Two-dimensional speckle tracking echocardiography for the assessment of atrial function.

Echocardiography is the most common diagnostic method for assessing atrial function but the technique has some limitations. Traditionally, assessment of left atrial function has been performed by measuring volumes with 2D echocardiography. Additionally, it can be assessed with transmitral Doppler and pulmonary vein Doppler. Recently, an alternative method has been incorporated, namely, measurement of myocardial deformation with color tissue Doppler-derived strain. However, this method has several limitations, such as suboptimal reproducibility, angle-dependence, signal artifacts and the fact that it only measures regional strain and does not obtain information about the curved portion of the atrial roof. To overcome these limitations in the quantification of atrial function, the use of speckle tracking echocardiography (STE) strain has been proposed. This technique is not derived from Doppler but rather from 2D echocardiography; it is angle-independent and allows one to measure global as well as regional atrial strain. In this editorial, we describe the physical and pathophysiological concepts of STE and underline the clinical usefulness of this new technique.

Right and left atrial appendage function in patients with mitral stenosis and sinus rhythm.

Tissue Doppler imaging (TDI) is generally used for the assessment of ventricular function, and to a lesser extent, to evaluate the left atrial appendage (LAA). In the present study, we used TDI to analyze the contractile function of the right atrial appendage (RAA). The aim of this study was a comprehensive evaluation of RAA and LAA contractile function in patients with mitral stenosis and sinus rhythm. A total of 69 patients were assessed: group 1 (23 patients with severe MS, 38 +/- 11 years, 20 women), group 2 (23 patients with mild MS, 39 +/- 12 years, 19 women) and group 3 (23 healthy subjects, 42 +/- 14 years, 16 women). Multiplane transesophageal echo was performed in all patients. The RAA was visualized at 130 degrees and the LAA at 0 degrees . TDI sample volume was placed in the tip of both atrial appendages, with an ultrasound beam angle < 10 degrees . Flow velocities and myocardial velocities were measured. The presence of thrombus and/or spontaneous echo contrast (SEC) was assessed. TDI showed in normal subjects, myocardial contraction velocities in RAA similar to that of the LAA (21.8 +/- 4.2 vs. 20.1 +/- 4 cm/s, respectively, P = NS). In patients with MS, myocardial velocities in both atrial appendages were significantly lower than in normal subjects (RAA: 17.4 +/- 5.1 vs. 21.8 +/- 4.2 cm/s, respectively, P < 0.01, LAA: 9 +/- 5.1 vs. 20.1 +/- 4 cm/s, respectively, P < 0.001). Linear regression analysis showed a correlation between the impairment of systolic function of both appendages, pulmonary arterial pressure, valve area and transmitral gradient. Of the 46 patients with MS, patients with intense SEC had lower flow and myocardial velocities in the LAA than patients without SEC (16 +/- 5 vs. 50 +/- 3 cm/s, 6 +/- 2 vs. 10.6 +/- 5.6 cm/s, respectively, P < 0.001 and P < 0.001). In healthy subjects, myocardial contraction velocities in both appendages were similar. Patients with MS and sinus rhythm had contractile dysfunction of both appendages, shown by the decrease in myocardial velocities and related to the increase in atrial afterload. Both appendages exhibited a relation between contractile dysfunction and the presence of SEC, but dysfunction was less marked in the RAA, which might explain the lower prevalence of thrombi in the RAA.

Left and right atrial function after percutaneous mitral valvuloplasty in mitral stenosis and sinus rhythm.

BACKGROUND AND AIM OF THE STUDY: Percutaneous mitral valvuloplasty (PMV) is an effective method for treating patients with severe mitral stenosis. The study aim was to compare left and right atrial appendage functions before and after PMV. METHODS: Twenty-five patients (23 women, two men; mean age 38 +/- 9 years; range: 21-57 years) with severe mitral stenosis and sinus rhythm who underwent PMV were included in the study. Transesophageal echocardiography (TEE) was performed before and at six months after PMV, to evaluate the intensity of spontaneous echo contrast (SEC), left atrial appendage (LAA) dimensions and function, and right atrial appendage (RAA) function. RESULTS: After PMV, the SEC (at TEE) was decreased in all patients, while increases were observed in the contraction and relaxation velocity flows of the LAA (pre-PMV 18 +/- 5 cm/s; post-PMV 24 +/- 9 cm/s; p < 0.001 and pre-PMV 25.5 +/- 10.2 cm/s; post-PMV 32.9 +/- 12.6 cm/s; p < 0.006, respectively). The tissue myocardial velocities were also increased in the LAA (pre-PMV 6.92 +/- 3.77 cm/s; post-PMV 11.16 +/- 6.61 cm/s; p < 0.002) and RAA (pre-PMV 16.2 +/- 3.7 cm/s; post-PMV 19.1 +/- 4.1 cm/s; p < 0.001). CONCLUSION: In patients with mitral stenosis and sinus rhythm, improvements were noted in the left atrial, LAA and RAA systolic functions after PMV. This suggests that the relief of mitral stenosis may not only confer hemodynamic benefits to improve symptoms but also have a favorable influence on future thromboembolic complications. Thus, an early intervention might benefit patients with sinus rhythm by preventing the development of atrial fibrillation and systemic and pulmonary embolism.

Left cavities spontaneous contrast opacification.

We report a transesophageal echocardiography study of a patient in a critical care unit under mechanical respiratory assistance in whom left cavities spontaneous contrast opacification was seen, suggesting systemic gas embolism as the probable mechanism.