Tissue Doppler properties of the left atrial appendage in patients with mitral valve disease

OBJECTIVE: The purpose of this study was to compare the left atrial appendage (LAA) tissue Doppler imaging (TDI) with the classical LAA function parameters in patients with mitral valve disease. METHODS: Twenty patients who had pure mitral regurgitation (group 1), 20 patients who had pure rheumatic mitral stenosis (group 2), and 20 healthy patients (group 3) were included in this study. All the cases were sinus rhythm. In order to determine the LAA functions, LAA late filling (LAALF), and late emptying (LAALE) flow velocities and LAA fractional area change (LAAFAC) were measured. LAA tissue Doppler evaluations were obtained from the PW Doppler, which was placed on the LAA lateral wall in a transverse basal short-axis approach. LAA late systolic (LAALSW) and late diastolic (LAALDW) wave velocities were obtained from TDI records transesophageal echocardiography (TEE). RESULTS: There were no significant differences among groups 1, 2, and 3 in terms of age, left ventricular (LV) ejection fraction, gender, and heart rate. No differences were observed between group 1 and the control group with respect to LAALE, LAALF, and LAAFAC. LAALE velocity and LAAFAC were significantly decreased in group 2 than group 1. LV diastolic diameter was significantly greater, whereas LAALSW and LAALDW velocities were significantly decreased in group 1 compared with group 3. There were no differences between groups 1 and 2 regarding to LAALSW and LAALDW velocities. LAALE, LAALF, LAALSW, LAALDW velocities, and LAAFAC were significantly decreased in group 2 than group 3. CONCLUSION: The TDI method may detect the LAA systolic dysfunctions, which cannot be detected using classical methods, on tissue level in patients with mitral regurgitation. In addition, the deterioration of the LAA functions at tissue level in patients with rheumatic mitral stenosis was also detected.     

Color Doppler tissue imaging to evaluate left atrial appendage function in patients with mitral stenosis in sinus rhythm

Two-dimensional color Doppler tissue imaging (CDTI) has so far been used, in general, to evaluate ventricular function. In this study, the left atrial appendage (LAA) tissue velocity was measured by CDTI. LAA function in 38 patients with mitral stenosis in sinus rhythm (SR) and 19 healthy subjects undergoing transesophageal echocardiography were examined by CDTI. Systolic tissue appendage velocity (SaV, m/s) was measured at the tip of the LAA in the basal short-axis view. LAA emptying (LAAEV) and filling (LAAFV) velocities (m/s) were also recorded 1 cm below the orifice of the appendage. LAA ejection fraction was also measured. In addition, two-dimensional imaging was used to determine the presence of thrombus and/or spontaneous echo contrast (SEC). Patients with mitral stenosis in SR had significantly decreased LAAEV, LAAFV, SaV, and LAA ejection fraction compared to controls (0.34 +/- 0.15 vs 0.72 +/- 0.17, 0.37 +/- 0.13 vs 0.63 +/- 0.19, 0.050 +/- 0.015 vs 0.071 +/- 0.093, and 39 +/- 14% vs 69 +/- 13%, respectively, P < 0.001, P < 0.001, P < 0.001, and P < 0.001). Among the patients with mitral stenosis in SR, 10 patients had SEC and one had LAA thrombus. Compared with patients without SEC, patients with SEC had decreased LAAEV, LAAFV, SaV, and LAA ejection fraction (0.24 +/- 0.05 vs 0.37 +/- 0.16, 0.29 +/- 0.05 vs 0.39 +/- 0.14, 0.039 +/- 0.087 vs 0.055 +/- 0.015, and 28 +/- 14% vs 43 +/- 12%, respectively, P = 0.01, P = 0.02, P = 0.01, and P = 0.006). In conclusion, these results suggest that the LAA dysfunction may occur in patients with mitral stenosis in SR and CDTI can successfully be used for the quantification of contraction at the tip of the LAA.     

Right atrial appendage function in patients with chronic nonvalvular atrial fibrillation

To assess right atrial appendage (RAA) flow and its possible relationship to left atrial appendage (LAA) flow in chronic nonvalvular atrial fibrillation (AF), transesophageal echocardiography (TEE) was performed in 26 patients with chronic nonvalvular AF (group I). For the purpose of comparison, an additional group of 27 patients with chronic valvular AF due to mitral stenosis (group II) was analyzed. The clinically estimated duration of AF in group I was significantly longer than that of group II (8.7+/-3.4 versus 2.7+/-1.1 years). Although right atrial size and RAA maximal area were larger in group I than those in group II, left atrial size was larger in group II than that in group I. Group II had larger LAA maximal areas than group I, but this difference did not reach statistical significance. The two groups were not different with respect to the RAA or LAA emptying velocities. Significant correlations were observed between echocardiographic parameters of the two atria in patients with nonvalvular AF (r range, 0.4 to 0.7). In contrast, in patients with valvular AF, no correlation was observed between the echocardiographic parameters of the two atria (appendage emptying velocity, r = 0.38, p = 0.051; atrial size, r = -0.03, p = 0.89; maximal appendage area, r = 0.07, p = 0.75, respectively). There were no significant differences in the presence of right and left atrial spontaneous echo contrast and thrombus between the groups. All of the right and left atrial thrombi were confined to their respective appendages and were found in the atria with spontaneous echo contrast. Both RAA and LAA thrombi were present in one patient. In conclusion, our findings suggest that AF could affect both atria equally in nonvalvular AF, in contrast to valvular AF. Therefore, the assessment of RAA function as well as LAA may be important in patients with chronic nonvalvular AF.     

Assessment of the left atrial appendage mechanical function by three-dimensional echocardiography.

AIMS: We evaluated the feasibility of three-dimensional echocardiography, in the assessment of left atrial appendage (LAA) function. METHODS AND RESULTS: Forty-five patients underwent multiplane transoesophageal echocardiography. In addition to Doppler and two-dimensional echocardiography, data for three-dimensional echocardiography reconstruction were obtained during transoesophageal echocardiography. Left atrial appendage ejection fraction based on three-dimensional echocardiography volume measurements (EFv) and two-dimensional echocardiography area measurements (EFa), coupled with other echocardiographic data, were related to left atrial appendage late peak emptying velocity, a frequently used indicator of left atrial appendage function. Multiple regression analysis has revealed a significant association of peak emptying velocity with EFv (P<0.0001), spontaneous echocardiographic contrast (P=0.001), tricuspid regurgitation (P=0.03) and left ventricular hypertrophy (P=0.05). No significant relation was observed between peak emptying velocity and EFa, presence or absence of atrial fibrillation, left ventricular dysfunction, mitral stenosis and insufficiency, left atrial dilatation, pulmonary venous peak systolic, diastolic and peak reverse flow velocity at atrial contraction as well as left atrial appendage volumes derived from two-dimensional echocardiography and three-dimensional echocardiography. In a simple linear correlation, the degree of association between peak emptying velocity and EFv was higher as between peak emptying velocity and EFa (r=0.7 vs 0.4, both P<0.001). Observer variabilities for calculating EFv were considerably lower than for two-dimensional echocardiography derived EFa. Ejection fractions determined by two-dimensional echocardiography area measurements at 45 degrees, 90 degrees and 135 degrees cutplane angulations were related to EFv only at 135 degrees. CONCLUSIONS: Left atrial appendage ejection fraction calculation by three-dimensional echocardiography is feasible, more accurate than by two-dimensional echocardiography and has lower observer variability. Furthermore, an optimal cutplane angulation of the left atrial appendage view at 135 degrees has been demonstrated.     

Color Doppler tissue imaging to evaluate left atrial appendage function in mitral stenosis

Two-dimensional color Doppler tissue imaging (CDTI) has so far been used, in general, to evaluate ventricular function. This study examined if the left atrial appendage tissue velocity could reproducibly be measured with CDTI and if they have any predictive value for left atrial appendage (LAA) function and former thromboembolism. Thirty-six patients (24 women, 12 men; mean age 45 +/- 12 years; 18 AF; 11 former thromboembolic stroke) with mitral stenosis undergoing transesophageal echocardiography were examined with CDTI. Peak systolic tissue velocity (m/sec, peak systolic velocity [PSV]) was measured at the tip of the LAA in the basal short-axis view. LAA flow emptying (LAAEV) and filling (LAAFV) velocities (m/sec) were also recorded 1 cm immediately below the orifice of the appendage. Interobserver and intraobserver variabilities were determined for the PSV. LAA ejection fraction was measured by Simpson's method. Mitral regurgitation, AF, transmitral mean gradient, left ventricular ejection fraction, mitral valve area, and left atrial diameter were used as a covariant for adjustment. The intraobserver and interobserver correlation coefficients for the PSV using CDTI was 0.64 and 0.60, respectively (bothP = 0.01). LAAEV(0.29 +/- 0.09 vs 0.19 +/- 0.04, P = 0.001)and LAA ejection fraction(44 +/- 12 vs 29 +/- 14, P = 0.004)were found to be significantly decreased in the patients with decreased PSV (<0.05 m/sec), even after adjustment. The decreased PSV was positively correlated with the low LAAEV (<0.25 m/sec) and history of thromboembolism (r = 0.59, r = 0.38, respectively), and remained a significant determinant of the low LAAEV (OR 50.03, CI 1.46-1738.11,P = 0.02), but not of history of thromboembolism (OR 4.29, CI 0.52-35.01,P = 0.08) after adjustment. In conclusion, these results suggest that CDTI provides a reproducible method for quantification of contraction at the tip of the LAA. Decreased PSV may be predictive of poor LAA function.     

Echocardiographic factors predictive of restoration and maintenance of sinus rhythm after reduction of atrial fibrillation

BACKGROUND: Atrial fibrillation (AF) is the most common cardiac arrhythmia. While the arrhythmia was initially thought to be little more than a nuisance, it is now clear that AF has a significant negative impact on quality of life and a corresponding increase in both morbidity and mortality. OBJECTIVE: The aim of this study was to identify Doppler echographic patterns that allow prediction of atrial fibrillation reduction and maintenance of sinus rhythm within 12 months. PATIENTS AND METHODS: One hundred and thirty patients having permanent atrial fibrillation, recent (51) or chronic (79) are included in the study, excepting those with valvular heart disease or thyroid dysfunction. The mean age was 63.5 +/- 11.3 years. Both transthoracic and transoesophageal echocardiography was performed using a Philips SONOS 5500 Echograph, before cardioversion. Were studied: end diastolic and systolic left ventricular diameters, left ventricular ejectionnal fraction, left atrial area (LAA), left atrial diameter, left atrial appendage area and peak emptying velocities of the left atrial appendage (PeV). Sinus rhythm was re-established in 102 patients (44 having recent and 58 chronic atrial fibrillation). Sinus rhythm was maintained for 12 months in 79 patients. RESULTS: Within the echographic parameters studied, the left atrial area (LAA) and peak emptying velocities of left atrial appendage (PeV) before cardioversion were the best predictors of restoration of sinus rhythm. On monovariate analysis, SOG is significantly lower and PicV is significantly higher in patients whose sinus rhythm had been restored in comparison with those with permanent atrial fibrillation. (Mean SOG: 27.7 +/- 7.62 vs. 34 +/- 7,6 cm2, p<0.0001; Mean PicV: 44 +/- 15.8 vs. 31.4 +/- 13,7 cm/s, p<0.0001). This difference was maintained on multivariate analysis (p=0.002 for SOG and p=0.005 for PicV). In patients with recent atrial fibrillation, only left atrial area can predict on mono and multivariate analysis (p=0.05, OR=0.5, IC=0.36 à 3.56), re-establishing of sinus rhythm whereas in patients with chronic atrial fibrillation, peak emptying velocity of left atrial appendage predict better re-establishing of sinus rhythm (p=0.04, OR=1.29, IC=0.12 à 4.23). The threshold values of LAA and PeV for conversion of atrial fibrillation into sinus rhythm are respectively 25 cm2 and 20 cm/sec. In patients who converted into sinus rhythm; LAA predict maintenance of sinus rhythm at the end of 12 months of survey (p=0.04) with a threshold value of 25 cm2. In the subgroup of patients admitted with chronic atrial fibrillation, PeV predicts better the maintenance of sinus rhythm (p=0.05) with a threshold value of 60 cm/sec, p=0.06; whereas LAA remains better in patients with a recent atrial fibrillation. (p=0.02). CONCLUSION: In addition to the anatomic study of cardiac structure and the search of intracavitary thromboses before reduction of atrial fibrillation, echocardiography allows prediction of cardioversion success (LAA and PeV) and maintenance of sinus rhythm within 12 months.     

Influence of acutely altered loading conditions on left atrial appendage flow velocities

Objectives. The purpose of this study was to identify the effects of altered loading conditions on left atrial appendage flow velocities.Background. Although studies have suggested that Doppler analysis of left atrial appendage blood flow may have clinical utility, the hemodynamic and cardiac mechanical determinants of left atrial appendage flow are poorly understood.Methods. Transesophageal Doppler echocardiography was performed in eight atrially paced anesthetized dogs instrumented with sonomicrometers on the left atrial appendage and the left ventricular minor axis and with left atrial and left ventricular micromanometers. Left atrial appendage emptying and filling velocities corresponding to early and late ventricular diastole, respectively, were measured using volume expansion and phenylephrine infusion.Results. Volume infusion caused a significant decrease in the early to late emptying and filling ratios (mean ± SD 0.85 ± 0.24 vs. 0.46 ± 0.17 and 0.80 ± 0.50 vs. 0.40 ± 0.20, both p < 0.05). By contrast, phenylephrine infusion did not significantly alter either filling or emptying ratio. The independent determinants of each flow wave were identified with multiple regression analysis: early emptying velocity—time constant of left ventricular relaxation, left ventricular end-systolic dimension and aortic pressure (r = 0.75, p < 0.001); late emptying velocity—left ventricular peak positive time derivative of left ventricular pressure (dPdt) and fractional shortening (r = 0.74, p < 0.001); early filling velocity—left atrial appendage shortening fraction (r = 0.45, p = 0.01) and late filling velocity—left atrial appendage lengthening rate and left ventricular fractional shortening (r = 0.56, p < 0.01).Conclusions. These results indicate that 1) both the magnitude and the pattern of left atriai appendage emptying and filling velocities are dependent on loading conditions, and 2) left atrial appendage velocities are influenced to a greater extent by changes in left ventricular than in left atrial appendage function. These findings may have implications for the pathogenesis of left atrial appendage thrombi.     

Strain and strain rate imaging in evaluating left atrial appendage function by transesophageal echocardiography

BACKGROUND: This study was planned to assess whether strain rate (Sr) and strain (S) echocardiography is a useful method for functional assessment of the left atrial appendage (LAA). MATERIAL AND METHODS: Fifty-seven consecutive patients underwent a clinically indicated study. LAA late empty velocity (LAAEV) was calculated as a gold standard for left atrial appendage function. Real-time 2-dimensional color Doppler myocardial imaging data were recorded from the LAA at a high frame rate. Analysis was performed for LAA longitudinal strain rate and strain from midsegment of lateral wall of LAA. LAA strain determines regional lengthening expressed as a positive value or shortening expressed as a negative value. Peak systolic values were calculated from the extracted curve. RESULTS: Spearman correlation test results showed a statistically significant positive correlation was between the S, Sr variables and LAAEV (LAAEV vs S; r = 0.886, P < 0.001; LAAEV vs Sr: r = 0.897, P < 0.001, respectively). Strain and strain rate values were also significantly lower in patients with spontaneous echocardiographic contrast when compared with those without (strain; 2.42 +/- 0.98 vs 13.1 +/- 5.9, P < 0.001 and strain rate: 0.97 +/- 0.54 vs 3.34 +/- 1.15, P < 0.001, respectively). In addition, LAA strain and strain rate values were significantly lower in the patients with LAA thrombus (strain; 2.15 +/- 0.96 vs 8.35 +/- 6.9, P < 0.001, strain rate; 0.79 +/- 0.46 vs 2.30 +/- 1.48, P < 0.001, respectively). CONCLUSION: S and Sr imaging can be considered a robust technique for the assessment of the LAA systolic deformation.     

Left atrial appendage dysfunction in chronic nonvalvular atrial fibrillation is significantly associated with an elevated level of brain natriuretic peptide and a prothrombotic state

The study tested the hypothesis that left atrial appendage (LAA) dysfunction in nonvalvular atrial fibrillation (NVAF) correlates with a prothrombotic state, and investigated whether the plasma natriuretic peptides are marker of LAA dysfunction in NVAF. Sixty-seven patients underwent transthoracic and transesophageal echocardiography. The left ventricular fractional shortening, left atrial diameter (LAD), LAA flow velocity and the grade of spontaneous echo contrast (SEC) were determined. The plasma concentrations of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), D-dimer, and thrombin-antithrombin III complex (TAT) were measured. The patients were divided into 2 groups according to LAA flow velocity: group I (LAA velocity <20 cm/s) and group II (LAA velocity > or = 20cm/s). The SEC score, D-dimer, TAT, BNP and LAD were significantly increased in group I. Based on simple linear regression analysis, SEC score (r=-0.638), LAD (r=-0.493), D-dimer (r = -0.485), BNP (r = -0.463), TAT (r = -0.455) and age (r = -0.314) were inversely correlated with LAA flow velocity. Multivariate analysis showed that SEC score (p = 0.0014) and plasma BNP level (p=0.0075) were independent negative predictors for LAA flow velocity. In conclusion, LAA dysfunction is associated with a prothrombotic state, and the plasma BNP concentration may serve as a determinant of LAA function in NVAF.     

Transthoracic Tissue Doppler Assessment of Left Atrial Appendage Contraction and Relaxation: Their Changes with Aging

Aim: We assessed left atrial appendage (LAA) function using transthoracic tissue Doppler echocardiography (TDE), and examined the influence of aging on LAA contraction and relaxation. Methods: The subjects were 45 consecutive patients with heart disease and 110 healthy individuals. LAA wall motion velocity (LAAWV) at the tip of the LAA was measured using transthoracic echocardiography (TTE) and/or transesophageal echocardiography (TEE). Results: We successfully recorded and measured LAAWV using TTE in 105 (95%) of the 110 healthy subjects. When angle correction was applied for the Doppler beam in TTE, LAAWV during contraction (LAAWVc) measured by TTE closely correlated with that measured by TEE (r = 0.97), and LAAWV during relaxation (LAAWVr) measured by TTE closely correlated with that measured by TEE (r = 0.95). LAAWVc and LAAWVr measured by TTE correlated significantly with the LAA flow velocities during LAA contraction and LAA relaxation measured by TEE (r = 0.64, P < 0.001; r = 0.53, P = 0.001). In healthy subjects, although LAAWVc remained unchanged with aging, LAAWVr significantly declined with aging (r =?0.48, P < 0.001) and had a significant negative correlation with left atrial dimension and a significant positive correlation with transmitral flow and annulus velocity during early diastole. Conclusion: Transthoracic TDE can provide information on LAA function. LAA relaxation may be impaired with aging and may be accompanied by early diastolic left ventricular dysfunction and chronic overload to the left atrium. (Echocardiography 2010;27:839‐846)     

Evaluation of Left Atrial Appendage Functions in Patients with Thrombus and Spontaneous Echo Contrast in Left Atrial Appendage by Using Color Doppler Tissue Imaging

Objective: Thrombus and spontaneous echo contrast (SEC) develops in the left atrial appendage (LAA) when LAA function is disturbed. Decrease of left atrial appendage emptying velocity shows LAA dysfunction. The purpose of this study is to examine the incidence of SEC and/or thrombus in LAA in patients with acute myocardial infarction and to assess the LAA function using color Doppler tissue imaging (CDTI) of the patients with detected SEC and/or thrombus. Method and Results: Eighty‐four patients with acute myocardial infarction were included in the study. Spontaneous echo contrast and/or thrombus were observed in 24 (29%) of the 84 patients who were categorized as group 1 (mean age 59 ± 12 years). Sixty patients (71%) without thrombus and/or SEC in LAA were categorized as group 2 (mean age 58 ± 8 years). Left atrial diameters and left ventricular ejection fraction were measured by using transthoracic echocardiography. Left atrial appendage emptying and LAA filling velocity were measured by transesophageal Doppler echocardiography. Systolic appendage tissue velocities (SaV cm/s) were measured at the basal, mid, and tip of medial wall of LAA by transesophageal CDTI. Group 1 had significantly decreased LAA emptying velocities, mid SaVs, and left ventricular ejection fractions compared to group 2 (37 ± 9 cm/s vs 55 ± 22 cm/s, 3.1 ± 1.6 cm/s vs 3.7 ± 1.2 cm/s, and 47 ± 13% vs 58 ± 10%, respectively, P = 0.002, P = 0.04, P = 0.03). Group 1 had significantly increased left atrial diameters compared to group 2 (40 ± 5 mm vs 36 ± 6 mm P = 0.001). Left atrial appendage‐filling velocities, basal SaVs and tip SaVs in group 1 were lower than those in group 2 but not significantly. Conclusions: Mid‐SaV of LAA medial wall and LAA emptying velocity decrease in patients with thrombus and/or SEC were an indication of functional disorder of LAA. Color Doppler tissue imaging appears to be a clinically applicable and reliable imaging technique that allows quantitative assessment of regional LAA systolic function.     

Assessment of left atrial appendage function and its relationship to pulmonary venous flow pattern by transesophageal echocardiography

We evaluated left atrial appendage function and its relationship to pulmonary venous flow in 53 patients divided into four groups. Group 1 consisted of 10 normal subjects. Group 2 included 15 patients with significant pure mitral stenosis in sinus rhythm. In group 3, there were 13 patients with pure significant mitral stenosis and atrial fibrillation. Group 4 consisted of 15 patients with normal mitral valve and atrial fibrilltion. We found significant decrease in left atrial appendage ejection fraction and maximum emptying flow velocity, velocity time integral of systolic pulmonary venous flow in Groups 2, 3 and 4 in comparison with normal subjects. Systolic pulmonary venous flow velocity was significantly decreased in Groups 3 and 4. There was significant correlation between left atrial appendage ejection fraction and peak emptying flow velocity (r = 0.62, P < 0,001). Systolic peak pulmonary venous flow velocity was significantly correlated with left atrial appendage ejection fraction and maximum emptying flow velocity (r = 0.67, P = 0,01; r = 0.58, P < 0,001, respectively). There was also significant correlation between systolic pulmonary venous flow velocity time integral and left atrial appendage ejection fraction (r = 0.66, P = 0.001). When normals were excluded from analysis, all the correlations were still significant. We concluded that left atrial appendage is a contractile structure, and that systolic pulmonary venous flow velocity is influenced by left atrial appendage dysfunction. Therefore left atrial appendage function needs to be considered when interpreting Doppler transmitral and systolic pulmonary venous flow patterns.     

Left atrial appendage flow velocities in subjects with normal left ventricular function

The objectives of this study were to establish reference values and define the determinants of left atrial appendage (LAA) flow velocities in the general population. LAA flow velocities (contraction and filling velocities) were assessed by transesophageal echocardiography in 310 subjects aged > or = 45 years, sampled from the population-based Stroke Prevention: Assessment of Risk in a Community study. All subjects were in sinus rhythm, with preserved left ventricular systolic function (ejection fraction > or = 50%), and without valvular disease. Values of LAA contraction and filling velocities were established for various age groups in the population. Age was negatively associated with LAA contraction and filling velocities, which decreased by 4.1 cm/s (p < 0.001) and 2.0 cm/s (p < 0.01) for every 10 years of age, respectively. Contraction velocities were 5 cm/s higher in men than in women (p < 0.05). After adjusting for age and sex, heart rate was independently associated with LAA contraction velocities (p < 0.001; nonlinear association). Body surface area, left atrial size, left ventricular mass index, and a history of previous cardiac disease or hypertension showed no significant association with LAA flow velocities (p > 0.05). Furthermore, detailed analysis of 24-hour ambulatory blood pressure data (available in 253 subjects) showed no association between various blood pressure parameters (systolic and diastolic blood pressure, out-of-bed and in-bed measurements) and LAA flow velocities (all p > 0.05). In summary, the present study establishes the reference values for LAA flow velocities in a large sample of the general population. LAA flow velocities progressively decline with age in subjects with preserved left ventricular systolic function.     

Mitral annular systolic velocity reflects the left atrial appendage function in mitral stenosis

BACKGROUND: Left atrial appendage (LAA) dysfunction is an independent predictor of thromboembolism in mitral stenosis (MS). OBJECTIVES: To investigate whether there is a relation between annular velocities obtained by tissue Doppler imaging and LAA function and to determine if the annular velocities can predict the presence of the inactive LAA in MS. METHODS: Eighty-five MS patients and 80 healthy controls were evaluated by transthoracic echocardiography and all patients underwent transesophageal echocardiography. The annular systolic (S-wave) and diastolic (E- and A-waves) velocities were recorded. Inactive LAA was defined as LAA emptying velocity <25 cm/sec. Patients were divided into three groups; group I (n = 43): sinus rhythm (SR) and LAA emptying velocity > or =25 cm/sec, group II (n = 15): SR and LAA emptying velocity <25 cm/sec and group III (n = 27): atrial fibrillation. RESULTS: Thrombus was detected in 12 patients and spontaneous echo contrast (SEC) was detected in 48 patients. Both S-wave and peak LAA emptying velocities were decreasing, while SEC frequency and density were increasing from group I to group III. There was a positive correlation between LAA emptying and S-wave velocities (P < 0.001, r = 0.682). Multivariate regression analysis showed that only S-wave is the independent predictor of inactive LAA (P = 0.001, odds ratio = 0.143, 95% CI = 0.047-0.434). In patients with SR, the cutoff value of S-wave was 13.5 cm/sec for the prediction of the presence of inactive LAA (sensitivity: 95.3%, specificity: 93.3%). CONCLUSIONS: S-wave is an independent predictor of inactive LAA and a useful parameter in estimating inactive LAA in MS with SR.     

Transthoracic Doppler echocardiographic measurement of left atrial appendage blood flow velocity: comparison with transoesophageal measurement.

AIM: We validated transthoracic echocardiographic measurements of left atrial appendage flow velocity by comparing them with transoesophageal echocardiographic measurements. METHODS AND RESULTS: Eighty-four consecutive patients (mean age, 64.6 years) with various cardiac diseases, who underwent both transthoracic echocardiography and transoesophageal echocardiography were studied. Thirty-two patients were in sinus rhythm, and the remaining 52 patients were in atrial fibrillation. On transthoracic echocardiography, the transducer was placed somewhat superior and outside from the position viewing the conventional parasternal short-axis image of the aortic valve, so that the angle between left atrial appendage midline and Doppler beam could be narrowed. The left atrial appendage flow velocity pattern was recorded by pulsed Doppler mode with a sampling volume placed at the left atrial appendage orifice on both transthoracic echocardiography and transoesophageal echocardiography. In both approaches, the peak emptying velocity (LAA-E) and the peak filling velocity (LAA-F) of the left atrial appendage were measured. In sinus rhythm, the LAA-E was detectable in 25 of the 32 patients (78.1%) and the LAA-F in 20 of the 32 patients (62.5%). Both LAA-E and LAA-F were detectable in 46 of the 52 patients (88.5%) in atrial fibrillation. Good correlations of LAA-E and LAA-F were observed between transthoracic echocardiography and transoesophageal echocardiography measurements in sinus rhythm (r=0.94, r=0.95, respectively; both, P<0.0001) and in atrial fibrillation (r=0.89, r=0.95, respectively; both, P<0.0001). CONCLUSIONS: The left atrial appendage flow velocities could be sufficiently recorded and assessed by transthoracic echocardiography in 84 Japanese unselected consecutive patients with sinus rhythm or atrial fibrillation.     

P wave dispersion and left atrial appendage function for predicting recurrence after conversion of atrial fibrillation and relation of p wave dispersion to appendage function

BACKGROUND: We investigated P wave dispersion and left atrial appendage (LAA) function for predicting atrial fibrillation (AF) relapse, and the relationship between P wave dispersion and LAA function. METHODS: Sixty-four consecutive patients with AF lasting /=5 days, LA size >/=45 mm, maximum P wave duration >/=112 ms, P wave dispersion >/=47 ms, spontaneous echo contrast, minimum LAA area >/=166 mm(2), and LAA emptying velocity <36 cm/sec were univariate predictors of recurrence (each P < 0.05). By multivariate analysis, LA size (P = 0.02), P wave dispersion (P < 0.001), and LAA emptying flow (P = 0.01) identified patients with recurrent AF. Their positive predictive values were 91, 97, and 72%, respectively. CONCLUSION: The increased P wave dispersion in addition to the dilated LA and the depressed LAA emptying flow can identify patients at risk of recurrent AF after cardioversion.     

Can Left Atrial Strain and Strain Rate Imaging Be Used to Assess Left Atrial Appendage Function?

Background: The aim of this study was to evaluate the efficiency of left atrial strain (S) and strain rate (SR) imaging in assessing left atrial appendage (LAA) function. Methods: We studied 78 consecutive patients (35 females and 43 males; mean age 38 ± 15 years) referred for transesophageal echocardiography (TEE). LAA late emptying velocity (LAA-EV) was calculated. Real-time color Doppler myocardial velocity imaging (MVI) data were recorded from the LAA by TEE and the lateral wall of the left atrium (LA) by transthoracic echocardiography. Longitudinal S and SR were measured in the mid portion of the lateral LA wall and lateral LAA wall during the contractile period. LAA late systolic velocity (LSV) and LA-LSV were obtained from Doppler analysis. Results: A significant positive correlation was detected between LAA-EV and MVI parameters (for LAA-S, r = 0.88, p < 0.001; for LAA-SR, r = 0.84, p < 0.001; for LAA-LSV, r = 0.83, p < 0.001; for LA-S, r = 0.84, p < 0.001; for LA-SR, r = 0.79, p < 0.001, and for LA-LSV, r = 0.70, p < 0.001). In addition, a significant positive correlation was detected between LAA-S and LA-S (r = 0.85, p < 0.001). Conclusion: We suggest that LA-S and LA-SR imaging is a beneficial method to evaluate LAA functions noninvasively.     

Atrial myocardial deformation properties are temporarily reduced after cardioversion for atrial fibrillation and correlate well with left atrial appendage function.

AIM: This study was conducted to evaluate whether left atrial strain and strain rate correlate well with transesophageal parameters of stunning after atrial fibrillation. METHODS AND RESULTS: Twenty-two consecutive patients with chronic atrial fibrillation >/=3 months and <1 year were enrolled in the study. Transthoracic (TTE) and transesophageal (TEE) echocardiography with color Doppler myocardial imaging were performed before, 1 day after and 10 days after successful cardioversion. Left atrial transthoracic strain (S) and strain rate (SR) from lateral, inferior and anterior atrial walls, left atrial appendage tissue velocities, strain and strain rate values were measured with offline analysis. Left atrial appendage emptying (LAAEV) and filling (LAAFV) velocities were obtained from transesophageal echocardiography. Left atrial transthoracic, and left atrial appendage strain and strain rates were significantly lower following 1 day after cardioversion (TTE S/SR, 5.0 +/- 2.8%/2.3 +/- 1.0; TEE (septal) S/SR, 7.6 +/- 3.6%/1.6 +/- 0.7). There was a good correlation between these parameters and LAAEV (LA systolic strain and LAAEV, r = 0.73, P = 0.007). Left atrial and LAA strain and strain rate values improved over time, and correlated well with LAAEV, measured 10 days after cardioversion. CONCLUSIONS: Transthoracic atrial and TEE LAA strain and strain rate, which are quantitative measures of atrial function, are reduced after cardioversion, and recover subsequently. The good correlation between LAA function and TTE strain and strain rate suggests that TTE atrial parameters may help determine duration of anticoagulation.     

Assessment of left ventricular mass in mice: comparison between two-dimensional and m-mode echocardiography

OBJECTIVE: M-mode echocardiography has been used extensively for estimating left ventricular (LV) mass in mice, but accuracy is limited by its unidimensional nature. This study tested whether two-dimensional (2-D) echocardiographic measurement of LV mass using area-length and truncated ellipsoid methods overcomes this limitation. METHODS: Twenty-five anesthetized FVB/N mice (Mus musculus) underwent high resolution (15 MHZ) two-dimensionally directed M-mode and 2-D echocardiography. End-diastolic epicardial and endocardial areas from short-axis views and the LV orthogonal long-axis views were measured, while LV mass was calculated by 2-D area-length and truncated ellipsoid methods. LV mass was calculated from M-mode using the uncorrected cube equation. Hearts were removed and weighed after completing the echocardiographic studies. The correlation and agreement between echocardiographic-determined LV mass and gravimetric LV weight were examined. RESULTS: LV mass using the area-length method correlated better with autopsy LV weight (r = 0.87, slope = 0.87, standard error of the estimate [SEE] = 12.4 mg, P < 0.001) than M-mode echocardiography (r = 0.85, slope = 0.71, SEE = 11.1 mg, P < 0.001), and the degree of agreement (bias +/- 2 SD) was better (10.2 +/- 25.1 mg vs 13.1 +/- 25.8 mg, P = NS). Although 2-D truncated ellipsoid LV mass showed a good correlation with necropsy LV weight (r = 0.87, slope = 0.78, SEE = 11.0 mg, P < 0.001), the agreement between the truncated ellipsoid estimates and LV weight was less than that between M-mode and gravimetric LV mass. CONCLUSIONS: The 2-D area-length method is an accurate method of LV mass determination in symmetrical ventricles and can be used as an alternative for in vivo measurement of LV mass in mice.