Left atrial deformation analysis by speckle tracking echocardiography to predict exercise capacity after myocardial infarction

Parameters of the mitral apparatus in patients with ischemic and nonischemic dilated cardiomyopathy

The mitral valve apparatus is a complex structure consisting of several coordinating components: the annulus, two leaflets, the chordae tendineae, and the papillary muscles. Due to the intricate interplay between the mitral valve and the left ventricle, a disease of the latter may influence the normal function of the former. As a consequence, valve insufficiency may arise despite the absence of organic valve disease. This is designated as functional or secondary mitral regurgitation, and it arises from a series of distortions to the valve components. This narrative review describes the normal anatomy and the pathophysiology behind the mitral valve changes in ischemic and non-ischemic dilated cardiomyopathies. It also explains the value of a complete multiparametric assessment of this structure. Not only must an assessment include quantitative measures of regurgitation, but also various anatomical parameters from the mitral apparatus and left ventricle, since they carry prognostic value and are predictors of mitral valve repair success and durability.

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.

Left Atrial Strain as a Predictor of Left Ventricular Diastolic Dysfunction in Patients with Arterial Hypertension

Background and Objectives: There is emerging evidence of the usefulness of left atrial strain (LAS) in the assessment of diastolic dysfunction (DD). In this study we assess the sensitivity and specificity of LAS, to determine cut-off values and their association to DD with increased left atrial pressure (LAP) in patients with well-treated arterial hypertension. Materials and Methods: We performed a cross-sectional study on 180 subjects with well-treated arterial hypertension. All patients underwent transthoracic echocardiography. Patients were divided into two groups: a group without increased LAP and/or DD and a group with increased LAP DD. Results: In multivariate logistic regression, LAS proved to be the strongest statistically significant predictor of DD with increased LAP (OR 0.834, p < 0.0005), with AUC 0.885 and a set cut-off value of 24.27% with high sensitivity of 78.9% and specificity of 84.6%. The set cut-off for LAS > 24.27% was significantly highly prevalent in the group of DD with increased LAP 78.9% when compared to the group without increased LAP 15.4%, p < 0.0001. Conclusion: The findings of this study suggest that LAS could be a useful and highly sensitive and specific marker in the evaluation of DD. There is the potential for using LAS in everyday practice as a standard parameter in diastolic function assessment.

Relation of left atrial function with exercise capacity and muscle endurance in patients with heart failure

Aims

Both left atrial strain (LAS) and skeletal muscle endurance demonstrate a linear relationship to peak VO₂. Less is known about the relationship between central (cardiac) and peripheral (muscle endurance) limitations of exercise capacity in patients with heart failure (HF). We investigated this relationship using novel cardiac markers such as LAS and left atrial emptying fraction (LAEF).

Methods and results

We analysed echocardiographic measurements, cardiopulmonary exercise testing (CPET), and isokinetic muscle function in 55 subjects with HF and controls [17 heart failure with preserved ejection fraction (HFpEF), 18 heart failure with reduced ejection fraction (HFrEF), and 20 healthy controls]. Patients with reduced LAEF showed reduced peak VO₂: 14.3 ± 3.5 vs. 18.5 ± 3.5 mL/min/kg, P = 0.003, and reduced muscle endurance (RME): 64.3 ± 23.9 vs. 88.5 ± 32.3 Nm/kg, P = 0.028. Patients with reduced LAS showed similar results. Neither left ventricular global longitudinal strain (LVGLS) nor left atrial volume index (LAVI) was associated with RME. The area under the curve of LAS and LAEF in patients with HF in association with RME were (0.76 vs. 0.80) with 95% confidence interval (CI) (0.59–0.96, P = 0.012 vs. 0.63–0.98, P = 0.006, respectively). In a multiple linear regression, LAEF and working load measured during CPET (watt) were independent factors for RME after adjusting for age, LVGLS, and 6 min walk test (6MWT) [LAEF (B: 0.09, 95% CI: 1.01; 1.18, P = 0.024), working load (B: 0.05, 95% CI: 1.01; 1.08, P = 0.006)]. Peak torque of the left leg was associated with E/LAS (E: early diastolic) in patients with HFpEF (r = −0.6, P = 0.020). Endurance of the left leg was associated with LAEF (r = 0.79, P = 0.001) in patients with HFrEF.

Conclusions

LAS/LAEF are potential cardiac markers in demonstrating the link between cardiac and peripheral limitations of exercise capacity. Thus, integrating LAS/LAEF in the evaluation of exercise intolerance in patients with HF could be useful.

Interaction effect of myocardial infarction and obesity on left atrial functions

PURPOSE

To determine whether myocardial infarction (MI) would lead to a greater decrease in left atrial (LA) functions in subjects with than without obesity.

METHODS

A total of 310 consecutive patients were divided into four groups according to the presence or absence of obesity and MI. The functions of the LA were evaluated in terms of longitudinal deformation of the LA myocardium via 2D speckle-tracking echocardiography.

RESULTS

The adjusted analysis showed a reduction in the strain and strain rate during the reservoir and contraction phases and in the strain rate during the conduit phase in patients with MI and in subjects with obesity (P < .05). In addition, there was a significant interaction effect of obesity and MI on the strain rate during the contraction phase (P = .048).

CONCLUSIONS

There is an independent and additional interaction effect of obesity and MI on the reservoir and conduit functions of the LA. MI was more deleterious to the contraction function in subjects without than with obesity, so that the contraction function was similar in MI patients without obesity and MI patients with obesity.

Current clinical applications of speckle tracking echocardiography for assessment of left atrial function

Two-dimensional speckle tracking echocardiography (2D-STE) enables assessment of left atrial (LA) function with better reproducibility and less load dependence than those with conventional methods. Data regarding LA functions determined by 2D-STE in patients with various cardiovascular diseases have recently been accumulating. LA strain has emerged as a novel parameter with the potential of improving the diagnostic accuracy of left ventricular diastolic dysfunction and the prognostic value in patients with heart failure and stroke. Furthermore, LA dysfunction determined by 2D STE can provide incremental prognostic information to conventional echocardiographic parameters in patients with cardiovascular diseases. Hence, 2D-STE appears to be a promising technique for diagnosis and therapeutic decision-making. Data regarding LA functions determined by three-dimensional speckle tracking echocardiography (3D-STE) have also been accumulating. Here, I review recent studies, especially those published after 2016, on clinical applications of LA function assessed by 2D-STE and 3D-STE and summarize the remaining problems to be solved for improving the clinical utility of these techniques.

Assessment of the ability of the CHA2DS2-VASc scoring system to grade left atrial function by 2D speckle-tracking echocardiography

Background

The CHA₂DS₂-VASc scoring system is correlated with left atrial (LA) reservoir function in patients with atrial fibrillation (AF) rhythm or paroxysmal AF. We assessed the ability of CHA₂DS₂-VASc to grade LA function in patients with sinus rhythm who were candidates for coronary artery bypass grafting (CABG).

Methods

This cross-sectional study recruited 340 consecutive candidates for CABG and categorized them according to their CHA₂DS₂-VASc scores as mild-, moderate-, and high-risk score groups with 34 (10%), 83 (24%), and 223 (66%) patients, respectively. LA function was evaluated via 2D speckle-tracking echocardiography in terms of global longitudinal strain and strain rate during the reservoir, conduit, and contraction phases. In-hospital mortality, postoperative AF, prolonged intensive care unit (ICU) stay, and prolonged mechanical ventilation were assessed.

Results

LA strain and strain rate during the reservoir phase was statistically significantly lower in the high-risk score group than the low- and moderate-risk score groups (27.8 ± 6.9% vs 31.0 ± 5.0% vs 29.8 ± 6.1%, respectively; P = 0.004 and 2.6 ± 0.7 s⁻¹ vs 2.9 ± 0.6 s⁻¹ vs 2.9 ± 0.6 s⁻¹, correspondingly; P = 0.009) and regarding LA strain and strain rate during the conduit phase (9.7 [7.1–12.5]% vs 12.9 [9.4–15.1]% vs 11.5 [9.1–13.8]%, correspondingly; P < 0.001 and 2.1 [1.6–2.7] s⁻¹ vs 2.8 [2.4–3.6] s⁻¹ vs 2.6 [2.2–3.0] s⁻¹, respectively; P < 0.001). In addition, LA strain rate during the conduit phase was lower in the moderate-risk score group than the low-risk score group. After adjustments for possible confounders, these differences remained statistically significant. The risk of postoperative AF and prolonged ICU stay was highest in the high-risk score group (relative risk = 9.67 (1.31–71.43) and 8.05 (1.08–60.16), respectively; P = 0.026 and P = 0.042, respectively).

Conclusions

LA reservoir and conduit functions decreased in the high-risk score group, which was accompanied by an increased risk of postoperative AF and prolonged ICU stay.

Interaction Effect of Diabetes and Acute Myocardial Infarction on the Left Atrial Function as Evaluated by 2-D Speckle-Tracking Echocardiography

The aim of the study described here was to investigate, using 2-D speckle-tracking echocardiography, whether myocardial infarction (MI) leads to diminished left atrial function in diabetic patients by comparison with non-diabetic patients. A total of 310 consecutive patients were divided into four groups based on the presence or absence of diabetes mellitus (DM) and acute ST-elevation MI. In the adjusted analysis, systolic and early diastolic strain and strain rate were reduced in the diabetic patients. Additionally, all deformation markers were impaired in the patients with MI. The DM-MI interaction was not statistically significant. Although reservoir, conduit and contraction functions of the left atrium were reduced in the patients with MI, left atrial reservoir and conduit functions were decreased in the diabetic patients. The reduction in left atrial function caused by MI was similar for diabetic and non-diabetic patients. Thus, DM and MI additively damaged left atrial function.