Doppler transmitral flow indexes and risk of atrial fibrillation (the Framingham Heart Study)

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.

Atrial Fibrillation, Atrial Myopathy, and Thromboembolism: The Additive Value of Echocardiography and Possible New Horizons for Risk Stratification

Atrial fibrillation (AF) is the most common cardiac sustained arrhythmia, and it is associated with increased stroke and dementia risk. While the established paradigm attributes these complications to blood stasis within the atria and subsequent thrombus formation with cerebral embolization, recent evidence suggests that atrial myopathy (AM) may play a key role. AM is characterized by structural and functional abnormalities of the atria, and can occur with or without AF. Moving beyond classifications based solely on episode duration, the 4S-AF characterization has offered a more comprehensive approach, incorporating patient's stroke risk, symptom severity, AF burden, and substrate assessment (including AM) for tailored treatment decisions. The "ABC" pathway emphasizes anticoagulation, symptom control, and cardiovascular risk modification and emerging evidence suggests broader benefits of early rhythm control strategies, potentially reducing stroke and dementia risk and improving clinical outcomes. However, a better integration of AM assessment into the current framework holds promise for further personalizing AF management and optimizing patient outcomes. This review explores the emerging concept of AM and its potential role as a risk factor for stroke and dementia and in AF patients' management strategies, highlighting the limitations of current risk stratification methods, like the CHA2DS2-VASc score. Echocardiography, particularly left atrial (LA) strain analysis, has shown to be a promising non-invasive tool for AM evaluation and recent studies suggest that LA strain analysis may be a more sensitive risk stratifier for thromboembolic events than AF itself, with some studies showing a stronger association between LA strain and thromboembolic events compared to traditional risk factors. Integrating it into routine clinical practice could improve patient management and targeted therapies for AF and potentially other thromboembolic events. Future studies are needed to explore the efficacy and safety of anticoagulation in AM patients with and without AF and to refine the diagnostic criteria for AM.

Atrial cardiomyopathy: Current and future imaging methods for assessment of atrial structure and function

Changes in atrial size and function have historically been considered a surrogate marker of ventricular dysfunction. However, it is now recognized that atrial cardiomyopathy (ACM) may also occur as a primary myocardial disorder. Emerging evidence that ACM is a major risk factor for atrial fibrillation, heart failure, and thromboembolic stroke, has highlighted the significance of this disorder and the need for better assessment of atrial metrics in clinical practice. Key barriers in this regard include a lack of standardized criteria or hierarchy for the diagnosis of ACM and lack of consensus for the most accurate phenotyping methods. In this article we review existing literature on ACM, with a focus on current and future non-invasive imaging methods for detecting abnormalities of atrial structure and function. We discuss the relative advantages and disadvantages of transthoracic echocardiography and cardiac magnetic resonance imaging for assessing a range of parameters, including atrial size and contractile function, strain, tissue characteristics, and epicardial adipose tissue. We will also present the potential application of novel imaging methods such as sphericity index and four- or five-dimensional flow.

E/e' Ratio Predicts the Atrial Pacing-Induced Left Atrial Pressure Response in Patients with Preserved Ejection Fraction

Background and Objectives: Left atrial hypertension is one of the pathophysiologies of heart failure with preserved ejection fraction. We hypothesized that left atrial pressure response (LAPR) to incremental pacing is higher in patients with atrial fibrillation (AF) and can predict left ventricular diastolic dysfunction. Materials and Methods: Patients requiring left atrial access as a part of a therapeutic procedure for AF (n = 204, AF group) or supraventricular tachycardia (n = 34, control group) were analyzed (male n = 183, 54 ± 12 years old). LAPR was measured during incremental pacing. Results: Baseline left atrial pressure and LAPR at all pacing rates were not different between the AF and control groups. They were higher in patients with a high E/e' (≥ 8) than in those with a low E/e' (<8). LAPR at a pacing interval of 400 ms and E/e' were positively correlated (r = 0.373, p < 0.001). Body mass index and a high E/e' were independent predictors of pacing-induced left atrial hypertension. Conclusions: LAPR to incremental pacing was constant regardless of AF. The non-invasive echocardiographic marker E/e' reflected pacing-induced left atrial hypertension.

Prognostic significance of diastolic dysfunction in patients with systolic dysfunction undergoing atrial fibrillation ablation

Background

The relationship between pre-ablation left ventricular diastolic dysfunction (LVDD) and prognosis in patients with left ventricular systolic dysfunction (LVSD) undergoing atrial fibrillation (AF) ablation remains unclear.

Methods

The prognosis of 173 patients with impaired left ventricular ejection fraction (<50%) who underwent AF ablation was examined. The primary outcome was a composite of all-cause mortality, heart failure (HF) hospitalization, and worsening HF symptoms requiring unplanned outpatient intensification of decongestive therapy.

Results

During the follow-up period (median, 3.5 years), the primary outcome after AF ablation occurred in 28 patients (16%). The receiver operating characteristic curve analysis showed that early septal diastolic mitral annular velocity (e′) had a larger area under the curve (0.70) than other LVDD parameters, and optimal cut-off values of LVDD, represented by e′, septal E (early diastolic left ventricular filling velocity)/e′, and peak tricuspid valve regurgitation velocity (TRV), were 5.0 cm/s, 13.2, and 2.5 m/s, respectively. Multivariate analysis revealed that e′ ≤5.0 cm/s (standard hazard ratio [HR], 3.87; 95% confidence interval [CI], 1.73–8.69; p = 0.001), septal E/e′ ≥13.2 (HR, 3.62; 95% CI, 1.60–8.21; p = 0.002), and peak TRV ≥ 2.5 m/s (HR, 2.42; 95% CI, 1.13–5.16; p = 0.02) independently predicted the outcome. Patients with New York Heart Association functional status ≥ III had a 3.3–4.5-fold higher risk of the outcome.

Conclusions

LVDD or severe HF symptoms predict poor outcomes in patients with LVSD undergoing AF ablation. Therefore, patients with LVDD or severe HF symptoms should receive more intensive treatment even after AF ablation.

Left Atrial Cardiomyopathy - A Challenging Diagnosis

Left atrial cardiomyopathy (LACM) has been an ongoing focus of research for several years. There is evidence that LACM is responsible for atrial fibrillation and embolic strokes of undetermined sources. Therefore, the correct diagnosis of LACM is of clinical importance. Various techniques, including electrocardiography, echocardiography, cardiac magnetic resonance imaging, computed tomography, electroanatomic mapping, genetic testing, and biomarkers, can both identify and quantify structural, mechanical as well as electrical dysfunction in the atria. However, the question arises whether these techniques can reliably diagnose LACM. Because of its heterogeneity, clinical diagnosis is challenging. To date, there are no recommendations for standardized diagnosis of suspected LACM. However, standardization could help to classify LACM more precisely and derive therapeutic directions to improve individual patient management. In addition, uniform diagnostic criteria for LACM could be important for future studies. Combining several parameters and relating them seems beneficial to approach the diagnosis of LACM. This review provides an overview of the current evidence regarding the diagnosis of LACM, in which several potential parameters are discussed and, consequently, a proposal for a diagnostic algorithm is presented.

A Review of the Role of Transthoracic and Transesophageal Echocardiography, Computed Tomography, and Magnetic Resonance Imaging in Cardioembolic Stroke

Stroke is a major source of morbidity and mortality worldwide, accounting for the second largest cause of mortality and the third greatest cause of disability. Stroke is frequently preceded by a transient ischemic attack (TIA). The etiologies of 20-30% of ischemic strokes are unknown, and thus are termed "cryptogenic strokes". About 25% of ischemic strokes are cardioembolic. Strokes occur at a rate of around 2% per year in individuals with heart failure with reduced ejection fraction (HFrEF), with a strong correlation between stroke risk and the degree of ventricular impairment. Furthermore, stroke risk is augmented in the absence of anticoagulation therapy. Cardioembolic strokes, when treated inadequately, have a greater predilection for recurrences than atherothrombotic strokes, both early and late in life. The role of a patent foramen ovale in strokes, specifically in "cryptogenic strokes", is a matter of concern that deserves due attention. The use of tissue-engineered heart valves and aspirin for minimizing the risk of stroke is recommended. Transthoracic echocardiography (TTE) is advantageous for assessing heart function in the acute phase of ischemic stroke. Transesophageal echocardiography (TEE) is considered the criterion standard procedure for detecting LAA thrombi. Computed tomography (CT) scans are good imaging modalities for identifying and excluding bleeding. Magnetic resonance imaging (MRI) images are by far the most effective imaging technique available for assessing the brain parenchymal state. We conducted a thorough review of the literature on the use of imaging modalities, highlighting the important contribution of TTE, TEE, CT, and MRI in the evaluation of cardioembolic stroke.

Association between angiopoietin-2 and functional cardiac remodeling in hemodialysis patients with normal left ventricular ejection

Cardiac remodeling is the initial process in heart failure development. The aim of this study is to evaluate the association between endothelium-related biomarkers and cardiac remodeling in hemodialysis (HD) patients and how the presence of high blood pressure and diabetes mellitus modulates these associations. This was a cross-sectional study with adult HD and normal left ventricular (LV) ejection fraction-LVEF-patients. The authors correlated several endothelium-related biomarkers with echocardiographic indices-LV mass index (LVMi), LVEF, global longitudinal strain, mitral E/e', and aortic root diameter. Seventy-one patients were included, with 37 women (52.1%) and mean age of 54.3 ± 16.8 years. Angiopoietin-2 (AGPT2) was inversely correlated with global longitudinal strain (r = -.374, p = .001) and directly with E/e' (r = .265, p = .025). After adjustment, only AGPT2 was significantly associated with global longitudinal strain. blood pressure and diabetes mellitus were independent moderators for the AGPT2 and global longitudinal strain association. The conditional association was significant only when the mean pre-HD blood pressure was above 97.5 mmHg or in diabetes mellitus patients. Finally, there was an interaction between diabetes mellitus and blood pressure when moderating the conditional effect of AGPT2 on global longitudinal strain. While in non-diabetic patients, the association between AGPT2 with global longitudinal strain was significant only with pre-HD blood pressure levels as high as 110 mmHg, in diabetic patients, this association was significant with pre-HD blood pressure as low as 90 mmHg. Higher levels of AGPT2 were associated with worse cardiac function as determined by lower global longitudinal strain values. This association was moderated by blood pressure and diabetes mellitus, suggesting that the effects of AGPT2 on cardiac remodeling is dependent of such circumstances.

Advances in Multimodality Cardiovascular Imaging in the Diagnosis of Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a syndrome defined by the presence of heart failure symptoms and increased levels of circulating natriuretic peptide (NP) in patients with preserved left ventricular ejection fraction and various degrees of diastolic dysfunction (DD). HFpEF is a complex condition that encompasses a wide range of different etiologies. Cardiovascular imaging plays a pivotal role in diagnosing HFpEF, in identifying specific underlying etiologies, in prognostic stratification, and in therapeutic individualization. Echocardiography is the first line imaging modality with its wide availability; it has high spatial and temporal resolution and can reliably assess systolic and diastolic function. Cardiovascular magnetic resonance (CMR) is the gold standard for cardiac morphology and function assessment, and has superior contrast resolution to look in depth into tissue changes and help to identify specific HFpEF etiologies. Differently, the most important role of nuclear imaging [i.e., planar scintigraphy and/or single photon emission CT (SPECT)] consists in the screening and diagnosis of cardiac transthyretin amyloidosis (ATTR) in patients with HFpEF. Cardiac CT can accurately evaluate coronary artery disease both from an anatomical and functional point of view, but tissue characterization methods have also been developed. The aim of this review is to critically summarize the current uses and future perspectives of echocardiography, nuclear imaging, CT, and CMR in patients with HFpEF.

Echocardiographic predictors of cardioembolic stroke due to underlying atrial fibrillation: Reliable left atrial remodeling signs in acute stroke

INTRODUCTION

Atrial remodeling due to high-burden atrial fibrillation (AF) is associated with cardioembolic stroke (CES). As not all CESs is caused by AF, we analyzed the diagnostic values of each echocardiographic parameter to distinguish likely AF-related CES in acute stroke patients while in non-AF rhythm.

METHODS

The data of consecutive patients with acute ischemic stroke in sinus rhythm between 2012 and 2015 were obtained. The echocardiographic parameters of patients with CES due to underlying AF (n = 61) and control patients (n = 319) with either large artery atherosclerosis or small-vessel occlusion were compared using receiver operating characteristic curves and logistic regression analyses. Each parameter was reassessed in acute stroke patients through a validation study using the same database with different periods of generalization.

RESULTS

CES patients with underlying AF showed a significantly larger left atrial volume index (LAVi), higher mitral inflow E wave (E), and lower A wave (A) than the controls. The area under the curve (AUC) (95% confidence interval) for diagnosing CES due to underlying AF was significantly higher for LAVi/A than for LAVi (0.785 versus 0.696, P < 0.01). Among patients aged >60 years, the E/A ratio had the highest AUC (0.857) of the parameters. The cut-off values were ≥ 0.70 (sensitivity, 55.7%; specificity, 90.9%) and ≥ 0.82 (sensitivity, 71.4%; specificity, 84.1%) for LAVi/A and the E/A ratio, respectively, in patients >60 years. The cut-off values of all parameters showed similar trends in a validation study.

CONCLUSION

LAVi/A is a useful indicator for distinguishing CES patients with underlying AF regardless of age, and the E/A ratio is reliable among patients aged >60 years in evaluation during acute stroke admission.

Atrial fibrillation and atrial cardiomyopathies

Atrial fibrillation (AF) is the most common arrhythmia among adults. While there have been incredible advances in the management of AF and its clinical sequelae, investigation of atrial cardiomyopathies (ACMs) is becoming increasingly more prominent. ACM refers to the electromechanical changes-appreciated subclinically and/or clinically-that underlie atrial dysfunction and create an environment ripe for the development of clinically apparent AF. There are several subtypes of ACM, distinguished by histologic features. Recent progress in cardiovascular imaging, including echocardiography with speckle-tracking (e.g., strain analysis), cardiovascular magnetic resonance imaging (CMR), and atrial 4-D flow CMR, has enabled increased recognition of ACM. Identification of ACM and its features carry clinical implications, including elevating a patient's risk for development of AF, as well as associations with outcomes related to catheter-based and surgical AF ablation. In this review, we explore the definition and classifications of ACM, its complex relationship with clinical AF, imaging modalities, and clinical implications. We propose next steps for a more unified approach to ACM recognition that can direct further research into this complex field.

Diastolic function assessed with speckle tracking over a decade and its prognostic value: The Copenhagen City Heart Study

BACKGROUND

The ratio of transmitral early filling velocity to early diastolic strain rate (E/e'sr) may be a more accurate measure of LV filling pressure then ratio of early filling pressure to early tissue velocity. The aim of the study was to investigate the impact of age, sex, obesity, smoking, hypertension, hypercholesterolemia, diabetes, physical activity level, socioeconomic, and psychosocial status on E/e'sr over a decade. Additionally, the predictive value of ΔE/e'sr on future major adverse cardiovascular events (MACE) has never been explored.

METHOD

The study included 623 participants from the general population, who participated in the 4th and 5th Copenhagen City Heart Study (CCHS4 and CCHS5). Examinations were median 10 years apart. MACE was the composite endpoint of heart failure, myocardial infarction, and all-cause death.

RESULTS

Follow-up time was median 5.7 years, and 43 (7%) experienced MACE. Mean age was 51 ± 14 years, and 43% were male. Mean ΔE/e'sr was 2.1 ± 23.0 cm. After multivariable adjustment for demographic, clinical, and biochemistry variables, high age (stand. β-coef. = .24, P < .001) and mean arterial blood pressure (MAP) (stand. β-coef. = .17, P < .001) were significantly associated with an accelerated increase in E/e'sr In multivariable Cox regression, E/e'sr at CCHS5 and ΔE/e'sr were independent predictors of MACE (HR = 1.20, 95% CI [1.01; 1.42] per 10 cm increase for both). ΔE/e'sr did only provide incremental prognostic value to change in left atrial volume index of the conventional diastolic measurements.

CONCLUSION

In the general population, age and MAP were predictors of an accelerated increase in E/e'sr over a decade. E/e'sr at CCHS5 and ΔE/e'sr were independent predictors of future MACE.

Left Atrial Myopathy in Atrial Fibrillation and Heart Failure: Clinical Implications, Mechanisms, and Therapeutic Targets

PURPOSE OF REVIEW

This review discusses the mechanisms, clinical implications, and treatments of left atrial (LA) myopathy in comorbid atrial fibrillation (AF) and heart failure (HF) across the spectrum of ejection fraction.

RECENT FINDINGS

AF and HF are highly comorbid conditions. Left atrial (LA) myopathy, characterized by impairments in LA structure, function, or electrical conduction, plays a fundamental role in the development of both AF and HF with preserved ejection fraction (AF-HFpEF) along with AF and HF with reduced ejection fraction (AF-HFrEF). While the nature of LA myopathy in AF-HFpEF is unique from that of AF-HFrEF, LA myopathy also leads to progression of both of these conditions. There may be a vulnerable cohort of AF-HF patients who have a disproportionate degree of LA myopathy compared with left ventricular (LV) dysfunction. Further investigations are required to identify therapies to improve LA function in this cohort.

Circulating growth factors and cardiac remodeling in the community: The Framingham Heart Study

BACKGROUND AND AIMS

Cardiac and vascular growth factors (GF) may influence myocardial remodeling through cardiac growth and angiogenic effects. We hypothesized that concentrations of circulating GF are associated with cardiac remodeling traits.

METHODS

We related blood concentrations of vascular endothelial GF (VEGF), VEGFR-1 (sFlt1), angiopoietin 2 (Ang-2), soluble angiopoietin type-2 receptor (sTie2), hepatocyte GF (HGF), insulin-like GF (IGF)-1, IGF binding protein (IGFBP)-3, and growth differentiation factor-15 (GDF-15) to echocardiographic traits in 3151 Framingham Study participants (mean age 40 years, 55% women). We evaluated the following measures: left ventricular (LV) mass index (LVMi), LV ejection fraction (LVEF), global longitudinal strain (GLS), mitral E/e', and aortic root diameter (AoR). All biomarker values were sex-standardized.

RESULTS

In multivariable-adjusted analyses, higher GDF-15 concentrations were associated with higher log-LVMi (β = 0.009 per SD, P = 0.01). Similarly, sTie2 concentrations were positively associated with log-E/e' (β = 0.011 per SD, P = 0.04). IGF-1 and Ang-2 concentrations were positively and negatively associated with GLS, respectively (βIGF-1 = 0.16 per SD and βAng-2 = -0.15 per SD, both P < 0.05), whereas higher sFlt1 and Ang-2 levels were associated with smaller log-AoR (βsFlt1 = -0.004 per SD and β Ang-2 = -0.005 per SD, respectively; P < 0.05).

CONCLUSION

In our large community-based sample, we observed patterns of associations between several circulating vascular GF and cardiac remodeling indices that are consistent with the known biological effects of these pro- and anti-angiogenic factors on the myocardium and conduit arteries. Additional studies are warranted to replicate our findings and assess their prognostic significance.

The Investigation of Left Atrial Structure and Stroke Etiology: The I-LASER Study

Background Left atrial (LA) function is important in stroke, but often poorly characterized. We evaluated the association of 2-dimensional speckle tracking echocardiography LA variables with stroke subtype (cardioembolic stroke [CS] or cryptogenic stroke versus other). The hypothesis is worse LA active function is associated with CS, but not cryptogenic strokes. Methods and Results In this prospective cohort (2017-2019), left ventricular/LA structure and function were quantified by 2-dimensional and speckle tracking echocardiography in 151 patients with stroke. Strain/strain rate curves for the 3 components of the LA cycle, ie, (1) Reservoir (global longitudinal strain [Srmax]), (2) Conductive (early LA Sr [Sre]), and (3) Active (late LA strain [Sra]) were evaluated, masked to stroke subtype. Associations of cardiac features with stroke subtype were tested using multivariable logistic regressions. Odds of CS were increased in patients with a larger LA systolic diameter (odds ratio [OR], 2.96, 95% CI, 1.14-7.69) but reduced in patients with a higher Srmax (better reservoir) (OR, 0.80, 95% CI, 0.67-0.97). Lower Sra (worse function) was associated with an increased odds of CS (OR, 1.72, 95% CI, 1.07-2.76) but not independent of atrial fibrillation. Higher active LA emptying fraction (better active phase) was associated with reduced odds of CS (OR, 0.74, 95% CI, 0.57-0.95) or cryptogenic stroke (OR, 0.82, 95% CI, 0.68-0.98) versus other subtypes; other associations between cryptogenic stroke and speckle tracking echocardiography were not found. Conclusions Markers of LA structure and function were associated with CS. Similar associations were not found for cryptogenic stroke, which might suggest different underlying mechanisms, given study limitations. Further understanding could aid stroke diagnosis and secondary stroke prevention research.

Multicohort Metabolomics Analysis Discloses 9-Decenoylcarnitine to Be Associated With Incident Atrial Fibrillation

Background The molecular mechanisms involved in atrial fibrillation are not well known. We used plasma metabolomics to investigate if we could identify novel biomarkers and pathophysiological pathways of incident atrial fibrillation. Methods and Results We identified 200 endogenous metabolites in plasma/serum by nontargeted ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry in 3 independent population-based samples (TwinGene, n=1935, mean age 68, 43% females; PIVUS [Prospective Investigation of the Vasculature in Uppsala Seniors], n=897, mean age 70, 51% females; and ULSAM [Uppsala Longitudinal Study of Adult Men], n=1118, mean age 71, all males), with available data on incident atrial fibrillation during 10 to 12 years of follow-up. A meta-analysis of ULSAM and PIVUS was used as a discovery sample and TwinGene was used for validation. In PIVUS, we also investigated associations between metabolites of interest and echocardiographic indices of myocardial geometry and function. Genome-wide association studies were performed in all 3 cohorts for metabolites of interest. In the meta-analysis of PIVUS and ULSAM with 430 incident cases, 4 metabolites were associated with incident atrial fibrillation at a false discovery rate <5%. Of those, only 9-decenoylcarnitine was associated with incident atrial fibrillation and replicated in the TwinGene sample (288 cases) following adjustment for traditional risk factors (hazard ratio, 1.24 per unit; 95% CI, 1.06-1.45, P=0.0061). A meta-analysis of all 3 cohorts disclosed another 4 significant metabolites. In PIVUS, 9-decenoylcarnitine was related to left atrium size and left ventricular mass. A Mendelian randomization analysis did not suggest a causal role of 9-decenoylcarnitine in atrial fibrillation. Conclusions A nontargeted metabolomics analysis disclosed 1 novel replicated biomarker for atrial fibrillation, 9-Decenoylcarnitine, but this acetylcarnitine is likely not causally related to atrial fibrillation.

Left Ventricular Diastolic Dysfunction Is Associated With the Prevalence of Paroxysmal Atrial Fibrillation Determined on the Latest Echocardiographic Criteria

Background: The relationship between left ventricular diastolic dysfunction (LVDD) and paroxysmal atrial fibrillation (PAF) remains unclear because of a lack of standard measures to evaluate LVDD. Accordingly, we examined the association between the prevalence of PAF and each LVDD grade determined according to the latest American Society of Echocardiography guidelines.

Methods and Results: In all, 2,063 patients without persistent AF who underwent echocardiography at Saitama Municipal Hospital from July 2016 to June 2017 were included in the study. Patients were divided into LVDD 6 categories: No-LVDD (n=1,107), Borderline (n=392), Grade 1 (n=204), Indeterminate (n=62), Grade 2 (n=254), and Grade 3 (n=44). PAF was documented in 111 (10.0%), 81 (20.7%), 28 (13.7%), 6 (9.7%), 52 (20.5%), and 24 (54.5%) patients in the No-LVDD, Borderline, Grade 1, Indeterminate, Grade 2, and Grade 3 categories, respectively. PAF prevalence was higher in patients with Grade 3 LVDD across the whole study population. Subgroup analyses showed that the prevalence of PAF increased with increased LVDD grade in patients with reduced left ventricular ejection fraction. This relationship was significant in multivariate analysis including various patient characteristics.

Conclusions: LVDD severity determined on the basis of the latest echocardiographic criteria was associated with the prevalence of PAF. The present findings shed light on the development of new therapeutic markers for PAF.

Characterization of cardiac mechanics and incident atrial fibrillation in participants of the Cardiovascular Health Study

BACKGROUND. Left atrial (LA) and left ventricular (LV) remodeling are associated with atrial fibrillation (AF). The prospective associations of impairment in cardiac mechanical function, as assessed by speckle-tracking echocardiography, with incident AF are less clear.

METHODS. In the Cardiovascular Health Study, a community-based cohort of older adults, participants free of AF with echocardiograms of adequate quality for speckle tracking were included. We evaluated the associations of indices of cardiac mechanics (LA reservoir strain, LV longitudinal strain, and LV early diastolic strain rate) with incident AF.

RESULTS. Of 4341 participants with strain imaging, participants with lower LA reservoir strain were older, had more cardiometabolic risk factors, and had lower renal function at baseline. Over a median follow-up of 10 years, 497 (11.4%) participants developed AF. Compared with the highest quartile of LA reservoir strain, the lowest quartile of LA reservoir strain was associated with higher risk of AF after covariate adjustment, including LA volume and LV longitudinal strain (Hazard Ratio [HR], 1.80; 95% CI, 1.31–2.45; P < 0.001). The association of LA reservoir strain and AF was stronger in subgroups with higher blood pressure, NT-proBNP, and LA volumes. There were no associations of LV longitudinal strain and LV early diastolic strain rate with incident AF after adjustment for LA reservoir strain.

CONCLUSION. Lower LA reservoir strain was associated with incident AF, independent of LV mechanics, and with stronger associations in high-risk subgroups. These findings suggest that LA mechanical dysfunction precedes the development of AF. Therapies targeting LA mechanical dysfunction may prevent progression to AF.

FUNDING. This research was supported by contracts HHSN268201200036C, HHSN268200800007C, HHSN268201800001C, N01HC55222, N01HC85079, N01HC85080, N01HC85081, N01HC85082, N01HC85083, and N01HC85086 and grants KL2TR001424, R01HL107577, U01HL080295, and U01HL130114 from the NIH’s National Center for Advancing Translational Sciences, and National Heart, Lung, and Blood Institute (NHLBI), with additional contribution from the National Institute of Neurological Disorders and Stroke (NINDS). Additional support was provided by R01AG023629 from the National Institute on Aging (NIA). A full list of principal CHS investigators and institutions can be found at CHS-NHLBI.org.

Left atrial reservoir strain was independently associated with higher risk of atrial fibrillation in this community-based cohort of elderly adults.

Left atrial strain and diastolic function abnormalities in obese and type 2 diabetic adolescents and young adults

Background

Adults with obesity and type 2 diabetes mellitus (T2DM) related to obesity are at increased risk of heart failure with preserved ejection fraction (HFpEF). Whether left ventricular (LV) diastolic function abnormalities related to obesity and T2DM start in adolescence and early adulthood is unknown. We non-invasively evaluated the differences seen in LV diastolic and left atrial (LA) function in adolescents and young adults with obesity and T2DM.

Methods

We analyzed echocardiographic measures of LV diastolic function in patients with structurally normal hearts which were divided into 3 groups (normal weight, obese, and T2DM). Spectral and tissue Doppler and 2-D speckle tracking measurements of diastolic function were obtained. Logistic regression was performed to compare the prevalence of abnormalities in diastolic function based on the worst 25th percentile for each measure to determine the prevalence of diastolic and LA function abnormalities in obese and T2DM patients.

Results

331 teenagers and young adults (median age 22.1 years) were analyzed (101 normal weight, 114 obese, 116 T2DM). Obese and T2DM group had lower E/A and higher E/e′. Obese and T2DM patients had significantly lower atrial reservoir, conduit, and booster strain and worse reservoir and conduit strain rate compared to normal patients (p < 0.001 for all measures). All patients had normal LA volumes. On multivariable analysis, conduit strain and reservoir and conduit strain rate were independently associated with having below the 25th percentile e′. Conduit strain rate was independently associated with having below the 25th percentile for mitral E/A ratio on multivariable analysis.

Conclusions

Abnormal indices of LV diastolic function are detected in adolescents and young adults with obesity and T2DM. LA function and strain analysis were able to detect evidence of decreased reservoir, conduit, and booster strain in these patients although LA volume was normal. The use of LA function strain may increase our ability to detect early diastolic function abnormalities in this population.

Tissue Doppler Imaging and strain rate of the left atrial lateral wall: age related variations and comparison with parameters of diastolic function

Background

Strain Rate Imaging (SRI) is one of the most used techniques to study left atrial (LA) and diastolic function. Its availability in low-income countries is diminished since it requires additional expensive software, among other limitations. In contrast, Tissue Doppler Imaging (TDI) is widely available and easy to use. We hypothesize TDI could detect changes in LA and diastolic function associated with age similarly to SRI. The aim of this study is to evaluate the effects of age on LA and diastolic function assessed by LA lateral wall TDI online by spectral pulse, and to compare them with age-related variations of LA SRI and other parameters of diastolic function in a population of healthy adults.

Materials and methods

Ninety-one healthy adults were prospectively evaluated. In apical four - chamber view the LA lateral wall was divided in three portions. Peak velocities of basal and mid portions were measured with TDI online by spectral pulse and with SRI by speckle tracking. A first positive wave (S’la and SRS) and two negative waves (E’la and SRE, and A’la and SRA respectively) were obtained. E’la/A’la ratio and SRE/SRA ratio were analyzed. The distribution of the variables by age subgroups was described and analyzed. Correlation analyses were performed.

Results

The median age was 42 years old and 54.9% were female. E’la/A’la showed a negative good correlation with age. E’la/A’la and SRE/SRA ratios changed from > 1 to < 1 in the age group of 41–50 years old, while this occurred in the group of 51–60 years old for the E/A ratio. Lateral and septal mitral annulus E´ showed decrease with age and prolongation of E-wave deceleration time was observed in the age group over 61 years old.

Conclusion

Normal values​​ according to age group of TDI of the LA lateral wall were obtained. Age-related changes in LA and diastolic function could be detected as early with TDI as with SRI. Future studies are required to explore if this method could be used to address in part LA or diastolic function in other populations with established cardiovascular disease or at risk of presenting it, which could be useful in low-income settings, where SRI is not available.

Cardiac Imaging After Ischemic Stroke or Transient Ischemic Attack

PURPOSE OF REVIEW

Cardiac imaging after ischemic stroke or transient ischemic attack (TIA) is used to identify potential sources of cardioembolism, to classify stroke etiology leading to changes in secondary stroke prevention, and to detect frequent comorbidities. This article summarizes the latest research on this topic and provides an approach to clinical practice to use cardiac imaging after stroke.

RECENT FINDINGS

Echocardiography remains the primary imaging method for cardiac work-up after stroke. Recent echocardiography studies further demonstrated promising results regarding the prediction of non-permanent atrial fibrillation after ischemic stroke. Cardiac magnetic resonance imaging and computed tomography have been tested for their diagnostic value, in particular in patients with cryptogenic stroke, and can be considered as second line methods, providing complementary information in selected stroke patients. Cardiac imaging after ischemic stroke or TIA reveals a potential causal condition in a subset of patients. Whether systematic application of cardiac imaging improves outcome after stroke remains to be established.

Left Atrial Function after Atrial Fibrillation Cryoablation Concomitant to Minimally Invasive Mitral Valve Repair: A Pilot Study on Long-Term Results and Clinical Implications

Background and Objectives: Surgical atrial fibrillation (AF) ablation concomitant to minimally invasive mitral valve repair has been proven to offer improved short- and long-term sinus rhythm (SR) maintenance compared to mitral valve surgery only. The objective of the present study was to explore, by thorough echocardiographic assessment, long-term morphological and functional left atrial (LA) outcomes after this combined surgical procedure. Materials and Methods: From October 2006 to November 2015, 48 patients underwent minimally invasive mitral valve repair and concomitant surgical AF cryoablation. Results: After 3.8 ± 2.2 years, 30 (71.4%) of those completing the follow-up (n = 42, 87.5%) presented SR. During follow-up, four (9.5%) patients suffered from cerebrovascular accidents and two of these subjects had a long-standing persistent AF relapse and were in AF at the time of the event, while the other two were in SR. An echocardiographic study focused on LA characteristics was performed in 29 patients (69.0%). Atrial morphology and function (e.g., maximal LA volume indexed to body surface area and total LA emptying fraction derived from volumes) in patients with stable SR (60.6 ± 13.1 mL/mq and 25.1 ± 7.3%) were significantly better than in those with AF relapses (76.8 ± 16.2 mL/mq and 17.5 ± 7.4%; respectively, p = 0.008 and p = 0.015). At follow-up, patients who suffered from ischemic cerebral events had maximal LA volume indexed to body surface area 61 ± 17.8 mL/mq, with total LA emptying fraction derived from volumes 23.6 ± 13.7%; patients with strokes in SR showed very enlarged LA volume (>70 mL/mq). Conclusions: AF cryoablation concomitant with minimally invasive mitral valve repair provides a high rate of SR maintenance and this relates to improved long-term morphological and functional LA outcomes. Further prospective studies are needed to define the cut-off values determining an increase in the risk for thromboembolic complications in patients with restored stable SR.

Transmitral inflow wave and progression from paroxysmal to permanent atrial fibrillation in Asian people

Objective

Paroxysmal atrial fibrillation could progress to permanent atrial fibrillation. Whether the transmitral inflow waves could be used to predict progression from paroxysmal atrial fibrillation to permanent atrial fibrillation is unknown. Therefore, we investigated the association between the transmitral inflow waves and progression of paroxysmal atrial fibrillation.

Method

We performed a retrospective study by analysing clinical and echocardiographic data from 88 patients with paroxysmal atrial fibrillation. We excluded patients who had structural heart disease, significant valvular disease, cardiomyopathy, cardiac device implantation or a left ventricular ejection fraction <50%.

Result

The patients with progression to permanent atrial fibrillation were more likely to be male and had lower peak A velocity than those without progression. After adjusting for covariates, lower peak A velocity remained the independent predictor of progression to permanent atrial fibrillation (p=0.025).

Conclusion

The A velocity could be useful for predicting progression to permanent atrial fibrillation in Asian people.

Tissue Doppler imaging of the atrial lateral wall: Correlation with atrial strain rate and parameters of diastolic function

OBJECTIVE

To evaluate the velocity profile of the lateral wall of the left atrium (LA) using pulsed-wave color tissue Doppler imaging (TDI) on line and its correlation with two-dimensional strain rate imaging (SRI) by speckle tracking, of equal segments and phases, and other parameters of diastolic function in a population of individuals without known cardiovascular disease.

MATERIALS AND METHODS

A total of 91 adults aged 18-74 years, without cardiovascular history, hypertension, diabetes, dyslipidemia or obesity, were evaluated. A Doppler echocardiogram was performed. The lateral wall of the LA was divided subjectively into three portions, the atrial roof was excluded; the peak velocities of the basal and midportions, and their average, were measured with pulsed-wave TDI on line and SRI. Using both techniques, a first positive wave (S'la and SRS-reservoir phase) and two negative waves (E'la and SRE-conduit phase-and A'la and SRA-atrial systole-respectively) were obtained. E'la/A'la ratio and SRE/SRA ratio were analyzed.

RESULTS

The median age was 42 years, and 54.9% of the subjects were female. S'la presented moderate correlation with S' lateral mitral annulus. Both E'la and the E'la/A'la relationships showed moderate to good correlation with various diastolic dysfunction parameters evaluated and SRI. A'la did not present a statistically significant correlation with any of the variables evaluated.

CONCLUSION

Evaluation of the lateral wall of the LA by pulsed-wave color TDI on line is feasible in the vast majority of patients. In the conduit phase, E'la and the E'la/A'la relationship showed correlation with the parameters that evaluate diastolic function and SRI.

Arterial hypertension and atrial fibrillation: standard and advanced echocardiography from diagnosis to prognostication

: Structural changes in left and right cardiac chambers that occur in arterial hypertension (AH) may lead to an increased risk of atrial fibrillation. Considering that AH is currently the most common cardiovascular disease in the general population, it represents a major risk factor for atrial fibrillation development. This review explores the complex relationship between atrial fibrillation and AH, starting from its pathophysiological basis. It focuses on the role of echocardiography in the management of hypertensive and atrial fibrillation patients, with emphasis on what should be evaluated about left ventricular remodeling, diastolic and systolic function, left atrial (LA) size and function and right ventricular deformation in patients with AH.

Left Ventricular Diastolic Dysfunction in the Community: Impact of Diagnostic Criteria on the Burden, Correlates, and Prognosis

BACKGROUND

Left ventricular diastolic dysfunction (DD) is common, particularly in women and older individuals, and it is associated with adverse cardiovascular outcomes. We evaluated the impact of age- and sex-specific diagnostic criteria on the assessment of DD in the community-based Framingham Heart Study.

METHODS AND RESULTS

We estimated age- and sex-specific reference limits for echocardiographic measures of DD in a healthy reference subsample (N=2355, mean age 44 years, 66% women). The prevalence, correlates, and association with future cardiovascular disease were compared for DD using age- and sex-specific versus single cut point reference limits in a broad sample (N=6102, mean age 50 years, 56% women). Using age- and sex-specific criteria, DD was present in ≈25% to 30% of individuals across age groups, and it was directly associated with a number of modifiable risk factors. In contrast, with single cut point criteria, age was the primary determinant of DD. During follow-up (mean 7.9±2.2 years), incident cardiovascular disease occurred in 213 of 5770 individuals. Using age- and sex-specific criteria, mild and moderate-severe DD were associated with 50% (95% confidence interval, 1.09-2.05) and 65% (95% confidence interval, 1.14-2.38) higher incidences of cardiovascular disease, respectively, in age- and sex-adjusted analyses. With single cut point criteria, moderate-severe DD (hazard ratio, 1.66; 95% confidence interval, 1.05-2.61), but not mild DD (hazard ratio, 0.94; 95% confidence interval, 0.63-1.40), was associated with incident cardiovascular disease.

CONCLUSIONS

Age- and sex-specific reference limits may result in DD assessments that are less dependent on age, more robustly related to modifiable risk factors, and are more closely associated with incident cardiovascular disease.

Dissecting Clinical and Metabolomics Associations of Left Atrial Phasic Function by Cardiac Magnetic Resonance Feature Tracking

Among community cohorts, associations between clinical and metabolite factors and complex left atrial (LA) phasic function assessed by cardiac magnetic resonance (CMR) feature tracking (FT) are unknown. Longitudinal LA strain comprising reservoir strain (εs), conduit strain (εe) and booster strain (εa) and their corresponding peak strain rates (SRs, SRe, SRa) were measured using CMR FT. Targeted mass spectrometry measured 83 circulating metabolites in serum. Sparse Principal Component Analysis was used for data reduction. Among community adults (n = 128, 41% female) (mean age: 70.5 ± 11.6 years), age was significantly associated with εs (β = -0.30, p < 0.0001), εe (β = -0.3, p < 0.0001), SRs (β = -0.02, p < 0.0001), SRe (β = 0.04, p < 0.0001) and SRe/SRa (β = -0.01, p = 0.012). In contrast, heart rate was significantly associated with εa (β = 0.1, p = 0.001) and SRa (β = -0.02, p < 0.0001). Serine was significantly associated with εs (β = 10.1, p = 0.015), SRs (β = 0.5, p = 0.033) and SRa (β = -0.9, p = 0.016). Citrulline was associated with εs (β = -4.0, p = 0.016), εa (β = -3.4, p = 0.002) and SRa (β = 0.4, p = 0.019). Valine was associated with ratio of SRe:SRa (β = -0.4, p = 0.039). Medium and long chain dicarboxyl carnitines were associated with εs (β = -0.6, p = 0.038). Phases of LA function were differentially associated with clinical and metabolite factors. Metabolite signals may be used to advance mechanistic understanding of LA disease in future studies.

Comorbidities and Cardiometabolic Disease: Relationship With Longitudinal Changes in Diastolic Function

OBJECTIVES

This study sought to evaluate the course, correlates, and prognosis of longitudinal changes in left ventricular (LV) diastolic dysfunction (DD) in the community-based Framingham Heart Study.

BACKGROUND

Relationships of clinical risk factors to longitudinal progression of DD are incompletely understood.

METHODS

Diastolic function was assessed by echocardiography performed at consecutive examinations (visits 1 and 2, mean interval 5.6 years) in 1,740 participants (64 ± 8 years of age at visit 1, 59% women) with normal LV systolic function and no atrial fibrillation.

RESULTS

Of 1,615 individuals with normal-to-mild DD at visit 1, 198 (12%) progressed to ≥ moderate DD at visit 2. Progression was more likely in women and with advancing age (p < 0.0001). Of 125 individuals with ≥ moderate DD at visit 1, 25 (20%) regressed to normal-to-mild DD by visit 2. Regression of DD was associated with younger age (p < 0.03). In stepwise regression models, age, female sex, baseline and changes in systolic blood pressure, diastolic blood pressure, body mass index, serum triglycerides, and diabetes were positively associated with worsening diastolic function (all p < 0.05). Noncardiac comorbidity tracked with progressive DD. Cardiovascular disease (CVD) or death events occurred in 44 of 1,509 participants free of CVD at visit 2, during 2.7 ± 0.6 years of post-visit 2 follow-up. Presence of ≥ moderate DD was associated with higher risk (age- and sex-adjusted hazard ratio for CVD or death: 2.14; 95% confidence interval: 1.06 to 4.32; p = 0.03).

CONCLUSIONS

In a community-based cohort of middle-aged to older adults, cardiometabolic risk factors and noncardiac comorbidities were associated with DD progression. Moderate or worse DD was associated with higher risk of CVD or death.

Association of Left Atrial Function Index with Atrial Fibrillation and Cardiovascular Disease: The Framingham Offspring Study

BACKGROUND

Left atrial (LA) size, a marker of atrial structural remodeling, is associated with increased risk for atrial fibrillation (AF) and cardiovascular disease (CVD). LA function may also relate to AF and CVD, irrespective of LA structure. We tested the hypothesis that LA function index (LAFI), an echocardiographic index of LA structure and function, may better characterize adverse LA remodeling and predict incident AF and CVD than existing measures.

METHODS AND RESULTS

In 1786 Framingham Offspring Study eighth examination participants (mean age, 66±9 years; 53% women), we related LA diameter and LAFI (derived from the LA emptying fraction, left ventricular outflow tract velocity time integral, and indexed maximal LA volume) to incidence of AF and CVD on follow-up. Over a median follow-up of 8.3 years (range, 7.5-9.1 years), 145 participants developed AF and 139 developed CVD. Mean LAFI was 34.5±12.7. In adjusted Cox regression models, lower LAFI was associated with higher risk of incident AF (hazard ratio=3.83, 95% confidence interval=2.23-6.59, lowest [Q1] compared with highest [Q4] LAFI quartile) and over 2-fold higher risk of incident CVD (hazard ratio=2.20, 95% confidence interval=1.32-3.68, Q1 versus Q4). Addition of LAFI, indexed maximum LA volume, or LA diameter to prediction models for AF or CVD did not significantly improve model discrimination for either outcome.

CONCLUSIONS

In our prospective investigation of a moderate-sized community-based sample, LAFI, a composite measure of LA size and function, was associated with incident AF and CVD. Addition of LAFI to the risk prediction models for AF or CVD, however, did not significantly improve their performance.

Left atrium: the last bulwark before overt heart failure

Heart failure (HF) with preserved ejection fraction (HFpEF) has emerged as an important public health issue in recent years. It represents the most common type of HF in ambulatory setting, and it has been recognized as a different entity from the reduced ejection fraction (EF) form. In HFpEF, continuous growing attention has been focused on the role of the left atrium (LA) in preserving good ventricular function and asymptomatic condition of the patient since the very first stages of diastolic dysfunction (DD). Non-invasive and complete echocardiographic evaluation of diastolic phase cannot exempt from accurately analyzed LA size, mostly LA volume, and its function, in particular LA myocardial deformation by speckle tracking echocardiography (STE). This review examines the expanding role of the LA in DD and HFpEF and the importance of its complete assessment in various settings, from diagnosis to correlation with major cardiovascular events.

Diastolic Electrocardiographic Parameters Predict Implantable Device Detected Asymptomatic Atrial Fibrillation

Background:

Atrial fibrillation is the most common clinically significant arrhythmia. It is now established that atrial high-rate episodes are highly correlated with atrial fibrillation.

Aims:

To investigate the relation between diastolic electrocardiographic parameters and subclinical atrial fibrillation detected by cardiac implantable electronic devices.

Study Design:

Ccross-sectional study.

Methods:

A total of 203 patients who had a dual-chamber, rate-modulated pacing pacemaker implanted due to sinus node dysfunction were prospectively enrolled in this study. Atrial high-rate episodes were defined as any lasting more than 5 min with an atrial rate of ≥220 beats per minute during the previous year. Patient groups were categorized on the basis of pacemaker interrogation as the absence of atrial high-rate episodes [atrial high-rate episodes (-)] and the presence of atrial high-rate episodes [atrial high-rate episodes (+)]. Episodes related to atrial over sensing were excluded. Twelve-lead surface electrocardiography was independently analyzed by two experienced readers for the measurement of diastolic electrocardiography parameters.

Results:

Among 203 patients (mean age: 67.5±9.1, 60.1% male), 51 (25.1%) with atrial high-rate episodes were defined as group 1 and 152 (74.9%) without atrial high-rate episodes were defined as group 2. Both groups were similar in terms of demographic characteristics and cardiovascular risk factors. Tend-Q and Tend-P were significantly longer in group 2. PQ interval was statistically longer in group 1. Corrected QT interval was significantly longer in group 1. Diastolic electrocardiography index, heart rate and PQ and QT intervals were the only independent predictors of atrial high-rate episodes in patients with dual pacemakers in multivariate analysis.

Conclusion:

Abnormal diastolic electrocardiography parameters are powerful predisposing factors for the initiation of incident atrial fibrillation. Diastolic electrocardiography parameters and a novel diastolic index predict atrial high-rate episodes. Evaluating these parameters enables clinicians to identify patients who are at high risk and who may benefit from prophylactic treatment.

Clinical and Echocardiographic Correlates of Left Atrial Function Index: The Framingham Offspring Study

BACKGROUND

Left atrial (LA) remodeling is a predictor of cardiovascular disease (CVD). We performed measurement of the LA function index (LAFI), a composite measure of LA structure and function, in a community-based cohort and here report the distribution and cross-sectional correlates of LAFI.

METHODS

In 1,719 Framingham Offspring Study participants (54% women, mean age 66 ± 9 years), we derived LAFI from the LA emptying fraction, left ventricular (LV) outflow tract velocity time integral, and indexed maximal LA volume. We used multivariable linear regression to assess the clinical and echocardiographic correlates of LAFI adjusting for age, sex, anthropometric measurements, and CVD risk factors.

RESULTS

The average LAFI was 35.2 ± 12.1. Overall, LAFI declined with advancing age (β = -0.27, P < .001). LAFI was significantly higher (37.5 ± 11.6) in a subgroup of participants free of CVD and CVD risk factors compared with those with either of these conditions (34.5 ± 12.2). In multivariable models, LAFI was inversely related to antihypertensive use (β = -1.26, P = .038), prevalent atrial fibrillation (β = -4.46, P = .001), heart failure (β = -5.86, P = .008), and coronary artery disease (β = -2.01, P = .046). In models adjusting for echocardiographic variables, LAFI was directly related to LV ejection fraction (β = 14.84, P < .001) and inversely related to LV volume (β = -7.03, P < .001).

CONCLUSIONS

LAFI was inversely associated with antihypertensive use and prevalent CVD and was related to established echocardiographic traits of LV remodeling. Our results offer normative ranges for LAFI in a white community-based sample and suggest that LAFI represents a marker of pathological atrial remodeling.

Cardiac Magnetic Resonance-Measured Left Atrial Volume and Function and Incident Atrial Fibrillation: Results From MESA (Multi-Ethnic Study of Atherosclerosis)

BACKGROUND

Early detection of structural changes in left atrium (LA) before atrial fibrillation (AF) development could be helpful in identification of those at higher risk for AF. Using cardiac magnetic resonance imaging, we examined the association of LA volume and function, and incident AF in a multiethnic population free of clinical cardiovascular diseases.

METHODS AND RESULTS

In a case-cohort study embedded in MESA (Multi-Ethnic Study of Atherosclerosis), baseline LA size and function assessed by cardiac magnetic resonance feature-tracking were compared between 197 participants with incident AF and 322 participants randomly selected from the whole MESA cohort. Participants were followed up for 8 years. Incident AF cases had a larger LA volume and decreased passive, active, and total LA emptying fractions and peak global LA longitudinal strain (peak LA strain) at baseline. In multivariable analysis, elevated LA maximum volume index (hazard ratio, 1.38 per SD; 95% confidence interval, 1.01-1.89) and decreased peak LA strain (hazard ratio, 0.68 per SD; 95% confidence interval, 0.48-0.96), and passive and total LA emptying fractions (hazard ratio for passive LA emptying fractions, 0.55 per SD; 95% confidence interval, 0.40-0.75 and hazard ratio for active LA emptying fractions, 0.70 per SD; 95% confidence interval, 0.52-0.95), but not active LA emptying fraction, were associated with incident AF.

CONCLUSIONS

Elevated LA volumes and decreased passive and total LA emptying fractions were independently associated with incident AF in an asymptomatic multiethnic population. Including LA functional variables along with other risk factors of AF may help to better risk stratify individuals at risk of AF development.

Peak Early Diastolic Transmitral Velocity As A Surrogate Marker Of Short-Term Atrial Fibrillation Recurrence After Electrical Cardioversion

OBJECTIVES

The aim of this study was to assess if peak early diastolic transmitral velocity (E-wave) can be used as a surrogate marker of short-term atrial fibrillation (AF) recurrence.

METHODS

We prospectively studied 57 consecutive patients who underwent electrical cardioversion (ECV) for AF and successfully converted to sinus rhythm. N-terminal brain natriuretic peptide levels (BNP) before and after ECV was measured in all patients. The follow-up included physical examination and a 12-lead electrocardiogram 14 days and one month after the ECV.

RESULTS

In 42.1% patients AF recurred during one-month follow-up period. Gender, presence of mitral regurgitation, treatment with angiotensin II receptor blocker and left atrium diameter independently influenced E-wave velocity before ECV. E-wave velocity fell immediately after successful ECV (94.0±27 cm/s vs 79.7±23 cm/s, P<0.0001). E-wave velocity before ECV>94 cm/s and E-wave velocity after ECV >80 cm/s were predictors of one-month AF recurrence [(Hazard Ratio) HR=3.62 with 95% CI=1.49-8.78 and HR=3.76 with 95% CI=1.40-10.10, respectively]. E-wave velocity before and E-wave velocity after ECV remained predictors of AF recurrence but only in non-hypertensive patients (HR=1.01 with 95% C.I=1.01-1.03 and HR=1.03 with 95% C.I=1.01-1.06, respectively). Similarly, BNP levels before and after ECV were associated with an increased the risk of AF recurrence (HR=1.14 with 95% C.I 1.01-1.28 and HR= 1.16 with 95% C.I 1.03- 1.31, respectively). The addition of BNP levels to E-wave velocity before ECV appeared to have incremental value on short-term AF recurrence but at a marginally statistical significance (LR chi2=3.28, p=0.07).

CONCLUSIONS

E-wave velocity before and after ECV appears to be a marker of short-term recurrence of AF.

Traditional Cardiovascular Risk Factors for Incident Atrial Fibrillation

To prevent atrial fibrillation (AF), it is essential to reduce its risk factors and extend healthy life expectancy as a result. There are few reviews on the AF risk factors. We discuss them and approach the prevention of AF. We briefly review traditional risk factors for incident AF, especially focusing on high blood pressure, overweight/obesity, dyslipidemia, diabetes, tobacco smoking, and excessive drinking. When trying to prevent AF by modifying lifestyle, it is important to comprehensively utilize the risk factors for AF to predict the 10-year as an AF risk score. However, there are only 2 risk scores of AF just for the US population. There are few studies of the AF risk factors in non-Western populations. A risk score for incident AF in non-Westerners is awaited because different race and lifestyles may have different contributions as AF risk factors. An AF risk score in accordance with race could be useful for identifying persons with a high risk of AF in order to encourage them to consult a doctor and encourage lifestyle modifications before the onset of AF. (Circ J 2016; 80: 2415-2422).

Methodological Gaps in Left Atrial Function Assessment by 2D Speckle Tracking Echocardiography

The assessment of left atrial (LA) function is used in various cardiovascular diseases. LA plays a complementary role in cardiac performance by modulating left ventricular (LV) function. Transthoracic two-dimensional (2D) phasic volumes and Doppler echocardiography can measure LA function non-invasively. However, evaluation of LA deformation derived from 2D speckle tracking echocardiography (STE) is a new feasible and promising approach for assessment of LA mechanics. These parameters are able to detect subclinical LA dysfunction in different pathological condition. Normal ranges for LA deformation and cut-off values to diagnose LA dysfunction with different diseases have been reported, but data are still conflicting, probably because of some methodological and technical issues. This review highlights the importance of an unique standardized technique to assess the LA phasic functions by STE, and discusses recent studies on the most important clinical applications of this technique.

Prognostic Relevance of Left Atrial Dysfunction in Heart Failure With Preserved Ejection Fraction

BACKGROUND

Left atrial (LA) size is an established marker of risk for adverse outcomes in heart failure with preserved ejection fraction (HFpEF). However, the independent prognostic importance of LA function in HFpEF is not known.

METHODS AND RESULTS

We assessed LA function measured by speckle-tracking echocardiography in 357 patients with HFpEF enrolled in the Treatment Of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist (TOPCAT) trial who were in sinus rhythm at the time of echocardiography. Lower peak LA strain, indicating LA dysfunction, was associated with older age, higher prevalence of atrial fibrillation and left ventricular (LV) hypertrophy, worse LV and right ventricular systolic function, and worse LV diastolic function. At a mean follow-up of 31 months (interquartile range, 18-43months), 91 patients (25.5%) experienced the primary composite end point of cardiovascular death, HF hospitalization, and aborted sudden death. Lower peak LA strain was associated with a higher risk of the composite end point (hazard ratio, 0.96 per unit of reduction in strain; 95% confidence interval, 0.94-0.99; P=0.009) and of HF hospitalization alone (hazard ratio, 0.95 per unit of reduction in strain; 95% confidence interval, 0.92-0.98; P=0.003). The association of LA strain with incident HF hospitalization remained significant after adjustment for clinical confounders, but not after further adjustment for LV global longitudinal strain and the E/E' ratio, parameters of LV systolic and diastolic function, respectively.

CONCLUSIONS

LA dysfunction in HFpEF is associated with a higher risk of HF hospitalization independent of potential clinical confounders, but not independent of LV strain and filling pressure. Impairment in LV systolic and diastolic function largely explains the association between impaired LA function and higher risk of HF hospitalization in HFpEF.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00094302.

MicroRNAs as Biomarkers for Acute Atrial Remodeling in Marathon Runners (The miRathon Study--A Sub-Study of the Munich Marathon Study)

Introduction

Physical activity is beneficial for individual health, but endurance sport is associated with the development of arrhythmias like atrial fibrillation. The underlying mechanisms leading to this increased risk are still not fully understood. MicroRNAs are important mediators of proarrhythmogenic remodeling and have potential value as biomarkers in cardiovascular diseases. Therefore, the objective of our study was to determine the value of circulating microRNAs as potential biomarkers for atrial remodeling in marathon runners (miRathon study).

Methods

30 marathon runners were recruited into our study and were divided into two age-matched groups depending on the training status: elite (ER, ≥55 km/week, n = 15) and non-elite runners (NER, ≤40 km/week, n = 15). All runners participated in a 10 week training program before the marathon. MiRNA plasma levels were measured at 4 time points: at baseline (V1), after a 10 week training period (V2), immediately after the marathon (V3) and 24h later (V4). Additionally, we obtained clinical data including serum chemistry and echocardiography at each time point.

Results

MiRNA plasma levels were similar in both groups over time with more pronounced changes in ER. After the marathon miR-30a plasma levels increased significantly in both groups. MiR-1 and miR-133a plasma levels also increased but showed significant changes in ER only. 24h after the marathon plasma levels returned to baseline. MiR-26a decreased significantly after the marathon in elite runners only and miR-29b showed a non-significant decrease over time in both groups. In ER miRNA plasma levels showed a significant correlation with LA diameter, in NER miRNA plasma levels did not correlate with echocardiographic parameters.

Conclusion

MiRNAs were differentially expressed in the plasma of marathon runners with more pronounced changes in ER. Plasma levels in ER correlate with left atrial diameter suggesting that circulating miRNAs could potentially serve as biomarkers of atrial remodeling in athletes.

Association between diastolic dysfunction and future atrial fibrillation in the Tromsø Study from 1994 to 2010

Objective

To investigate the association between echocardiographic measurements with emphasis on diastolic dysfunction and risk of atrial fibrillation (AF) in a population-based cohort study.

Methods

We followed 2406 participants from the Tromsø Study from 1994 to 2010. Left atrial (LA) size and mitral Doppler indices as measured by echocardiography were used for evaluating diastolic dysfunction. Information concerning age, systolic blood pressure, height, heart rate, body mass index, total and high-density lipoprotein cholesterol, self-reported use of alcohol, smoking, coffee, physical activity, antihypertensive treatment, prevalent coronary heart disease, valvular heart disease, heart failure, hypertrophy, diabetes and palpitations were obtained at baseline. The outcome measure was clinical AF, documented by an ECG.

Results

AF was detected in 462 subjects (193 women). Mean age at baseline was 62.6 years. Incidence rate of clinical AF was 12.6 per 1000 person-years. In multivariable Cox proportional hazards regression analysis, moderately enlarged LA was associated with 60% (95% CI 1.2 to 2.0) increased risk of AF. Severely enlarged LA had HR for AF of 4.2 (95% CI 2.7 to 6.5) with p value for linear trend <0.001, and the association was similar in both sexes. Abnormal mitral Doppler flow adjusted for predictor variables did not show a statistically significant association with AF risk. However, when LA size was also adjusted for, the risk of AF increased by 30% (95% CI 1.0 to 1.6).

Conclusions

Our findings suggest that enlarged LA as a measure for diastolic dysfunction is a significant risk factor for AF in both sexes, and adding measures of abnormal diastolic flow increased the predictive ability significantly.