Measures of left atrial function predict incident heart failure in a low-risk general population: the Copenhagen City Heart Study

Left atrial cardiomyopathy: Pathophysiological insights, assessment methods and clinical implications

Atrial cardiomyopathy is defined as any complex of structural, architectural, contractile or electrophysiological changes affecting atria, with the potential to produce clinically relevant manifestations. Most of our knowledge about the mechanistic aspects of atrial cardiomyopathy is derived from studies investigating animal models of atrial fibrillation and atrial tissue samples obtained from individuals who have a history of atrial fibrillation. Several noninvasive tools have been reported to characterize atrial cardiomyopathy in patients, which may be relevant for predicting the risk of incident atrial fibrillation and its related outcomes, such as stroke. Here, we provide an overview of the pathophysiological mechanisms involved in atrial cardiomyopathy, and discuss the complex interplay of these mechanisms, including aging, left atrial pressure overload, metabolic disorders and genetic factors. We discuss clinical tools currently available to characterize atrial cardiomyopathy, including electrocardiograms, cardiac imaging and serum biomarkers. Finally, we discuss the clinical impact of atrial cardiomyopathy, and its potential role for predicting atrial fibrillation, stroke, heart failure and dementia. Overall, this review aims to highlight the critical need for a clinically relevant definition of atrial cardiomyopathy to improve treatment strategies.

Association between insulin resistance and cardiac remodeling in HER2-positive breast cancer patients: a real-world study

BACKGROUND

Insulin resistance is an overlapping risk factor for both heart and breast cancer, while its interaction with cardiotoxicity in breast cancer (BC) patients is not clear. This study investigated the impact of insulin resistance on cardiac remodeling in patients with human epidermal growth factor receptor 2 (HER2)-positive BC during and after trastuzumab therapy in real-world clinical practice.

METHODS

HER2-positive BC patients who received trastuzumab treatment between December 2012 and December 2017 were reviewed and 441 patients with baseline metabolic indices and serial echocardiographic measurements (baseline, 6, 12, and 18 months) after trastuzumab therapy initiation were included. Repeated measurement analysis of variance was used to evaluate temporal trends in multiparameter echocardiography. Linear mixed model was applied to further evaluate the role of insulin resistance in forementioned changes. Correlation of homeostasis model assessment-estimated insulin resistance (HOMA-IR) and triglyceride-glucose index (TyG) levels to changes in echocardiography parameters was explored.

RESULTS

Of 441 patients (mean age 54 ± 10 [SD] years), 61.8% received anthracycline-based chemotherapy, 33.5% received left-sided radiotherapy, 46% received endocrine therapy. No symptomatic cardiac dysfunction was observed over the therapy course. A total of 19 (4.3%) participants experienced asymptomatic cancer therapy-related cardiac dysfunction (CTRCD), and the peak onset time was 12 months after the initiation of trastuzumab. Albeit relatively low CTRCD incidence, cardiac geometry remodeling, especially left atrial (LA) dilation over therapy was notable and was more severe in high HOMA-IR and TyG level groups (P < 0.01). Noteworthy, a partial reversibility of cardiac remodeling was observed with treatment cessation. Additionally, HOMA-IR level positively correlated to changes in LA diameter from baseline to 12 months (r = 0.178, P = 0.003). No significant association (all P > 0.10) was detected between HOMA-IR or TyG level and dynamic left ventricular parameter evaluation. Multivariate linear regression analysis demonstrated that higher HOMA-IR level was an independent determinant for LA enlargement in BC patients during anti-HER2 targeted therapy course after adjusting for confounding risk factors (P = 0.006).

CONCLUSION

Insulin resistance was associated with left atrial adverse remodeling (LAAR) in HER2-positive BC patients that received standard trastuzumab therapy, indicating that insulin resistance could be a supplementation to baseline cardiovascular risk stratification proforma for HER2-targeted antitumor therapies.

Diabetic microvascular complications are associated with left atrial structural alterations in asymptomatic type 2 diabetes patients: A cross-sectional study

AIMS

We used 4D-Auto LAQ to quantitatively evaluate the morphological and functional changes of left atrium in patients with asymptomatic type 2 diabetes mellitus (T2DM), and explored its correlations with diabetic microvascular complications (MICRO).

METHODS

This study included 319 patients with asymptomatic T2DM. According to the occurrence of MICRO, these patients were divided into 3 groups: patients with no complication, 1 complication, and 2-3 complications. 4D-Auto LAQ was used to evaluate left atrial volume (LAVImin, LAVImax, LAVIpre) and calculate the left atrial function (DEI, PEI, AEI) in different phases. Multiple linear regression was used to analyze the correlation between changes in left atrial volume and function and the number of MICROs in DM patients.

RESULTS

A total of 279 patients with asymptomatic T2DM were included in this study. (1) The ultrasound data of the three T2DM groups showed that there was no significant difference in left ventricular size and function among the three groups; (2) with the increase of MICRO number, the left atrial volume (LAVImin, LAVImax, LAVIpre) progressively increased, the left atrial storage function index (DEI) gradually decreased, and the differences were significant (P < 0.05). (3) Multiple linear regression analysis showed that: with the increase of MICRO number (no complication→1 complication→2-3 complications), the left atrial volume (LAVImin, LAVIpre) showed an increasing trend (both P < 0.05).

CONCLUSION

In asymptomatic T2DM patients, MICRO number showed a significant positive correlation with LAVImin and LAVIpre (P < 0.05). Therefore, the increase in left atrial volume can dynamically reflect the severity of microvascular lesions in patients with asymptomatic T2DM.

The Conundrum of HFpEF Definition: Non-Invasive Assessment Uncertainties and Alternative Diagnostic Strategies

Heart failure (HF) with preserved ejection fraction (HFpEF) is a heterogeneous syndrome including several morphological phenotypes and varying pathophysiological mechanisms. The conventional classification of HF based on left ventricular ejection fraction (LVEF) has created an oversimplification in diagnostic criteria. Although LVEF is a standardized parameter easy to calculate and broadly applied in the large clinical trials, but it is erroneously considered an index of left ventricular (LV) systolic function. Indeed,  it is affected by preload and afterload and it has limitations related to reproducibility, reduced sensitivity and scarce prognostic values especially when above 50%. Notably, additional diagnostic parameters have been recently proposed in order to improve diagnostic accuracy and to homogenise the different HFpEF populations. Unfortunately, these algorithms comprise sophisticated measurements that are difficult to apply in the daily clinical practice. Additionally, the scarce diffusion of these diagnostic criteria may have led to neutral or negative results in interventional phase 3 trials . We propose changes to the current HFpEF diagnostic approach mainly based on LVEF stratification measurement aiming towards a more inclusive model taking into consideration an integrative approach starting from the main diseases responsible for cardiac dysfunction  through to cardiac structural and functional alterations. Accordingly, with recent universal HF definitions, a stepwise model could be helpful in recognizing patients with early vs. overt HFpEF by the appraisal of specific Doppler echocardiographic variables. Thus, we would encourage the application of new criteria in order to better identify the different phenotypes and to move towards more personalized medicine.

Phenotyping the hypertensive heart

Arterial hypertension remains the most frequent cardiovascular (CV) risk factor, and is responsible for a huge global burden of disease. Echocardiography is the first-line imaging method for the evaluation of cardiac damage in hypertensive patients and novel techniques, such as 2D and D speckle tracking and myocardial work, provide insight in subclinical left ventricular (LV) impairment that would not be possible to detect with conventional echocardiography. The structural, functional, and mechanical cardiac remodelling that are detected with imaging are intermediate stages in the genesis of CV events, and initiation or intensification of antihypertensive therapy in response to these findings may prevent or delay progressive remodelling and CV events. However, LV remodelling—especially LV hypertrophy—is not specific to hypertensive heart disease (HHD) and there are circumstances when other causes of hypertrophy such as athlete heart, aortic stenosis, or different cardiomyopathies need exclusion. Tissue characterization obtained by LV strain, cardiac magnetic resonance, or computed tomography might significantly help in the distinction of different LV phenotypes, as well as being sensitive to subclinical disease. Selective use of multimodality imaging may therefore improve the detection of HHD and guide treatment to avoid disease progression. The current review summarizes the advanced imaging tests that provide morphological and functional data about the hypertensive cardiac injury.