Abstract 21543: Prediction of Left Atrial Global Strain and Strain Rates During Atrial Contraction and Relaxation in Healthy Individuals
Background: Strain and strain rate imaging of the left atrium (LA) allows detailed assessment of atrial myocardial contractility and relaxation. In this study, we are reporting the global strain and strain rates of the left atrium in 100 normal individuals, and tested whether the prediction of these global indices can be accomplished through analyzing only selected LA segments.
Methods: We invited healthy individuals without a prior history or evidence of any cardiovascular disease or risk factors to participate. The 2D speckle tracking longitudinal peak strain and strain rates during atrial contraction, and atrial relaxation were obtained through averaging the values from 13 LA segments. We assessed whether these global scores can be predicted from assessment of only selected segments using a forward stepwise regression. We identified which of the permutations with various numbers of segments provided the best prediction of the global score.
Results: A total of 100 consecutively enrolled persons from 2 sites (Mayo Clinic Rochester and University of British Columbia Vancouver General Hospital (48 men, 52 women, mean age 45 ± 11 years) were included in the analyses. The table shows the global strain and strain rate values for 13 segments (total global) during atrial contraction and atrial relaxation. Subgroup analyses of 25 persons of Asian descent showed no significant differences from the rest of the group for all segments. Of all the possible permutations of 3 segments, the best predictive model involves the use of 4 chamber medial septal annulus, 4 chamber mid septum, and apical long axis mid inferolateral segment. The ability to predict was not improved significantly by the use of ≥4 segments.
Conclusion: Global LA strain and strain rates can be accurately predicted from 3 LA segments (4 chamber medial annular and mid septal segments and apical long mid inferolateral segment).
- © 2010 by American Heart Association, Inc.