Left Atrial Function Index Research Articles

Relationships between body dimensions, body weight, age, gender, breed and echocardiographic dimensions in young endurance horses.

BackgroundThe heart’s physiological adaptation to aerobic training leads to an increase in heart chamber size, and is referred to as the Athlete's heart. However, heart dimensions are also related to body weight (BWT), body size, growth and (in some species) breed. There are few published data on the relationships between heart dimensions and growth or aerobic training in Arabian and Arabian-related endurance horses. Therefore the objective of the present study was to describe the influence of body dimensions (body length (BL), thoracic circumference (TC), withers height (WH)), BWT, age, gender, breed (purebred Arabians, part-bred Arabians, Anglo-Arabians, and Others) and the initiation of endurance training on echocardiographic measurements in competition-fit endurance horses aged 4 to 6 years.ResultsMost left atrial (LA) and left ventricular (LV) dimensions increased with age, whereas LA and LV functional indices did not. Although there was no gender difference for LV dimensions, females had larger LA dimensions. In terms of breed, Anglo-Arabians had the largest LV dimensions. Regression models indicated that the included explanatory factors had a weak influence on heart dimensions. Age, body dimensions, breed and gender showed the most consistent influence on LA dimensions, whereas BWT, breed and kilometres covered in competition showed the most consistent influence on LV dimensions.ConclusionThe increase in echocardiographic dimensions with age indicates on-going growth in our population of 4 to 6 year-old horses. We also observed small changes associated with the initiation of endurance training. Morphometric dimensions had a greater influence on LA dimensions, whereas LV dimensions were also influenced (albeit weakly) by parameters associated with exercise intensity. These results may therefore reflect early adaptations linked to the initiation of endurance training.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-016-0846-x) contains supplementary material, which is available to authorized users.

Association of Left Atrial Function Index With Late Atrial Fibrillation Recurrence after Catheter Ablation.

Although catheter ablation (CA) for atrial fibrillation (AF) is commonly used to improve symptoms, AF recurrence is common and new tools are needed to better inform patient selection for CA. Left atrial function index (LAFI), an echocardiographic measure of atrial mechanical function, has shown promise as a noninvasive predictor of AF. We hypothesized that LAFI would relate to AF recurrence after CA. All AF patients undergoing index CA were enrolled in a prospective institutional AF Treatment Registry between 2011 and 2014. LAFI was measured post hoc from pre-ablation clinical echocardiographic images in 168 participants. Participants were mostly male (33% female), middle-aged (60 ± 10 years), obese and had paroxysmal AF (64%). Mean LAFI was 25.9 ± 17.6. Over 12 months of follow-up, 78 participants (46%) experienced a late AF recurrence. In logistic regression analyses adjusting for factors known to be associated with AF, lower LAFI remained associated with AF recurrence after CA [OR 0.04 (0.01-0.67), P = 0.02]. LAFI discriminated AF recurrence after CA slightly better than CHADS2 (C-statistic 0.60 LAFI, 0.57 CHADS2). For participants with persistent AF, LAFI performed significantly better than CHADS2 score (C statistic = 0.79 LAFI, 0.56 CHADS2, P = 0.02). LAFI, an echocardiographic measure of atrial function, is associated with AF recurrence after CA and has improved ability to discriminate AF recurrence as compared to the CHADS-2 score, especially among persistent AF patients. Since LAFI can be calculated using standard 2D echocardiographic images, it may be a helpful tool for predicting AF recurrence.

Quantitative evaluation of left atrial volume and function by one-dimensional, two-dimensional, and three-dimensional echocardiography in a population of normal dogs

ObjectivesThe primary goal of this study was to compare left atrial (LA) volume and functional indices in a population of normal dogs using transthoracic one-dimensional M-mode, two-dimensional (2D), and three-dimensional (3D) echocardiography. AnimalsForty clinically normal dogs of various breeds were stratified into four groups based on weight. MethodsLeft atrial volume (LAV) was estimated by converting single linear measurements derived from M-mode and 2D images into volumes via the cube and sphere formulas. 2D echocardiography was employed to estimate LAV using linear measures and rectangular and ellipsoid formulas, as well as area-length and the monoplane method of disks. LAV was estimated using the biplane area-length method on 4- and 2-chamber 2D images. LAV was directly measured using 3D volume data obtained over four consecutive cardiac cycles. LAV estimates were compared amongst methods, correlated to body size, and evaluated for reproducibility. Functional indices derived from these various echocardiographic methods were compared to identify any systematic differences based on imaging modality. LA functional indices included LA ejection fraction (LAEF), total LA emptying volume, passive LA emptying volume/fraction, active LA emptying volume/fraction, and LA expansion index. ResultsThe M-mode derived estimates of LAV were significantly smaller than all 2D- and 3D-derived LAV (p<0.0001). The left-sided 3D LAV had the highest correlation with body weight (r2 = 0.8806) for all phases of the LA cycle with acceptable interobserver variability (CV 11%). Conclusions3D echocardiography is a feasible, non-invasive method to measure LAV in a population of normal dogs.

Echocardiographic Assessment of Left Atrial Size and Function in Warmblood Horses: Reference Intervals, Allometric Scaling, and Agreement of Different Echocardiographic Variables.

BackgroundEchocardiographic assessment of left atrial (LA) size and function in horses is not standardized.ObjectivesThe aim of this study was to establish reference intervals for echocardiographic indices of LA size and function in Warmblood horses and to provide proof of concept for allometric scaling of variables and for the clinical use of area‐based indices.AnimalsThirty‐one healthy Warmblood horses and 91 Warmblood horses with a primary diagnosis of mitral regurgitation (MR) or aortic regurgitation (AR).MethodsRetrospective study. Echocardiographic indices of LA size and function were measured and scaled to body weight (BWT). Reference intervals were calculated, the influence of BWT, age, and valvular regurgitation on LA size and function was investigated and agreement between different measurements of LA size was assessed.ResultsAllometric scaling of variables of LA size allowed for correction of differences in BWT. Indices of LA size documented LA enlargement with moderate and severe MR and AR, whereas most indices of LA mechanical function were not significantly altered by valvular regurgitation. Different indices of LA size were in fair to good agreement but still lead to discordant conclusions with regard to assessment of LA enlargement in individual horses.Conclusions and Clinical ImportanceAllometric scaling of echocardiographic variables of LA size is advised to correct for differences in BWT among Warmblood horses. Assessment of LA dimensions should be based on an integrative approach combining subjective evaluation and assessment of multiple measurements, including area‐based variables. The clinical relevance of indices of LA mechanical function remains unclear when used in horses with mitral or aortic regurgitation.

GW26-e3524 Value of the left atrial function index for assessing left atrial function in patients with atrial fibrillation

GW26-e3524 Value of the left atrial function index for assessing left atrial function in patients with atrial fibrillation

Prediction of improvement in left atrial function index after catheter ablation for atrial fibrillation.

Although left atrial function index is reportedly a possible predictor of hospitalization for heart failure and of stroke irrespective of the presence or not of atrial fibrillation (AF), the effects of catheter ablation on left atrial function index have not yet been reported. We performed catheter ablation on 55 patients (age 56.6 ± 9.6years; 44 men; 30 with paroxysmal and 25 with persistent, long-standing AF) and evaluated them by transthoracic echocardiography preoperatively and 3monthly for 12-24months after catheter ablation. We then compared clinical characteristics and echocardiographic variables before catheter ablation between two groups: the 42 subjects with the most recent left atrial function index <30 and the 13 in which it was ≥30. Left atrial function index improved after catheter ablation in both groups, plateauing 6months after the procedure. Univariate analysis showed statistically significant differences in the prevalence of chronic AF and left atrial emptying fraction, diameter, and maximum and minimum volume (prevalence of chronic AF, p < 0.05; others, p < 0.01) between the groups. Multivariate analysis showed that only maximum left atrial volume predicts left atrial function index after catheter ablation (p < 0.05). In addition, we used ROC analysis to calculate a cutoff value for LA maximum volume as a good predictor and found that a good cutoff value was 63.5mL, the sensitivity and specificity being 0.75 and 0.75, respectively. Catheter ablation improves left atrial function index. However, in patients with left atrial maximum volume of over 63.5mL on echocardiography, the index did not recover to within the normal range after catheter ablation.

Effects of various cardiovascular drugs on indices obtained with two-dimensional speckle tracking echocardiography of the left atrium and time-left atrial area curve analysis in healthy dogs.

To evaluate the effects of dobutamine, esmolol, milrinone, and phenylephrine on left atrial phasic function of healthy dogs. 9 healthy Beagles. Following sedation with propofol on each of 4 experimental days, dogs were administered a constant rate infusion of dobutamine (5 μg/kg/min), esmolol (500 μg/kg/min), milrinone (25 μg/kg, IV bolus, followed by 0.5 μg/kg/min), or phenylephrine (2 μg/kg/min). There was at least a 14-day interval between experimental days. Each drug was administered to 6 dogs. Conventional and 2-D speckle tracking echocardiography were performed before (baseline) and after administration of the cardiovascular drug, and time-left atrial area curves were derived to calculate indices for left atrial reservoir, conduit, and booster pump functions (left atrial phasic function) and left ventricular contractility and lusitropy. Compared with baseline values, indices for left atrial reservoir and booster pump functions and left ventricular contractility and lusitropy were significantly increased following dobutamine administration; indices for left atrial phasic function and left ventricular lusitropy were changed insignificantly, and indices for left ventricular contractility were significantly impaired following esmolol administration; indices for left atrial phasic function and left ventricular relaxation were changed insignificantly, and indices for left ventricular systolic function were significantly augmented following milrinone administration; and indices for left atrial phasic function and left ventricular lusitropy were changed insignificantly, and indices of ventricular contractility were significantly impaired following phenylephrine administration. Results indicated that, following administration of dobutamine, esmolol, milrinone, or phenylephrine to healthy dogs, left atrial phasic function indices were fairly stable and did not parallel changes in left ventricular function indices.

The role of cardiac sympathetic innervation and skin thermoreceptors on cardiac responses during heat stress.

The mechanism(s) for the changes in cardiac function during heat stress remain unknown. This study tested two unique hypotheses. First, sympathetic innervation to the heart is required for increases in cardiac systolic function during heat stress. This was accomplished by comparing responses during heat stress between paraplegics versus tetraplegics, with tetraplegics having reduced/absent cardiac sympathetic innervation. Second, stimulation of skin thermoreceptors contributes to cardiovascular adjustments that occur during heat stress in humans. This was accomplished by comparing responses during leg only heating between paraplegic versus able-bodied individuals. Nine healthy able-bodied, nine paraplegics, and eight tetraplegics participated in this study. Lower body (i.e., nonsensed area for para/tetraplegics) was heated until esophageal temperature had increased by ~1.0°C. Echocardiographic indexes of diastolic and systolic function were performed before and at the end of heat stress. The heat stress increased cardiac output in all groups, but the magnitude of this increase was attenuated in the tetraplegics relative to the able-bodied (1.3 ± 0.4 vs. 2.3 ± 1.0 l/min; P < 0.05). Diastolic function was maintained in all groups. Indexes of left atrial and ventricular systolic function were enhanced in the able-bodied, but did not change in tetraplegics, while these changes in paraplegics were attenuated relative to the able-bodied. These data suggest that the cardiac sympathetic innervation is required to achieve normal increases in cardiac systolic function during heat stress but not required to maintain diastolic function during this exposure. Second, elevated systolic function during heat stress primarily occurs as a result of increases in internal temperature, although stimulation of skin thermoreceptors may contribute.

Relationship of ischemic times and left atrial volume and function in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention.

Little is known about the impact of duration of ischemia on left atrial (LA) volumes and function during acute phase of myocardial infarction. We investigated the relationship of ischemic times, echocardiographic indices of diastolic function and LA volumes in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). A total of 433 consecutive STEMI patients underwent echocardiographic examination within 48 h of primary PCI, including the measurement of LA volumes and the ratio of mitral peak velocity of early filling to early diastolic mitral annular velocity (E/e'). Time intervals from onset of chest pain to hospital admission and reperfusion were collected and magnitude of Troponin I release was used to assess infarct size. Patients with LA volume index (LAVI) ≥28 ml/m(2) had longer total ischemic time (410 ± 347 vs. 303 ± 314 min, p = 0.007) and higher E/e' ratio (15 ± 5 vs. 10 ± 3, p < 0.001) than those with LAVI <28 ml/m(2), while the indices of LA function were similar between the study groups (p > 0.05, for all). Significant correlation was found between E/e' and LA volumes at all stages of LA filling and contraction (r = 0.363-0.434; p < 0.001, for all) while total ischemic time along with E/e' and restrictive filling pattern remained independent predictor of LA enlargement. Increased LA volume is associated with longer ischemic times and may be a sensitive marker of increased left ventricular filling pressures in STEMI patients treated with primary PCI.

Associations of electrocardiographic P-wave characteristics with left atrial function, and diffuse left ventricular fibrosis defined by cardiac magnetic resonance: The PRIMERI Study.

Abnormal P-terminal force in lead V1 (PTFV1) is associated with an increased risk of heart failure, stroke, atrial fibrillation, and death. Our goal was to explore associations of left ventricular (LV) diffuse fibrosis with left atrial (LA) function and electrocardiographic (ECG) measures of LA electrical activity. Patients without atrial fibrillation (n = 91; mean age 59.5 years; 61.5% men; 65.9% white) with structural heart disease (spatial QRS-T angle ≥105° and/or Selvester QRS score ≥5 on ECG) but LV ejection fraction >35% underwent clinical evaluation, cardiac magnetic resonance, and resting ECG. LA function indices were obtained by multimodality tissue tracking using 2- and 4-chamber long-axis images. T1 mapping and late gadolinium enhancement were used to assess diffuse LV fibrosis and presence of scar. P-prime in V1 amplitude (PPaV1) and duration (PPdV1), averaged P-wave-duration, PR interval, and P-wave axis were automatically measured using 12 SLTM algorithm. PTFV1 was calculated as a product of PPaV1 and PPdV1. In linear regression after adjustment for demographic characteristics, body mass index, maximum LA volume index, presence of scar, and LV mass index, each decile increase in LV interstitial fibrosis was associated with 0.76 mV*ms increase in negative abnormal PTFV1 (95% confidence interval [CI] -1.42 to -0.09; P = .025), 15.3 ms prolongation of PPdV1 (95% CI 6.9 to 23.8; P = .001) and 5.4 ms prolongation of averaged P-duration (95% CI 0.9-10.0; P = .020). LV fibrosis did not affect LA function. PPaV1 and PTFV1 were associated with an increase in LA volumes and decrease in LA emptying fraction and LA reservoir function. LV interstitial fibrosis is associated with abnormal PTFV1, prolonged PPdV1, and P-duration, but does not affect LA function.

Evolution of Echocardiographic Dimensions with Age and Training in Young Endurance Horses

IntroductionIncreasing cardiac dimension with endurance training is well known in adult athletes. However, adaptation of the heart to training in growing Arabian type horses is less well documented.MethodsDuring the national finals for young endurance horses, standardized echocardiographic examinations were performed before the races by two experienced examiners. In 2011 left ventricle (LV) was assessed in 74 horses aged 4‐years (18), 5‐years (33) and 6‐years (23). In 2012 left atrial (LA) dimensions and the great heart vessels were measured in 122 horses aged 4‐years (32), 5‐years (40) and 6‐years (50). Data were normally distributed; age groups and gender were compared by one‐way ANOVA (Holm‐Sidak test for multiple comparisons, significance P&lt;0.05); relationships between echocardiographic dimensions and body weight (BWT) were assessed by linear regressions.ResultsBWT was highest in 5‐year old horses. LV dimensions increased with age, but for most measurements the difference was significant only for the group of 6‐year old horses. The stroke volume (SV) increased (P = 0.0016) and the heart rate decreased (P = 0.06) with increasing age, leading to a constant cardiac output in all age groups. There was a weak relationship between BWT and SV. Two dimensional LA measurements increased between 4 and 5 years but remained constant between 5 and 6 years. LA area measurements and LA functional indices showed no evolution between the groups. Aortic dimension increased with age but pulmonary artery dimension showed no such increase. No influence of gender on echocardiographic dimensions and function could be found.ConclusionsGreat heart vessels, LA and LV dimensions showed different growth patterns between 4 and 6 years of age.Ethical Animal ResearchProcedures were approved by the Ethics Committee for the Alfort Veterinary School and the University of Paris‐Est under number 12/07/11‐1; owner informed consent was obtained. Sources of funding: National Studs (IFCE), The Eperon Funds and the Arabian Horse Association (ACA). Competing interests: none.

Relation of Left Atrial Dysfunction to Ischemic Stroke in Patients With Coronary Heart Disease (from the Heart and Soul Study)

This study sought to determine whether left atrial (LA) dysfunction independently predicts ischemic stroke. Atrial fibrillation (AF) impairs LA function and is associated with ischemic stroke. However, ischemic stroke frequently occurs in patients without known AF. The direct relation between LA function and risk of ischemic stroke is unknown. We performed transthoracic echocardiography at rest in 983 subjects with stable coronary heart disease. To quantify LA dysfunction, we used the left atrial function index (LAFI), a validated formula incorporating LA volumes at end-atrial systole and diastole. Cox proportional hazards models were used to evaluate the association between LAFI and ischemic stroke or transient ischemic attack (TIA). Over a mean follow-up of 7.1 years, 58 study participants (5.9%) experienced an ischemic stroke or TIA. In patients without known baseline AF or warfarin therapy (n = 893), participants in the lowest quintile of LAFI had >3 times the risk of ischemic stroke or TIA (hazard ratio 3.3, 95% confidence interval 1.1 to 9.7, p = 0.03) compared with those in the highest quintile. For each standard deviation (18.8 U) decrease in LAFI, the hazard of ischemic stroke or TIA increased by 50% (hazard ratio 1.5, 95% confidence interval 1.0 to 2.1, p = 0.04). Among measured echocardiographic indexes of LA function, including LA volume, LAFI was the strongest predictor of ischemic stroke or TIA. In conclusion, LA dysfunction is an independent risk factor for stroke or TIA, even in patients without baseline AF.

EVALUATION OF ATRIAL CONTRACTILE FUNCTION DISORDERS AND FIBROSIS AS PREDICTORS OF CHRONIC HEART FAILURE

Chronic heart failure (CHF) is a major health problem in many countries now, and the cost of hospitalization is high. Early detection of atrial dysfunction, relationships between onset of symptoms and dysfunction of the atria, as well as their role in the development of systolic and diastolic heart failure is important. Interest in the assessment of left atrial transthoracic echocardiography with calculation of left atrial function index (LAFI) fraction and assessment of myocardial fibrosis with special software packages takes place lately. The search for ways to develop non-invasive methods for determining the fraction of atrial fibrosis and dysfunction is now underway. Detection of the most sensitive and specific methods will help to diagnose the initial manifestation of CHF and find an individualized approach to the treatment of each patient.

Left Atrial Function Predicts Heart Failure Events in Patients With Newly Diagnosed Left Ventricular Systolic Heart Failure During Short-Term Follow-Up

We assessed the effect of left atrial (LA) function index, LA ejection fraction, LA kinetic energy, and maximal LA volume on 6 months clinical outcome in patients with newly diagnosed systolic heart failure (HF). During a 36-month period, 179 consecutive patients (17% female, mean age 63 ± 14 years) were enrolled. During the follow-up, 46 patients had an event (32% event rate; 15 were fatal). Those with an adverse event were older, had lower creatinine clearance, advanced New York Heart Association stage, higher prevalence of ischemic HF, and lower values for right ventricle systolic wave in the tissue Doppler imaging evaluation, compared with those without an event. Multivariate analysis revealed that LA function and ischemic etiology of HF were the most significant prognostic indicators after index hospitalization. This study reveals the important role of LA function for the short-term prognosis of patients with newly diagnosed systolic HF in sinus rhythm.

Left Atrial Function by Two-Dimensional Speckle-Tracking Echocardiography in Patients with Severe Organic Mitral Regurgitation: Association with Guidelines-Based Surgical Indication and Postoperative (Long-Term) Survival

Left atrial (LA) mechanics in patients with severe mitral regurgitation (MR) remain largely unexplored. The aim of the present evaluation was to assess the effect of severe MR on LA function, its potential relation with conventional surgical indications, and long-term postoperative survival. Two-dimensional speckle-tracking strain and volumetric indices of LA reservoir, conduit, and contractile function were assessed in 121 patients with severe MR and 70 controls. Patients were divided according to the presence (n = 46) or absence (n = 75) of one or more guidelines-based criteria for mitral surgery (symptoms, left ventricular ejection fraction ≤ 60%, left ventricular end-systolic diameter ≥ 40 mm, atrial fibrillation, or systolic pulmonary arterial pressure >50 mm Hg). In patients with severe MR compared with controls, significant LA reservoir and contractile dysfunction was observed, which was more pronounced in patients with mitral surgery indication (P < .05 for all strain and volumetric indices). Of all indices of LA function, LA reservoir strain was an independent predictor (odds ratio, 0.88; 95% confidence interval, 0.82-0.94; P < .001) and had the highest accuracy to identify patients with indications for mitral surgery (area under the receiver operating characteristic curve, 0.8; 95% confidence interval, 0.72-0.87). A total of 117 patients underwent mitral valve surgery. Patients with LA reservoir strain ≤24% showed worse survival at a median of 6.4 years (interquartile range, 4.7-8.7 years) after mitral surgery (P = .02), regardless the symptomatic status before surgery. LA reservoir strain, on top of mitral surgery indications, provided incremental predictive value for postoperative survival. Impaired LA reservoir strain in patients with severe organic MR relates to long-term survival after mitral valve surgery, independently of and incremental to current guidelines-based indications for mitral surgery.

Atrial natriuretic peptide and cardiac troponin I concentrations in healthy Warmblood horses and in Warmblood horses with mitral regurgitation at rest and after exercise

ObjectiveAtrial natriuretic peptide (ANP) and cardiac troponin I (cTnI) serve as biomarkers for increased cardiac pressure/volume loading and for myocardial stress or damage. The objective was to describe the time course of plasma ANP concentrations (CpANP) and plasma cTnI concentrations (CpcTnI) in horses with mitral regurgitation (MR) compared to healthy horses at rest and after exercise, and to describe the relationship of CpANP with cardiac dimensions and intracardiac pressures. Animals15 healthy Warmblood horses and 7 Warmblood horses with MR. MethodsCardiac dimensions at rest were measured using echocardiography. All horses underwent standardized treadmill exercise. Biomarker concentrations and intracardiac pressures were measured at rest and after exercise. Hypotheses were tested using statistical methods. The level of significance was P < 0.05. ResultsHorses with MR showed increased left atrial (LA) and left ventricular (LV) dimensions but similar exercise capacity compared to healthy horses. Pulmonary capillary wedge pressures (PCWP) and CpANP increased with exercise. Horses with MR had higher PCWP and higher CpANP at rest and after exercise compared to healthy horses, with the maximum difference in CpANP reached 10 min after exercise. CpANP was significantly related to PCWP and – although inconsistently and only in healthy horses – to echocardiographic indices of LA and LV size and function. CpcTnI was low throughout the study in both groups. ConclusionsCpANP is increased in horses with MR and is related to LA pressures and to left heart dimensions. MR is not necessarily associated with exercise intolerance and exercise-induced myocardial stress or damage.

Speckle-tracking strain of the left atrium: a transoesophageal echocardiographic validation study

The aims of this study were (1) to evaluate the relationship between novel two-dimensional transthoracic indices of left atrial (LA) mechanical function (speckle-tracking- and tissue Doppler-derived parameters), conventional indices (A-wave peak velocity and velocity-time integral, and A' velocity), and transoesophageal echocardiographic parameters (LA appendage emptying velocity and spontaneous echocardiographic contrast); and (2) to assess to clinical feasibility of these novel transthoracic echocardiographic indices. Transthoracic echocardiography was performed immediately prior to or following clinically indicated transoesophageal echocardiography in 100 individuals. Longitudinal reservoir LA strain, and reservoir, conduit, and atrial contractile strain rate were measured by both speckle-tracking and tissue Doppler approaches. Inter- and intra-observer variability in 20 randomly selected cases was evaluated by the Bland-Altman technique. The time required per analysis for these novel transthoracic echocardiographic indices was recorded. In relation to LA appendage emptying velocity, the respective absolute r-values for speckle-tracking reservoir strain, and reservoir, conduit, and atrial contractile strain rate were 0.53 (P < 0.001), 0.40 (P < 0.001), 0.21 (P = 0.05), and 0.61 (P < 0.001). The absolute r-values for tissue Doppler reservoir strain, and reservoir, conduit, and atrial contractile strain rate were 0.57 (P < 0.005), 0.53 (P < 0.001), 0.022 (P = 0.8), and 0.46 (P < 0.001), respectively. In contrast, the r-values for A-wave peak velocity and velocity-time integral, and A' velocity were 0.20 (P = 0.01), 0.26 (P = 0.05), and 0.35 (P = 0.007), respectively. Speckle-tracking-derived parameters achieved the greatest area-under-the-receiver-operating characteristic curve in the identification of moderate-severe LA spontaneous echocardigraphic contrast and were more rapidly measured (P < 0.001), while exhibiting similar reproducibility to tissue Doppler-derived measures. Assessment of LA mechanical function using speckle-tracking echocardiography is a valid approach compared with transoesophageal echocardiography, and is clinically feasible.

ASSESSMENT OF THE LEFT ATRIAL FUNCTION INDEX BY ECHOCARDIOGRAPHY IN THE EVALUATION OF LEFT HEART FUNCTION IN PATIENTS WITH ESSENTIAL HYPERTENSION

ObjectivesTo evaluate the left atrial function with the left atrial function index in patients with essentienal hypertension using echocardiography.MethodsSixty hypertensive patients and 31 normal controls were selected. The high, weight,...

Assessment of Left Atrial Function in Hypertrophic Cardiomyopathy and Athlete's Heart: A Left Atrial Myocardial Deformation Study

Hypertrophic cardiomyopathy (HCM) is a common cause of sudden death in athletes and differentiating this condition from the nonpathological "athlete's heart" remains a challenge. The development of pathological left ventricular hypertrophy (LVH) is associated with left atrial (LA) dilatation and dysfunction. LA strain and strain rate by two-dimensional (2D) speckle tracking are novel indices of LA function and might contribute to differentiate physiological from pathological LVH among athletes with underdiagnosed HCM. We evaluated 20 patients with nonobstructive HCM, 20 highly trained athletes and 20 healthy controls matched for age, gender, and body surface area. All patients underwent a transthoracic echocardiogram with evaluation of LA strain: s-wave (LASs); and strain rate: s-wave (LASRs) and a-wave (LASRa). LV mass index, LA volume index, and ejection fraction were comparable between patients with HCM and athletes. Patients with HCM had a significantly lower LASs (19 + 8% vs. 43 + 8%, P < 0.01), LASRs (0.7 + 0.2 s-1 vs. 1.6 + 0.2 s-1, P < 0.01), and LASRa (-0.8 + 0.1 s-1 vs. -1.4 + 0.3 s-1, P < 0.01) compared to athletes. Among hypertrophic subjects, independent predictors of hypertrophy related to HCM were LASs and E/é ratio. LA myocardial deformation is significantly impaired in patients with HCM compared to athletes and healthy controls. LA strain and strain rate assessed by 2D speckle tracking should be incorporated in the evaluation of trained athletes with LVH and LA dilatation.

Quantitative assessment of the left atrial myocardial deformation in patients with chronic mitral regurgitation by strain and strain rate imaging: an observational study

We evaluated regional left atrial (LA) myocardial deformations by strain (S) and strain rate (SR) imaging during LA pump, reservoir, and conduit phases in patients with chronic rheumatic mitral regurgitation (MR). This cross-sectional observational study included 42 patients with moderate-to-severe MR who had normal left ventricular (LV) function, and 36 healthy control subjects. Conventional echocardiographic data were used to calculate LV and LA dimensions, volumes and functional indices (LA ejection fraction, LA active and passive emptying fraction). Longitudinal S/SR indices of the mid and superior segments of LA walls were measured during the three LA phases. Student t-test, Mann-Whitney U test, Chi-square test and Bland-Altman analysis were used for statistical analysis. LV systolic functions were similar in the patient and control groups. LV diameters, LA diameters and LA volumes were greater in the patient group compared with the control group (p<0.05, p<0.001, and p<0.001). LA ejection fraction and LA active emptying fraction values were lower in the patient group than in the control group (56 ± 7 vs. 63 ± 5%, 33 ± 9 vs. 40 ± 4%, p<0.05 for both). During the three LA phases, longitudinal S/SR values were significantly lower in all the segments in the patient group compared with the control group (p<0.001 for S, p<0.001 and p<0.05 for SR). Regional LA longitudinal myocardial deformations are observed to be impaired during all the mechanical phases in patients with moderate-to-severe MR. Volume overload, remodeling and rheumatic effects may be responsible for the LA myocardial dysfunction in these patients.