Left Atrial Performance Research Articles

Does percutaneous left atrial appendage closure affect left atrial performance?

Abstract Background: Percutaneous left atrial appendage (LAA) occlusion may be an alternative therapy for atrial fibrillation (AF) patients with contraindication for anti-coagulation therapy. However, the influence of LAA occlusion on left atrial (LA) performance has not been studied. Objective: Our aim was to evaluate the influence of percutaneous LAA occlusion device on LA function by transthoracic echocardiography plus speckle-tracking echocardiography (STE). Methods: We included 16 patients undergoing percutaneous LAA closure with adequate echocardiographic window for the study of LA mechanics. Transthoracic echocardiography was performed before and after the procedure. LA volumes were calculated using the biplane method, and LA mechanics were assessed using STE. The analysis focused on the LA reservoir phase strain and strain rate. Results: Seventy-five percent of patients had permanent atrial fibrillation. Embolic and bleeding risk scores used were CHA2DS2-VASc [median of 4-5] and HAS-BLED [median of 2-3]. Major bleeding (62%) was the most common indication for the procedure. Percutaneous LAA closure was performed successfully in all patients, without major complications. No differences were found in maximum LA volume (44 ± 11 vs. 46 ± 13 mL/m2; p = 0.54), minimum LA volume (32 ± 8 vs. 37 ± 14 mL/m2; p = 0.09) or LA emptying fraction (26 ± 17 vs. 21 ± 14%; p = 0.33) before and after the procedure. Similarly, no differences were noted in left atrial strain (13.7 ± 11.1 vs. 13.0 ± 8.8%; p = 0.63) or strain rate (1.06 ± 0.26 vs. 1.13 ± 0.34 s-1; p = 0.38) in the reservoir phase. Conclusions: Our data suggest that percutaneous LAA closure does not affect LA reservoir function.

Mid-Term Results of Surgical Treatment of Atrial Fibrillation in Valvular Heart Disease Assesed by Speckle Tracking Echocardiography.

BackgroundAtrial fibrillation frequently affects patients with valvular heart disease. Ablation of atrial fibrillation during valvular surgery is an alternative for restoring sinus rhythm.ObjectivesThis study aimed to evaluate mid-term results of successful atrial fibrillation surgical ablation during valvular heart disease surgery, to explore left atrium post-ablation mechanics and to identify predictors of recurrence.MethodsFifty-three consecutive candidates were included. Eligibility criteria for ablation included persistent atrial fibrillation <10 years and left atrium diameter < 6.0 cm. Three months after surgery, echocardiogram, 24-hour Holter monitoring and electrocardiograms were performed in all candidates who maintained sinus rhythm (44 patients). Echo-study included left atrial deformation parameters (strain and strain rate), using 2-dimensional speckle-tracking echocardiography. Simultaneously, 30 healthy individuals (controls) were analyzed with the same protocol for left atrial performance. Significance was considered with a P value of < 0.05.ResultsAfter a mean follow up of 17 ± 2 months, 13 new post-operative cases of recurrent atrial fibrillation were identified. A total of 1,245 left atrial segments were analysed. Left atrium was severely dilated in the post-surgery group and, mechanical properties of left atrium did not recover after surgery when compared with normal values. Left atrial volume (≥ 64 mL/m2) was the only independent predictor of atrial fibrillation recurrence (p = 0.03).ConclusionsLeft atrial volume was larger in patients with atrial fibrillation recurrence and emerges as the main predictor of recurrences, thereby improving the selection of candidates for this therapy; however, no differences were found regarding myocardial deformation parameters. Despite electrical maintenance of sinus rhythm, left atrium mechanics did not recover after atrial fibrillation ablation performed during valvular heart disease surgery.

Left Atrial Performance in the Course of Hypertrophic Cardiomyopathy: Relation to Left Ventricular Hypertrophy and Fibrosis.

Hypertrophic cardiomyopathy (HCM) is associated with left atrial (LA) functional abnormalities. The determinants and the degree of LA dysfunction in the course of HCM are not fully understood. We aimed to characterize LA mechanics in HCM, according to the extent of left ventricular (LV) hypertrophy and fibrosis. Seventy-three HCM patients and 23 age- and sex-matched controls underwent cardiovascular magnetic resonance imaging including late gadolinium enhancement (LGE). LA reservoir, conduit, and contractile functions were quantified by fractional volume changes and cardiovascular magnetic resonance feature-tracking-derived strain and strain rate. In multivariable regression, LA mechanics were associated with the extent of LV LGE (P = 0.033 to P < 0.001), but not with the LV mass extent or maximum wall thickness (P = 0.108 to P = 0.964). Left atrial function decreased according to the increase in extent of LV fibrosis (non-LGE; mild LGE ≤ 10%; intermediate LGE 11%-19%; severe LGE ≥ 20%). Compared with healthy controls, LA conduit function was impaired in HCM with no LGE already (LA emptying fraction conduit: 32% ± 7% vs 26 ± 14, P = 0.037). Conversely, LA contractile booster pump function was impaired in HCM with severe LGE only (LA emptying fraction booster: 40% ± 8% vs 20% ± 10%, P < 0.001; for controls vs LGE ≥ 20%, respectively). Left atrial functional abnormalities are associated with LV fibrosis, but not with LV hypertrophy. While LA conduit function is impaired in early HCM stages as represented by mild or absent LV fibrosis, LA contractile function is impaired later in the course of disease progression as demonstrated by the presence of severe LV fibrosis only. These novel markers of LA performance may potentially proof useful for disease staging and early detection of cardiac deterioration.

Serial assessment of left atrial deformation in patients undergoing pulmonary vein isolation: a cardiovascular magnetic resonance feasibility study

Background Left atrial (LA) performance quantification using Cardiovascular Magnetic Resonance (CMR) is of growing interest. There is evidence that declined left atrial function is associated with a poorer outcome following pulmonary vein isolation (PVI) in atrial fibrillation (AF). Furthermore, the influence of PVI on left atrial performance has not yet been investigated comprehensively. This study was designed to investigate the feasibility of CMR using comprehensive myocardial feature tracking (CMR-FT) and volumetric analyses for serial investigation of atrial performance before and after PVI.

Evaluation of left atrial function by real-time 3-D echocardiography in patients with systemic lupus erythematosus.

Left atrial function plays a key role in maintaining an optimal cardiac output. Left ventricular diastolic dysfunction has been reported in systemic lupus erythematosus (SLE), but its effect on left atrial function has been largely overlooked. Our aim was to assess left atrial performance using real-time 3-D echocardiography (RT3DE) technology in patients with SLE. Our study included 102 patients with SLE without any cardiac symptoms, and 32 healthy controls. According to the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI), all subjects were classified into 3 groups: healthy controls, patients with an SDI = 0, and patients with an SDI ≥ 1. Left atrial volume indexed to body surface area was dilated in subjects with SLE, whereas the left atrial passive emptying fraction (EF) was lower. Left atrial active EF was significantly higher in the SDI = 0 group than in controls (46.4 ± 9.1% vs 30.0 ± 10.3%, p < 0.05); however, it was significantly lower in the SDI ≥ 1 group than in the SDI = 0 group (41.2 ± 9.8% vs 46.4 ± 9.1%, p < 0.05). By multivariate linear analysis, the SDI was independently and positively associated with left atrial volume index and inversely associated with left atrial total function. Our study demonstrated that left atrial mechanical function and volume are impaired in SLE, particularly in patients with an SDI ≥ 1 and disease activity. RT3DE may have better diagnostic value than traditional echo indexes in detecting subclinical cardiac dysfunction in patients with SLE.

Volatile anaesthetics and positive pressure ventilation reduce left atrial performance: a transthoracic echocardiographic study in young healthy adults

Animal and in vitro studies suggest that volatile anaesthetics affect left atrial (LA) performance. We hypothesized that human LA pump function and dimensions are altered by volatile anaesthetics in vivo. We performed transthoracic echocardiographic (TTE) measurements in 59 healthy subjects (aged 18-48 yr) undergoing minor surgery under general anaesthesia. The unpremedicated patients were randomly assigned to anaesthesia with sevoflurane, desflurane, or isoflurane. TTE examinations were performed at baseline and after induction of anaesthesia and upon placement of a laryngeal mask during spontaneous breathing. After changing to intermittent positive pressure ventilation (IPPV), an additional TTE was performed. The study focused on the velocity-time integral of late peak transmitral inflow velocity (AVTI) and maximum LA volume. We found no evidence for relevant differences in the effects of the three volatile anaesthetics. AVTI decreased significantly from 4.1 (1.2) cm at baseline to 3.2 (1.1) cm during spontaneous breathing of 1 minimum alveolar concentration of volatile anaesthetics. AVTI decreased further to 2.8 (1.0) cm after changing to IPPV. The maximum LA volume was 45.4 (18.6) cm(3) at baseline and remained unchanged during spontaneous breathing but decreased to 34.5 (16.7) cm(3) during IPPV. Other parameters of LA pump function and dimensions decreased similarly. Volatile anaesthetics reduced active LA pump function in humans in vivo. Addition of IPPV decreased LA dimensions and further reduced LA pump function. Effects in vivo were less pronounced than previously found in in vitro and animal studies. Further studies are warranted to evaluate the clinical implications of these findings. NCT0024451.

Analysis of Left Atrial Performance in Patients with Type 2 Diabetes Mellitus without Overt Cardiac Disease and Inducible Ischemia: High Prevalence of Increased Systolic Force Related to Enhanced Left Ventricular Systolic Longitudinal Function

In patients with chronic pressure overload, higher left atrial systolic force (LASF) is associated with high-risk cardiovascular (CV) phenotype, with increased left ventricular (LV) mass, concentric hypertrophy, and diastolic dysfunction. In hypertension and aortic stenosis, LASF predicts increased rate of CV events independent of traditional risk factors. Moreover, LASF is an independent predictor of heart failure in diabetic and nondiabetic patients. Limited data are available about LASF and its relationship with LV systolic function in type 2 diabetes mellitus (T2DM). We used baseline clinic and echocardiographic data from 333 patients recruited in the SHORTWAVE study evaluating LV and left atrial performance in T2DM patients without cardiac disease. LASF was calculated by Manning's method and defined high when exceeded 16 Kdynes (90th percentile of LASF found in 120 healthy subjects used as controls). Mean LASF was 15.8 Â ± 9.4 Kdynes/cm(2) and showed a close positive correlation with peak mitral annular systolic velocity (function of LV longitudinal fibers), independent of E/E', age, systolic blood pressure, heart rate, and concentric geometry (multiple R = 0.57, P < 0.0001). Such independent correlation (tested in patients with and without concomitant hypertension) was confirmed at multiple logistic regression analysis where patients were dichotomized for having high (119 = 36%) or normal LASF. High LASF is present in one third of T2DM patients without overt cardiac disease and is positively and independently related to an increased LV longitudinal shortening function, suggesting a close interaction between LV systolic and diastolic function.

研究 心筋梗塞心と“正常”心とにおける右房・左房機能の比較

研究 心筋梗塞心と“正常”心とにおける右房・左房機能の比較

Aging reduces left atrial performance during adrenergic stress in middle aged and older patients

During adrenergic stress, the influence of age on left atrial (LA) function is unknown. We hypothesized that aging decreases LA total emptying fraction (LAEF) during maximal adrenergic stress. The aim of the study was to determine the influence of aging on LA function during adrenergic stress in middle aged and older patients. We enrolled 167 middle aged and elderly participants, and measured LA and left ventricular (LV) volumes using a multi-slice three-dimensional cine white blood cardiovascular magnetic resonance (CMR) technique before and during intravenous dobutamine infused to achieve 80% of the maximum heart rate response for age. Paired sample t-test was used to detect differences in LA and LV volumes between baseline and peak dose stage of dobutamine stress CMR, and multivariable linear regression was used to identify predictors of LA function. Participants averaged 68 ± 8 years in age, 53% were men, 25% exhibited coronary artery disease, 35% had diabetes, 9% had a remote history of atrial fibrillation, 90% had hypertension, and 11% had inducible LV wall motion abnormalities indicative of ischemia during dobutamine CMR. Increasing age correlated with LA volumes (maximal and minimal) and inversely correlated with LAEF at rest and after peak adrenergic stress. Age was an independent predictor of LAEF during adrenergic stress, even after accounting for gender, LV volumes, and other co-morbidities including inducible ischemia. Age is associated with a decrease in LA function during adrenergic stress even after adjusting for co-morbidities associated with cardiovascular disease and LV function.

Effects of ivabradine on heart rate and left ventricular function in healthy cats and cats with hypertrophic cardiomyopathy

To evaluate the effects of the pacemaker funny current (I(f)) inhibitor ivabradine on heart rate (HR), left ventricular (LV) systolic and diastolic function, and left atrial performance in healthy cats and cats with hypertrophic cardiomyopathy (HCM). 6 healthy cats and 6 cats with subclinical HCM. Anesthetized cats underwent cardiac catheterization and were studied over a range of hemodynamic states induced by treatment with esmolol (200 to 400 μg/kg/min, IV), esmolol and dobutamine (5 μg/kg/min, IV), ivabradine (0.3 mg/kg, IV), and ivabradine and dobutamine. Left ventricular systolic and diastolic function, cardiac output, and left atrial function were studied via catheter-based methods and echocardiography. Treatment with ivabradine resulted in a significant reduction of HR, rate-pressure product, and LV contractile function and a significant increase in LV end-diastolic pressure, LV end-diastolic wall stress, and LV relaxation time constant (tau) in cats with HCM. Concurrent administration of ivabradine and dobutamine resulted in a significant increase of LV contractility and lusitropy, with blunted chronotropic effects of the catecholamine. Left atrial performance was not significantly altered by ivabradine in cats with HCM. Regression analysis revealed an association between maximum rate of LV pressure rise and tau in cats with HCM. Ivabradine had significant effects on several cardiovascular variables in anesthetized cats with HCM. Studies in awake cats with HCM are needed to clinically validate these findings.

Comparison of the Effects of Ivabradine and Atenolol on Heart Rate and Echocardiographic Variables of Left Heart Function in Healthy Cats

Ivabradine is a novel negative chronotropic drug used for treatment of ischemic heart disease in people. Little is known about its effects and safety in cats. Ivabradine is not inferior to atenolol with regard to clinical tolerance, heart rate (HR) reduction, and effects on cardiac function in healthy, lightly sedated cats. Ten healthy laboratory cats. Physical examination, systolic blood pressure measurement, and transthoracic echocardiography were performed in all cats at baseline and after oral administration (4 weeks each) of ivabradine (0.3 mg/kg q12h) and atenolol (6.25 mg/cat q12h; 1.0-1.7 mg/kg) in a prospective, double-blind, randomized, active-control, fully crossed study. A priori noninferiority margins for the effects of ivabradine compared with atenolol were set at 50% (f = 0.5) based on predicted clinical relevance, observer measurement variability, and in agreement with FDA guidelines. Variables were compared by use of 2-way repeated measures ANOVA. Ivabradine was clinically well tolerated with no adverse events observed. HR (ivabradine, P < .001; atenolol, P < .001; ivabradine versus atenolol, P = .721) and rate-pressure product (RPP) (ivabradine, P < .001; atenolol, P = .001; ivabradine versus atenolol, P = .847) were not different between treatments. At the dosages used, ivabradine demonstrated more favorable effects than atenolol on echocardiographic indices of left ventricular (LV) systolic and diastolic function and left atrial performance. Ivabradine is not inferior to atenolol with regard to effects on HR, RPP, LV function, left atrial performance, and clinical tolerance. Clinical studies in cats with hypertrophic cardiomyopathy are needed to validate these findings.

Effect of the Selective Cardiac Myosin Activator, Omecamtiv Mecarbil, on Left Atrial Performance in Healthy Men

Effect of the Selective Cardiac Myosin Activator, Omecamtiv Mecarbil, on Left Atrial Performance in Healthy Men

Assessment of Left Atrial Volumes and Function in Orthotopic Heart Transplant Recipients by Dual-Source CT

To compare left atrial performance with dual-source CT (DSCT) with respect to magnetic resonance imaging (MRI) in orthotopic heart transplant recipients. Twenty-nine consecutive heart transplant recipients (27 male; mean age 64.1 +/- 13 years; mean time from transplantation 122.8 +/- 69.7 months) referred for exclusion of cardiac allograft vasculopathy underwent cardiac DSCT and MRI. Standard biatrial technique was employed in 13 subjects whereas 16 were transplanted after the bicaval technique. Axial 5-mm slice-thickness DSCT datasets reconstructed in 5% steps of the cardiac cycle and axial 5-mm SSFP-MRI images were analyzed. Two blinded readers manually traced left atrial contours in random order to estimate end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF). Parameters were compared with a paired sample Student t test. Concordance correlation coefficient (CCC) was calculated to determine measurement agreement between techniques and observers. Left atrial volumes were significantly higher with cardiac DSCT (EDV: 170.9 +/- 78.1 mL; ESV: 139.5 +/- 76.6 mL) than with MRI (EDV: 158.2 +/- 72.5 mL; ESV: 124.2 +/- 68.2 mL), whereas left atrial EF was lower with DSCT (EF: 20.8% +/- 7.5% vs. 23.6% +/- 7.7%) (P < 0.05). Measurement agreement between DSCT and MRI was excellent for all parameters (CCC > or =0.82). Individuals operated with the biatrial anastomosis technique presented significantly higher left atrial volumes and lower EF compared with subjects with bicaval anastomosis. Interobserver agreement was excellent for all parameters (CCC > or =0.80). Even if DSCT slightly overestimates left atrial volumes with respect to MRI, results remain clinically valid. Bicaval surgical technique offers improved left atrial performance compared with standard biatrial anastomosis. DSCT may be used as a reliable tool to estimate left atrial parameters in orthotopic heart transplant recipients.

Left Atrial Function and Work After Surgical Ventricular Restoration in Postmyocardial Infarction Heart Failure

The purpose of the current study was to examine the effect of surgical ventricular restoration in left atrial (LA) performance and left ventricular (LV) diastolic function in patients with congestive heart failure after extensive anterior myocardial infarction. Seventeen consecutive patients (age 63 +/- 9 years, 14 male, 4 with diabetes) were studied prospectively. All patients underwent surgical ventricular restoration and concomitant coronary artery bypass surgery. LA volumes were calculated, as were peak LA kinetic energy (LAKE) and LA ejection fraction (LAEF). LV diastolic filling patterns were also assessed. Follow-up period was 1 year. LA size and volumes did not change significantly during the follow-up period. Two distinct groups of patients were identified: group A, in which LAEF and peak LAKE increased, and group B, in which LAEF and peak LAKE decreased. In both groups, the LAEF and peak LAKE appeared to increase or decrease simultaneously and this became evident from the first month after the surgery. However, 1 year after the operation, diastolic filling pattern was significantly different between the two groups. LA function showed improvement only in patients who demonstrated an improvement in indices of diastolic filling pattern. Despite improvement in clinical status and indices of LV systolic function in all patients who underwent surgical ventricular restoration for treatment of congestive heart failure as a result of LV dilatation secondary to large myocardial infarction, improvement of LA function occurs in patients with improved LV diastolic function.

652 Relationship of exercise capacity with left ventricular and atrial performance in heart failure

652 Relationship of exercise capacity with left ventricular and atrial performance in heart failure

Relationship between left ventricular geometry and left atrial size and function in patients with systemic hypertension.

Arterial hypertension determines distinct adaptive left ventricular geometric responses, which may differently affect left ventricular function and left atrial performance. In this study, the effect of left ventricular geometry on left atrial size and function, and the relationship between left atrial size and left ventricular mass were assessed in 336 patients with systemic arterial hypertension who had undergone Doppler echocardiography. Patients were classified into concentric (110 patients with concentric left ventricular geometry defined as relative wall thickness > or = 0.44) and eccentric groups (226 patients with relative wall thickness < 0.44). Comparison to the latter, the former had greater left atrial size, left atrial ejection force, left ventricular mass and lower left ventricular midwall fractional shortening. Left ventricular concentric, rather than eccentric, geometry emerged by multivariate analysis as a factor independently associated with the highest degree of left atrial ejection force. Left atrial size was positively related to left ventricular mass in the whole population (r = 0.65, SEE = 6 ml, P < 0.00001). This relationship was maintained in the subgroups with concentric (r = 0.65, SEE = 6 ml, P < 0.00001) or eccentric geometry (r = 0.59, SEE = 6 ml, P < 0.00001). Our results indicate that the relationship of left ventricular geometry to both left atrial size and ejection force in hypertensive patients is relevant. Concentric left ventricular geometry is associated with greater left atrial size and ejection force than eccentric geometry, suggesting that increased left ventricular stiffness has a greater effect in stimulating left atrial performance than left ventricular end-systolic stress. The degree of left atrial enlargement similarly depends on left ventricular mass in patients with concentric and eccentric geometry.

Comparison of left ventricular geometry and left atrial size and function in patients with aortic stenosis versus those with pure aortic regurgitation

Chronic aortic valve disease can result in distinct adaptive left ventricular (LV) geometric patterns, which has different effects on LV function and left atrial (LA) performance. In this study we assessed the effect of LV geometry on LA size and function, and we verified the relation between LA size and LV mass in patients with distinct LV overload subsets. We analyzed 183 patients with aortic valve disease who underwent a complete echocardiographic evaluation. Based on the type of valvular dysfunction, patients were classified into 2 groups: 141 patients with aortic stenosis (group AS) and 42 patients with pure aortic regurgitation (group AR). Each of these 2 groups were then divided into those with a concentric LV pattern and those with an eccentric pattern. Both LA size and LA ejection force were significantly greater in group AS than group AR, particularly in patients with a concentric LV pattern. The degree of LA enlargement depended on LV mass in the patients with a concentric LV pattern (group AS r = 0.61, p <0.00001; group AR r = 0.38, p = 0.04). In contrast, no relation was found between LA size and LV mass in the patients with an eccentric pattern, independently of the type of valve dysfunction. Our results indicate that the influence of LV geometry on LA size and function in patients with aortic valve disease is relevant. A concentric LV pattern is associated with greater LA size and higher ejection than an eccentric pattern, suggesting that chronic LV pressure overload more than volume overload has a greater effect on stimulating increases in LA performance. The degree of LA enlargement depends on LV mass in patients with a concentric LV pattern, whereas it was unpredictable in those with an eccentric LV pattern.

Evaluation of the Left Atrial Performance Using Acoustic Quantification.

In most clinical studies, evaluation of left atrial (LA) function evolved from estimation of LA size on chest radiograph, electrocardiographic P wave abnormalities, LA diameter determined at fluoroscopy or by echocardiography, LA pressure recordings, blood flow velocity with Doppler echocardiography, and measurements of LA volume based on echocardiographic, cineangiographic, radionuclide, and magnetic resonance imaging techniques. The recent development of real-time two-dimensional echocardiographic acoustic quantification (AQ) suggests that LA dimensions can be measured instantaneously to provide online assessment of its systolic and diastolic functions. By means of AQ echocardiography and simultaneous recordings of LA pressure, the LA pressure-area relation can be obtained. LA pressure-area relation consisted of two loops: the A loop, representing the LA pump function, and the V loop, representing LA reservoir and passive emptying functions. The importance of LA function has been demonstrated in congestive heart failure, atrial fibrillation, hypertension, and ischemic heart disease and during pacing or dobutamine infusion.

Assessment of Left Atrial Contractile Performance in Normal and Pathological Conditions Using Elastance

Assessment of Left Atrial Contractile Performance in Normal and Pathological Conditions Using Elastance

Assessment of left atrial contractile performance in normal and pathological conditions using elastance

Assessment of left atrial contractile performance in normal and pathological conditions using elastance