Normal reference values for left atrial strains and strain rates in school children assessed using two-dimensional speckle-tracking echocardiography

Clinical Predictors of Subacute Myocardial Dysfunction in Multisystem Inflammatory Syndrome in Children (MIS-C) Associated with COVID-19

Multisystem Inflammatory Syndrome in Children (MIS-C) often involves a post-viral myocarditis and associated left ventricular dysfunction. We aimed to assess myocardial function by strain echocardiography after hospital discharge and to identify risk factors for subacute myocardial dysfunction. We conducted a retrospective single-center study of MIS-C patients admitted between 03/2020 and 03/2021. Global longitudinal strain (GLS), 4-chamber longitudinal strain (4C-LS), mid-ventricular circumferential strain (CS), and left atrial strain (LAS) were measured on echocardiograms performed 3-10 weeks after discharge and compared with controls. Among 60 MIS-C patients, hypotension (65%), ICU admission (57%), and vasopressor support (45%) were common, with no mortality. LVEF was abnormal (< 55%) in 29% during hospitalization but only 4% at follow-up. Follow-up strain abnormalities were prevalent (GLS abnormal in 13%, 4C-LS in 18%, CS in 16%, LAS in 5%). Hypotension, ICU admission, ICU and hospital length of stay, and any LVEF < 55% during hospitalization were factors associated with lower strain at follow-up. Higher peak C-reactive protein (CRP) was associated with hypotension, ICU admission, total ICU days, and with lower follow-up GLS (r = - 0.55; p = 0.01) and CS (r = 0.41; p = 0.02). Peak CRP < 18 mg/dL had negative predictive values of 100% and 88% for normal follow-up GLS and CS, respectively. A subset of MIS-C patients demonstrate subclinical systolic and diastolic function abnormalities at subacute follow-up. Peak CRP during hospitalization may be a useful marker for outpatient cardiac risk stratification. MIS-C patients with hypotension, ICU admission, any LVEF < 55% during hospitalization, or a peak CRP > 18 mg/dL may warrant closer monitoring than those without these risk factors.

Left atrial strain in fetal echocardiography - could it be introduced to everyday clinical practice?

OBJECTIVES

Prenatal cardiology is a part of preventive cardiology based on fetal echocardiography and fetal interventional cardiology, which facilitates treatment of congenital heart defects (CHD) in pediatric patients and consequently in adults. Timely prenatal detection of CHD plays a pivotal role in facilitating the appropriate referral of pregnant women to facilities equipped to provide thorough perinatal care within the framework of a well-structured healthcare system. The aim of this paper is to highlight the role of left atrial strain (LAS) in prenatal evaluation of fetal heart and prediction of structural and functional disorders.

METHODS

We conducted a comprehensive literature review searching PubMed for articles published from inception up until August 2023, including the search terms "left atrial strain", "fetal echocardiography", and "prenatal cardiology" combined through Boolean operators. In addition, references lists of identified articles were further reviewed for inclusion.

RESULTS

Our review underscores the significance of LAS parameters in fetal echocardiography as a screening tool during specific gestational windows (starting from 11 to 14 weeks of gestation, followed by better visualization between 18 and 22 weeks of gestation). The left atrial strain technique and its parameters serve as valuable indicators, not only for identifying cardiac complications but also for predicting and guiding therapeutic interventions in cases of both cardiac and noncardiac pregnancy complications in fetuses. Evidence suggests establishment of second-trimester reference strain and strain rate values by speckle-tracking echocardiography in the healthy fetal cohort is essential for the evaluation of myocardial pathologies during pregnancy.

CONCLUSIONS

Finding of LAS of fetal heart is feasible and probably can have potential for clinical and prognostic implications.

Postoperative evaluation of left atrial stiffness in patients with congenital heart diseases

Left atrial (LA) stiffness is one of the most important factors involved in LA remodeling. LA stiffness has rarely been studied postoperatively in patients with congenital heart diseases (CHDs). This study aimed to evaluate LA stiffness in CHD patients postoperatively. Seventy-five patients (CHDs, 67; controls, 8; age range, 10-41 years) who underwent cardiac catheterization at our institution were included in this study. From the pulmonary artery wedge pressure waveform obtained during cardiac catheterization, the pressure range between the v wave and x trough was determined, and this value was divided by the LA reservoir strain obtained by echocardiography to calculate LA stiffness, as previously reported. LA stiffness was significantly higher in postoperative CHD patients than in controls (0.28 ± 0.17 vs. 0.13 ± 0.03, p = 0.001). Nineteen of 52 (37%) patients in their teens, 8 of 11 (73%) patients in their 20 s, and 1 of 4 (25%) patients aged > 30 years had elevated LA stiffness values. In particular, all patients with an LA reservoir strain < 20% had elevated LA stiffness. In postoperative CHD patients, LA stiffness was frequently elevated from a young age. CHD patients with elevated LA stiffness should be cautious of possible LA dysfunction in the future.

Left atrial strain analysis in the realm of pediatric cardiology: Advantages and implications

BACKGROUND

Left atrial (LA) strain analysis has emerged as a noninvasive technique for assessing LA function and early detection of myocardial deformation. Recently, its application has also shown promise in the pediatric population, spanning diverse cardiac conditions that demand accurate and sensitive diagnostic measures.

OBJECTIVE

This research article endeavors to explore the role of LA strain parameters and contribute to the growing body of knowledge in pediatric cardiology, paving the way for more effective and tailored approaches to patient care.

METHODS

A comprehensive literature review was conducted to gather evidence from studies using echocardiographic strain imaging techniques across pediatric populations.

RESULTS

LA strain parameters exhibited greater sensitivity than conventional atrial function indicators, with early detection of diastolic dysfunction and LA remodeling in pediatric cardiomyopathy, children with multisystem inflammatory syndrome, rheumatic heart disease, as well as childhood renal insufficiency and obesity offering prognostic relevance as potential markers in these pediatric subpopulations. However, there remains a paucity of evidence concerning pediatric mitral valve pathology, justifying further exploration.

CONCLUSION

LA strain analysis carries crucial clinical and prognostic implications in pediatric cardiac conditions, with reliable accuracy and sensitivity to early functional changes.

Assessing atrial myopathy with cardiac magnetic resonance imaging in embolic stroke of undetermined source

BACKGROUND

Left atrial myopathy has been implicated in atrial fibrillation (AF)-related stroke and embolic stroke of undetermined source (ESUS).

OBJECTIVE

To use advanced cardiac magnetic resonance (CMR) imaging techniques, including left atrial (LA) strain and 4D flow CMR, to identify atrial myopathy in patients with ESUS.

METHODS

20 patients with ESUS and no AF or other cause for stroke, and 20 age and sex-matched controls underwent CMR with 4D flow analysis. Markers of LA myopathy were assessed including LA size, volume, ejection fraction, and strain. 4D flow CMR was performed to measure novel markers of LA stasis such as LA velocities and the LA residence time distribution time constant (RTDtc). These markers of LA myopathy were compared between the two groups.

RESULTS

There was no significant difference in: CMR-calculated LA velocities or LA total, passive or active ejection fractions between the groups. There was no significant difference in CMR-derived reservoir, conduit or contractile average longitudinal strain between the ESUS and control groups (22.9 vs 22.6%, p=0.379, 11.2 ± 3.5 vs 12.4 ± 2.6% p=0.224, 10.8 ± 3.2 vs 10.4 ± 2.3%, p=0.625 respectively). Similarly, RTDtc was not significantly longer in ESUS patients compared to controls (1.3 ± 0.2 vs 1.2 ± 0.2, p=0.1).

CONCLUSIONS

There were no significant differences in any CMR marker of atrial myopathy in ESUS patients compared to healthy controls, likely reflecting the multiple possible aetiologies of ESUS suggesting that the role LA myopathy plays in ESUS is smaller than previously thought.

The Assessment of Myocardial Longitudinal Strain in a Paediatric Spanish Population Using a New Software Analysis

BACKGROUND

Two-dimensional speckle-tracking echocardiography (2DSTE) has been present for years. However, it is underutilized due to the expertise and time requirements for its analysis. Our aims were to provide strain values in a paediatric Spanish population and to assess the feasibility and reproducibility of a new strain software analysis in our environment.

METHODS

A cross-sectional study of 156 healthy children aged 6 to 17 years. Longitudinal strain (LS) analysis of the left ventricle, right ventricle, and left atrium was performed. Feasibility and reproducibility were assessed. The associations of clinical and echocardiographic variables with strain values were investigated by multivariate analysis.

RESULTS

Mean age was 11 ± 3 years (50% female). Feasibility of LS measurement ranged from 94.2% for left ventricle global LS (LVGLS) to 98.1% for other chamber strain parameters. Strain values were 26.7 ± 2.3% for LVGLS; 30.5 ± 4.4% and 26.9 ± 4% for right ventricle free wall LS (RVFWLS) and four chambers view LS (RV4CLS) respectively; and 57.8 ± 10.5%, 44.9 ± 9.5%, and 12.9 ± 5.5% for left atrium LS reservoir phase (LALSr), conduct phase (LALScd) and contraction phase (LALSct), also respectively. Body surface area (BSA) and age presented a negative correlation with strain values. Higher values were found in females than in males, except for LALScd. Excellent intra- and inter-observer reproducibility were found for right and left ventricular strain measurement, with intraclass correlation coefficients (ICC) ranging from 0.88 to 0.98, respectively. In conclusion, we described strain values in a healthy Spanish paediatric population. LS assessment by this new strain analysis software by semi-automatic manner was highly feasible and reproducible.

Subclinical Changes in Left Heart Structure and Function at Preschool Age in Very Low Birth Weight Preterm Infants

Background

Survivors of preterm birth are at risk of long-term cardiovascular consequences. The objective of this prospective observational study was to assess left heart function at preschool age in preterm children with very low birth weight (VLBW).

Methods

We recruited children aged 5–6 years from preterm infants and full-term children. All subjects underwent conventional echocardiography and speckle-tracking echocardiography. The results were compared between the preterm and term groups.

Results

Eighty-seven VLBW preterm children and 29 term controls were included in the study. After adjusting for body surface area, the preterm group compared to the full-term group had significantly smaller left ventricular (LV) end-diastolic and end-systolic internal dimensions (31.2 vs. 33.5 mm, p = 0.048; and 20.0 vs. 21.6 mm, respectively; p = 0.024), lower LV end-diastolic and end-systolic volumes (38.8 vs. 46.3 mL, p = 0.024; and 12.8 vs. 15.6 mL, respectively; p = 0.008). Left atrial (LA) maximal and minimal volume were also significantly smaller in the preterm group (15.4 vs. 18.9 mL, p = 0.017; and 6.2 vs 7.5 mL, respectively; p = 0.018). LV global longitudinal strain (−21.4 vs. −23.2%, p < 0.0001) and systolic strain rate (−1.30 vs. −1.37 /s, p = 0.001) were significantly lower in the preterm group than in the term control group. LA longitudinal strain was decreased (43.9 vs. 52.8%, p < 0.0001) and left atrial stiffness index (0.17 vs. 0.14, p < 0.0001) was increased in preterm infants. However, all the measurements in both groups were within normal range.

Conclusions

Subclinical changes of left heart structure and function were found in VLBW infants at preschool age. Additional long-term follow-ups of the cardiovascular outcomes are needed in this vulnerable population.

Global myocardial work: A new way to detect subclinical myocardial dysfunction with normal left ventricle ejection fraction in essential hypertension patients: Compared with myocardial layer-specific strain analysis

OBJECTIVES

The aim of this study was to determine whether global myocardial work (MW), derived from non-invasive left ventricle (LV) pressure-strain loops (PSL) at rest, could predict subclinical LV myocardial dysfunction in preserved left ventricular ejection fraction (LVEF) essential hypertension (EHT) patients.

METHODS

A total of 105 untreated EHT patients and 55 normal controls were enrolled in this study. Apical 4-, 3- and 2-chamber views were acquired by two-dimensional echocardiography. The peak systolic myocardial layer-specific longitudinal strain (epimyocardial: GLSEpi; middle layer: GLSMid; and endomyocardial: GLSEndo), global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), and myocardial work efficiency (GWE) were generated by speckle-tracking echocardiography (STE).

RESULTS

The values of GLSEpi, GLSMid, and GLSEndo were significantly lower in EHT patients with LVH than in EHT patients without LVH and normal controls. GWW was significantly increased in EHT patients with LVH compared with without LVH and normal subjects, while GWE was significantly reduced in EHT patients with LVH compared with without LVH and normal subjects. ROC analysis showed that combined global MW values were a more sensitive predictor for detecting the accuracy of LV subclinical dysfunction in EHT patients than layer-specific GLS.

CONCLUSION

From the research, we conclude that global MW is more sensitive to layer-specific GLS in its ability to detect subclinical LV dysfunction even in EHT patients even without LVH.

Impact of left ventricular ejection fraction and preoperative hemoglobin level on perioperative adverse cardiovascular events in noncardiac surgery

The prediction of a perioperative adverse cardiovascular event (PACE) is an important clinical issue in the medical management of patients undergoing noncardiac surgery. Although several predictors have been reported, simpler and more practical predictors of PACE have been needed. The aim of this study was to investigate the predictors of PACE in noncardiac surgery. We retrospectively analyzed 723 patients who were scheduled for elective noncardiac surgery and underwent preoperative examinations including 12-lead electrocardiography, transthoracic echocardiography, and blood test. PACE was defined as cardiac death, non-fatal myocardial infarction, unstable angina, congestive heart failure, arrhythmia attack that needs emergency treatment (rapid atrial fibrillation, ventricular tachycardia, and bradycardia), acute pulmonary embolism, asystole, pulseless electrical activity, or stroke during 30 days after surgery. PACE occurred in 54 (7.5%) of 723 patients. High-risk operation (11% vs. 3%, p = 0.003) was more often seen, left ventricular ejection fraction (LVEF) (55 ± 8% vs. 60 ± 7%, p = 0.001) and preoperative hemoglobin level (11.8 ± 2.2 g/dl vs. 12.7 ± 2.0 g/dl, p = 0.001) were lower in patients with PACE compared to those without PACE. By multivariate logistic regression analysis, high-risk operation (odds ratio (OR): 7.05, 95% confidence interval (CI) 2.16-23.00, p = 0.001), LVEF (OR 1.06, every 1% decrement, 95% CI 1.03-1.09, p = 0.001), and preoperative hemoglobin level (OR 1.22, every 1 g/dl decrement, 95% CI 1.07-1.39, p = 0.003) were identified as independent predictors of PACE. Receiver operating characteristic analysis demonstrated that LVEF of 58% (sensitivity = 80%, specificity = 61%, area under the curve (AUC) = 0.723) and preoperative hemoglobin level of 12.2 g/dl (sensitivity = 63%, specificity = 64%, AUC = 0.644) were optimal cut-off values for predicting PACE. High-risk operation, reduced LVEF, and reduced preoperative hemoglobin level were independently associated with PACE in patients undergoing noncardiac surgery.

Assessment of visit-to-visit variability in systolic blood pressure over 5 years and phasic left atrial function by two-dimensional speckle-tracking echocardiography

Visit-to-visit variability in systolic blood pressure (VVV-SBP) has been associated with increased cardiac events. Hence, volume analysis by two-dimensional speckle-tracking echocardiography (2-DSTE) allows physicians to easily measure phasic left atrial (LA) function. However, the relationship of VVV-SBP and functional deformation of the left atrium with patients' clinical outcome is unclear. The aim of the study was to investigate the relationship between phasic LA function and VVV-SBP. The subjects were 70 male participants in whom 2-DSTE was performed to measure blood pressure at health check-ups every year for 5 years. The standard deviation of systolic blood pressure (SBP) was calculated to assess VVV-SBP. The average SBP (Ave-SBP) was also assessed. Total emptying function (EF) (reservoir function), passive EF (conduit function), and active EF (booster pump function) of the left atrium were calculated to evaluate phasic LA function by 2-DSTE. The Pearson correlation, simple regression analysis, and multivariate logistic regression analysis were used in data analysis. Participants' mean age was 50 ± 10 years, and 16 participants had hypertension. VVV-SBP correlated with total EF (r =  - 0.30, p = 0.014) and active EF (r =  - 0.35, p = 0.003). There was no correlation between the standard deviation of SBP and passive EF (r =  - 0.10, p = 0.39). Ave-SBP had no significant relationship with total EF (r =  - 0.06, p = 0.62), passive EF (r =  - 0.08, p = 0.50), or active EF (r =  - 0.03, p = 0.78). Active EF was also associated with VVV-SBP in multiple regression analysis. The active EF was significantly decreased in the highest quartile of VVV-SBP. Despite the small sample size of our study, the VVV-SBP showed a relationship with the phasic LA function. Our findings suggest that high VVV-SBP is noted to be associated with cardiovascular risk including a deterioration of LA function in clinical practice.