Left and right atrial myocardial deformation properties in patients with an atrial septal defect

Background: Atrial septal defect (ASD) is a common form of congenital heart defect in adults, which affects all cardiac chambers. Atrial myocardial function in patients with ASD has not yet been clearly elucidated. The aim of this study was to investigate atrial myocardial deformation properties in patients with ASDs. Methods: The study involved 24 patients with a secundum type ASD, and 22 healthy subjects. Color Doppler myocardial imaging was used to measure left and right atrial myocardial systolic strain and strain rate values, together with peak systolic velocity, early velocity, and late diastolic velocity. Results: There was no significant difference between the two groups with regard to age, gender, body mass index, heart rate, blood pressure, left atrial diameter, and ventricular function. The peak systolic atrial myocardial strain and strain rate values in each of the atrial walls studied were lower in the ASD group compared to those of the control group, but the difference reached statistical significance only in the case of the right atrial wall (right atrial strain: 48.0 ± 32.7% vs 100.2 ± 46.6%, P = 0.006; right atrial strain rate: 2.6 ± 1.2/sec vs 3.8 ± 1.2/sec, P = 0.024). Conclusion: The left to right cardiac shunt that results from ASD leads to a reduction in the right atrial myocardial longitudinal lengthening that occurs during ventricular ejection. These findings demonstrate that the reservoir function of the atrium is impaired and atrial stiffness increases in patients with ASDs.     

Depressed Atrial Function in Diastolic Dysfunction: A Speckle Tracking Imaging Study

Background: Two‐dimensional speckle tracking imaging (STI) has recently been applied to the study of left atrial (LA) reservoir function. We utilized STI to analyze LA function in diastolic dysfunction (DD), hypothesizing that LA strain abnormality is part of the pathogenesis of diastolic dysfunction. Methods: We applied STI to 50 patients with Grade 1‐2 DD, comparing these results to 100 normal controls. Complete Doppler analysis of filling was made using peak E, peak A and tissue Doppler e' velocities; E/e' was used as a surrogate for LA pressure and LA stiffness index was calculated. Results: In analysis of covariance, adjusting for age and gender, compared with controls, DD patients had higher E/e', greater LA volume and greater LA stiffness, but lower E/A ratio and global LA strain. LA strain appears to be inversely related to LA volume, but not to other indices of LV diastolic function. In subgroup analysis, LA strain was significantly lower, and stiffness significantly higher in DD, even after correction for differences in LA volume and E/A ratio. Analysis of ROC curves suggests that abnormal LA strain is a better marker for diastolic dysfunction than LA enlargement. Conclusion: LA strain by STI is significantly reduced in early diastolic dysfunction and is related to higher LA stiffness and LA size. Reduction in LA strain is partially independent of LA volume; accordingly we hypothesize that reduced atrial strain indicates impaired atrial distensibility.     

Intraobserver reliability of two-dimensional ultrasound derived strain imaging in the assessment of the left ventricle, right ventricle, and left atrium of healthy human hearts

Aims: To determine the intraobserver reproducibility of peak and temporal values for myocardial strain (?) and strain rate (SR) using a speckle tracking technique in the left ventricle (LV), right ventricle (RV), and left atrium (LA). Methods and Results: Myocardial speckle tracking echocardiograms of the LV, RV, and LA were obtained on 20 healthy adults to provide indices of longitudinal, radial, circumferential ?, and SR as well as LV rotation and twist. Each participant had two separate acquisitions approximately 30 minutes apart. No systematic bias was present in ? data. LV ? across all planes provided “good” to “very good” intraclass correlation coefficient (ICC) values (0.714–0.807), however radial ? was inferior in terms of coefficients of variation (CoV) (19%). SR data were more variable than ? with LV radial SR performing least favorably. RV and LA ? demonstrated excellent reproducibility (ICCs of 0.834, 0.959, and CoVs of 7% and 6%, respectively). RV and LA SR were again more variable but generally acceptable ICC > 0.6 and CoV < 15%. Peak basal and apical rotation demonstrated quite high variability while derived torsion had low variability and excellent agreement (ICC = 0.940, CoV = 10%). Time‐to‐peak values demonstrated acceptable agreement with the exception of systolic SR from all chambers. Conclusion: Good reproducibility was obtained for peak ? indices although radial ? performs less favorably. Intraobserver variation of peak ? appears superior to values obtained for peak SR. Time‐to‐peak values demonstrate very good intraobserver reproducibility across all planes of contraction with exception of (time‐to‐peak) systolic strain rate (SRS).