated with lower 3D strain indices (all p values <0.001). Of the strain indices, the 3D P strain had the strongest association with LV volume and LVEF with values of -35%, -33% and -26% (p<0.001) in Gps 1, 2 and 3, respectively. Age and BSA were only modestly associated with 3D strain parameters while HR and MBP were not. The table below shows the mean values for each parameter, the Pearson's correlation coefficient, and the p values.
Conclusions: 1) No significant correlation was noted with HR or MBP, while weaker associations were noted with age, BSA and EDP. 2) 3D P, C, L and R strains are capable of discriminating between normals, heart failure patients with systolic dysfunction and heart failure patients with preserved LVEF. 3) 3D P strain shows the strongest correlation with CMR ESV and CMR EF and may be a particularly useful index of myocardial performance.
- © 2011 by American Heart Association, Inc.