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Background: The interaction between local myocardial motion and blood flow dynamics should be assessed to evaluate left ventricular pump function. Methods: The contour map of the absolute value of blood flow velocity in the left ventricle (LV) was drawn. The ridgeline of the contour was defined as the 'flow axis line'. LV wall motion was assessed by the tracing endocardial border in consecutive B-mode images and by myocardial tissue velocity distribution obtained by the optical flow method. Results: The location of the main flow axis line was affected by the local myocardial movement in the short axis direction. The flow axis line method is superior to the previous investigations on two-dimensional blood flow analysis because it considered three-dimensional blood flow. Conclusions: The flow axis line represents not only intracardiac blood flow structure but also its interaction with the cardiac wall motion. [ABSTRACT FROM AUTHOR]

Tissue Doppler imaging (TDI) plays an important role in assessing diastolic function using echocardiography. However, two different methods [pulsed wave (PW-TDI) and color-coded (CC-TDI)] are currently used. We aimed to compare both measurements. We included 114 patients that were referred to our echocardiography department for evaluation of diastolic left ventricular function. In these patients, we sequentially measured tissue velocities of basal lateral and septal myocardium of the left ventricle in an apical four-chamber view with both PW-TDI and CC-TDI. Our cohort consisted of a heterogeneous group of patients with and without a history of cardiac disease. Mean age of the patients was 52 ± 16.7 years, and 62% were males. We found a strong correlation between PW-TDI- and CC-TDI-derived myocardial velocities ( r = 0.93; p = 0.001). However, E′ (mean of lateral and septal) velocities measured with PW-TDI were consistently higher compared to CC-TDI values [PW-TDI E′ 10.3 ± 3.9 (SD) cm/s vs. CC-TDI E′ 7.7 ± 3.1 cm/s; p < 0.001]. From these data, we calculated that the relation between E′ measured with PW-TDI and CC-TDI can be described as: E′ (PW-TDI) = 1.25 + 1.17 × E′ (CC-TDI). Consequently, E/E′ measured with PW-TDI was consistently lower compared with CC-TDI (9.1 ± 3.1 vs. 12.5 ± 5.7; p < 0.001) From these data, we calculated that the relation between E/E′ measured with PW-TDI and CC-TDI can be described as: E/E′ (PW-TDI) = 2.13 + 0.56 × E/E′ (CC-TDI). Despite a strong correlation, tissue velocities measured with PW-TDI will yield higher values as compared with CC-TDI. This should be taken into account when defining cut-off values for the evaluation of diastolic function. [ABSTRACT FROM AUTHOR]

This study applied tissue Doppler imaging and color tissue Doppler imaging to study atrial function changes in patients with hypertrophic cardiomyopathy (HCM). The profile of the segmental atrial velocities and the strain rate were determined and compared with those of normal matched control subjects. This study investigated 20 patients with HCM and 20 age-matched healthy control subjects. In a four-chamber apical view, tissue Doppler imaging was used to measure the lateral left and right atrial (LA and RA) and interatrial septal (IAS) wall systolic, early, and late diastolic velocities. Similarly, the atrial strain rate during ventricular systole (SRS) and the early (SRE) and late (SRA) diastolic phases in patients and control subjects were measured. The interventricular septal tissue Doppler-derived isovolumic relaxation time was calculated. Only the IAS annular and middle segments showed a significant reduction in the early diastolic velocity (mean, 4.01 ± 2.2 vs 8.7 ± 1.1, p = 0.001; 3.23 ± 2 vs 6.01 ± 1.9, p = 0.001, respectively) for the patients with HCM in comparison with the control subjects. Generally, the atrial strain rate was clearly reduced. The systolic strain rate (SRS) was significantly reduced in the LA wall in the annular ( p = 0.007) and middle ( p = 0.001) segments and in the IAS middle segment ( p = 0.007). Similarly, there was a reduction of the early diastolic strain rate (SRE) in the LA annular ( p = 0.001) and middle ( p = 0.01) segments and in the IAS annular ( p = 0.05) and middle ( p = 0.001) segments, as well as in the RA annular segment ( p = 0.02). The RA middle segments showed insignificant changes. Atrial function may be affected by HCM due to impairment of myocardial diastolic function. Strain rate imaging is reproducible, yields readily obtained parameters that provide unique data about global and longitudinal segmental atrial contraction, and can quantify the atrial dysfunction in patients with HCM. [ABSTRACT FROM AUTHOR]

Autocorrelation using in-phase and quadrature (IQ) signals suffers from aliasing when the velocity of rapidly moving tissue, such as the heart wall, is measured. In the present study, a simple method was proposed to expand the aliasing limit. In the proposed method, the velocity difference between two successive frames (corresponding to acceleration) of tissue was also estimated directly from IQ signals. When aliasing occurs in the velocity in the current frame, which was estimated from IQ signals, the velocity in the current frame was corrected by adding the velocity difference to the velocity in the previous frame. Using this procedure, the velocity can be estimated if the difference between velocities in the current and previous frames is less than the aliasing limit. The velocity of the posterior heart wall in the longitudinal-axis view of about 0.08 m/s could be estimated under the aliasing limit of the conventional autocorrelation method of 0.047 m/s. Myocardial velocity over the conventional aliasing limit could be measured by the proposed method. [ABSTRACT FROM AUTHOR]