TM sections of the left ventricle (LV) have only been validated in fundamental (F) imaging. We were interested in evaluating the repercussions of new imaging techniques, harmonic (H) and colour tissue Doppler (CTD), on the TM measurement of left ventricular mass (LVM), the reference imaging being F imaging.
Method: We performed a prospective study, including 26 patients with a valid TM section. The LV and LVM parameters in F, H and CTD mode according to the Penn and ASE conventions as well as the inter-observer reproducibility were studied.
Results: The correlations for the LVM measurements between F and H, and between F and CTD were high whichever convention was used (r>0.95, p<0.0001). For each observer, the LVM in H and in CTD was always greater than the LVM in F with both conventions (p<0.02). A false diagnosis of LV hypertrophy was made in 27% of patients in H and in 15% of patients in CTD. The best inter-observer reproducibility was obtained in H: the average inter-observer difference (gr.) was 23+/-15 for H, 32+/-19 for F and 59+/-18 for CTD.
Conclusion: H and CTD imaging entail an overestimation of LVM, essentially by overestimation of the parietal thickness of the LV. The inter-observer reproducibility was excellent in H and poor in CTD. The use of the harmonic mode for LVM calculation must be validated using new formulae.