Mitral Annular Velocities Generated by Speckle Tracking Imaging: Reproducibility and Correlation with Tissue Doppler Velocities

Proximal aortic compliance and diastolic function assessed by speckle tracking imaging

PURPOSE

Speckle tracking imaging (STI) is a recent technique that evaluates an echocardiographic image throughout the cardiac cycle and provides dynamic variables such as tissue velocities and strain rates. The objective of our study was to determine 1) if STI can be used to quantify proximal aortic compliance and 2) if decreased aortic compliance determined by STI will reproduce the previously reported correlation with diastolic function.

METHODS

This was a retrospective observational case series using previously obtained intraoperative transesophageal images. Diastolic performance was quantified by STI-based longitudinal velocities of the basal-septal and basal-lateral walls of the left ventricle in early diastole (LV E'). Change in proximal aortic volume was calculated using STI to measure peak longitudinal and radial velocities in early diastole. After normalizing for mean arterial pressure, compliance was calculated and then compared with basal-septal and basal-lateral LV E' using single regression analysis.

RESULTS

Twenty patients were included in our analysis. Linear regression of basal-septal LV E' and basal-lateral LV E' vs proximal aortic compliance during diastole each resulted in an R(2) value of 0.26 (P < 0.05).

CONCLUSION

Speckle tracking can be used to describe the physical motion of the aortic wall and to calculate its compliance. We confirm that variation in diastolic function can be attributed, in part, to aortic compliance. Our novel approach of measuring compliance throughout the cardiac cycle, isolating radial and longitudinal contributions, and evaluating previously obtained images retrospectively provides advantages over previously reported measures of aortic compliance. Speckle tracking promises new insights into ventricular function, aortic mechanics, and the interaction between these structures.

Diastolic abnormalities in normal phenotype hypertrophic cardiomyopathy gene carriers: a study using speckle tracking echocardiography

BACKGROUND

Tissue Doppler imaging (TDI) of the mitral annulus has been proposed as an alternative for the identification of hypertrophic cardiomyopathy (HCM) genetically affected subjects without left ventricular hypertrophy (G+/LVH-). Unfortunately, conflicting results have been described in the literature, potentially caused by the angle-dependency of TDI. This study sought to assess abnormalities in mitral annular velocities in G+/LVH- subjects as detected by speckle tracking echocardiography (STE).

METHODS

The study population consisted of 23 consecutive genotyped family members without major or minor criteria for the diagnosis of HCM (mean age 37 ± 13 years, 9 men) and 23 healthy volunteers (age 38 ± 12 years, 12 men) who prospectively underwent STE.

RESULTS

There were no significant differences in global peak systolic annular velocity (7.4 ± 1.2 vs. 7.1 ± 1.0 cm/sec) and early diastolic annular velocity (10.2 ± 2.5 vs. 11.3 ± 2.2 cm/sec) between G+/LVH- and control subjects. Global peak late diastolic annular velocity was higher in G+/LVH- subjects (8.1 ± 1.7 vs. 5.7 ± 1.1 cm/sec, P < 0.001). Regionally, this difference was seen in all 6 studied LV walls.

CONCLUSIONS

This STE study confirms our previous TDI observations on increased peak late diastolic annular velocities in G+/LVH- subjects. Because of the complete overlap in early diastolic annular velocities this parameter cannot be used in the genotypes we studied to differentiate genotype (+) from genotype (-) individuals.