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

Left Atrial Mechanical Dysfunction and the Risk for Ischemic Stroke in People Without Prevalent Atrial Fibrillation or Stroke : A Prospective Cohort Study

BACKGROUND

Atrial myopathy-characterized by changes in left atrial function and size-may precede and promote atrial fibrillation (AF) and cardiac thromboembolism. In people without prior AF or stroke, whether analysis of left atrial function and size can improve ischemic stroke prediction is unknown.

OBJECTIVE

To evaluate the association of echocardiographic left atrial function (reservoir, conduit, and contractile strain) and left atrial size (left atrial volume index) with ischemic stroke and determine whether these measures can improve the stroke prediction achieved by CHA2DS2-VASc score variables.

DESIGN

Prospective cohort study.

SETTING

ARIC (Atherosclerosis Risk in Communities) study.

PARTICIPANTS

4917 ARIC participants without prevalent stroke or AF.

MEASUREMENTS

Ischemic stroke events (2011 to 2019) were adjudicated by physicians. Left atrial strain was measured using speckle-tracking echocardiography.

RESULTS

Over 5 years, the cumulative incidences of ischemic stroke in the lowest quintiles of left atrial reservoir, conduit, and contractile strain were 2.99% (95% CI, 1.89% to 4.09%), 3.18% (CI, 2.14% to 4.22%), and 2.15% (CI, 1.09% to 3.21%), respectively, and that of severe left atrial enlargement was 1.99% (CI, 0.23% to 3.75%). On the basis of the Akaike information criterion, left atrial reservoir strain plus CHA2DS2-VASc variables was the best predictive model. With the addition of left atrial reservoir strain to CHA2DS2-VASc variables, 11.6% of the 112 participants with stroke after 5 years were reclassified to higher risk categories and 1.8% to lower risk categories. Among the 4805 participants who did not develop stroke, 12.2% were reclassified to lower and 12.7% to higher risk categories. Decision curve analysis showed a predicted net benefit of 1.34 per 1000 people at a 5-year risk threshold of 5%.

LIMITATION

Underascertainment of subclinical AF.

CONCLUSION

In people without prior AF or stroke, when added to CHA2DS2-VASc variables, left atrial reservoir strain improves stroke prediction and yields a predicted net benefit, as shown by decision curve analysis.

PRIMARY FUNDING SOURCE

National Heart, Lung, and Blood Institute of the National Institutes of Health.

Spironolactone effect on cardiac structure and function of patients with heart failure and preserved ejection fraction: a pooled analysis of three randomized trials

AIMS

Spironolactone is currently used in a large proportion of patients with heart failure and preserved ejection fraction (HFpEF), yet its effect on cardiac structure and function in a large population has not been well established. The aim of this study was to evaluate the impact of spironolactone on key echocardiographic parameters in HFpEF.

METHODS AND RESULTS

An individual-patient-data meta-analysis of three randomized trials (HOMAGE, Aldo-DHF, and TOPCAT) was performed comparing spironolactone (9-12 month exposure) to placebo (or control) for the changes in left atrial volume index (LAVi), left ventricular mass index (LVMi), interventricular septum (IVS) thickness, E/e' ratio, and left ventricular ejection fraction (LVEF) among patients with stage B (HOMAGE) or C (Aldo-DHF and TOPCAT) HFpEF. Analysis of covariance was used to test the effect of spironolactone on echocardiographic changes. A total of 984 patients were included in this analysis: 452 (45.9%) from HOMAGE, 398 (40.4%) from Aldo-DHF, and 134 (13.6%) from TOPCAT. The pooled-cohort patient's median age was 71 (66-77) years and 39% were women. Median LAVi was 29 (24-35) ml/m² , LVMi 100 (84-118) g/m² , IVS thickness 12 (10-13) mm, E/e' ratio 11 (9-13), and LVEF 64 (59-69)%. Spironolactone reduced LAVi by -1.1 (-2.0 to -0.1) ml/m² (p = 0.03); LVMi by -3.6 (-6.4 to -0.8) g/m² (p = 0.01); IVS thickness by -0.2 (-0.3 to -0.1) mm (p = 0.01); E/e' ratio by -1.3 (-2.4 to -0.2) (p = 0.02); and increased LVEF by 1.7 (0.8-2.6)% (p < 0.01). No treatment-by-study heterogeneity was found except for E/e' ratio with a larger effect in Aldo-DHF and TOPCAT (interaction p < 0.01).

CONCLUSIONS

Spironolactone improved cardiac structure and function of patients with HFpEF.

Left Atrial Strain for Assessment of Left Ventricular Diastolic Function: Focus on Populations with Normal LVEF

Left atrial (LA) strain has emerged as a useful parameter for the assessment of left ventricular (LV) diastolic function and the estimation of LV filling pressures. Some have advocated using LA strain by itself, mainly reservoir strain, as a single stand-alone measurement for this objective. Recent data indicate several challenges for this application in patients with normal left ventricular ejection fraction (LVEF) because of the wide range for normal values and the load dependency of LA strain. Both findings can result in reduced left atrial reservoir strain (LARS) values in normal subjects that overlap those seen in patients with diastolic dysfunction. LARS for the estimation of LV filling pressures is most accurate in patients with depressed LVEF. It is less accurate in patients with normal ejection fraction. In this group of patients, LARS <18% has high specificity for increased LV filling pressures. There are promising data showing the association of LARS with outcome events in patients with normal ejection fraction, and additional data are needed to confirm that it provides incremental information over clinical and other echocardiographic measurements.

Three-Dimensional Automated, Machine-Learning-Based Left Heart Chamber Metrics: Associations with Prevalent Vascular Risk Factors and Cardiovascular Diseases

Background. Three-dimensional transthoracic echocardiography (3DE) powered by artificial intelligence provides accurate left chamber quantification in good accordance with cardiac magnetic resonance and has the potential to revolutionize our clinical practice. Aims. To evaluate the association and the independent value of dynamic heart model (DHM)-derived left atrial (LA) and left ventricular (LV) metrics with prevalent vascular risk factors (VRFs) and cardiovascular diseases (CVDs) in a large, unselected population. Materials and Methods. We estimated the association of DHM metrics with VRFs (hypertension, diabetes) and CVDs (atrial fibrillation, stroke, ischemic heart disease, cardiomyopathies, >moderate valvular heart disease/prosthesis), stratified by prevalent disease status: participants without VRFs or CVDs (healthy), with at least one VRFs but without CVDs, and with at least one CVDs. Results. We retrospectively included 1069 subjects (median age 62 [IQR 49−74]; 50.6% women). When comparing VRFs with the healthy, significant difference in maximum and minimum indexed atrial volume (LAVi max and LAVi min), left atrial ejection fraction (LAEF), left ventricular mass/left ventricular end-diastolic volume ratio, and left ventricular global function index (LVGFI) were recorded (p < 0.05). In the adjusted logistic regression, LAVi min, LAEF, LV ejection fraction, and LVGFI showed the most robust association (OR 3.03 [95% CI 2.48−3.70], 0.45 [95% CI 0.39−0.51], 0.28 [95% CI 0.22−0.35], and 0.22 [95% CI 0.16−0.28], respectively, with CVDs. Conclusions. The present data suggested that novel 3DE left heart chamber metrics by DHM such as LAEF, LAVi min, and LVGFI can refine our echocardiographic disease discrimination capacity.

Long-term prognostic value of left atrial longitudinal strain in an elderly community-based cohort

Despite the well-known importance of left atrial (LA) mechanics in diastolic function, data are scarce regarding the prognostic power of LA longitudinal strain and its potential added value in the risk stratification of an elderly population. Accordingly, our aim was to determine the long-term prognostic importance of 2D speckle-tracking echocardiography-derived peak atrial longitudinal strain (PALS) in a community-based screening sample. Three hundred and fourteen volunteers were retrospectively identified from a population-based screening program (mean age 62 ± 11 years; 58% female) with a median follow-up of 9.5 years. All subjects who participated in the screening program underwent 2D echocardiography to measure left ventricular (LV) ejection fraction (EF), global longitudinal strain (GLS), and PALS, as well as low-dose cardiac CT to determine the Agatston score. The primary endpoint was all-cause mortality. Thirty-nine subjects (12.4%) met the primary endpoint. Subjects with adverse outcomes had significantly lower LV GLS (dead vs. alive; - 19.2 ± 4.3 vs. - 20.6 ± 3.5%, p < 0.05) and PALS (32.3 ± 12.0 vs. 41.8 ± 14.2%, p < 0.001), whereas LV EF did not show a difference between the two groups (51.1 ± 7.0 vs. 52.1 ± 6.2, %, p = NS). By multivariable Cox regression analysis, PALS was found to be a significant predictor of adverse outcomes independent of LV GLS, and Agatston and Framingham scores. In subjects with PALS values below the standard cut-off of 39%, the risk of all-cause mortality was almost 2.5 times higher (hazard ratio: 2.499 [95% confidence interval: 1.334-4.682], p < 0.05). Beyond the assessment of LV EF and LV GLS, PALS offers incremental value in cardiovascular risk stratification in a community-based elderly cohort. PALS was found to be a significant and independent predictor of long-term mortality among other classical cardiovascular risk estimators.

Clinical implications of left atrial changes after optimization of medical therapy in patients with heart failure

AIMS

Limited data exist regarding the prognostic relevance of changes in left atrial (LA) dimensions in patients with heart failure (HF). We assessed changes in LA dimension and their relation with outcomes after optimization of guideline-directed medical therapy (GDMT) in patients with new-onset or worsening HF.

METHODS AND RESULTS

Left atrial diameter was assessed at baseline and 9 months after GDMT optimization in 632 patients (mean age 65.8 ± 12.1 years, 22.3% female) enrolled in BIOSTAT-CHF. LA adverse remodelling (LAAR) was defined as an increase in LA diameter on transthoracic echocardiography between baseline and 9 months. After the 9-month visit, patients were followed for a median of 13 further months. LAAR was observed in 247 patients (39%). Larger baseline LA diameter (odds ratio [OR] 0.90; 95% confidence interval [CI] 0.87-0.93; p < 0.001) and up-titration to higher doses of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ACEi/ARBs) (OR 0.56; 95% CI 0.34-0.92; p = 0.022) were independently associated with lower likelihood of LAAR. LAAR was associated with an increased risk of the composite of all-cause mortality or HF hospitalization (log-rank p = 0.007 and adjusted hazard ratio 1.73, 95% CI 1.22-2.45, p = 0.002). The association was more pronounced in patients without a history of atrial fibrillation (p for interaction = 0.009).

CONCLUSION

Among patients enrolled in BIOSTAT-CHF, LAAR was associated with an unfavourable outcome and was prevented by ACEi/ARB up-titration. Changes in LA dimension may be a useful marker of response to treatment and improve risk stratification in patients with HF.

Subclinical HMOD in Hypertension: Left Ventricular Diastolic Dysfunction

Arterial hypertension represents an important risk factor for the development of cardiac, vascular and renal events, predisposing to heart failure, acute coronary syndromes, peripheral artery disease, stroke, and chronic renal disease. Arterial hypertension leads to the development of subclinical hypertension mediated organ damage (HMOD) which has prognostic relevance and may influence the choice of treatment options. Alterations of cardiac structure and function represent the more widely assessed form of HMOD. This manuscript will focus on the diagnostic opportunities, prognostic significance and treatment of diastolic dysfunction alterations.

Update on Hypertension Research in 2021

In 2021, 217 excellent manuscripts were published in Hypertension Research. Editorial teams greatly appreciate the authors' contribution to hypertension research progress. Here, our editorial members have summarized twelve topics from published work and discussed current topics in depth. We hope you enjoy our special feature, "Update on Hypertension Research in 2021".

Left atrial disease and left atrial reverse remodelling across different stages of heart failure development and progression: a new target for prevention and treatment

The left atrium is a dynamic chamber with peculiar characteristics. Stressors and disease mechanisms may deeply modify its structure and function, leading to left atrial remodelling and disease. Left atrial disease is a predictor of poor outcomes. It may be a consequence of left ventricular systolic and diastolic dysfunction and neurohormonal and inflammatory activation and/or actively contribute to the progression and clinical course of heart failure through multiple mechanisms such as left ventricular filling and development of atrial fibrillation and subsequent embolic events. There is growing evidence that therapy may improve left atrial function and reverse left atrial remodelling. Whether this translates into changes in patient's prognosis is still unknown. In this review we report current data about changes in left atrial size and function across different stages of development and progression of heart failure. At each stage, drug therapies, lifestyle interventions and procedures have been associated with improvement in left atrial structure and function, namely a reduction in left atrial volume and/or an improvement in left atrial strain function, a process that can be defined as left atrial reverse remodelling and, in some cases, this has been associated with improvement in clinical outcomes. Further evidence is still needed mainly with respect of the possible role of left atrial reverse remodelling as an independent mechanism affecting the patient's clinical course and as regards better standardization of clinically meaningful changes in left atrial measurements. Summarizing current evidence, this review may be the basis for further studies.