Association of Left Atrial Structure and Function With Heart Failure in Older Adults

The Impact of Atrial Remodeling on the Efficacy of Catheter Ablation in Reducing Cardiovascular Risk in Atrial Fibrillation: Results from the CABANA Trial

BACKGROUND

The efficacy of catheter ablation in reducing major adverse events in atrial fibrillation (AF) is still inconclusive, warranting identification of clinical markers.

OBJECTIVE

To explore whether the benefit from catheter ablation varied across different extent of atrial remodeling in CABANA trial.

METHODS

The CABANA trial randomized 2204 participants with AF to catheter ablation or drug therapy. Patients underwent echocardiography measurement for left atrial diameter (LAD) at baseline constituted the current analysis population. The primary outcome was composite of death, disabling stroke, serious bleeding, or cardiac arrest.

RESULTS

Of 1130 patients with documented LAD at baseline (median LAD:44 mm), 570 were randomized to ablation and 560 to drug therapy. The estimated benefits of ablation versus drug therapy on primary outcome and total mortality were strongest in the lowest end of the LAD spectrum and declined substantially with LAD increasing. For primary outcome, the adjusted hazard ratios (aHRs) were 0.30 (95% CI, 0.11-0.78) in patients without LA enlargement (LAD≤40mm) and 0.92 (95% CI, 0.55-1.54) in those with LA enlargement (LAD>40mm) (Interaction P value= 0.035). The corresponding aHRs for total mortality were 0.09 (95% CI, 0.01-0.58) and 0.76 (95% CI, 0.40-1.41) in subgroups without and with LA enlargement (Interaction P value = 0.045).

CONCLUSION

Among CABANA patients without atrial enlargement, catheter ablation significantly reduced major cardiovascular events, while the prognostic benefit of ablation attenuated with atrial remodeling aggravation. Ablation at initial stage of atrial remodeling provided an effective early rhythm control strategy to reduce cardiovascular risk in AF.

Modest NT-proBNP Elevation in Septuagenarians Without Heart Failure Is Not Associated with Cardiac Alterations or Cardiovascular Outcomes

Background/Objectives: To assess the association between moderate N-terminal natriuretic peptide (NT-proBNP) and cardiac alterations and prognosis in septuagenarians without heart failure (HF). Methods: From the STROKESTOP II screening study, 230 individuals aged 75/76 years with NT-proBNP < 900 ng/L were randomly selected. Subjects with persistent atrial fibrillation (AF), more than mild valvular disease, or HF were excluded. Echocardiography was performed. NT-proBNP ≥ 125 ng/L and paroxysmal AF (pAF) on thumb ECG were used as grouping variables. Participants were followed up during a median of 5 years for cardiovascular mortality, HF, AF, and cerebrovascular events. Cox regression analysis was employed for prognostic assessment. Results: Three groups were identified: SR ≥ 125 (n = 94, no pAF and NT-proBNP ≥ 125 ng/L), pAF (n = 77, pAF and NT-proBNP ≥ 125 ng/L), and controls (n = 30, no pAF and NT-proBNP < 125 ng/L). NT-proBNP was not associated with structural (left atrial volume and left ventricular (LV) mass) or functional (E/e', LV strain) alterations in any group (p > 0.05). Cardiovascular risk factors (HR: 4.6; CI = 1.7-12.3; p = 0.002), but not NT-proBNP (HR: 1.9; CI = 0.7-5.1; p = 0.2), entailed a prognostic value for the composite endpoint of HF, AF, and cardiovascular death. Conclusions: In septuagenarians without HF, modest NT-proBNP elevation was not associated with echocardiographic changes or prognosis.

Markers of Left Atrial Myopathy: Prognostic Usefulness for Ischemic Stroke and Dementia in People in Sinus Rhythm

BACKGROUND

Various measures of abnormal left atrial (LA) structure or function (LA myopathy) are associated with a higher risk of ischemic stroke and dementia, independent of atrial fibrillation. However, limited data exist on their prognostic usefulness. Therefore, we aimed to assess the ability of markers of LA myopathy to improve the prediction of ischemic stroke and dementia.

METHODS

The ARIC study (Atherosclerosis Risk in Communities) is a prospective community-based cohort study. For this analysis, we included participants who attended visit 5 (2011-2013) without a history of stroke or atrial fibrillation and had a 12-lead ECG and a transthoracic echocardiogram. Markers of LA myopathy included P wave abnormalities from 12-lead ECG, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and LA volume and strain parameters from the echocardiogram. The primary composite outcome comprised ischemic stroke and dementia, which were ascertained through hospital surveillance, cohort follow-up, and death registries. To determine improvement in risk prediction of the composite outcome, each marker was individually added to a model that included CHA2DS2-VASc variables, and Akaike information criterion, C statistic, and its change were computed. Cox proportional hazards models were used to assess the independent association of LA myopathy markers with the outcome.

RESULTS

Among 4712 participants (59% female; mean age, 74 years), 193 ischemic strokes and 769 dementia cases were ascertained over a median follow-up of 8.3 years. Of LA myopathy markers, only LA reservoir strain and NT-proBNP significantly improved C statistic when added to the CHA2DS2-VASc model (base C statistic, 0.677) for the prediction of the composite outcome. Adding the LA reservoir yielded the highest increase in C statistic (0.010 [95% CI, 0.003-0.017]), and the model including the LA reservoir showed the lowest Akaike information criterion. In multivariable regression models, LA volume index, NT-proBNP, and LA strain parameters were significantly associated with the composite outcome.

CONCLUSIONS

Of various LA myopathy markers, LA reservoir yields the greatest improvement in the prediction of ischemic stroke and dementia, supporting its use to identify people at high risk of cerebrovascular events and dementia.

Gut microbiota and atrial cardiomyopathy

Atrial cardiomyopathy is a multifaceted heart disease characterized by structural and functional abnormalities of the atria and is closely associated with atrial fibrillation and its complications. Its etiology involves a number of factors, including genetic, infectious, immunologic, and metabolic factors. Recent research has highlighted the critical role of the gut microbiota in the pathogenesis of atrial cardiomyopathy, and this is consistent with the gut-heart axis having major implications for cardiac health. The aim of this work is to bridge the knowledge gap regarding the interactions between the gut microbiota and atrial cardiomyopathy, with a particular focus on elucidating the mechanisms by which gut dysbiosis may induce atrial remodeling and dysfunction. This article provides an overview of the role of the gut microbiota in the pathogenesis of atrial cardiomyopathy, including changes in the composition of the gut microbiota and the effects of its metabolites. We also discuss how diet and exercise affect atrial cardiomyopathy by influencing the gut microbiota, as well as possible future therapeutic approaches targeting the gut-heart axis. A healthy gut microbiota can prevent disease, but ecological dysbiosis can lead to a variety of symptoms, including the induction of heart disease. We focus on the pathophysiological aspects of atrial cardiomyopathy, the impact of gut microbiota dysbiosis on atrial structure and function, and therapeutic strategies exploring modulation of the microbiota for the treatment of atrial cardiomyopathy. Finally, we discuss the role of gut microbiota in the treatment of atrial cardiomyopathy, including fecal microbiota transplantation and oral probiotics or prebiotics. Our study highlights the importance of gut microbiota homeostasis for cardiovascular health and suggests that targeted interventions on the gut microbiota may pave the way for innovative preventive and therapeutic strategies targeting atrial cardiomyopathy.

Left Atrial Markers in Diagnosing and Prognosticating Non-Ischemic Cardiomyopathies: Ready for Prime Time?

The left atrium (LA) is pivotal in cardiac hemodynamics, serving as a dynamic indicator of left ventricular (LV) compliance and diastolic function. The LA undergoes structural and functional adaptations in response to hemodynamic stress, infiltrative processes, myocardial injury, and arrhythmic triggers. Remodeling of the LA in response to these stressors directly impacts pulmonary circulation, eventually leading to pulmonary capillary involvement, pulmonary artery hypertension, and eventually right ventricular failure. LA dysfunction and fibrosis also contribute to the future risk of atrial arrhythmias and mitral regurgitation. The parameters of LA size and function are being recognized as robust markers for the progression of several cardiac pathologies as well as important tools for prognostication. In this article, we briefly describe the different modalities and markers used to evaluate LA pathology in patients with nonischemic cardiomyopathies (NICM). We then provide an overview of the studies that compared the association of the different LA parameters with disease severity and future prognosis. We also identify the gaps in knowledge before these LA parameters make a case for clinical adoption.

Left atrial reservoir strain as a predictor of cardiac dysfunction in a murine model of pressure overload

AIM

Left atrial (LA) strain is emerging as a valuable metric for evaluating cardiac function, particularly under pathological conditions such as pressure overload. This preclinical study investigates the predictive utility of LA strain on cardiac function in a murine model subjected to pressure overload, mimicking pathologies such as hypertension and aortic stenosis.

METHODS

High-resolution ultrasound was performed in a cohort of mice (n = 16) to evaluate left atrial and left ventricular function at baseline and 2 and 4 weeks after transverse aortic constriction (TAC). Acute adaptations in cardiac function were assessed in a subgroup of mice (n = 10) with 3 days post-TAC imaging.

RESULTS

We report an increase in LA max volume from 11.0 ± 4.3 μL at baseline to 26.7 ± 16.7 μL at 4 weeks (p = 0.002) and a decrease in LA reservoir strain from 20.8 ± 5.4% at baseline to 10.2 ± 6.9% at 4 weeks (p = 0.001). In the acute phase, LA strain dysfunction was present at 3 days (p < 0.001), prior to alterations in LA volume (p = 0.856) or left ventricular (LV) ejection fraction (p = 0.120). LA reservoir strain correlated with key indicators of cardiac performance including left ventricular (LV) ejection fraction (r = 0.541, p < 0.001), longitudinal strain (r = -0.637, p < 0.001), and strain rate (r = 0.378, p = 0.007). Furthermore, markers of atrial structure and function including LA max volume (AUC = 0.813, p = 0.003), ejection fraction (AUC = 0.853, p = 0.001), and strain (AUC = 0.884, p < 0.001) all predicted LV dysfunction.

CONCLUSION

LA strain and function assessments provide a reliable, non-invasive method for the early detection and prediction of cardiac dysfunction in a model of pressure overload.

Left Atrial Function and Incident Heart Failure in Older Adults

BACKGROUND

Heart failure (HF) prevalence is increasing, especially among older adults. Left atrial (LA) dysfunction is often associated with HF, but it is unclear whether it may contribute to its development. We investigated whether measures of LA function can predict the development of HF in older adults without a history of cardiovascular events.

METHODS AND RESULTS

Seven hundred ninety-five participants from a triethnic (white, Black, Hispanic) community-based cohort of adults age ≥55 without a history of cardiovascular events underwent standard, three-dimensional, and speckle-tracking echocardiography. Left atrial volumes, LA strain, LA stiffness, and LA coupling index (LACI) were measured. Longitudinal follow-up was conducted, and new-onset HF was ascertained through standardized interviews, in-person visits, and active hospital surveillance of admission and discharge ICD-9 codes. Risk analysis with a cause-specific hazards regression model was used to assess the association of LA variables with incident HF, adjusting for other HF risk factors. The mean age was 70.9 ± 9.2 years (297 men, 498 women). During a mean follow-up of 11.4 years, new-onset HF occurred in 345 participants (43.4%). All measures of LA morphology and function were associated with incident HF (all P < .05). In multivariable analysis, LA stiffness and LACI (adjusted hazard ratio = 2.06; 95% CI, 1.08-3.94; adjusted hazard ratio = 1.25; 95% CI, 1.09-1.43, respectively) remained associated with incident HF. After further adjustment for left ventricular global longitudinal strain, only LACI remained associated with incident HF (adjusted hazard ratio = 1.22; 95% CI, 1.05-1.42).

CONCLUSIONS

Left atrial coupling index is a stronger independent predictor for incident HF in older adults than LA volumes and strain and may improve HF risk stratification.

Heart failure with preserved ejection fraction and atrial fibrillation: epidemiology, pathophysiology, and diagnosis interplay

Heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) are increasingly prevalent cardiovascular conditions, particularly among the elderly population. These two conditions share common risk factors and often coexist, leading to a complex interplay that alters the clinical course of each other. The pathophysiology of HFpEF is multifaceted and intricately linked, with atrial disease serving as a common pathophysiological pathway. Diagnosis of HFpEF in the setting of AF, and vice versa, can be challenging; thus, effective screening and diagnostic strategies are needed. Understanding the complex relationship between HFpEF and AF is crucial for optimal patient management by timely disease recognition and identification of therapeutic interventions or treatment strategies.

Diagnostic and prognostic potential of left atrial strain in cardiovascular disease: a narrative review

Left atrial strain (LAS) was recently introduced as a parameter that reflects on left atrial function. Consequently, changes in LAS can inform the development of cardiovascular diseases, hence providing a window for non-invasive and cost-effective testing of these diseases and their complications at early stages of development, potentially offering a segway towards preventive interventions. LAS has yet to be implemented into standard practice. Therefore, we aimed to synthesize the current evidence on the diagnostic and prognostic potentials of LAS in a variety of cardiovascular diseases. We attempted to elucidate sufficient evidence to support uptake into clinical practice. A systematic search of four databases (Medline, PubMed, Embase, CINAHL) was performed for articles published within the last 5 years, for inclusion in this narrative review. A total of 3921 articles were identified, among which only 43 articles were included. LAS showed diagnostic potential in detecting (1) paroxysmal atrial fibrillation in stroke patients, (2) left atrial appendage dysfunction in patients with nonvalvular atrial fibrillation and heart failure with reduced ejection fraction, and finally (3) diastolic dysfunction in patients with arrhythmias, valvulopathies, acute coronary syndrome, primary arterial hypertension, and heart failure. LAS was also prognostic for the development of (1) atrial fibrillation in hypertensive patients, cardiovascular events in patients with (2) valvular diseases and (3) ischemic heart diseases, and (4) heart failure in patients with and without diastolic dysfunction. This review highlights the potential of LAS in identifying certain cardiac pathologies and their repercussions on patient prognosis, which should prompt courageous integration into the clinical workup while emphasizing areas for future research to guarantee successful and safe implementation into clinical practice.

Association of left atrial function with frailty: The Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND

Frailty is common in people with cardiovascular disease. Worse left atrial (LA) function is an independent risk factor for cardiovascular disease. However, whether worse LA function is associated with frailty is unclear.

METHODS

We included 3292 older adults from the Atherosclerosis Risk in Communities study who were non-frail at baseline (visit 5, 2011-2013) and had LA function (reservoir, conduit, and contractile strain) measured from two-dimensional speckle-tracking echocardiography. LA stiffness index was calculated as a ratio of E/e' to LA reservoir strain. Frailty was defined using the validated Fried frailty phenotype. Incident frailty was assessed between 2016 and 2019 during two follow-up visits. LA function was analyzed as quintiles. Multivariable logistic regression examined odds of incident frailty.

RESULTS

Median (interquartile range [IQR]) age was 74 (71-77) years, 58% were female, and 214 (7%) participants developed frailty during a median (IQR) follow-up of 6.3 (5.6-6.8) years. After adjusting for baseline confounders and incident cardiovascular events during follow-up, the odds of developing frailty was 2.42 (1.26-4.66) times greater among participants in the lowest (vs highest) quintile of LA reservoir strain and 2.41 (1.11-5.22) times greater among those in the highest (vs lowest) quintile of LA stiffness index. Worse LA function was significantly associated with the development of exhaustion, but not the other components of the Fried frailty phenotype.

CONCLUSIONS

Worse LA function is associated with higher incidence of frailty and exhaustion component independent of LA size and left ventricular function. Future studies are needed to elucidate the underlying mechanisms that drive the observed association.

Cardiac mechanics and the risk of atrial fibrillation in a community-based cohort of older adults

AIMS

Assessment of cardiac structure and function improves risk prediction of new-onset atrial fibrillation (AF) in different populations. We aimed to comprehensively compare standard and newer measures of cardiac structure and function in improving prediction of AF in a cohort of older adults without history of AF and stroke.

METHODS AND RESULTS

We included 5050 participants without prevalent AF and stroke (mean age 75 ± 5 years, 59% women, and 22% Black) from the Atherosclerosis Risk in Communities (ARIC) study who underwent complete two-dimensional echocardiography, including speckle-tracking analysis of the left ventricle (LV) and left atrium (LA). We assessed the association of cardiac measures with incident AF (including atrial flutter) and quantified the extent to which these measures improved model discrimination and risk classification of AF compared with the CHARGE-AF score. Over a median follow-up time of 7 years, 676 participants developed AF (incidence rate 2.13 per 100 person-years). LV mass index and wall thickness, E/e', and measures of LA structure and function, but not LV systolic function, were associated with incident AF, after accounting for confounders. Above all, LA reservoir strain, contraction strain, and LA minimal volume index (C-statistics [95% confidence interval]: 0.73 [0.70, 0.75], 0.72 [0.70, 0.75], and 0.72 [0.69, 0.75], respectively) significantly improved the risk discrimination of the CHARGE-AF score (baseline C-statistic: 0.68 [0.65, 0.70]) and achieved the highest category-based net reclassification improvement (29%, 24%, and 20%, respectively).

CONCLUSION

In a large cohort of older adults without prevalent AF and stroke, measures of LA function improved the prediction of AF more than other conventional cardiac measures.

Echocardiographic Assessment of Left Atrial Mechanics in Patients with Atrial Fibrillation Undergoing Electrical Cardioversion: A Systematic Review

Background: To date, only a few studies have evaluated left atrial (LA) mechanics in patients with atrial fibrillation (AF) scheduled for electrical cardioversion (ECV). The present systematic review has been primarily designed to summarize the main findings of these studies and to examine the overall effect of AF on left atrial reservoir strain (LASr) in patients undergoing ECV. Methods: All the echocardiographic studies evaluating the effect of AF on LA mechanics in patients scheduled for ECV, selected from the PubMed and EMBASE databases, were included. There was no limitation of time period. The risk of bias was assessed by using the National Institutes of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Results: The full texts of 12 studies with 880 AF patients were analyzed. The pooled ECV success rate was 91.5% (range 65.8-100%). Over a median follow-up of 5.4 months (range 0.3-12 months), 35.2% of the patients (range 5-68.8%) experienced AF recurrence. At baseline, the average LASr was 11.4% (range 6.2-17.7%). A reduced LASr before ECV was strongly correlated with reduced left atrial appendage (LAA) flow velocities and/or thrombosis. The main independent predictors of cardioversion failure were impaired LASr and previous AF history. A severe LASr deterioration was independently correlated with AF recurrence after ECV. The other independent predictors of AR relapses were LA asynchrony, reduced difference between post- and pre-ECV LASr, and reduced right atrial reservoir strain. Conclusions: LASr assessment before ECV may provide useful prognostic information about AF relapses and improve the refinement of the thromboembolic risk of AF patients scheduled for ECV.

Effect of Semaglutide on Cardiac Structure and Function in Patients With Obesity-Related Heart Failure

BACKGROUND

Obesity is associated with adverse cardiac remodeling and is a key driver for the development and progression of heart failure (HF). Once-weekly semaglutide (2.4 mg) has been shown to improve HF-related symptoms and physical limitations, body weight, and exercise function in patients with obesity-related heart failure with preserved ejection fraction (HFpEF), but the effects of semaglutide on cardiac structure and function in this population remain unknown.

OBJECTIVES

In this echocardiography substudy of the STEP-HFpEF Program, we evaluated treatment effects of once-weekly semaglutide (2.4 mg) vs placebo on cardiac structure and function.

METHODS

Echocardiography at randomization and 52 weeks was performed in 491 of 1,145 participants (43%) in the STEP-HFpEF Program (pooled STEP-HFpEF [Semaglutide Treatment Effect in People with Obesity and HFpEF] and STEP-HFpEF DM [Semaglutide Treatment Effect in People with Obesity, HFpEF, and Type 2 Diabetes] trials). The prespecified primary outcome was change in left atrial (LA) volume, with changes in other echocardiography parameters evaluated as secondary outcomes. Treatment effects of semaglutide vs placebo were assessed using analysis of covariance stratified by trial and body mass index, with adjustment for baseline parameter values.

RESULTS

Overall, baseline clinical and echocardiographic characteristics were balanced among those receiving semaglutide (n = 253) and placebo (n = 238). Between baseline and 52 weeks, semaglutide attenuated progression of LA remodeling (estimated mean difference [EMD] in LA volume, -6.13 mL; 95% CI: -9.85 to -2.41 mL; P = 0.0013) and right ventricular (RV) enlargement (EMD in RV end-diastolic area: -1.99 cm2; 95% CI: -3.60 to -0.38 cm2; P = 0.016; EMD in RV end-systolic area: -1.41 cm2; 95% CI: -2.42 to -0.40] cm2; P = 0.0064) compared with placebo. Semaglutide additionally improved E-wave velocity (EMD: -5.63 cm/s; 95% CI: -9.42 to -1.84 cm/s; P = 0.0037), E/A (early/late mitral inflow velocity) ratio (EMD: -0.14; 95% CI: -0.24 to -0.04; P = 0.0075), and E/e' (early mitral inflow velocity/early diastolic mitral annular velocity) average (EMD: -0.79; 95% CI: -1.60 to 0.01; P = 0.05). These associations were not modified by diabetes or atrial fibrillation status. Semaglutide did not significantly affect left ventricular dimensions, mass, or systolic function. Greater weight loss with semaglutide was associated with greater reduction in LA volume (Pinteraction = 0.033) but not with changes in E-wave velocity, E/e' average, or RV end-diastolic area.

CONCLUSIONS

In the STEP-HFpEF Program echocardiography substudy, semaglutide appeared to improve adverse cardiac remodeling compared with placebo, further suggesting that treatment with semaglutide may be disease modifying among patients with obesity-related HFpEF. (Research Study to Investigate How Well Semaglutide Works in People Living With Heart Failure and Obesity [STEP-HFpEF]; NCT04788511; Research Study to Look at How Well Semaglutide Works in People Living With Heart Failure, Obesity and Type 2 Diabetes [STEP-HFpEF DM]; NCT04916470).

Atrial Mechanics, Atrial Cardiomyopathy and Impact of Atrial Interventions

Our comprehension of atrial mechanics, atrial cardiomyopathy and their clinical implications across various cardiovascular conditions has advanced significantly. Atrial interventions can have differing effects on atrial mechanics. With the rapid increase in the use of atrial interventions, it is crucial for investigators and clinicians to acknowledge the potential adverse effects of these interventions on atrial mechanics that might not be clinically significant at the time of interventions. Recognizing the preclinical stage of atrial maladaptation might enable early interventions before the development of irreversible atrial remodeling and clinical manifestation. We review normal atrial function and mechanics, and atrial cardiomyopathy in select cardiovascular conditions. We also summarize and discuss the current evidence of the impact of various atrial interventions on atrial function and mechanics.

Association of central arterial stiffness with atrial myopathy: the Atherosclerosis Risk in Communities (ARIC) study

Atrial myopathy-defined as abnormal left atrial (LA) size and function-is associated with an increased risk of atrial fibrillation, heart failure, and dementia. Central arterial stiffness is associated with increased atrial afterload and fibrosis and may be a risk factor for atrial myopathy. We examined the association of carotid-femoral pulse wave velocity (cfPWV) with LA function and assessed potential causal relationships. We included 2825 Atherosclerosis Risk in Communities (ARIC) study participants from Visit 5 (2011-2013). cfPWV was related to echocardiographic LA function continuously per 1-SD and categorically in quartiles. Mendelian randomization (MR) analysis was performed using U.K. Biobank-derived genetic variants associated with arterial stiffness index and cardiac magnetic resonance measures of LA function. When analyzed per SD increment (297.6 cm/s), higher cfPWV was significantly associated with lower LA reservoir and conduit strain (β = -0.53%, 95% CI [-0.81, -0.25] and β = -0.46%, 95% CI [-0.68, -0.25], respectively) after adjusting for demographics, clinical characteristics, systolic blood pressure, and left ventricular (LV) morphology and function. In MR analyses there was a non-significant inverse association of arterial stiffness index with LA total, passive, and active emptying fractions. Higher cfPWV is associated with lower LA reservoir and conduit strain, independent of systolic blood pressure and LV morphology and function. No evidence for a causal relationship between arterial stiffness index and alterations in LA function was found. Future studies should examine the prospective association of central arterial stiffness with LA function alterations.

Prognostic value of left atrial size and function by cardiac magnetic resonance in non-ischemic cardiomyopathy

To evaluate left atrial (LA) function and strain parameters by cardiac magnetic resonance imaging (CMR) in patients with non-ischemic cardiomyopathy (NICM) and evaluate the association of these parameters with long-term clinical outcomes. We retrospectively included 92 patients with NICM and 50 subjects with no significant cardiovascular disease (control group). We calculated LA volumes using the Simpson area-length method to derive LA ejection fraction and expansion index. LA reservoir (ƐR), conduit (ƐCD), and contractile strain (ƐCT) were measured using dedicated CMR software (cvi42, Circle Cardiovascular Imaging Inc., version 5.14). An adjusted multivariate regression analysis was performed to determine the association of LA parameters with death and heart failure hospitalization (HFH). NICM patients were older with male preponderance. The mean age for NICM patients was 59.6 ± 15.9 years, 64% males, and 73% whites versus 52.2 ± 12.4 years, 34% male and 64% white for controls. LA strain patterns were significantly lower in NICM patients when compared to controls. During a median follow-up of 58.9 months, 12 patients (13%) died and 33(35.9%) had a HFH. None of the clinical or CMR factors were significantly associated with death. On multivariate analysis, after adjusting for age and significant univariate variables, ƐR was the only variable significantly associated with the HFH (OR 0.98, CI 0.96-1.0). Unadjusted and adjusted Cox proportional hazard models divided by the median ƐR (~ 18%) showed a significant difference in HFH over time (χ2 statistic = 21.1; P value = 0.03). In NICM patients, all LA strain components were reduced. ƐR was found to be significantly associated with HFH.

Biomarkers of atrial fibrillation-related pathways and left atrial structure and function in an overweight and obese population

Background

Exploring longitudinal associations of blood biomarkers with left atrial (LA) structure and function can enhance our understanding of atrial fibrillation (AF) etiopathogenesis.

Methods

We studied 532 participants of the PREDIMED-Plus trial, a multicenter randomized trial in overweight and obese adults with metabolic syndrome. At baseline, 3 and 5 years after randomization, participants underwent transthoracic echocardiography and provided blood for serum biomarker measurements [propeptide of procollagen type I (PICP), high-sensitivity (hs) troponin T (hsTnT), hs C-reactive protein (hsCRP), 3-nitrotyrosine (3-NT), and N-terminal propeptide of B-type natriuretic peptide (NT-proBNP)]. Outcomes of interest included LA peak systolic longitudinal strain (LA PSLS), LA volume index (LAVi), LA function index (LAFi), and LA stiffness index (LASi). We performed cross-sectional and longitudinal analyses to evaluate relationships between log-transformed biomarkers and echocardiographic measurements using multiple linear regression and mixed models.

Results

The participants in this analysis had a mean age of 65.0 (SD 4.8) years, and 40% were females. At baseline, increased NT-proBNP and hsTnT were associated with larger LAVi and worse LA function as measured by the LAFi, LASi, and LA PSLS. Longitudinally, higher NT-proBNP, but not higher hsTnT, was associated with increased LAVi and worsening LA function. Over 5 years, 1 unit increase in log(NT-proBNP) was associated with steeper decline in LA PSLS (-0.19%, 95% CI -0.35%, -0.02%) and greater increase in LAVi (0.28 mL/m2, 95% CI 0.10, 0.45) each year. PICP, hsCRP, and 3-NT did not show consistently significant associations with LA outcomes at baseline and through 5 years.

Conclusion

In an overweight and obese population, higher NT-proBNP was associated with LA volume enlargement and worsening LA function over 5 years. The implications of these findings for the prevention and prediction of AF warrant further investigation.

Association of Cumulative Systolic Blood Pressure With Left Atrial Function in the Setting of Normal Left Atrial Size: The Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Lower left atrial (LA) function is associated with increased risk for cardiovascular disease events; data on risk factors for impaired LA function are limited. We evaluated the effect of cumulative systolic blood pressure (cSBP) from midlife to older age on LA strain in adults with normal LA size.

METHODS

We included participants in the Atherosclerosis Risk in Communities study with LA strain measured on the visit 5 echocardiogram (2011-13), excluding those with atrial fibrillation and LA volume index >34 mL/m2. The cSBP was calculated from visit 1 (1987-89) through visit 5. Linear regression models were used to evaluate associations between cSBP and LA strain measures.

RESULTS

A total of 3,859 participants with a mean (SD) age of 75.2 (5.0) years were included in the analysis; 725 (18.8%) were Black and 2,342 (60.7%) were women. After adjusting for demographics, cardiovascular disease risk factors, heart failure, and coronary heart disease, each 10 mm Hg increase in cSBP was associated with 0.32% (95% CI, -0.52%, -0.13%) and 0.37% (95% CI, -0.51%, -0.22%) absolute reduction in LA reservoir and conduit strain, respectively. Associations were attenuated after adjustment for left ventricular (LV) systolic and diastolic function and mass (-0.12%: 95% CI, -0.31, 0.06 for reservoir strain; and -0.24%: 95% CI -0.38%, -0.10% for conduit strain). In subgroup analyses, the association of cSBP with conduit strain was statistically significant among those with normal LV systolic and diastolic function.

CONCLUSIONS

Cumulative exposure to elevated blood pressure from midlife to late life was modestly associated with lower LA reservoir and conduit strain in older adults with normal LA size, mostly related to the effect of blood pressure on LV function and mass. However, the association of cSBP and LA conduit strain in subgroups with normal LV function suggests that LA remodeling in response to hypertension occurs before LV dysfunction is detected on echocardiography.

Current and Clinically Relevant Echocardiographic Parameters to Analyze Left Atrial Function

The evaluation of the left atrial (LA) size using the LA volume index (LAVI) is clinically relevant due to its prognostic significance in various conditions. Nonetheless, adding a LA function assessment to the LAVI provides further clinical and prognostic information in different cardiovascular (CV) diseases. The assessment of LA function by echocardiography primarily includes volumetric measurements (LA ejection fraction [LAEF]), tissue Doppler imaging (TDI) (mitral annular late diastolic velocity [a']), and speckle-tracking methods, such as LA longitudinal reservoir strain (LA strain). This review analyzes and discusses the current medical evidence and potential clinical usefulness of these different methods to analyze LA function.

Association of Left Atrial Function With Incident Chronic Kidney Disease in Older Adults

Objective

To examine the association of left atrial (LA) function with incident chronic kidney disease (CKD) and assess the clinical utility of adding LA function to a CKD risk prediction equation.

Patients and Methods

We included 4002 Atherosclerosis Risk in Communities study participants without prevalent CKD (mean ± SD age, 75±5 years; 58% female, 18% Black). Left atrial function (reservoir, conduit, and contractile strain) was evaluated by 2D-echocardiograms on 2011 to 2013. Chronic kidney disease was defined as greater than 25% decline in estimated glomerular filtration rate of less than 60 mL/min/1.73 m2, end-stage kidney disease, or hospital records. Cox proportional hazards models were used. Risk prediction and decision curve analyses evaluated 5-year CKD risk by diabetes status.

Results

Median follow-up was 7.2 years, and 598 participants developed incident CKD. Incidence rate for CKD was 2.29 per 100 person-years. After multivariable adjustments, the lowest quintile of LA reservoir, conduit, and contractile strain (vs highest quintile) had a higher risk of CKD (hazard ratios [95% CIs]: 1.94 [1.42-2.64], 1.62 [1.19-2.20], and 1.49 [1.12-1.99]). Adding LA reservoir strain to the CKD risk prediction equation variables increased the C-index by 0.026 (95% CI: 0.005-0.051) and 0.031 (95% CI: 0.006-0.058) in participants without and with diabetes, respectively. Decision curve analysis found the model with LA reservoir strain had a higher net benefit than the model with CKD risk prediction equation variables alone.

Conclusion

Lower LA function is independently associated with incident CKD. Adding LA function to the CKD risk prediction enhances prediction and yields a higher clinical net benefit. These findings suggest that impaired LA function may be a novel risk factor for CKD.

Proteomic profiles of left atrial volume and its influence on response to spironolactone: Findings from the HOMAGE trial and STANISLAS cohort

AIMS

High left ventricular filling pressure increases left atrial volume and causes myocardial fibrosis, which may decrease with spironolactone. We studied clinical and proteomic characteristics associated with left atrial volume indexed by body surface area (LAVi), and whether LAVi influences the response to spironolactone on biomarker expression and clinical variables.

METHODS AND RESULTS

In the HOMAGE trial, where people at risk of heart failure were randomized to spironolactone or control, we analysed 421 participants with available LAVi and 276 proteomic measurements (Olink) at baseline, month 1 and 9 (mean age 73 ± 6 years; women 26%; LAVi 32 ± 9 ml/m2). Circulating proteins associated with LAVi were also assessed in asymptomatic individuals from a population-based cohort (STANISLAS; n = 1640; mean age 49 ± 14 years; women 51%; LAVi 23 ± 7 ml/m2). In both studies, greater LAVi was significantly associated with greater left ventricular masses and volumes. In HOMAGE, after adjustment and correction for multiple testing, greater LAVi was associated with higher concentrations of matrix metallopeptidase-2 (MMP-2), insulin-like growth factor binding protein-2 (IGFBP-2) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) (false discovery rates [FDR] <0.05). These associations were externally replicated in STANISLAS (all FDR <0.05). Among these biomarkers, spironolactone decreased concentrations of MMP-2 and NT-proBNP, regardless of baseline LAVi (pinteraction > 0.10). Spironolactone also significantly reduced LAVi, improved left ventricular ejection fraction, lowered E/e', blood pressure and serum procollagen type I C-terminal propeptide (PICP) concentration, a collagen synthesis marker, regardless of baseline LAVi (pinteraction > 0.10).

CONCLUSION

In individuals without heart failure, LAVi was associated with MMP-2, IGFBP-2 and NT-proBNP. Spironolactone reduced these biomarker concentrations as well as LAVi and PICP, irrespective of left atrial size.

The Clinical Applications of Left Atrial Strain: A Comprehensive Review

Left atrial (LA) strain imaging, which measures the deformation of the LA using speckle-tracing echocardiography (STE), has emerged recently as an exciting tool to help provide diagnostic and prognostic information for patients with a broad range of cardiovascular (CV) pathologies. Perhaps due to the LA's relatively thin-walled architecture compared with the more muscular structure of the left ventricle (LV), functional changes in the left atrium often precede changes in the LV, making LA strain (LAS) an earlier marker for underlying pathology than many conventional echocardiographic parameters. LAS imaging is typically divided into three phases according to the stage of the cardiac cycle: reservoir strain, which is characterized by LA filling during systole; conduit strain, which describes LA deformation during passive LV filling; and booster strain, which provides information on the LA atrium during LA systole in late ventricular diastole. While additional large-population studies are still needed to further solidify the role of LAS in routine clinical practice, this review will discuss the current evidence of its use in different pathologies and explore the possibilities of its applications in the future.

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

BACKGROUND AND AIMS

Although 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 RESULTS

This 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.

CONCLUSIONS

A 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 ventricular and atrial myocardial strain in heart failure with preserved ejection fraction: the evidence so far and prospects for phenotyping strategy

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) represents a significant proportion of heart failure cases. Accurate diagnosis is challenging due to the heterogeneous nature of the disease and limitations in traditional echocardiographic parameters.

MAIN BODY

This review appraises the application of Global Longitudinal Strain (GLS) and Left Atrial Strain (LAS) as echocardiographic biomarkers in the diagnosis and phenotyping of HFpEF. Strain imaging, particularly Speckle Tracking Echocardiography, offers a superior assessment of myocardial deformation, providing a more detailed insight into left heart function than traditional metrics. Normal ranges for GLS and LAS are considered, acknowledging the impact of demographic and technical factors on these values. Clinical studies have demonstrated the prognostic value of GLS and LAS in HFpEF, especially in predicting cardiovascular outcomes and distinguishing HFpEF from other causes of dyspnea. Nevertheless, the variability of strain measurements and the potential for false-negative results underline the need for careful clinical interpretation. The HFA-PEFF scoring system's integration of these biomarkers, although systematic, reveals gaps in addressing the full spectrum of HFpEF pathology. The combined use of GLS and LAS has been suggested to define HFpEF phenogroups, which could lead to more personalized treatment plans.

CONCLUSION

GLS and LAS have emerged as pivotal tools in the non-invasive diagnosis and stratification of HFpEF, offering a promise for tailored therapeutic strategies. Despite their potential, a structured approach to incorporating these biomarkers into standard diagnostic workflows is essential. Future clinical guidelines should include clear directives for the combined utilization of GLS and LAS, accentuating their role in the multidimensional assessment of HFpEF.

Left ventricular to left arial volume ratio in the assessment of filling pressure in patients with dyspnoea and preserved ejection fraction

Introduction

Assessing filling pressure (FP) remains a clinical challenge despite advancements in non-invasive imaging techniques. This study investigates the utility of echocardiographic left ventricular (LV) to left atrial (LA) volume ratio in estimating the resting FP in patients with dyspnoea and preserved ejection fraction (EF).

Methods

This study is a prospective, single-centre analysis of 53 consecutive patients with dyspnoea (New York Heart Association grade 2 or 3) and LVEF of ≥50% (mean age 71 ± 10 years) who underwent cardiac catheterisation, including direct measurement of LA pressure at rest using retrograde technique. Echocardiographic data were obtained 1.5 ± 1.0 h after cardiac catheterisation. The patients were divided into two groups: Group 1 consisted of individuals with elevated FP, indicated by a mean LA pressure or mean pulmonary capillary wedge pressure of >12 mmHg, and Group 2 comprised of patients with normal FP. The LV and LA volumes were measured at three specific points: the minimum volume (LVES, LAmin), the volume during diastasis (LVdias, LAdias), and the maximum volume (LVED, LAmax). The corresponding LV/LA volume ratios were analysed: end-systole (LVES/LAmax), diastasis (LVdias/LAdias), and end-diastole (LVED/LAmin).

Results

The patients in Group 1 exhibited lower LV/LA volume ratios compared with those in Group 2 (LVES/LAmax 0.44 ± 0.12 vs. 0.60 ± 0.23, P = 0.0032; LVdias/LAdias 1.13 ± 0.30 vs. 1.56 ± 0.49, P = 0.0007; LVED/LAmin 2.71 ± 1.57 vs. 4.44 ± 1.70, P = 0.0004). The LV/LA volume ratios correlated inversely with an increased FP (LVES/LAmax, r = -0.40, P = 0.0033; LVdias/LAdias, r = -0.45, P = 0.0007; LVED/LAmin, r = -0.55, P < 0.0001). Among all the measurements, the LVdias/LAdias ratio demonstrated the highest discriminatory power to distinguish patients with elevated FP from normal FP, with a cut-off value of ≤1.24 [area under the curve (AUC) = 0.822] for the entire group, encompassing both sinus rhythm and atrial fibrillation. For patients in sinus rhythm specifically, the cut-off value was ≤1.28 (AUC = 0.799), with P < 0.0001 for both. The LVdias/LAdias index demonstrated non-inferiority to the E/e' ratio [ΔAUC = 0.159, confidence interval (CI) = -0.020-0.338; P = 0.0809], while surpassing the indices of LA reservoir function (ΔAUC = 0.249, CI = 0.044-0.454; P = 0.0176), LA reservoir strain (ΔAUC = 0.333, CI = 0.149-0.517; P = 0.0004), and LAmax index (ΔAUC = 0.224, CI = 0.043-0.406; P = 0.0152) in diagnosing patients with elevated FP.

Conclusion

The study presents a straightforward and reproducible method for non-invasive estimation of FP using routine TTE in patients with dyspnoea and preserved EF. The LVdias/LAdias index emerges as a promising indicator for identifying elevated FP, demonstrating comparable or even superior performance to established parameters.

Prognostic Utility of Left Atrial Strain to Predict Thrombotic Events and Mortality in Amyloid Cardiomyopathy

BACKGROUND

There is currently no thromboembolic risk stratification tool for amyloid cardiomyopathy (ACM) and the current survival staging systems for ACM have only modest discriminatory ability.

OBJECTIVES

This study aims to evaluate the prognostic value of left atrial (LA) strain to predict incident thrombotic event (TE) and improve survival staging systems in ACM.

METHODS

The authors identified patients with light chain (AL) or transthyretin (ATTR) ACM and no history of atrial fibrillation (AF) at diagnosis. Three components of LA strain (reservoir, conduit, and contractile) were measured and their predictive value for TE and mortality was determined. In addition, the authors evaluated the incremental utility of adding LA strain to current prognostic staging systems.

RESULTS

The authors included 448 patients (50.2% AL; 49.8% ATTR) with median follow-up of 3.8 years. There were 64 (14.3%) TE cases, 103 (23%) AF cases, and 234 (52.2%) deaths. Notably, 75% of TEs occurred without preceding AF documented. LA strain reservoir and LA contractile strain significantly predicted both events: HRs for TE were 2.22 (95% CI: 1.27-3.85; P = 0.006) and 2.63 (95% CI: 1.25-5.00; P = 0.01) per SD decrease in LA strain reservoir and LA contractile strain, respectively. The respective HRs for mortality were 1.32 (95% CI: 1.09-1.59; P < 0.001) and 1.49 (95% CI: 1.22-1.75; P < 0.001). Also, LA strain reservoir and LA contractile strain significantly improved the C-statistics of the Mayo AL staging from 0.65 to 0.68 and 0.70, respectively (P ≤ 0.02); Mayo ATTR staging (0.73 to 0.79 and 0.80, respectively; P < 0.001); and Gillmore ATTR staging (0.70 to 0.79 and 0.80, respectively; P < 0.001).

CONCLUSIONS

LA strain identifies ACM patients with high thrombotic risk (independent of AF) and improves current ACM-specific survival staging.

MMP-2 Associates With Incident Heart Failure and Atrial Fibrillation: The ARIC Study

BACKGROUND

MMP (matrix metalloproteinase)-2 participates in extracellular matrix regulation and may be involved in heart failure (HF), atrial fibrillation (AF), and coronary heart disease.

METHODS

Among the 4693 ARIC study (Atherosclerosis Risk in Communities) participants (mean age, 75±5 years; 42% women) without prevalent HF, multivariable Cox proportional hazard models were used to estimate associations of plasma MMP-2 levels with incident HF, HF with preserved ejection fraction (≥50%), HF with reduced ejection fraction (<50%), AF, and coronary heart disease. Mediation of the association between MMP-2 and HF was assessed by censoring participants who developed AF or coronary heart disease before HF. Multivariable linear regression models were used to assess associations of MMP-2 with measures of left ventricular and left atrial structure and function.

RESULTS

Compared with the 3 lower quartiles, the highest MMP-2 quartile associated with greater risk of incident HF overall (adjusted hazard ratio, 1.48 [95% CI, 1.21-1.81]), incident HF with preserved ejection fraction (1.44 [95% CI, 1.07-1.94]), incident heart failure with reduced ejection fraction (1.48 [95% CI, 1.08-2.02]), and incident AF (1.44 [95% CI, 1.18-1.77]) but not incident coronary heart disease (0.97 [95% CI, 0.71-1.34]). Censoring AF attenuated the MMP-2 association with HF with preserved ejection fraction. Higher plasma MMP-2 levels were associated with larger left ventricular end-diastolic volume index, greater left ventricular mass index, higher E/e' ratio, larger left atrial volume index, and worse left atrial reservoir and contractile strains (all P<0.001).

CONCLUSIONS

Higher plasma MMP-2 levels associate with diastolic dysfunction, left atrial dysfunction, and a higher risk of incident HF and AF. AF is a mediator of MMP-2-associated HF with preserved ejection fraction risk.

Left atrial phasic function: physiology, clinical assessment and prognostic value

Left atrial (LA) phasic function provides significant insights into the pathophysiology of cardiovascular disease. LA function is described in three phases: reservoir (atrial filling, during systole), conduit (passive emptying, during early diastole) and contractile (active emptying, during late diastole). LA phasic function can be evaluated by different imaging modalities, and a variety of techniques including volumetric analysis, deformation (strain) and Doppler methods. LA phasic function (particularly LA reservoir strain) is more sensitive and provides earlier detection of LA dysfunction than alterations in LA volume. LA function parameters have also demonstrated significant diagnostic and prognostic value, particularly in heart failure, atrial fibrillation and stroke. However, there remain barriers to implementation of phasic function parameters in clinical practice and guidelines. This review outlines the physiology of LA phasic function, methods of assessment, and its diagnostic and prognostic utility in varying pathologies.

Influence of exercise training on the left atrium: implications for atrial fibrillation, heart failure, and stroke

The left atrium (LA) plays a critical role in receiving pulmonary venous return and modulating left ventricular (LV) filling. With the onset of exercise, LA function contributes to the augmentation in stroke volume. Due to the growing focus on atrial imaging, there is now evidence that structural remodeling and dysfunction of the LA is associated with adverse outcomes including incident cardiovascular disease. In patients with established disease, pathological changes in atrial structure and function are associated with exercise intolerance, increased hospital admissions and mortality, independent of left ventricular function. Exercise training is widely recommended in patients with cardiovascular disease to improve patient outcomes and maintain functional capacity. There are widely documented changes in LV function with exercise, yet less attention has been given to the LA. In this review, we first describe LA physiology at rest and during exercise, before exploring its association with cardiac disease outcomes including atrial fibrillation, heart failure, and stroke. The adaptation of the LA to short- and longer-term exercise training is evaluated through review of longitudinal studies of exercise training in healthy participants free of cardiovascular disease and athletes. We then consider the changes in LA structure and function among patients with established disease, where adverse atrial remodeling may be implicated in the disease process. Finally, we consider important future directions for assessment of atrial structure and function using novel imaging modalities, in response to acute and chronic exercise.

Early improvement of strain imaging parameters predicts long-term response to sacubitril/valsartan in patients with heart failure with reduced ejection fraction: An observational prospective study

BACKGROUND

Management of patients affected by heart failure with reduced ejection fraction (HFrEF) has deeply changed thanks to novel pharmacological therapies, such as Sacubitril/Valsartan, which assured morbidity and mortality advantages in this population. These effects may be mediated by both left atrial (LA) and ventricular reverse remodeling, although left ventricular ejection fraction (LVEF) recovery still represents the main parameter of treatment response.

METHODS

In this prospective, observational study, 66 patients with HFrEF and naïve from Sacubitril/Valsartan were enrolled. All patients were evaluated at baseline, at 3 months and 12 months from therapy initiation. Echocardiographic parameters, including speckle tracking analysis, LA functional and structural metrics, were collected at three timepoints. The endpoints of our study were: (1) to evaluate the effects of Sacubitril/Valsartan on echo measurements; (2) to assess the predictive role of early modifications of these parameters (expressed as ∆ 3-0 months) on long-term LVEF significant recovery, defined as >15% improvement from baseline.

RESULTS

The majority of echocardiographic parameters evaluated progressively improved during the observation period, including LVEF, ventricular volumes and LA metrics. ∆(3-0 months) of LV Global Longitudinal Strain (LVGLS) and LA Reservoir Strain (LARS) were associated with significant LVEF improvement at 12 months (p < 0.001 and p = 0.019 respectively). A cut-off of ∆(3-0 months) LVGLS of 3% and of ∆(3-0 months) LARS of 2% could predict LVEF recovery with satisfactory sensitivity and specificity.

CONCLUSIONS

LV and LA strain analysis may identify patients who adequately respond to HFrEF medical treatment and should be routinely used in the evaluation of these patients.

Peak atrial longitudinal strain represents atrial fibrillation burden in daily practice: clinical implication of routine left atrial strain measurements

BACKGROUND

Usefulness of left atrial (LA) strain measurements using speckle tracking echocardiography has been reported in various clinical settings. However, clinical implication of routine LA strain measurements in daily practice remains unclear. The purpose of this study was to evaluate clinical utility of routine LA strain measurements in daily practice.

METHODS

From January 6, 2020 to December 28, 2021, 338 consecutive patients underwent echocardiography in Takagi Cardiology Clinic, and all comers were enrolled to the study. Echocardiographic measurements including peak atrial longitudinal strain (PALS) measurement using speckle tracking echocardiography were attempted in all patients.

RESULTS

PALS was obtained in 335 patients (age 71 ± 16 years, male 43%, hypertensive 74%), and mean value was 22.3 ± 11.5%. PALS was progressively impaired with worsening atrial fibrillation (AF) burden. PALS in patients without AF, in patients with history of AF (paroxysmal AF &/or ablation therapy), and in patients with AF onsite were 26.8 ± 9.8%, 20.3 ± 7.9%, and 8.1 ± 3.3%, respectively (anova p < 0.0001). In patients without history of AF at the time of echocardiography, using cut-off value of 15.0% (i.e., mean + 2SD of PALS in AF patients), Kaplan-Meier analysis revealed that impaired PALS was associated with increased new-onset AF during follow-up period (log-rank p < 0.0001).

CONCLUSION

In daily practice, PALS represents AF burden. Furthermore, impaired PALS is associated with increased new-onset AF. Therefore, routine LA strain measurements using speckle tracking echocardiography will be useful in risk stratification of AF in daily practice.

Asymmetric remodeling between the left and right atria in patients with advanced interatrial block and atrial fibrillation

BACKGROUND

Advanced interatrial block (A-IAB) on electrocardiography (ECG) represents the conduction delay between the left and right atria. We investigated the association of A-IAB with left and right atrial (LA/RA) remodeling in patients with atrial fibrillation (AF).

METHODS

We enrolled 74 patients who underwent ECG, cardiac computed tomography (CCT), and echocardiography during sinus rhythm before catheter ablation of AF. A-IAB was defined as P-wave duration ≥120 ms with a biphasic morphology in leads III and aVF or notched morphology in lead II. We compared the maximum and minimum LA/RA volume indices (max and min LAV/RAVI), LA/RA expansion index (LAEI/RAEI), and total, passive, and active LA/RA emptying fraction (LAEF/RAEF) between patients with and without A-IAB.

RESULTS

Of the 74 patients (mean age, 64.3 ± 9.6 years), 35 (47%) showed A-IAB. Patients with A-IAB had a significantly higher likelihood of hypertension and left ventricular diastolic dysfunction than those without. Patients with A-IAB had significantly larger max (69.2 [60.7-79.7]mL/m2 vs. 60.9 [50.4-68.3]mL/m2, P < 0.01) and min (44.0 [37.2-52.1]mL/m2 vs. 34.1 [29.2-43.5]mL/m2, P < 0.01) LAVI than those without. The max and min RAVI were not significantly different between groups. LAEI (55.1 [48.2-78.5]% vs. 72.1 [57.8-84.8]%, P < 0.05), total LAEF (35.5 [32.5-44.0]% vs. 41.9 [36.6-45.9]%, P < 0.05), and passive LAEF (12.2 [10.0-14.4]% vs. 15.5 [11.2-19.6]%, P < 0.05) were significantly lower in patients with A-IAB than without.

CONCLUSIONS

A-IAB was associated with LA, but not RA enlargement, in patients with AF. A-IAB may indicate LA functional remodeling in the reservoir and conduit phases.

Denervation or stimulation? Role of sympatho-vagal imbalance in HFpEF with hypertension

Heart failure (HF) in the elderly is an increasingly large and complex problem in modern society. Notably, the cause of HF with preserved ejection fraction (HFpEF) is multifactorial and its pathophysiology is not fully understood. Among these, hypertension has emerged as a pivotal factor in the pathophysiology and therapeutic targets of HFpEF. Neuronal elements distributed throughout the cardiac autonomic nervous system, from the level of the central autonomic network including the insular cortex to the intrinsic cardiac nervous system, regulate the human cardiovascular system. Specifically, increased sympathetic nervous system activity due to sympatho-vagal imbalance is suggested to be associated the relationship between hypertension and HFpEF. While several new pharmacological therapies, such as sodium-glucose cotransporter 2 inhibitors, have been shown to be effective in HFpEF, neuromodulatory therapies of renal denervation and vagus nerve stimulation (VNS) have received recent attention. The current review explores the pathophysiology of the brain-heart axis that underlies the relationship between hypertension and HFpEF and the rationale for therapeutic neuromodulation of HFpEF by non-invasive transcutaneous VNS.

Defining Heart Failure Based on Imaging the Heart and Beyond

Water and salt retention, in other words congestion, are fundamental to the pathophysiology of heart failure and are important therapeutic targets. Echocardiography is the key tool with which to assess cardiac structure and function in the initial diagnostic workup of patients with suspected heart failure and is essential for guiding treatment and stratifying risk. Ultrasound can also be used to identify and quantify congestion in the great veins, kidneys and lungs. More advanced imaging methods might further clarify the aetiology of heart failure and its consequences for the heart and periphery, thereby improving the efficiency and quality of care tailored with greater precision to individual patient need.

Rationale and design of the Biventricular Evaluation of Gliflozins effects In chroNic Heart Failure: BEGIN-HF study

AIMS

Sodium-glucose cotransporter type 2 inhibitors (SGLT-2i) represent a unique class of anti-hyperglycaemic agents for type 2 diabetes mellitus that selectively inhibit renal glucose reabsorption, thereby increasing urinary excretion of glucose. Several studies have demonstrated the cardioprotective effects of SGLT-2i in patients with heart failure (HF), unrelated to its glucosuric effect. It is unclear whether the benefits of SGLT-2i therapy also rely on the improvement of left ventricular (LV) and/or right ventricular (RV) function in patients with HF. This study aimed to evaluate the effect of SGLT-2i on LV and RV function through conventional and advanced echocardiographic parameters with a special focus on RV function in patients with HF.

METHODS AND RESULTS

The Biventricular Evaluation of Gliflozins effects In chroNic Heart Failure (BEGIN-HF) study is an international multicentre, prospective study that will evaluate the effect of SGLT-2i on echocardiographic parameters of myocardial function in patients with chronic stable HF across the left ventricular ejection fraction (LVEF) spectrum. Patients with New York Heart Association Class II/III symptoms, estimated glomerular filtration rate > 25 mL/min/1.73 m2 , age > 18 years, and those who were not previously treated with SGLT-2i will be included. All patients will undergo conventional, tissue-derived imaging (TDI), and strain echocardiography in an ambulatory setting, at time of enrolment and after 6 months of SGLT-2i therapy. The primary endpoint is the change in LV function as assessed by conventional, TDI, and myocardial deformation speckle tracking parameters. Secondary outcomes include changes in RV and left atrial function as assessed by conventional and deformation speckle tracking echocardiography. Univariate and multivariate analyses will be performed to identify predictors associated with primary and secondary endpoints.

CONCLUSIONS

The BEGIN-HF will determine whether SGLT-2i therapy improves LV and/or RV function by conventional and advanced echocardiography in patients with HF irrespective of LVEF.

Predicting new onset atrial fibrillation post acute myocardial infarction: Echocardiographic assessment of left atrial size

BACKGROUND

Atrial fibrillation (AF) commonly occurs following acute myocardial infarction (AMI). Left atrial (LA) size has been reported to predict new onset AF in this cohort, however, the optimal metric of left atrial size for risk stratification following AMI is unknown.

METHODS

Patients presenting to a tertiary hospital with incident AMI (NSTEMI or STEMI) and no history of AF were recruited. All patients underwent guideline-based workup and management for AMI, including transthoracic echocardiographic assessment. Three alternative metrics of left atrial size were determined: LA area, maximal and minimal LA volume indexed to body surface area (LAVImax and LAVImin). The primary endpoint was new onset AF diagnoses.

RESULTS

Four hundred thirty three patients were included in the analysis, of which 7.1% had a new diagnosis of AF within a median follow-up of 3.8 years. Univariate predictors of incident AF included age, hypertension, revascularization with CABG, NSTEMI presentation, right atrial area, and all three metrics of LA size. Among three multivariable models created for the prediction of new onset AF utilizing alternate metrics of LA size, LAVImin was the only LA size metric found to be an independent predictor.

CONCLUSIONS

LAVImin is an independent predictor of new onset AF post AMI. LAVImin outperforms echocardiographic assessment of diastolic dysfunction and alternative metrics of LA size (including LA area and LAVImax) for risk stratification. Further studies are needed to validate our findings in post AMI patients, and evaluate whether LAVImin holds similar advantages over LAVImax in other cohorts.

Correlation between Heart rate recovery and Left Atrial phasic functions evaluated by 2D speckle-tracking Echocardiography after Acute Myocardial infarction

BACKGROUND

Heart rate recovery (HRR) in the exercise test is the index of cardiac autonomic system function and sympathovagal balance impaired in patients with myocardial infarction (MI). An instance is left atrial (LA) phasic function, which is impaired in such patients. In this study, we investigated the role of HRR in predicting LA phasic functions in patients with MI.

METHODS

The present study recruited 144 consecutive patients with ST-elevation MI. A symptom-limited exercise test was performed about 5 weeks after MI, with echocardiography conducted just before the exercise test. The patients were divided into abnormal and normal HRR at 60 s (HRR60) and again into abnormal and normal HRR at 120 s (HRR120) after the exercise test. LA phasic functions, evaluated by 2D speckle-tracking echocardiography, were compared between the 2 groups.

RESULTS

Patients with abnormal HRR120 had lower LA strain values and strain rates during the reservoir, conduit, and contraction phases, while those with abnormal HRR60 had lower LA strain values and strain rates during the reservoir and conduit phases. The differences were lost after adjustments for possible confounders, except for LA strain and strain rate during the conduit phase, in patients with abnormal HRR120.

CONCLUSIONS

Abnormal HRR120 in the exercise test can independently predict decreased LA conduit function in patients with ST-elevation MI.

Editor-in-Chief's Top Picks From 2022

Each week, I record audio summaries for every paper in JACC, as well as an issue summary. This process has become a true labor of love due to the time they require, but I am motivated by the sheer number of listeners (16 million plus), and it has allowed me to familiarize myself with every paper that we publish. Thus, I have selected the top 100 papers (both Original Investigations and Review Articles) from distinct specialties each year. In addition to my personal choices, I have included papers that have been the most accessed or downloaded on our websites, as well as those selected by the JACC Editorial Board members. In order to present the full breadth of this important research in a consumable fashion, we will present these abstracts in this issue of JACC, as well as their Central Illustrations and podcasts. The highlights comprise the following sections: Basic & Translational Research, Cardiac Failure & Myocarditis, Cardiomyopathies & Genetics, Cardio-Oncology, Congenital Heart Disease, Coronary Disease & Interventions, Coronavirus, Hypertension, Imaging, Metabolic & Lipid Disorders, Neurovascular Disease & Dementia, Promoting Health & Prevention, Rhythm Disorders & Thromboembolism, and Valvular Heart Disease.^1-100.

Reverse Atrial Remodeling in Heart Failure With Recovered Ejection Fraction

Background Heart failure with recovered ejection fraction (HFrecEF) has been a newly recognized entity since 2020. However, the concept has primarily focused on left ventricular ejection fraction improvement, with less focus on the recovery of the left atrium. In this study, we investigated changes in left atrial (LA) echocardiographic indices in HFrecEF. Methods and Results An inpatient cohort with heart failure with reduced ejection fraction (HFrEF) was identified retrospectively and followed up prospectively in a single tertiary hospital. The enrolled patients were classified into HFrecEF and persistent HFrEF groups. Alternations in LA parameters by echocardiography were calculated. The primary outcome was a composite of cardiovascular death or heart failure rehospitalization. A total of 699 patients were included (HFrecEF: n=228; persistent HFrEF: n=471). Compared with persistent HFrEF, the HFrecEF group had greater reductions in LA diameter, LA transverse diameter, LA superior-inferior diameter, LA volume, and LA volume index but not in LA sphericity index. Cox regression analysis showed that the HFrecEF group experienced lower risks of prespecified end points than the persistent HFrEF group after adjusting for confounders. Additionally, 136 (59.6%) and 62 (13.0%) patients showed LA reverse remodeling (LARR) for the HFrecEF and persistent HFrEF groups, respectively. Among the HFrecEF subgroup, patients with LARR had better prognosis compared with those without LARR. Multivariate logistic analysis demonstrated that age and coronary heart disease were 2 independent negative predictors for LARR. Conclusions In HFrecEF, both left ventricular systolic function and LA structure remodeling were improved. Patients with HFrecEF with LARR had improved clinical outcomes, indicating that the evaluation of LA size provides a useful biomarker for risk stratification of heart failure.

Prediction of congestive state in acute and chronic heart failure: The association between NT-proBNP and left atrial strain and its prognostic value

BACKGROUND

The relief of congestion is crucial to improve heart failure (HF) patient's quality of life and prognosis. N-terminal-pro-brain natriuretic peptide (NT-proBNP) is a well-known marker of congestion, although with limited specificity. Peak atrial longitudinal strain (PALS) by speckle tracking echocardiography (STE) is an index of intracardiac pressure and HF prognosis. We aimed to determine the association between NT-proBNP and PALS and its prognostic implications in patients with HF.

METHODS

Patients hospitalized for de-novo or recurrent HF and outpatients with chronic HF were included in this retrospective study. Patients with missing data, previous cardiac surgery, non-feasible STE were excluded. Clinical, laboratory and echocardiographic data were collected. STE was performed on echocardiographic records. Primary endpoint was a combination of all-cause death and HF hospitalization.

RESULTS

Overall, 388 patients were included (172 acute HF, 216 chronic HF, mean age = 65 ± 12 years, 37% female). Mean LV ejection fraction = 31 ± 9%. Global PALS showed a significant inverse correlation with NT-proBNP in acute and chronic HF (all p < 0.001). During a median follow-up of 4 years, 180 patients reached the combined endpoint. NT-proBNP (AUC = 0.87) and global PALS (AUC = 0.82) were good predictors of the combined endpoint. Global PALS was the only independent predictor of the combined endpoint. Optimal risk stratification for the composite endpoint was provided combining PALS ≤15% and NTproBNP ≥874.5 ng/l.

CONCLUSIONS

Global PALS is associated with NT-proBNP in acute and chronic HF and may be used as additional index of congestion to optimize therapeutic management. The combination of global PALS and NT-proBNP could enhance the prognostic stratification of HF.