Mitral early-diastolic inflow peak velocity (E)-to-left atrial strain ratio as a novel index for predicting elevated left ventricular filling pressures in patients with preserved left ventricular ejection fraction

Incremental diagnostic and prognostic utility of left atrial deformation in heart failure using speckle tracking echocardiography

Left atrium (LA) is a very important component of cardiovascular performance. The assessment of LA function has gathered the interest with expanding research supporting the utility as a biomarker for outcomes in heart failure (HF). Echocardiography is the main imaging modality which helps in a qualitative and quantitative assessment of the LA size and function. Recent advances in probe technology and software analysis have provided a better understanding of LA anatomy, physiology, pathology, and function. A variety of parameters have been defined as markers of LA function but there is no single parameter that best defines LA function. Speckle tracking echocardiography-derived analysis of LA deformation provides a window on all phases of LA function (reservoir, conduit, and booster pump). There is accumulative published data that supported the diagnostic and prognostic values of LA deformation integration during echo assessment of LA in HF. This review article summarized the clinical utility of LA deformation that may help in prediction, diagnosis, categorization, risk stratification, and guiding the proper selection of therapy in HF patients in daily practice.

Effect of volume infusion on left atrial strain in acute circulatory failure

BACKGROUND

Left atrial strain (LAS) is a measure of atrial wall deformation during cardiac cycle and reflects atrial contribution to cardiovascular performance. Pathophysiological significance of LAS in critically ill patients with hemodynamic instability has never been explored. This study aimed at describing LAS and its variation during volume expansion and to assess the relationship between LAS components and fluid responsiveness.

METHODS

This prospective observational study was performed in a French ICU and included patients with acute circulatory failure, for whom the treating physician decided to proceed to volume expansion (rapid infusion of 500 mL of crystalloid solution). Trans-thoracic echocardiography was performed before and after the fluid infusion. LAS analysis was performed offline. Fluid responsiveness was defined as an increase in velocity-time integral (VTI) of left ventricular outflow tract ≥ 10%.

RESULTS

Thirty-eight patients were included in the final analysis. Seventeen (45%) patients were fluid responders. LAS analysis had a good feasibility and reproducibility. Overall, LAS was markedly reduced in all its components, with values of 19 [15 - 32], -9 [-19 - -7] and - 9 [-13 - -5] % for LAS reservoir (LASr), conduit (LAScd) and contraction (LASct), respectively. LASr, LAScd and LASct significantly increased during volume expansion in the entire population. Baseline value of LAS did not predict fluid responsiveness and the changes in LAS and VTI during volume expansion were not significantly correlated.

CONCLUSIONS

LAS is severely altered during acute circulatory failure. LAS components significantly increase during fluid administration, but cannot be used to predict or assess fluid responsiveness.

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

BACKGROUND

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

MAIN BODY

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

CONCLUSION

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

Correlation between left atrial strain and left ventricular diastolic function in hypertensive patients

OBJECTIVES

Early detection of asymptomatic diastolic dysfunction is essential to prevent the development of heart failure in hypertensive patients. Current studies suggest that left atrial strain contributes to the evaluation of left ventricular diastolic function, but there are fewer studies on the correlation between left atrial strain and diastolic function in hypertensive patients. In this study, we applied a two-dimensional speckle tracking technique to evaluate the changes in left atrial strain in hypertensive patients, and to investigate the relationship between left atrial strain and left ventricular diastolic function.

METHODS

A total of 82 hypertensive patients who were visited the Department of Cardiology at the Third Xiangya Hospital of Central South University from July 2021 to January 2022, were enrolled for this study, and 59 healthy subjects served as a control group. According to the number of left ventricular diastolic function indexes recommended by the 2016 American Society of Echocardiography Diastolic Function Guidelines (mitral annular e´ velocity: Septal e´<7 cm/s, lateral e´<10 cm/s, E/e´ ratio>14, left atrial volume index>34 mL/m2, peak tricuspid regurgitation velocity>2.8 m/s), the hypertensive patients were divided into 3 groups: Group Ⅰ (0 index, n=36 ), Group Ⅱ (1 index, n=39), and Group Ⅲ (2 indexes, n=7). Two-dimensional speckle tracking technique was used to measure left atrial reservoir strain (LASr), conduit strain, and contraction strain, and to analyze the correlation between left atrial strain and left ventricular diastolic function in hypertensive patients.

RESULTS

The LASr, left atrial conduit strain (LAScd), and LASr/(E/septal e´) of the hypertension group were lower than those of the control group, and E/LASr was higher than that of the control group. There was no significant difference in left atrium volume index between the 2 groups (P>0.05). Compared with Group Ⅰ, LASr, LAScd, and LASr/(E/septal e´) were decreased in Group Ⅱ and Group Ⅲ, LASr/(E/septal e´) was also decreased in Group Ⅲ compared with Group Ⅱ (all P<0.05). Compared with Group Ⅰ, E/LASr was increased in Group Ⅲ. LASr was positively correlated with septal e´, lateral e´, E, and E/A, and negatively correlated with E/septal e´.

CONCLUSIONS

The changes of left atrial function in patients with early hypertension are earlier than those of left atrial structure. Left atrial strain and its combination with conventional ultrasonographic indices [LASr/(E/septal e´)] of diastolic function are potentially useful in assessing left ventricular diastolic function in hypertensive patients.

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.

The novel left atrial strain parameters in diagnosing of heart failure with preserved ejection fraction

Objectives

We sought to evaluate the ability of the novel LA strain parameters to discriminate patients with heart failure with preserved ejection fraction (HFpEF) from individuals with risk factors of HFpEF.

Methods and results

A total of n = 389 patients with risk factors for HFpEF finally was prospectively enrolled into the study, 66 of them were diagnosed with HFpEF by the 2021 ESC HF guidelines. Fifty‐five patients were undergone left ventricular catheterization and simultaneous transthoracic echocardiography was performed, 35 of them with elevated left ventricular end‐diastolic pressure (LVEDP). Left atrial reservoir strain (LASr) was measured in all patients. LA filling index was defined as the ratio of mitral E and LASr and LA stiffness index was calculated as E/e′/LASr. Compared with the patients in the normal LVEDP subgroup, those in the elevated LVEDP subgroup showed significantly higher LA filling index, LA stiffness index, and LAVI/LASr. The receiver‐operating characteristic curve (ROC) analysis showed LASr (area under curve [AUC] .840), LA filling index (AUC .843), LA stiffness index (AUC .766), and LAVI/LASr (AUC .755) had good diagnostic accuracy for elevated LVEDP. Inter‐technique agreement analysis showed the novel algorithms with LA strain parameters had good agreement with the invasive LVEDP measurement, better than the 2016 ASE/SCAI algorithms (kappa .711 vs. .101). Furthermore, compared with patients without HFpEF, LASr was lower in HFpEF, LA filling index, LA stiffness index, and LAVI/LASr was higher in patients with HFpEF. ROC analysis showed the novel LA strain parameters with good accuracy (AUC .756 to .821) non‐inferior to conventional echocardiographic parameters could identify HFpEF, and LA stiffness index (AUC .821) was the best one.

Conclusion

The novel LA strain parameters could be of potential usefulness in estimating LVEDP and incorporated into the 2016 EACVI/ASE criteria would improve the diagnostic efficiency. The novel LA strain parameters with good accuracy non‐inferior to conventional echocardiographic parameters could discriminate HFpEF from patients with risk factors of HFpEF.