How should we measure left atrium size and function?

The effect of different preoperative left atrial appendage emptying speeds on left atrial function in patients with persistent atrial fibrillation after left atrial appendage closure combined with catheter ablation

Objective

The present study aimed to investigate whether different preoperative left atrial appendage emptying speeds (LAAEVs) have an effect on left atrial function in patients with sinus arrhythmia after left atrial appendage closure (LAAC) combined with catheter ablation (CA).

Methods

A total of 163 patients with persistent non-valvular atrial fibrillation who received combined LAAC+CA surgery were included in the present study. Regular follow-up was conducted for 12 months, and patients with complete data and successful sinus rhythm recovery were selected as the study subjects (n = 82). The patients were divided into two groups: the LAAEV < 25 cm/s group and the LAAEV ≥ 25 cm/s group (n = 41 each). The propensity score was used for matching according to gender, age, CHA₂DS₂-VASc score, and HAS-BLED score. The changes in the two groups in LA structure, storage function, conduit function, and pump function were compared.

Results

Before surgery, the maximum LA volume (LAV_max) and minimum LA volume (LAV_min) were greater in the LAAEV < 25 cm/s group than in the LAAEV ≥ 25 cm/s group. The LA storage function (eg. Ƹ and SRs), conduit function (eg. SRe), and pump function (eg. SRa) were all worse in the LAAEV < 25 cm/s group than in the LAAEV ≥ 25 cm/s group. After the combined LAAC+CA surgery, the LA storage, conduit, and pump functions improved in both groups. At 12 months after surgery, there were no statistically significant differences between the two groups.

Conclusion

Before combined LAAC+CA surgery, the LA structure and function of the LAAEV < 25 cm/s group were worse than those of the LAAEV ≥ 25 cm/s group. However, after LAAC+CA surgery, the LA structure and function of the patients were improved, and there were no significant differences between the two groups. Inferred improvement in LA structure and function in the LAAEV < 25 cm/s group was superior to that in the LAAEV ≥ 25 cm/s group.

Effect of coronavirus disease-2019 infection on left atrial functions

Objective:

Left atrial (LA) dysfunction is a crucial risk factor for cardiovascular events, and various pathologies may affect LA function. Coronavirus disease-2019 (COVID-19) is an ongoing global pandemic causing morbidity and mortality. In the present study, we aimed to evaluate LA functions in patients who recovered from COVID-19.

Methods:

Sixty consecutive patients recovered from COVID-19 and 60 healthy individuals as a control group were included in the study. Blood samples and echocardiography measurements were obtained from each subject. The two groups were compared in terms of demographic and echocardiographic characteristics.

Results:

In the COVİD-19 group, LA maximum volume (LAV_max) (P = 0.040), LA pre-A volume (LAVpre-A) (P = 0.014), and LA active emptying fraction (P = 0.027) were higher, while LA passive emptying fraction (P = 0.035) was lower. In addition, left ventricular ejection fraction (P = 0.006) and isovolumetric relaxation time (P = 0.008) were decreased in this group. Although LA volume index was higher in the COVID-19 group, it does not reach statistical significance.

Conclusion:

LA functions may be impaired in patients recovered from COVID-19 infection.

Endocrine and Mechanical Cardiacfunction Four Months after Radiofrequency Ablation of Atrialfibrillation

Background

Radiofrequency ablation (RFA)is an important treatment option for patients with atrial fibrillation (AF). During RFA, a significant amount of energy is delivered into the left atrium (LA), resulting in considerable LA-injury. The impact of this damage on mechanical and endocrine LA-function, however, is often disregarded.We therefore aimed to evaluate the endocrine- and mechanical function of the heart 4-months after RFA of AF.

Methods

In total 189 patients eligible for RFA of AF were studied. The levels of the N-terminal pro-B-natriuretic peptide (NT-proBNP) and the mid-regional fragment of the N-terminal pro-atrial natriuretic peptide (MR-proANP)were measured. The maximum LAvolume (LAVmax),the LAejection fraction (LAEF) and the LA peak longitudinal strain (PALS), were measured usingtransthoracic echocardiography. The measurements were performed before and 4-months after the intervention.

Results

87 patients had a recurrence during a mean follow-up of 143±36 days.NT-proBNPand MR-proANPdecreased significantly at follow-up. This reduction was greater in patients who did not suffer any recurrence after RFA.The LAVmax decreased significantly, whereasthe PALS only improved in patients who did not suffer from any recurrence. On the other hand, LAEF did not change significantly after RFA of AF.

Conclusions

Despite extensiveablation during RFA of AF, the endocrine function of the heart improved 4-months after the index procedure. Patients with no arrhythmia recurrence showed a more pronounced improvement in their endocrinal function. Mechanically, the LAVmax was reduced, and the LA strain improved significantly.

Distorted assessment of left atrial size by echocardiography in patients with increased aortic root diameter

Background

Left atrial (LA) size is frequently assessed by posterior-anterior linear measurement of LA (LAD P-A) in the parasternal long axis to expedite examination. Aging, changes in body surface area, and several cardiovascular pathologies can affect aortic root (AoR) size, thereby affecting LA anatomical shape. We hypothesized that AoR dilatation influences LAD P-A and consequently correct assessment of LA size.

Results

We tested our hypothesis in a study of 70 patients with AoR diameter ranging from 2.7 to 4.8 cm. LA size assessed in parasternal long axis view as LAD P-A was compared to that with LA width and length acquired in the apical two and four chamber view. Simpson’s method of discs was used as standard measurement to assess LA volume.

We observed that LAD P-A in the parasternal long axis decreases when AoR diameter increases. Thus, the increase in LA size assessed in parasternal long axis did not correlate with the increase of LA volume. Further analysis revealed that a significant positive correlation was observed when LAV was plotted as a function of LAD P-A only for those with a normal size AoR. In contrast, LA volume increase correlated with LA diameters assessed in the apical two and four chamber view regardless of AoR size.

Conclusions

Our study documents that increases in AoR impact on the linear measurement of LA, resulting in an underestimated LAD P-A. LA size ought to be calculated from the apical two and four chambers view parameters, especially in patients with AoR dilatation.

Left atrial speckle tracking echocardiography in clinically healthy dogs: Variability and prediction intervals

Left atrial (LA) speckle tracking echocardiography (STE) provides indices of LA deformation such as strain and strain rate. These variables offer useful clinical information in human and canine patients with cardiac disease. At present, reference ranges for LA STE variables in dogs are scarcely established and, due to variability among centers, they cannot be accepted worldwide. The present study aimed to provide normal ranges for LA strain and strain rate variables in clinically healthy dogs, and to evaluate the effect of clinical parameters such as bodyweight. Eighty clinically healthy dogs served as the study population. Left atrial STE was feasible in all dogs and agreement within and between observers was clinically acceptable for most of the variables, in particular strain variables. Age, sex, and heart rate did not affect LA STE. Bodyweight was negatively correlated with strain variables and positively correlated with diastolic strain rate variables and the relationship was allometric. Bodyweight-based vendor-dependent prediction intervals for LA STE variables in clinically healthy dogs could aid the evaluation of LA function in clinical practice.

Assessment of left atrial function in feline hypertrophic cardiomyopathy by using two- dimensional speckle tracking echocardiography

BACKGROUND

Left atrial (LA) function plays an important role in diastolic dysfunction in cats with hypertrophic cardiomyopathy (HCM). Two-dimensional speckle tracking echocardiography (2D-STE) is a technique for assessing LA function. This study aimed to evaluate the LA function in HCM cats compared to normal cats, using 2D-STE.

RESULTS

Seventeen client-owned cats affected with HCM and twenty healthy control cats were studied. Conventional echocardiographic and 2D-STE variables were measured and compared between groups (control and HCM groups). Variability of the peak atrial longitudinal strain (PALS) displayed good reproducibility with 4.7% intra-observer and 14% inter-observer repeatability. The mean value of PALS in the HCM group (13.16 ± 8.64) was lower than that in the control group (28.54 ± 10.31) (P < 0.001). PALS was lowest in the LA roof region. The atrial longitudinal strains of septal and lateral regions were significantly lower in the HCM group than in the normal group. The PALS correlated with the percentage of the LA fractional shortening (LA-FS) (r = 0.538, P = 0.001), the percentage of the LA ejection fraction (LA-EF) (r = 0.797, P < 0.001), and the LA fractional area change (FAC) (r = 0.746, P < 0.001).

CONCLUSIONS

PALS is a feasible and reproducible method to evaluate the LA function in cats affected with HCM.

Assessment of left atrial function in feline hypertrophic cardiomyopathy by using two- dimensional speckle tracking echocardiography

BACKGROUND

Left atrial (LA) function plays an important role in diastolic dysfunction in cats with hypertrophic cardiomyopathy (HCM). Two-dimensional speckle tracking echocardiography (2D-STE) is a technique for assessing LA function. This study aimed to evaluate the LA function in HCM cats compared to normal cats, using 2D-STE.

RESULTS

Seventeen client-owned cats affected with HCM and twenty healthy control cats were studied. Conventional echocardiographic and 2D-STE variables were measured and compared between groups (control and HCM groups). Variability of the peak atrial longitudinal strain (PALS) displayed good reproducibility with 4.7% intra-observer and 14% inter-observer repeatability. The mean value of PALS in the HCM group (13.16 ± 8.64) was lower than that in the control group (28.54 ± 10.31) (P < 0.001). PALS was lowest in the LA roof region. The atrial longitudinal strains of septal and lateral regions were significantly lower in the HCM group than in the normal group. The PALS correlated with the percentage of the LA fractional shortening (LA-FS) (r = 0.538, P = 0.001), the percentage of the LA ejection fraction (LA-EF) (r = 0.797, P < 0.001), and the LA fractional area change (FAC) (r = 0.746, P < 0.001).

CONCLUSIONS

PALS is a feasible and reproducible method to evaluate the LA function in cats affected with HCM.

Echocardiographic and Biochemical Factors Predicting Arrhythmia Recurrence After Catheter Ablation of Atrial Fibrillation-An Observational Study

Background: RFA is a well-established treatment for symptomatic patients with AF. However, the success rate of a single procedure is low. We aimed to investigate the association between the risk of recurrence of atrial fibrillation (AF) after a single radiofrequency ablation (RFA) procedure and cardiac neurohormonal function, left atrial (LA) mechanical function as well as proteins related to inflammation, fibrosis, and apoptosis.

Methods and Results: We studied 189 patients undergoing RFA between January 2012 and April 2014, with a follow-up period of 12 months. A logistic regression analysis was performed to investigate the association between pre-ablation LA emptying fraction (LAEF), MR-proANP, Caspase-8 (CASP8), Neurotrophin-3 (NT3), and the risk for recurrence of AF after a single RFA procedure. 119 (63.0%) patients had a recurrence during a mean follow-up of 402 ± 73 days. An increased risk of recurrence was associated with: Elevated MR-proANP (fourth quartile vs. first quartile: HR, 2.80 (95% CI, 1.14–6.90]; P = 0.025); Low LAEF (fourth quartile vs. first quartile: hazard ratio [HR], 2.41 [95% CI, 1.01–5.79]; P = 0.045); Elevated CASP8 (fourth quartile vs. first quartile: HR 12.198 95% CI 2.216–67.129; P = 0.004); Elevated NT-3 (fourth quartile vs. first quartile: HR 7.485 95% CI 1.353–41.402; P = 0.021). In a receiver operating characteristic curve analysis, the combination of MR-proANP, CASP8, and NT3 produced an area under the curve of 0.819; CI 95% (0.710–0.928).

Conclusions: Patients with better LA mechanical function and lower levels of atrial neurohormones as well as of proteins related to fibrosis and apoptosis, have a better outcome after an RFA procedure.

Unique identifier: No. NCT01553045 (https://clinicaltrials.gov/ct2/show/NCT01553045?term=NCT01553045&rank=1).

Assessment of left atrial volume in dogs: comparisons of two-dimensional and real-time three-dimensional echocardiography with ECG-gated multidetector computed tomography angiography

INTRODUCTION

We hypothesized that real-time three-dimensional echocardiography (RT-3DE) was superior to two-dimensional echocardiography for the estimation of left atrial volume (LAV), using electrocardiographic (ECG)-gated multidetector computed tomography angiography (MDCTA) as a volumetric gold standard. The aim was to compare maximum LAV (LAV_max) and minimum LAV (LAV_min) measured by biplane area-length method (ALM), biplane method of disk (MOD) and RT-3DE with 64-slice ECG-gated MDCTA in dogs ANIMALS: The study included twenty dogs, anaesthetized for various diagnostic purposes and without evidence of cardiovascular disease.

METHODS

Left atrial volume was estimated by ALM, MOD and RT-3DE following ECG-gated MDCTA. The results were compared with LAV from MDCTA and correlations were performed. The limits of agreement (LoA) between methods were evaluated using Bland-Altman analysis and intraclass correlations. Coefficients of variation were calculated.

RESULTS

Area-length method (r = 0.79 and 0.72), MOD (r = 0.81 and 0.70) and RT-3DE (r = 0.94 and 0.82) correlated with MDCTA for LAV_max and LAV_min, respectively (all p < 0.05). Biases for LAV_max (-0.96 mL, 95% LoA: -5.6 to 3.7) and LAV_min (-0.67 mL, 95% LoA: -5.4 - 4.1) were minimal with RT-3DE, reflecting a slight underestimation. Conversely, MOD (LAV_maxbias = 3.19 mL, 95% LoA: -5.7 - 12.1; LAV_minbias = 1.96 mL, 95% LoA: -4.6 - 8.5) and ALM (LAV_maxbias = 4.05, 95% LoA: -5.7 - 13.8; LAV_minbias = 2.80 mL, 95% LoA: -3.9 - 9.5) suggested LAV overestimation. Intraobserver and interobserver variability were adequate.

CONCLUSIONS

Real-time three-dimensional echocardiography is a non-invasive, accurate and feasible method with superior accuracy to two-dimensional methods.

Two dimensional and real-time three dimensional ultrasound measurements of left ventricular diastolic function after marathon running: results from a substudy of the BeMaGIC trial

Strenuous exercise results in transient but minor alterations in left ventricular diastolic function (LVDF). The aim of this study is to describe and interpret the kinetics of the well-established 2D parameters of diastolic function and the novel and very sensitive 3D parameters before/after a marathon race. LVDF was evaluated by transthoracic echocardiography (TEE) in 212 healthy male [aged 42 (36-49) years)] marathon runners (all Be-MaGIC-study) in the week prior to (V1), immediately after (V2), 24 h after (V3) and 72 h after (V4) a marathon race. Real time three-dimensional echocardiography (RT3DE) included maximal and minimal left atrium (LA) volume, total LA ejection fraction (Total-EF), total LA stroke volume (Total-SV), true ejection fraction (True-EF) and atrial stroke volume (ASV). After adjustment for possible confounders (heart rate and systolic blood pressure), 2D Parameters of left ventricular inflow (E/A-ratio) decreased from pre- to immediately post-race (- 0.3 ± 0.06, p < 0.001) and returned to baseline within 24 h. [Formula: see text]-ratio remained unchanged directly post-race, but was significantly increased during follow-up of 24 and 72 h. 3D LA V_min was increased immediately postrace and in the 24 h follow-up, LA V_max was increased immediately post-race and in the follow-up of 24 and 72 h. During follow-up of 72 h, but not immediately postrace, TrueEF and ASV were significantly increased. Both techniques revealed acute and prolonged alterations of diastolic LV function. Considering all parameters, the recovery of diastolic LV after a marathon seems to take longer than previously assumed.Trial registration ClinicalTrials.gov ID: NCT00933218.

Prognostic value of echocardiographic indices of left atrial morphology and function in dogs with myxomatous mitral valve disease

Background

The prognostic relevance of left atrial (LA) morphological and functional variables, including those derived from speckle tracking echocardiography (STE), has been little investigated in veterinary medicine.

Objectives

To assess the prognostic value of several echocardiographic variables, with a focus on LA morphological and functional variables in dogs with myxomatous mitral valve disease (MMVD).

Animals

One‐hundred and fifteen dogs of different breeds with MMVD.

Methods

Prospective cohort study. Conventional morphologic and echo‐Doppler variables, LA areas and volumes, and STE‐based LA strain analysis were performed in all dogs. A survival analysis was performed to test for the best echocardiographic predictors of cardiac‐related death.

Results

Most of the tested variables, including all LA STE‐derived variables were univariate predictors of cardiac death in Cox proportional hazard analysis. Because of strong correlation between many variables, only left atrium to aorta ratio (LA/Ao > 1.7), mitral valve E wave velocity (MV E vel > 1.3 m/s), LA maximal volume (LAVmax > 3.53 mL/kg), peak atrial longitudinal strain (PALS < 30%), and contraction strain index (CSI per 1% increase) were entered in the univariate analysis, and all were predictors of cardiac death. However, only the MV E vel (hazard ratio [HR], 4.45; confidence interval [CI], 1.76‐11.24; P < .001) and LAVmax (HR, 2.32; CI, 1.10‐4.89; P = .024) remained statistically significant in the multivariable analysis.

Conclusions and Clinical Importance

The assessment of LA dimension and function provides useful prognostic information in dogs with MMVD. Considering all the LA variables, LAVmax appears the strongest predictor of cardiac death, being superior to LA/Ao and STE‐derived variables.

Evaluation of left atrial function via two-dimensional speckle-tracking echocardiography in patients with coronary artery ectasia

BACKGROUND

Coronary artery ectasia (CAE) is a segmental dilation of an epicardial coronary artery. Our aim was to evaluate the left atrial (LA) function in patients with CAE.

METHODS

Twenty-seven consecutive patients with CAE and 33 subjects without significant coronary artery disease were included in our study. LA function was evaluated with two-dimensional speckle-tracking echocardiography (2DSTE).

RESULTS

The systolic, early diastolic and late diastolic strains and strain rates were not statistically significantly different between the two groups.

CONCLUSIONS

Our findings demonstrated that LA function may not be affected by CAE when assessed with 2DSTE. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:231-237, 2017.

Assessment of Left Atrial Deformation and Function by 2-Dimensional Speckle Tracking Echocardiography in Healthy Dogs and Dogs With Myxomatous Mitral Valve Disease

Background

The assessment of left atrial (LA) function by 2‐dimensional speckle tracking echocardiography (STE) holds important clinical implications in human medicine. Few similar data are available in dogs.

Objectives

To assess LA function by STE in dogs with and without myxomatous mitral valve disease (MMVD), analyzing LA areas, systolic function, and strain.

Animals

One hundred and fifty dogs were divided according to the American College of Veterinary Internal Medicine classification of heart failure: 23 dogs in class A, 52 in class B1, 36 in class B2, and 39 in class C + D.

Methods

Prospective observational study. Conventional morphologic and Doppler variables, LA areas, and STE‐based LA strain analysis were performed in all dogs and results were compared among groups. Correlation analysis was carried out between LA STE variables and other echocardiographic variables.

Results

Variability study showed good reproducibility for all the tested variables (coefficient of variation <16%). Left atrial areas, fractional area change, peak atrial longitudinal strain (PALS), peak atrial contraction strain, and contraction strain index (CSI) differed significantly between groups B2 and C + D and all the other groups (overall P < .001), whereas only PALS differed between groups B1 and A (P = .01). Left atrial areas increased with progression of the disease, whereas LA functional parameters decreased. Only CSI increased nonsignificantly from group A to group B1 and then progressively decreased. Thirty‐one significant correlations (P < .001, r > .3) were found between conventional left heart echocardiographic variables and LA areas and strain variables.

Conclusions and Clinical Importance

Left atrial STE analysis provides useful information on atrial function in the dog, highlighting a progressive decline in atrial function with worsening of MMVD.

Is Left Atrial Function Affected by Coronary Slow Flow? A Two-dimensional Speckle-Tracking Echocardiographic Study

Background:

The coronary slow flow phenomenon (CSFP) is the slow passage of the angiographic contrast agent to the distal portion of the coronary artery in the absence of significant stenosis. We evaluated the left atrial (LA) function in patients with the CSFP using two-dimensional speckle-tracking echocardiography (2DSTE).

Methods:

The LA function was compared through 2DSTE between 36 patients with the CSFP and 36 participants with a normal coronary flow. The two groups were matched for age, sex, hypertension, diabetes mellitus, and the left ventricular function.

Results:

There were no statistically significant differences between the CSFP group and the control group regarding longitudinal systolic strain, early and late diastolic strains, and the strain rate of the LA myocardium.

Conclusions:

The LA function as evaluated with 2DSTE was not different between the CSFP group and the normal coronary flow group when they were matched for age, sex, hypertension, diabetes, and the left ventricular function.

Left Atrial Contractility in Ischemic Heart Disease Patients with Left Ventricular Systolic Dysfunction

Background:

Left atrial (LA) active emptying plays an important role in left ventricular (LV) filling. It not only depends on LA preload but also on LA contractility. Our aim was to assess LA wall contraction velocity (LAWV) and its relation to each of LA active stroke volume index (LAASVI) and LA active emptying fraction (LAAEF) as markers of LA active emptying in patients with ischemic heart disease (IHD) and impaired LV systolic function.

Methods:

We studied 50 consecutive patients with stable IHD and LV ejection fraction <45% and 50 healthy controls. Standard echocardiography assessed: Biplane LV volumes and ejection fraction, trans-mitral Doppler E and A wave velocities and E/A ratio, indexed biplane LA volumes pre- and post-atrial contraction, LAASVI and LAAEF. LAWV was measured by tissue Doppler imaging.

Results:

Trans-mitral Doppler A velocity was lower in the study group 60.64 ± 20.6 vs 72.46 ± 17.13 cm/s (P = 0.002). Accordingly, E/A ratio was higher in the study group 1.32 ± 0.78 vs 0.92 ± 0.3 (P < 0.0001). Indexed biplane LAV-pre atrial contraction was larger in the study group 23.61 ± 3.8 vs 17.16 ± 3.57mL/m² (P < 0.0001). Indexed biplane LAV-post atrial contraction was larger in the study group 16.22 ± 4.14 vs 13.19 ± 3.56mL/m² (P=0.0002). Accordingly, biplane LAASVI was higher in the study 53 group 7.9 ± 1.26 vs 3.96 ± 0.63 mL/m² (P < 0.0001). LAAEF was larger in the study group 32.37 ± 8.89 vs 24.31 ± 7.12% (P < 0.0001). LAWV was lower in the study group 6.78 ± 0.51 vs 10.58 ± 0.67 cm/sec (P < 0.0001).

Conclusion:

In patients with IHD and impaired LV systolic function, LA wall contractility is reduced. However, LAASVI and LAAEF are enhanced.

Evaluation of left atrial function by speckle tracking echocardiography in patients with systemic lupus erythematosus

Left atrial (LA) function plays a key role in maintaining optimal cardiac output. Left ventricular diastolic dysfunction (LVDD) has been reported in systemic lupus erythematosus (SLE), but whether LA functional abnormalities also occur in patients with SLE is unknown. Toward this aim we evaluated left atrial function and volume by strain and strain rate derived from speckle tracking echocardiography (STE) and their associations with LVDD. Sixty SLE patients were compared with age- and gender-matched normal controls. The LA strain (S) and strain rate (SR) during systole, early diastole and late diastole (SRs, SRe and SRa, respectively) were measured by STE. The LA volume index (LAVI), traditional parameters of LA and left ventricular diastolic function also were analysed. Global strain and positive SRe were significantly reduced in the SLE group compared with the control group (26.2% ± 9.5% vs 32.5% ± 9.8% and −2.4 ± 1.0 s−1 vs −3.1 ± 1.2 s−1, both p < 0.05). The SRs in the SLE and control groups were not significantly different (2.1 ± 0.7 s−1 vs 2.4 ± 0.8 s−1, p = 0.2). The positive SRa was increased in the SLE group compared with the control group (−2.1 ± 0.8 s−1 vs −1.6 ± 0.5 s−1, p < 0.05) and the LAVI was larger in the SLE group than in the control group (32.4 ± 8.0 vs 25.8 ± 7.1 ml/m2, p < 0.001). Patients with SLE exhibiting varying grades of LVDD displayed significant differences in LA parameters, including LAVI, SRs, SRe and SRa (all p < 0.05). Multivariate linear analysis additionally revealed that SLICC/ACR damage index (SDI) was independently and inversely associated with global strain, SRs and positive SRe. LA functions were changed in SLE patients, demonstrating impairment in conduit function, decrease in storage function and increase in pump function. Meanwhile, the magnitude of this impairment was predictively associated with the severity of LVDD. The results from this study demonstrate that STE is capable of detecting various aspects of LA functional impairment during SLE progression, and should be further explored as a diagnostic tool for improving the outcomes of SLE patients.

Left atrial structure and functional quantitation using cardiovascular magnetic resonance and multimodality tissue tracking: validation and reproducibility assessment

BACKGROUND

Left atrium (LA) strain, volume and function are important markers of cardiovascular disease and myocardial impairment. We aimed to assess the accuracy of LA biplane volume and function measured by Multimodality Tissue Tracking (MTT). Also we assessed the inter-study reproducibility for cardiovascular magnetic resonance (CMR) derived LA volume and function parameters.

METHODS

Thirty subjects (mean age: 71.3 ± 8.7, 87% male) including twenty subjects with cardiovascular events and ten healthy subjects, with CMR were evaluated in the Multi-Ethnic Study of Atherosclerosis (MESA). LA volumes were computed by the modified biplane method from 2- and 4-chamber projections and the Simpson's method from short-axis slices using both methods - manual and semi-automated delineation using MTT. LA total, active and passive ejection fractions were calculated. Pearson's correlation and Bland-Altman analysis were used to compare the measurements. In a second sample of 25 subjects (age: 65.7 ± 7.1, 72% males) inter study, intra and inter reader reliability analysis was performed. The intra-class correlation coefficient (ICC) was evaluated.

RESULTS

Left atrial MTT structural and functional parameters were not different from manual delineation, yet image analysis was only half as time consuming on average with MTT. Maximal volume MTT was not different between the Simpson's and Biplane methods, functional parameters, however were different. MTT allowed us to measure multiple LA parameters with good-excellent (ICC; 0.88- 0.98, p < 0.001) intra-and inter reader reproducibility and fair-good (ICC; 0.44-0.82, p < 0.05-0.001) inter study reproducibility.

CONCLUSIONS

MTT derived LA biplane volume and function is accurate and reproducible and is suited for use in longitudinal studies.

Effects of Bone Marrow Mononuclear Cells Delivered through a Graft Vessel for Patients with Previous Myocardial Infarction and Chronic Heart Failure: An Echocardiographic Study of Left Atrium Function

OBJECTIVES

The graft of stem cells to treat ischemic cardiomyopathy is popular in many clinical trials. The aim of this study was to evaluate the effectiveness of isolated coronary artery bypass graft combined with bone marrow mononuclear cells (BMMNC) delivered through the graft vessels to improve left atrium (LA) function of patients with previous myocardial infarction and chronic heart failure using echocardiography.

METHODS

Forty-two patients with previous myocardial infarction and chronic heart failure were randomly allocated to one of the two groups: coronary artery bypass graft (CABG) only (18 in CABG group) or CABG with BMMNC transplantation (24 in CABG + BMMNC group). Echocardiographic parameters were measured on two-dimensional (2D) imaging, three-dimensional imaging, 2D strain, and strain rate imaging, eight parameters were measured totally.

RESULTS

Postoperative LA global strain (LAGS) versus Preoperative LAGS were 24.875 ± 1.588% versus 14.250 ± 1.281% (P < 0.05) in CABG + BMMMNC group and 17.556 ± 1.834% versus 13.111 ± 1.479% (P < 0.05) in CABG group, LVEF was 49.083 ± 1.914% versus 36.042 ± 1.185% (P < 0.05) in CABG + BMMMNC group and 41.389 ± 2.210% versus 34.667 ± 1.369% (P < 0.05) in CABG group, and LA volume (LAV) was 15.651 ± 0.631 mL versus 23.894 ± 0.831 mL (P < 0.05) in CABG + BMMMNC group and 21.429 ± 0.707 mL versus 22.379 ± 0.959 mL (P < 0.05) in CABG group. LAGS, LVEF, and LAV were significantly improved postoperatively in both groups. The degree of the improvement was significantly different between the two groups with the CABG + BMMNC group improved more versus the group of CABG only (P < 0.05). Postoperative LVEDV and LVESV were significantly improved compared with those obtained prior to operation in CABG + BMMNC group (P < 0.05).

CONCLUSIONS

The improvement of LA function in CABG + BMMNC group is better than CABG group. 2D strain imaging is a more sensitive tool to evaluate LA function.

Cardiac function after repair of tetralogy of fallot: how are the atria performing? pilot study by cardiac magnetic resonance imaging

The atria of the heart function as reservoir, conduit, and active pump and are critical for ventricular filling and cardiac output. We sought to evaluate right (RA) and left atrial (LA) function in patients after tetralogy of Fallot (TOF) repair by using cardiovascular magnetic resonance. Twelve TOF patients, age 16.7 ± 6.1 years, weight 50.9 ± 14.9 kg, were compared to 10 healthy volunteers, age 18.8 ± 6.8 years, weight 52.3 ± 20.8 kg. Both atria and both ventricles were imaged in short-axis planes by Steady State Free Precession. Volume changes and all derived atrial functional parameters were calculated from the volume/time curves obtained after segmentation on the cine images. Blood flow across the AV valves was used to define ventricular diastolic dysfunction. TOF patients showed similar maximal RA volume compared to controls, but increased volumes at mid-diastole (p < 0.05), resulting in a decreased cyclic volume change and atrial filling fraction (p < 0.01), and a decreased passive emptying volume and fraction (p < 0.01). In patients with diastolic dysfunction, conduit volume was increased (p < 0.05), and active emptying volume and fraction tended to be increased, respectively. No significant changes were found in LA, except for a decreased passive emptying fraction (p < 0.05). RA function and particularly reservoir function are impaired in TOF patients. The RA conduit/reservoir ratio is increased and reflects the lost of the ability of the atrium to fill the ventricle by pulsatile flow.