Background: Tissue Doppler and Strain rate imaging are relatively load independent. We studied the usefulness of Tissue Doppler and Strain rate imaging in detecting temporal changes in regional and global function of left and right ventricle in transposition of great arteries (TGA).
Methods: Standard echocardiography including Doppler studies was performed with 5 or 10 MHz probe (GE Vivid 7 dimension Machine). The images were analyzed offline by a customized software package (Echo Pac PC,GE Vivid Ultrasound). Intra and inter-observer variability was assessed to be within standard limits. The correlation with surgical outcome will be presented.
Results: A total of 35 patients (aged 3- 123 days) were included in this study. Twelve LV and 2 segments of RV in each patients were analyzed for peak systolic velocity, systolic strain rate and strain. There were no significant intergroup differences in of any of these parameters in patients with or without VSD, or in the groups with regressed or prepared LV. Paradoxically, peak systolic velocity and peak strain rates were statistically significantly higher in patients older than 28 days.
Conclusion: Conventionally classified as regressed LV do not show reduced tissue velocities and strain rates. Peak systolic velocity and peak strain are higher in patients more than 28 days. These findings suggest that possibly intrinsic contractility of the LV myocardium is preserved in a majority of patients with TGA.