Left Atrial Contractile Function Research Articles

Left atrial strain in patients after arterial switch operation for transposition of the great arteries

Background Left atrial (LA) strain, comprising LA reservoir, conduit and contractile function could add mechanistic information of patients after arterial switch operation (ASO) for transposition of the great arteries (TGA). ASO patients might have abnormal ventriculoarterial coupling, which makes them vulnerable to left ventricle (LV) dysfunction and results in reduced exercise capacity. This explorative study aimed to evaluate the relation between LA strain, atrial size, ventricular function, and exercise data obtained by cardiopulmonary exercise testing (CPET). Methods In a cohort of 44 patients (71% male, mean age 25 ± 4 years) LA strain was measured using transthoracic speckle-tracking echocardiography. Further assessment involved standard echocardiography, CPET evaluation, and blood sampling. LA strain values were compared to normal values. Correlations were calculated. Regression analysis with all strain variables to the CPET data was performed. Results LA reservoir, conduit and contractile strain were normal in 30%, 89% and 50% of the patients, respectively. LA reservoir/contractile strain correlated to LV ejection fraction (ρ 0.310/−0.159, respectively) and LA reservoir/conduit strain correlated to the LA volume index (ρ 0.336/−0.357, respectively). None of the individual LA strain parameters were associated with the CPET variables. In multivariate regression analysis, LA contractile strain was significantly associated with the percentage of predicted maximal heart rate (β − 2.555). Conclusions These data suggest that in TGA patients after ASO repair LA strain is impaired and correlates with LA size and LV function. However, impaired LA strain wasn’t associated with the standard CPET parameters. As such, clinical significance needs to be further unravelled.

Association of diabetes and glycemic control with left atrial function: The Atherosclerosis Risk in Communities (ARIC) study

Background and aimsAlthough glycemic status is associated with impaired cardiac structure and function, less is known on left atrial (LA) function across the glycemic spectrum. We evaluated the association of diabetes and glycemic control with LA function in a community-based cohort of older adults. Methods and resultsThis cross-sectional analysis included 5075 participants from the Atherosclerosis Risk in Communities Study (mean age 75.5 years, 58 % women, and 20 % Black adults) with echocardiographic strain data for LA reservoir, conduit, and contractile function. Multivariable linear regression was used to assess associations of diabetes status and glycemic control with LA function. In participants without diabetes, we used ordinal linear regression to evaluate associations of fasting glucose and HbA1c with LA function. Compared to individuals with a normal fasting glucose, prevalent diabetes was associated with 0.68 % lower LA conduit function (95 % confidence interval (CI): 1.11 to −0.25) and prediabetes a 0.47 % reduction (95 % CI: 0.85 to −0.09) in fully adjusted analyses. Persons with diabetes and high HbA1c (HgbA1c ≥ 7 % vs <7 %) had 1.05 % lower LA conduit function (95 % CI: 1.63, −0.48). Among individuals without diagnosed diabetes, higher fasting glucose, but not HbA1c, was significantly associated with worse LA conduit function. No significant associations were observed for LA reservoir and contractile function. ConclusionsA history of diabetes, prediabetes, and higher fasting glucose levels in persons without diabetes were associated with worse LA conduit function. Corroborative research is needed in prospective cohorts as well as studies that explore underlying mechanisms.

Left atrial mechanics evaluated by two-dimensional strain analysis: alterations in essential hypertension.

Hypertension is a cardiovascular risk factor that predisposes to cardiac structural alterations namely increased left ventricular (LV) wall thickness, reduced LV compliance and diastolic dysfunction, with consequent left atrial (LA) dilation and functional impairment. In this article, we evaluated differences in left atrial structure and function using two-dimensional speckle tracking echocardiography in patients with hypertension compared with controls. This was a retrospective cross-sectional study of 208 hypertensive patients and 157 controls who underwent a comprehensive transthoracic echocardiogram. Patients with hypertension were stratified by the presence of left ventricular hypertrophy (LVH). Non-LVH hypertension patients had lower left atrial reservoir strain (LAS RES ) (34.78 ± 29.78 vs. 29.78 ± 6.08; P = 0.022) and conduit strain (LAS CD ) (19.66 ± 7.29 vs. 14.23 ± 4.59; P = 0.014) vs. controls despite similar left atrial volumes (LAV) . Left atrial contractile strain (LAS CT ) was not significantly different between non-LVH hypertension patients and controls (15.12 ± 3.77 vs. 15.56 ± 3.79; P = 0.601). Left atrial mechanical dispersion was significantly higher in the LVH group compared with the non-LVH hypertension group (42.26 ± 13.01 vs. 50.06 ± 14.95; P = 0.009). In multivariate regression analysis, LVH correlated with left atrial mechanical dispersion ( P = 0.016). An age-hypertension interaction independently correlated with LAS CT ( P < 0.001). Hypertension results in functional left atrial changes even before development of LV hypertrophy and structural left atrial changes with increased left atrial volume. We demonstrate both a likely hypertension-associated left atrial myopathy that prevents age-related compensatory increase in left atrial contractile function, and impact of LVH in hypertension on left atrial dyssynchrony.

Left Atrial Dysfunction in Apical Hypertrophic Cardiomyopathy: Assessed by Cardiovascular Magnetic Resonance Feature-tracking.

To evaluate the left atrial (LA) function in participants with apical hypertrophic cardiomyopathy (AHCM) by cardiovascular magnetic resonance feature tracking (CMR-FT). Thirty typical AHCM (TAHCM) patients, 23 subclinical AHCM (SAHCM) patients and 32 normal healthy volunteers who underwent CMR exam were retrospectively analyzed. LA reservoir, conduit, and contractile function were quantified by volumetric and CMR-FT derived strain and strain rate (SR) parameters from 2-chamber and 4-chamber cine imaging. Compared with healthy participants, both TAHCM and SAHCM patients had impaired LA reservoir function (total strain [%]: TAHCM 31.3±12.2, SAHCM 31.8±12.3, controls 40.4±10.7, P <0.01; total SR [/s]: TAHCM 1.1±0.4, SAHCM 1.1±0.5, controls 1.4 ± 0.4, P <0.01) and conduit function (passive strain [%]: TAHCM 14.4±7.6, SAHCM 16.4±8.8, controls 23.3±8.1, P <0.01; passive SR [/s]: TAHCM -0.5±0.3, SAHCM -0.6±0.3, controls -1.0±0.4, P <0.01). Regarding contraction function, although TAHCM and SAHCM patients had preserved active emptying fraction and strain (all P >0.05), patients with TAHCM had the lowest active SR value among the 3 groups ( P= 0.03). LA reservoir and conduit strain were both significantly associated with left ventricular mass index and maximal wall thickness (all P <0.05). A moderate correlation between LA passive SR and left ventricular cardiac index ( P <0.01). The LA reservoir and conduit function are predominately impaired and appeared in both SAHCM and TAHCM patients.

The loss of left atrial contractile function predicts a worse outcome in HFrEF patients.

In chronic heart failure, high intracardiac pressures induce a progressive remodeling of small pulmonary arteries up to pulmonary hypertension. At the end of left atrial conduit function, pulmonary and left heart end-systolic pressures equalization might affect left atrial systole. In this single-center prospective study, we aimed to investigate whether peak atrial contraction strain (PACS), measured by speckle tracking echocardiography, was independently associated with prognosis in heart failure with reduced ejection fraction (HFrEF). Outpatients with HFrEF and sinus rhythm referred to our echo-labs were enrolled. After clinical and echocardiographic evaluation, off-line speckle tracking echocardiography analysis was performed. Primary and secondary endpoint were cardiovascular death and heart failure hospitalization, respectively. Spline knotted survival model identified the optimal prognostic cut-off for PACS. The 152 patients were stratified based on PACS <8% (n = 76) or PACS ≥8% (n = 76). Patients with PACS <8% had lower left ventricle and left atrial reservoir strain and higher New York Heart Association (NYHA) class and left atrial volume index (LAVI). Over a mean follow-up of 3.4 ± 2 years, 117 events (51 cardiovascular death, 66 heart failure hospitalizations) were collected. By univariate and multivariate Cox analysis, PACS emerged as a strong and independent predictor of cardiovascular death and heart failure hospitalization, after adjusting for age, sex, left ventricle strain, and E/e', LAVI (HR 0.6 per 5 unit-decrease in PACS). Kaplan-Meier curves showed a sustained divergence in event-free survival rates for the two groups. The reduction of PACS significantly and independently affects cardiovascular outcome in HFrEF. Therefore, its assessment, although limited to patients with sinus rhythm, could offer additive prognostic information for HFrEF patients.

Left atrial contraction strain during a Valsalva manoeuvre:Astudy in healthy humans.

Cardiac mechanics are influenced by loading conditions as well as sympathetic tone. Left atrial (LA) contractile function assessed by two-dimensional (2D) strain has been described in the setting of controlled preload alterations; however, studies show conflicting findings about change or direction of change. We hypothesized that the controlled preload reduction and the sympathetic nervous system activation that occurs during a standardized Valsalva manoeuvre would bring about a change in LA contraction strain. Healthy young adults of both sexes were recruited. Transthoracic echocardiographic ultrasound images were collected before and during a Valsalva manoeuvre. Standard imaging windows for LA strain assessment were used and the images were copied and stored for later offline analysis. These were assessed for adequate atrial wall visualization in 2D strain assessment. Paired comparisons were carried out using Student's Ttest. Thirty-eight participants were included and there were 22 complete studies with paired pre- and during Valsalva manoeuvre. LA contraction strain at baseline was 10.5 ± 2.8% (standard deviation) and during the Valsalva manoeuvre 10.6 ± 4.6%, p = 0.86. The Valsalva manoeuvre, a combination of preload reduction and sympathetic nervous system activation, seems not to be associated with a change in LA contraction strain in healthy young individuals. LA contraction strain should be interpreted in the context of both atrial loading conditions and prevailing autonomic nervous system activity.

Left atrial contraction strain and controlled preload alterations, a study in healthy individuals

BackgroundIn order to assess left atrial contractile function in disturbed circulatory conditions, it is necessary to have a clear understanding of how it behaves in a normal resting state with changes in loading conditions. However, currently the understanding of this relationship is incomplete. We hypothesize that in healthy individuals, left atrial contraction strain and its peak strain rate are increased or decreased by increasing or decreasing preload, respectively.MethodsControlled maneuvers used to change preload included continuous positive airway pressure by mask (CPAP 20 cmH2O) for preload decrease, and passive leg raise (15 degrees angle) for preload increase. Cardiac ultrasound 4-chamber views of the left atria and left ventricle were acquired at baseline and during maneuver. Acquired images were post processed and analyzed offline. Comparisons were made using paired t-test and means with 95% confidence interval.ResultsThere were 38 participants, complete results were obtained from 23 in the CPAP maneuver and 27 in the passive leg raise maneuver. For the CPAP group, left atrial contraction strain was 11.6% (10.1 to 13.1) at baseline and 12.8% (11.0 to 14.6) during the maneuver (p = 0.16). Left atrial contraction peak strain rate was − 1.7 s− 1 (− 1.8 to − 1.5) at baseline and − 1.8 s− 1 (− 2.0 to − 1.6) during the maneuver (p = 0.29). For the passive leg raise-group, left atrial contraction strain was 10.1% (9.0 to 11.2) at baseline and 10.8% (9.4 to 12.3) during the maneuver (p = 0.28). Left atrial contraction peak strain rate was − 1.5 s− 1 (− 1.6 to − 1.4) at baseline and − 1.6 s− 1 (− 1.8 to − 1.5) during the maneuver (p = 0.29). Left atrial area, an indicator of preload, increased significantly during passive leg raise and decreased during CPAP.ConclusionIn healthy individuals, left atrial contraction strain and its peak strain rate seem to be preload-independent.Trial registrationThe study was 2018-02-19 registered at clinicaltrials.gov (NCT03436030).

The Effect of TAVR on Left Ventricular and Left Atrial Mechanics in Patients with Aortic Stenosis.

Background. Measures of adverse cardiac remodeling, left ventricular global longitudinal strain (LVGLS) and left atrial (LA) phasic function, are predictive of cardiac events in patients with severe aortic stenosis (AS). How these parameters of cardiac function change following TAVR requires further investigation. Methods. A number of 109 consecutive patients with symptomatic severe AS who were seen in the heart valve clinic between 2014 and 2019 for TAVR were included. All patients underwent echocardiographic assessment prior to and 30 days following TAVR, with LVGLS and LA phasic function evaluation using 2D speckle-tracking echocardiography. Heart failure hospitalization, and death were assessed at 12 months. Results. The mean age of the study cohort was 81 ± 7.3 years. Following TAVR, there was a significant reduction in NYHA class III/IV symptoms [89 (82%) vs. 12 (11%), p < 0.01], and median mean aortic valve gradient [44 mmHg (16) vs. 9 mmHg (7), p < 0.01]. There was no significant change in the median LVEF [62% (13) vs. 62% (6.0), p = 0.2]; however, the LVGLS significantly increased following TAVR [15 ± 3.5% vs. 18 ± 3.3%, p < 0.01]. The median LA reservoir, conduit and contractile function significantly improved following TAVR [22.0% (14.0) vs. 18.0% (14.0) p < 0.01, 8.9% (5.4) vs. 7.8% (4.8) p < 0.01, 12% (11.0) vs. 9.6% (11.0) p < 0.01, respectively]. The incidence of death or heart failure hospitalization at 12 months was low, and occurred in eight patients (7.3%). Conclusions. TAVR results in significant short-term reverse LV and LA remodeling, as shown by improvement in LV GLS and all three components of LA phasic function, despite no change in the LVEF. The findings indicate the possible utility of strain imaging for the assessment of global LV and LA function following TAVR.

Electrocardiographic diagnosis of atrial cardiomyopathy to predict atrial contractile dysfunction, thrombogenesis and adverse cardiovascular outcomes

Thromboembolism and stroke are dreaded complications in atrial fibrillation (AF). Established risk stratification models identify susceptible patients, but their discriminative properties are poor. Atrial cardiomyopathy (ACM) is associated to thromboembolism and stroke in smaller studies, but the modalities used for ACM-diagnosis (MRI and endocardial mapping) are unsuitable for widespread population screening. We aimed to investigate an ECG-based diagnosis of ACM using amplified p-wave analysis (APWA) for stratification of thromboembolic risk and cardiovascular outcome. In this case–control study, ACM-staging was performed using APWA on digital 12-lead sinus rhythm-ECGs in patients with LAA-thrombus and a propensity-score-matched control-cohort. Left atrial contractile function and thrombi were evaluated by transesophageal echocardiography (TEE). Outcome for MACCE including death was assessed using official registries and structured phone interviews. Left-atrial appendage [LAA]-thrombi and appropriate sinus rhythm-ECGs for ACM-staging were found in 109 of 4086 patients that were matched 1:1 to control patients without thrombus (218 patients in total). Both cohorts were comparable regarding cardiovascular risk factors, anticoagulants and CHA2DS2-VASC-score. ACM-stages 1 to 3 (equivalent to no, moderate and extensive ACM) were found in 63 (57.8%), 36 (33.0%) and 10 (9.2%) of patients without and 3 (2.8%), 23 (21.1%) and 83 (76.1%) of patients with LAA-thrombi. Atrial contractile function decreased from ACM-stages 1 to 3 (LAA-flow velocities 38 ± 16 cm/s, 31 ± 15 cm/s and 21 ± 12 cm/s; p < 0.0001), while the likelihood for LAA-thrombus increased (2.8%, 21.1% and 76.1%, p < 0.001). Multivariable analysis confirmed an independent odds ratio for LAA-thrombus of 24.6 (p < 0.001) per ACM-stage. Two-year survival free of stroke/TIA, hospitalization for heart failure, myocardial infarction or all-cause death was strongly reduced in ACM-stage 3 (53.8%) compared to no or moderate ACM (82.8% and 84.7%, respectively; p < 0.0001). Electrocardiographic diagnosis of ACM identifies patients with atrial contractile dysfunction and atrial thrombi at risk for adverse cardiovascular outcomes and death.

SGLT2 Inhibitor use Pre-Discharge Improves Left Atrial Reservoir and Contractile Function Following Acute Coronary Syndrome in Patients With Siabetes

Left atrial (LA) strain, a novel marker of LA function, reliably predicts diastolic dysfunction and outperforms conventional parameters. SGLT2 inhibitors can improve diastolic function in patients with type 2 diabetes (T2D) but limited data exists regarding their use in the immediate aftermath of acute coronary syndrome (ACS). We studied the effect of empagliflozin on LA strain in patients with T2D and ACS. We identified patients with ACS and T2D during hospitalisation; empagliflozin was initiated in eligible patients pre-discharge; patients not initiated on empagliflozin were the comparator group. Baseline and 3-6 month follow-up 2-dimensional echocardiograms were performed to assess LA strain. A total of 44 patients were recruited (n=22, each group). Baseline characteristics were similar (age 60.8±9.5 vs 65.1±10.4 yrs), LA volume index 32.2±9.4mL/m2 vs 35.2±11.6mL/m2, LVEF 51.1±11.3% vs 54.9±10.8%; p=NS for all. Except, HbA1c was higher in empagliflozin group (9.8±1.6% vs 6.6±0.7%, p<0.001). No difference was seen in baseline LA strain parameters between groups (reservoir 29.5% vs 30.5%, conduit 15.0% vs 12.8%, contractile 14.5% vs 17.7%; p=NS for all). LA reservoir and contractile strain increased significantly at follow-up in empagliflozin group (29.5% to 36.6%, p=0.005 and 14.5% to 17.7%, p=0.024, respectively) but remained unchanged in comparison group (30.5% to 30.5% and 17.7% to 17.0%; p=NS for both). The difference in change between groups was significant for LA reservoir and contractile strain (p=0.015 and p=0.029, respectively). LA reservoir and contractile function improve with SGLT2 inhibitor use following ACS in patients with T2DM. Larger studies are warranted to determine clinical implications.

Clinical Importance of Left Atrial Infiltration in Cardiac Transthyretin Amyloidosis

ObjectivesThe aim of this study was to characterize left atrial (LA) pathology in explanted hearts with transthyretin amyloid cardiomyopathy (ATTR-CM); LA mechanics using echocardiographic speckle-tracking in a large cohort of patients with ATTR-CM; and to study the association with mortality. BackgroundThe clinical significance of LA involvement in ATTR-CM is of great clinical interest. MethodsCongo red staining and immunohistochemistry was performed to assess the presence, type, and extent of amyloid and associated changes in 5 explanted ATTR-CM atria. Echo speckle tracking was used to assess LA reservoir, conduit, contractile function, and stiffness in 906 patients with ATTR-CM (551 wild-type (wt)-ATTR-CM; 93 T60A-ATTR-CM; 241 V122I-ATTR-CM; 21 other). ResultsThere was extensive ATTR amyloid infiltration in the 5 atria, with loss of normal architecture, vessels remodeling, capillary disruption, and subendocardial fibrosis. Echo speckle tracking in 906 patients with ATTR-CM demonstrated increased atrial stiffness (median [25th-75th quartile] 1.83 [1.15-2.92]) that remained independently associated with prognosis after adjusting for known predictors (lnLA stiff: HR: 1.23; 95% CI: 1.03-1.49; P = 0.029). There was substantial impairment of the 3 phasic functional atrial components (reservoir 8.86% [5.94%-12.97%]; conduit 6.5% [4.53%-9.28%]; contraction function 4.0% [2.29%-6.56%]). Atrial contraction was absent in 22.1% of patients whose electrocardiograms showed sinus rhythm (SR) “atrial electromechanical dissociation” (AEMD). AEMD was associated with poorer prognosis compared with patients with SR and effective mechanical contraction (P = 0.0018). AEMD conferred a similar prognosis to patients in atrial fibrillation. ConclusionsThe phenotype of ATTR-CM includes significant infiltration of the atrial walls, with progressive loss of atrial function and increased stiffness, which is a strong independent predictor of mortality. AEMD emerged as a distinctive phenotype identifying patients in SR with poor prognosis.

The Prevalence of Advanced Interatrial Block and Its Relationship to Left Atrial Function in Patients with Transthyretin Cardiac Amyloidosis.

Background: Advanced interatrial block (aIAB), which is associated with incident atrial fibrillation and stroke, occurs in the setting of blocked interatrial conduction. Atrial amyloid deposition could be a possible substrate for reduced interatrial conduction, but the prevalence of aIAB in patients with transthyretin cardiac amyloidosis (ATTR-CA) is unknown. We aimed to describe the prevalence of aIAB and its relationship to left atrial function in patients with ATTR-CA in comparison to patients with HF and left ventricular hypertrophy but no CA. Methods: The presence of aIAB was investigated among 75 patients (49 patients with ATTR-CA and 26 with HF but no CA). A comprehensive echocardiographic investigation was performed in all patients, including left atrial strain and strain rate measurements. Results: Among patients with ATTR-CA, 27% had aIAB and in patients with HF but no CA, this figure was 21%, (p = 0.78). The presence of aIAB was associated with a low strain rate during atrial contraction (<0.91 s−1) (OR: 5.2 (1.4–19.9)), even after adjusting for age and LAVi (OR: 4.5 (1.0–19.19)). Conclusions: Advanced interatrial block is common among patients with ATTR-CA, as well as in patients with heart failure and left ventricular hypertrophy but no CA. aIAB is associated with reduced left atrial contractile function.

Multichamber Dysfunction in Children and Adolescents With Severe Obesity: A Cardiac Magnetic Resonance Imaging Myocardial Strain Study.

In severe obesity, left ventricular (LV) and right ventricular (RV) remodeling and contractile dysfunction have been documented, but less is known regarding left atrial (LA) dysfunction and its association with LV/RV remodeling, especially in children. To assess the effects of severe childhood obesity on cardiac function by using multichamber strain analysis with MRI. Prospective. Forty-five children aged 7-18 years (including 20 with severe obesity, defined as a body mass index values above the 99th percentile). 5 T. Steady-state-free-precession (SSFP) images in short-axis views and longitudinal two- and four-chamber views. Cardiac strain measurements were derived from standard SSFP cine images by using a dedicated MR imaging feature tracking software. Inter- and intra-rater reliability were evaluated. Independent sample t test, Spearman's correlation coefficient, principal component analysis, Bland-Altman analysis, and intra-class correlation coefficients (ICC). A P value <0.05 was considered statistically significant. As compared to children without obesity, those with obesity showed significantly reduced LA reservoir function (22.2% ± 6.4% vs. 33.8% ± 9.0%) and contractile function (5.4% ± 3.2% vs. 13.3% ± 8.0%) as well as significantly decreased absolute values for LA longitudinal strain in reservoir and contraction phases and LA radial motion fraction in reservoir and contraction phases. Children with severe obesity showed significantly reduced absolute RV radial motion fraction (-10.6% ± 2.9% vs. -18.2% ± 2.9%) and circumferential strain (-10.6% ± 2.9% vs. -16% ± 2.5%) as well as higher LV mass index (28.7% ± 5.1% vs. 21.7 ± 4.6 g/m2 ) along with significantly reduced LV ejection fraction (56.4% ± 3.9% vs. 60% ± 4.1%), LV radial strain (56% ± 6% vs. 61.8% ± 11.3%), and longitudinal strain (-17.8% ± 1.8% vs. -20.3% ± 3.2%). Reliability was good to excellent, with ICC ranging from 79.1% to 97.7%. MR feature-tracking strain analysis revealed multichamber dysfunction in severely obese children with impaired LA reservoir and atrial contraction phases, which suggest an early loss in the compensatory ability of atrial contraction with severe obesity. 2 TECHNICAL EFFICACY STAGE: 3.

Abstract P150: Association Of Leisure Time Physical Activity (LTPA) With Left Atrial Function In Older Adults: The Atherosclerosis Risk In Communities (ARIC) Study

Introduction: Prior research indicates that higher LTPA is associated with better left ventricular (LV) diastolic function, but not with left atrial volume index (LAVI). Left atrial (LA) strain is a more sensitive marker of LA pathology. Hence, we evaluated association of LTPA with LA strain in the ARIC study, a community-based cohort study. Hypothesis: Higher LTPA is associated with better LA reservoir, conduit and contractile function. Methods: We included 4005 participants (mean age 75 years, 63% female, 21% black) with 2D echocardiographic (2DE) LA % strain data, LTPA data, and without prevalent coronary heart disease, valvular heart disease, heart failure, atrial fibrillation, and stroke at Visit 5 (V5, 2011-13). We estimated LTPA as metabolic equivalent-minutes per week from validated Baecke questionnaire and categorized it as poor, intermediate, or ideal as per AHA recommendation. We categorized change in LTPA from V3 (1993-95) to V5 as persistently poor (referent), decreasing, increasing, or persistently active. LA reservoir, conduit, and contractile % strain were measured from speckle-tracking 2DE. Linear regression was used to evaluate association of LTPA with LA function. We modeled LTPA (1) cross-sectionally at V5 as a continuous variable and (2) change from V3 to V5, as continuous and categorical variables (referent- persistently poor). Results: Higher LTPA at V5 (Table) and persistently high (vs poor) LTPA from V3 to 5 (β estimate -0.89, 95% CI -1.40, -0.38) were significantly associated with better LA conduit function after adjusting for CV risk factors, LV function, and LAVI. The same associations with LA reservoir function were no longer significant after adjusting for CV risk factors. LTPA was not associated with LA contractile function (Table). Conclusions: Consistent with LTPA’s salutary effect on LV diastolic function, higher LTPA is associated with better LA conduit function. Maintaining high LTPA from midlife to late-life may be beneficial in mitigating age-related changes in cardiac function.

Impaired left atrial reservoir and conduit strain in patients with atrial fibrillation and extensive fibrosis

Abstract Funding Acknowledgements Type of funding sources: None. Background Atrial fibrillation (AF) is associated with profound structural and functional changes in the atria. Timely interventions may decelerate and perhaps reverse this pathophysiologic process and improve clinical outcome. In this regard, detailed characterization of the atrial remodeling process, and understanding of the interplay between structural remodeling and function is essential. Purpose In the present study, we investigated the association between left atrial (LA) phasic function and the extent of LA fibrosis using advanced cardiovascular magnetic resonance (CMR) imaging techniques, including 3-dimensional (3D) late gadolinium enhancement (LGE) and Feature Tracking. Methods Patients with paroxysmal and persistent AF (n = 93) underwent CMR in sinus rhythm. LA global reservoir strain, conduit strain and contractile strain were derived from cine CMR images using Feature Tracking. The extent of LA fibrosis was assessed from 3D LGE images. Healthy volunteers underwent CMR and served as controls (n = 19). Results Significantly lower reservoir strain, conduit strain and contractile strain were found in AF patients, as compared to controls (-15.7 ± 3.9% vs. -21.1 ± 3.6% P &amp;lt; 0.001, -8.6 ± 2.9% vs. -12.6 ± 2.5% P &amp;lt; 0.001 and -7.1 ± 2.4% vs. -8.6 ± 2.2% P = 0.02, respectively) (Figure A, B, C). Patients with a high degree of LA fibrosis (dichotomized by the median value) had lower reservoir strain and conduit strain compared to patients with a low degree of LA fibrosis (-14.7 ± 4.0% vs. -16.8 ± 3.5%, P = 0.02 and -7.7 ± 2.7% vs. -9.5 ± 2.9%, P &amp;lt; 0.01, respectively). In contrast, no difference was found for LA contractile strain (-7.0 ± 2.3% vs. -7.3 ± 2.5%, P = 0.62) (Figure D, E, F). Conclusions This study shows impaired LA reservoir and conduit strain in AF patients with extensive atrial fibrosis. Of interest, LA contractile function was largely unaffected. Future studies are required to study the biologic nature of this association and possible therapeutic implications. Abstract Figure.

Left Atrial Strain and Function in Pediatric Hypertrophic Cardiomyopathy

Left atrial (LA) strain and dysfunction are early markers of diastolic dysfunction, associated with poor exercise capacity in adults with hypertrophic cardiomyopathy (HCM). Literature on assessment of LA mechanics in pediatric HCM is lacking. The aim of this study was to assess LA strain and LA function in pediatric patients who have HCM with (phenotype positive [P+]) and without (genotype positive, phenotype negative [G+P-]) ventricular hypertrophy and evaluate their correlation with exercise stress test parameters. Seventy-eight children (3-25years of age) with HCM (P+, n=46; G+P-, n=32) and 20 healthy control subjects were retrospectively studied. LA conduit function, reservoir function, and pump function were computed using phasic LA volumetric analysis. LA reservoir strain (LASr) and LA contractile strain were measured using speckle-tracking echocardiography. Exercise test findings within 12months of echocardiography were recorded. LA conduit function (36% vs 48%, P<.001) and LA reservoir function (137% vs 180%, P<.001) were lower in P+ than in G+P- patients. LA contractile function did not differ between the groups (31% vs 32%, P=.87). Compared with patients with G+P- HCM, those with P+HCM had lower four-chamber LASr (29% vs 41%, P<.001), two-chamber LASr (30% vs 41%, P<.001), average LASr (29% vs 42%, P<.001), and LA contractile strain (9% vs 12%, P=.016). In the cohort of patients with HCM who underwent stress testing (n=35), LA conduit function weakly correlated with aerobic capacity (r=0.42, P=.019). Children with P+HCM have reduced LA function, measurable by both volumetric and strain analysis. Altered LA mechanics are associated with poor exercise capacity. This study lays the foundation for the evaluation of novel LA parameters in pediatric HCM and warrants larger longitudinal studies to assess its clinical significance.

Correlations between Left Ventricular and Left Atrial Function Assessed by Speckle Tracking Echocardiography in Patients with Treated Well-Controlled Arterial Hypertension

Introduction. Even in patients with well-controlled arterial hypertension (AH) and without significant comorbidities, left ventricular (LV) and left atrial (LA) strain abnormalities may sometimes be found in speckle-tracking echocardiography. Therefore, the aim of this study was to investigate the correlation between LA strain and LV diastolic and systolic function in a group of patients with treated, well-controlled AH. Material and methods. LA contractile, conduit, and reservoir function, together with echocardiographic signs of LV diastolic function and LV global longitudinal strain (LV GLS), were assessed in 101 patients with treated, well-controlled AH who met the standard criteria of normal LV ejection fraction (LVEF) and normal LV diastolic function. Results. A relevant percentage of study participants presented lower than reference LV (−18.7% for LV GLS) and LA strain (32.9% for LAS during reservoir phase, LASr; −15.9% for LAS during contraction phase, LASct; and −13.9% for LAS during conduit phase, LAScd) values. Moreover, there were statistically significant differences in LA longitudinal strain (LAS) values (LASr (31.43 vs. 36.33; p = 0.0007) and LAS LAScd (−13.09 vs. −15.79; p = 0.008)) between patients with high (&gt;the absolute value of −20%) and lower (≤the absolute value of −20%) LV GLS, confirmed by significant correlations between LASr, LAScd, and GLS. In the correlations analysis between LAS values and LV diastolic function parameters, statistical significance was obtained for the following: LASct (contraction) versus e’avg, LASct versus E/A, LASct versus A, LAScd versus e’avg, LAScd versus E/A, and LAScd versus A. Conclusions. LV and LA strain abnormalities occurred within a significant percentage of patients with treated, well-controlled AH. Impaired LA strain is associated with lower LV strain and reduced LV diastolic function parameters, reflecting both the passive and active properties of the LA.

Persistent atrial fibrillation ablation in cardiac laminopathy: Electrophysiological findings and clinical outcomes

Little is known about persistent atrial fibrillation (AF) ablation in patients with cardiac laminopathy (CLMNA). We aimed to characterize atrial electrophysiological properties and to assess the long-term outcomes of persistent AF ablation in patients with CLMNA. All patients with CLMNA referred in our center for persistent AF ablation were retrospectively included. Left atrial (LA) volume, left atrial appendage (LAA) cycle length, interatrial conduction delay, and LA voltage amplitude were analyzed during the ablation procedure. Sinus rhythm maintenance and LA contractile function were assessed during long-term follow-up. From 2011 to 2020, 8 patients were included. The mean age was 47 ± 14 years, and 3 patients (38%) were women. The LA volume was 205.8 ± 43.7 mL; the LAA AF cycle length was 250.7 ± 85.6 ms; and the interatrial conduction delay was 296.5 ± 110.1 ms. Large low-voltage areas (>50% of the LA surface; <0.5 mV electrogram) were recorded in all 8 patients. Two patients had inadvertent LAA disconnection during ablation. All A waves recorded by pulsed Doppler in sinus rhythm were <30 cm/s before and after AF ablation. Early arrhythmia recurrence was recorded in 7 patients (87%) (time to recurrence 4 ± 4 months; 1.5 procedures per patient). After a mean follow-up of 4.4 ± 3.2 years, 4 patients underwent implantable cardioverter-defibrillator therapy for life-threatening ventricular arrhythmia and 3 patients finally underwent heart transplantation. Patients with persistent AF afflicted by CLMNA exhibit severe LA impairment because of large low-voltage areas, prolonged conduction velocity, and reduced contractile function. Ablation procedures have a limited effect with a high recurrence rate.

Quantification of left atrial contractile function using two-dimensional speckle tracking echocardiography in horses after conversion of atrial fibrillation to sinus rhythm

Introduction/ObjectivesIn horses, persistent atrial dysfunction is a prognostic indicator of recurrence of atrial fibrillation (AF). The objective of this study was to quantify left atrial (LA) contractile function in Warmblood horses after successful cardioversion of AF to sinus rhythm, using standard two-dimensional echocardiography (2DE) and two-dimensional speckle tracking (2DST) analyses, and to provide proof-of-concept for use of 2DST to detect LA contractile dysfunction in horses. Animals, materials, and methodsNineteen Warmblood horses with AF and successful transvenous electrical cardioversion (TVEC) or medical cardioversion using quinidine sulfate (QS) were included. Echocardiography was performed at 24 hr, 72 hr, and 1–6 months after cardioversion. Conventional 2DE-derived indices of LA size and function and global longitudinal strain (SL) and longitudinal strain rate (SRL) during LA contractile function were measured to detect differences in LA size and function over time and between treatment modalities. The association between 2DE-derived indices and global SL and SRL, respectively, and the agreement of the variables to detect LA dysfunction were assessed. ResultsGlobal SL and SRL, as well as active LA fractional area change (FAC) identified cases with LA dysfunction after TVEC and QS cardioversion and proved useful to demonstrate LA functional recovery over time. Agreement between active LA FAC and SL and SRL, respectively, to diagnose atrial dysfunction was substantial to fair at 24 hr after cardioversion and decreased with time. ConclusionThis study shows that 2DST is useful to quantify LA contractile dysfunction in horses after cardioversion of AF.

Cardiac remodelling and heart failure symptoms in patients with apical hypertrophic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Background Although earlier publications suggested a more benign clinical course for patients (pts) with apical hypertrophic cardiomyopathy (ApHCM), recent studies report increased morbidity and mortality, comparable to the prognosis of other HCM variants. Moreover, information regarding cardiac remodelling and its relationship with symptoms in pts with ApHCM is scarce. The aim of our study was to assess left ventricular (LV), right ventricular (RV) and left atrial (LA) remodelling in pts with ApHCM in comparison with non-apical variants of HCM (nonApHCM), and the impact of cardiac remodelling on heart failure symptoms. Methods One hundred fifty-one consecutive pts with HCM (52 ± 16 yrs, 47% men) in sinus rhythm and with preserved LV ejection fraction (16 pts with ApHCM and 135 pts with nonApHCM), were prospectively enrolled. Comprehensive echocardiography was performed in all, including the measurement of maximal LV wall thickness (LVWT), RV free wall thickness (RVWT) and maximal LA volume indexed to body surface area (LAVi). Global LV strain (ɛ), RVɛ, LAɛ and end-diastolic LA strain rate (ASr) were measured using speckle-tracking echocardiography (STE). The ratio of E to average e’ was used to estimate LV filling pressure. The degree of mitral regurgitation (1/2/3) has also been assessed. Heart failure symptoms were defined according to the New York Heart Association (NYHA) classification. Results Forty-eight pts in nonApHCM group had intraventricular obstruction. There were no significant differences between pts with and without ApHCM regarding: age (58 ± 20 vs 52 ± 16 yrs), gender distribution, RVWT, LVɛ (-14.9 ± 2.7 vs -13.9 ± 3.5 %), RVɛ (-19.6 ± 3.6 vs -10.0 ± 5.0%), LAɛ (19.2 ± 5.8 vs 16.4 ± 7.1%)(p &amp;gt; 0.05 for all). Pts with ApHCM had lower values for LVWT (17.2 ± 1.9 vs 21.4 ± 5.2 mm, p = 0.002), E/e’ (12.0 ± 5.8 vs 17.6 ± 8.5, p = 0.02) and LAVi (48 ± 16 vs 61 ± 25, p = 0.03) compared to pts with nonApHCM. Pts with ApHCM had slightly better LA contractile function as assessed by ASr (-1.23 ± 0.50 vs -0.97 ± 0.49 sec-1, p = 0.05). Mitral regurgitation was more often severe in nonApHCM pts (56/42/31 vs 10/4/0, p &amp;lt; 0.001). There was no significant difference between the percentage of symptomatic pts (NYHA class ≥2) in ApHCM vs nonApHCM group (p = 0.3). In the ApHCM group, symptomatic pts had significantly lower ASr compared to asymptomatic pts (-0.98 ± 0.35 vs -1.61 ± 0.46 sec-1, p = 0.01). Conclusions Despite of lower LVWT values, less severe MR and no obstruction, pts with apical HCM have similar prevalence of heart failure symptoms, and similar LV, RV and LA dysfunction compared to pts with non-apical HCM. Symptomatic pts with apical HCM have worse LA contractile function compared to asymptomatic pts.