Objective: To compare global systolic measurements of mitral annular motion by M-mode and tissue velocity time integral, and annular velocity by pulsed and colour Doppler for precision and bias. Secondly, to compare the ability of annular motion to identify regional dysfunction with segmental analysis by strain rate imaging.
Design: Nineteen normal subjects and 19 patients with myocardial infarction were studied with echocardiography.
Results: There were significant correlations between ejection fraction (EF) and annular motion/velocity by all methods, ranging from 60 to 80%. Measurements had 95% limits of agreement intervals between 7.7 and 15.6 mm for annulus excursion and 8.8 cm/s for annulus velocities with biases between methods of 0.7-1.9 mm and 2.6 cm/s. Annular motion and velocity were reduced in the patients compared with the control group, but were depressed at all points so the infarcted region could not be identified. Only segmental analysis could identify the region of dyssynergy.
Conclusion: Annular motion and velocity measure global function, but have high variability and measurements are method dependent. Only segmental analysis can identify regional dyssynergy. This is possible with strain rate imaging, but the precision is still too low for clinical use.