Abstract 20202: Regional Myocardial Function in Pediatric Patients After Anthracycline Exposure. The Effect of Afterload on Strain and Strain Rate Measurements.
Background: As more children survive chemotherapy for childhood cancer, early detection of cardiac dysfunction becomes important on long term follow up. Strain and strain rate measurements have been proposed for early detection of late anthracycline toxicity. The effect of increased wall stress on these measurements has, however, not been assessed. We hypothesized that strain rate measurements would be less dependent on afterload than end systolic strain measurements.
Methods: We included 71 children (10–18y) > 5years after anthracycline treatment (ANT) and 41 age-matched controls. Peak systolic wall stress was calculated. Myocardial deformation parameters (radial, longitudinal strain and strain rate and circumferential strain) were assessed using 2D speckle tracking ( EchoPac, GE). Student t test was used to compare the 2 groups. Linear regression analysis was performed to study the relationship between wall stress and deformation measurements.
Results: Table 1 summarizes the results. Peak systolic wall stress was significantly higher in the ANT group. No significant differences in radial strain and strain rate were found. Global circumferential strain was significantly decreased both at base and papillary muscle level. Longitudinal strains in the basal and mid septal segments were decreased in the ANT group. Wall stress correlated with global circumferential strain at papillary muscle level, r=0.32, p=0.005 in the ANT group. No correlations between wall stress and peak systolic strain rate was found.
Conclusions: Decreased strain values in patients after anthracycline exposure may be partially explained by increased wall stress. Strain rate values seem less dependent on wall stress and may provide better information on myocardial function in this group.
- © 2010 by American Heart Association, Inc.