Longitudinal Strain Research Articles

EXPERIMENTAL ANALYSIS OF POISSON RATIO ON METAMATERIALS MANUFACTURED FROM CRUMPLED ALUMINUM FOIL SUBJECTED TO UNIAXIAL COMPRESSION

In this work experimental results are presented concerning the auxetic behavior of a crumpled metamaterial manufactured with aluminum foil, so far such experimental evidence has not been reported by other authors. Thus, 2D digital image correlation (DIC) was used to make full field measurements of longitudinal and transverse strains on the surface of crumpled aluminum specimens under axial compression; it was no possible to use conventional methods on the measurements of strains, such as strain gages or extensometers, due to the irregular topography on the surface of the specimens. The obtained results exhibit the auxetic nature of the aluminum crumpled material, with Poisson´s ratio values that vary from ?=-0.17 to ?=-0.02 for relative densities in the range ?_r=0.07 to ?_r=0.21. Keywords: Auxetic, Digital Image Correlation, Crumpled material, Poisson, Computer vision system.

Absence of cardiac impairment in patients after SARS-CoV-2 infection: a long-term follow-up study.

Concerns exist that long-term cardiac alterations occur after SARS-CoV-2 infection, particularly in patients who were hospitalized in the acute phase or who remain symptomatic. This study investigates potential long-term functional and morphological alterations after SARS-CoV-2 infection. The authors of this study investigated patients after SARS-CoV-2 infection by using a mobile 1.5-T clinical magnetic resonance scanner for cardiac alterations. Cardiac function and dimensions were assessed using a highly efficient cardiac magnetic resonance (CMR) protocol, which included cine sequences, global longitudinal and circumferential strain assessed by fast-Strain-ENCoded imaging (fSENC), and T1 and T2 mapping. We assessed symptoms through a questionnaire. Patients were compared with a control group matched for age, gender, body mass index, and body surface area. Median follow-up time was 395 (192-408) days. The final population included 183 participants (age 48.4±14.3 years, 48.1% male). During the acute phase of SARS-CoV-2 infection, 27 patients were hospital-admitted. 42 patients reported persistent symptoms (shortness of breath, chest pain, palpitations, or leg edema), and 63 reported impaired exercise tolerance. Left ventricular functional and morphological parameters were within the normal range. T1- and T2-relaxation times were also within the normal range, indicating that the presence of myocardial edema or fibrosis were unlikely. Persistently symptomatic patients showed a slightly reduced indexed LV-SV. Functional parameters remained normal in patients who were hospitalized for SARS-CoV-2, persistently symptomatic, or with ongoing impaired exercise tolerance. Irrespective of ongoing symptoms or severity of prior illness, patients who have recovered from SARS-CoV-2 infection, demonstrate normal functional and morphological cardiac parameters. Long-term cardiac changes due to SARS-CoV-2 infection appear to be rare.

The impact of exercise intensity and duration for swim training-induced adaptations in cardiac structure and function in women with mild hypertension.

This study aimed to investigate the impact of swim training intensity and duration on cardiac structure and function in mildly hypertensive women. Sixty-two mildly hypertensive women were randomized to 15 weeks of either (1) high-intensity swimming (HIS, n = 21), (2) moderate-intensity swimming (MOD, n = 21) or (3) control (CON, n = 20). Training sessions occurred three times per week. Cardiac measurements were conducted using echocardiography pre- and post-intervention. Both the HIS and MOD groups demonstrated significant within-group increases in left ventricular mass: 7.3% [1.2; 13.2] (p = 0.02) for HIS and 6.2% [0.5; 11.8] (p = 0.03) for MOD. The MOD group also demonstrated a significant increase in left ventricular internal dimension at end-diastole by 2.4% [0.2; 4.6] (p = 0.03).Post-hoc analysis of diastolic function markers revealed reduced mitral valve A velocity in both HIS (-14% [-25; -3], p = 0.02) and MOD (-13% [-23; -3], p = 0.01), leading to increased mitral valve E/A ratios of 27% [10; 47] (p = 0.003) and 22% [5; 40] (p = 0.01), respectively. Additionally, only MOD demonstrated increased left atrial diameter of 4.9% [0.7; 9.1] (p =0.02). A significant time×group effect (p = 0.02) existed for global longitudinal strain, which increased by 1.6% [0.2; 3.0] (p = 0.03) in MOD only. In conclusion, swim training for 15 weeks increased left ventricular mass and improved markers of diastolic function in mildly hypertensive women. These independent of exercise intensity and duration in mildly hypertensive women.

Dyssynchronous Fetal Heart Failure in Maternal Diabetes: Evaluation with Speckle Tracking Echocardiography and Novel M-Mode Software

ObjectivesThis study aimed to investigate dyssynchronous heart failure in fetuses of mothers with diabetes mellitus (FDM) and fetal controls (FC) using two-dimensional speckle tracking echocardiography (2D-STE) and novel M-mode prototype software (PS). MethodsIn this cohort study 174 fetuses were analyzed, 87 in the FDM-cohort and 87 gestational age-matched fetuses in the FC-cohort. A subgroup of 38 fetuses formed the final case group, with a high median frame rate of approximately 160 frames/s. Using 2D Cardiac Performance Analysis software (TOMTEC, Unterschleissheim, Germany) we measured global longitudinal strain (GLS). TOMTEC PS detected annular displacement by assessing an artificial M-mode on the previously generated tracking. Dyssynchrony (DYS) was calculated as the inter- and intraventricular difference in time to peak GLS or annular displacement. ResultsGreater DYS was observed in all basal myocardial measurement sites and software between FDM-cohort compared to FC-cohort and no significant correlation was found between DYS measurements and gestational age. Intraventricular DYS between the basal segments was statistically significant (all p ≤ 0.036, Wald test of univariate regression models). The PS performed best in DYS measurements identifying right ventricular DYS as potentially predicting FDM (FDM: median, 18.5 (interquartile range [IQR], 13.9–25.0) ms vs. FC: median, 2.7 [IQR, 1.5–3.5] ms; p < 0.001). ConclusionIncreased intraventricular DYS demonstrated an impact of maternal diabetes mellitus on fetal hearts independent of gestational age. The prototype M-mode method identified cardiac dysfunction with higher accuracy than the conventional analysis. High-quality echocardiographic image acquisition is imperative for clinical application of 2D-STE and related advanced technologies.

Atrial fibrillation substrate and impaired left atrial function: a cardiac MRI study.

Structural and fibrotic remodelling is a well-known contributor to the atrial fibrillation (AF) substrate. Epicardial adipose tissue (EAT) is increasingly recognized as a contributor through electrical remodelling in the atria. We aimed to assess the association of LA fibrosis and EAT with LA strain and function using cardiac magnetic resonance (CMR) imaging in patients with AF. LA fibrosis was assessed using late gadolinium enhancement CMR, LA EAT was assessed using the fat-water separation Dixon sequence, and feature tracking was applied to assess global longitudinal strain in its three components [reservoir (GLRS), conduit (GLCdS), and contractile (GLCtS)]. LA emptying fraction and LA volume were measured using the cine sequences. All CMR images were acquired in sinus rhythm. One hundred one AF patients underwent pre-ablation CMR (39% female, average age 62 years). LA fibrosis was negatively associated with the three components of global longitudinal strain (GLRS: R = -0.35, P < 0.001; GLCdS: R = -0.24, P = 0.015; GLCtS: R = -0.2, P = 0.046). Out of the different sections of the LA, fibrosis in the posterior and lateral walls was most negatively correlated with GLRS (R = -0.32, P = 0.001, and R = -0.33, P = 0.001, respectively). LA EAT was negatively correlated with GLCdS (R = -0.453, P < 0.001). LA fibrosis was negatively correlated with LA emptying fraction but LA EAT was not (R = -0.27, P = 0.007, and R = -0.22, P = 0.1, respectively). LA EAT and fibrosis were both positively correlated with LA volume (R = 0.38, P = 0.003, and R = 0.24, P = 0.016, respectively). LA fibrosis, a major component of the AF substrate, and EAT, an important contributor, are associated with a worsening LA function through strain analysis by CMR.

Echocardiographic Assessment of Cardiac Remodeling According to Obesity Class

Evidence supports the existence of cardiac remodeling in obesity, but no standard diagnostic criteria has been proposed or validated.The objective of this study was to identify echocardiographic features of cardiac remodeling according to obesity class and assess the effect of non-surgical weight loss on cardiac structure and function.A total of 120 patients were divided according to their obesity class (Group 1: BMI 18.5-24.9; Group 2: 25-29.9; Group 3: 30-39.9; Group 4: >40) and underwent cross-sectional transthoracic echocardiography. Echocardiographic parameters of cardiac chamber quantification and function were compared between the 4 groups. Echocardiographic parameters were compared pre- and post-non-surgical weight loss in a subgroup of patients. Overall, there was an incremental increase in left ventricular (LV), left atrial (LA), and right ventricular dimensions, LV mass and LV stroke volume (all p<0.0001) across obesity classes. There was no significant difference in LV ejection fraction or right ventricular systolic function as assessed by tricuspid annular plane systolic excursion (TAPSE) but a significant decrease in global longitudinal strain (BMI 18.5-24.9: 22.8%±1.7%; BMI 25-29.9: 22.0%±1.4%; BMI 30-39.9: 20.8%±1.1%; BMI >40: 20.6%±1.3%, p<0.0001) and left atrial strain (BMI 18.5-24.9: 37.7%±2.3%; BMI 25-29.9: 32.8%±2.1%; BMI 30-39.9: 31.5%±1.8%; BMI >40: 29.0%±2.8%, p<0.0001). Allometric height-indexed LV and LA dimensions increased with increasing BMI class (p<0.0001). Echocardiographic parameters did not change significantly after non-surgical weight loss.In conclusion, echocardiographic features can be described according to obesity class. Allometric height indexation may better reflect cardiac remodeling in obesity in comparison to BSA indexation. Non-surgical weight loss was not associated with significant changes in cardiac chamber dimensions and function.

Preoperative left atrial size and functions are predictors of left atrial reverse remodelling after mitral valvuloplasty for myxomatous mitral valve disease in dogs

ObjectivesThe objective of this study was to determine alterations in left atrial size, function, and determinants of left atrial reverse remodelling (LARR) after mitral valvuloplasty (MVP) in dogs with myxomatous mitral valve disease (MMVD). AnimalsThirty-seven dogs undergoing MVP. Materials and MethodsEchocardiographic parameters, including left atrial (LA) strain, were evaluated at baseline, during the early postoperative period (within two weeks), and at one and three months postoperatively. Patients were divided into two groups based on the attainment of LARR, defined as a left atrial to aortic root ratio (LA:Ao) < 1.6 at three months. The predictors of LARR were analysed using univariate logistic regression analysis. ResultsLA:Ao significantly decreased in the early postoperative period (median 1.68; lower and upper quartile 1.54–1.92) compared to baseline (2.41; 2.00–2.80), with a further significant reduction observed at three months (1.46; 1.34–1.63). LARR was achieved in 27 (73%) patients. Baseline LA:Ao was higher, and peak atrial longitudinal strain (PALS) and peak atrial construction strain (PACS) were lower in the non-LARR group than in the LARR group. Among the baseline parameters, PACS was the strongest predictor of LARR (area under the curve, 0.837). ConclusionsFollowing MVP, the LA size decreased in the early postoperative period and continued to decrease over three months of follow-up. A low PACS score was the most reliable predictor of inadequate LARR. Further studies are necessary to determine the relationship between LARR, prognosis, and the optimal timing for surgical intervention.

Echocardiographic Markers of Early Left Ventricular Dysfunction in Asymptomatic Aortic Regurgitation: Is It Time to Change the Guidelines?

The ideal timing for surgery in asymptomatic chronic aortic regurgitation (AR) remains unclear. New thresholds for left ventricular ejection fraction (LVEF), left ventricular (LV) indexed end-systolic volume (iESV), and global longitudinal strain (GLS) have been associated with mortality in these patients. These represent markers of early LV dysfunction. The authors sought to assess the relationship between these markers (LVEF<60%, iESV≥45mL/m2, and GLS worse than -15%) and mortality, comparing them to Class I/IIa American College of Cardiology/American Heart Association guideline recommendations and absence of any of these. A total of 673 asymptomatic patients with chronic clinically significant (≥ moderate-severe) AR between 2004 and 2019 at a single referral center were retrospectively analyzed. The primary study outcome was all-cause mortality. Mean age was 57 ± 17 years, 97 (14%) were female, 293 (45%) had hypertension, and 273 (41%) had an abnormal number of valve cusps. Aortic valve replacement was performed in 281 (48%) patients, and 69 (10%) died while under surveillance (without aortic valve replacement). LVEF<60% was present in 296 (44%) patients, 122 (25%) of 482 had GLS worse than -15%, and 261 (39%) had iESV≥45mL/m2. Mortality under surveillance was highest when Class I/IIa recommendations were present (HR: 4.22; 95%CI: 2.15-8.29), followed by the presence of 1 or more markers of early LV dysfunction (HR: 2.18; 95%CI: 1.21-3.92); no markers was used as the reference (all, P< 0.05). LVEF showed the strongest association with mortality, statistically slightly better than GLS and iESV. In the absence of ClassI/IIa recommendations, 1 marker of early LV dysfunction was associated with higher, although not statistically significant, mortality compared with no markers (P=0.063), followed by 2 markers; highest mortality was when all 3markers were present (HR: 5.46; 95%CI: 2.51-11.90; P< 0.001). Patients with asymptomatic clinically significant chronic AR incur a survival penalty when Class I/IIa guideline recommendations are attained. In patients without these recommendations, at least 2 markers of early LV dysfunction identify those with higher mortality risk who may benefit from early surgery.

Reference intervals of two-dimensional speckle tracking derived endocardial global longitudinal strain analysis in 132 healthy cats

Reference intervals of two-dimensional speckle tracking derived endocardial global longitudinal strain analysis in 132 healthy cats

Early Detection of Left Ventricular Dysfunction With Machine Learning-Based Strain Imaging in Aortic Stenosis Patients.

Aortic stenosis (AS) is a common cardiovascular condition where early detection of left ventricular (LV) dysfunction is essential for timely intervention and optimal management. Current echocardiographic measurements, such as ejection fraction (EF), are insensitive to minor changes in LV function, and strain imaging is typically limited to the global longitudinal strain (GLS) parameter due to robustness issues. This study introduces a novel, fully automatic algorithm to enhance the detection of LV dysfunction in AS patients using multiple strain imaging parameters. We applied supervised machine-learning techniques to classify data from 82 severe AS patients, 96 chest pain subjects, and 319 healthy volunteers. Our model significantly outperformed EF and GLS in distinguishing AS patients from healthy volunteers (area under the curve [AUC] = 0.97 vs. 0.88 and 0.82, respectively). It also surpassed EF and GLS in differentiating AS patients from chest pain subjects (AUC = 0.95 vs. 0.90 and 0.55, respectively). This novel, clinically interpretable model leverages the potential of strain imaging to enhance diagnostic accuracy and guide clinical decision-making in LV dysfunction, thereby improving clinical practice.

Ferric carboxymaltose reduces the burden of arrhythmic events in heart failure with reduced ejection fraction: the role of the non-invasive arrhythmic biomarkers

BackgroundTreating iron deficiency (ID) with ferric carboxymaltose (FCM) in patients with heart failure with reduced ejection fraction (HFrEF) enhances morbidity, quality of life (QoL), and exercise capacity. MethodsThis single center, prospective follow-up study aims to assess FCM's impact on arrhythmic events and non-invasive markers in HFrEF patients with cardiac implantable electronic devices (CIEDs) and ID. Symptomatic HFrEF patients with ID and CIEDs scheduled for IV FCM were followed for 12-months. Arrhythmic activity was evaluated from CIEDs and non-invasive markers from Holter recordings pre- and post-FCM. Ventricular tachycardia/ventricular fibrillation (VT/VF) episodes, non-sustained VT (nsVT), late potentials (LPs), Microvolt T-wave alternans (MTWA), heart rate variability, turbulence (HRT) QTc, and premature ventricular contractions (PVCs, number and Lown and Wolf classification) were assessed. Left ventricular EF (LVEF), global longitudinal strain (LV GLS), QoL (KCCQ, EQ-5D-5L), six-minute walking distance (6MWD), peak oxygen consumption, and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) levels were also recorded. ResultsNinety-six patients in optimal medical treatment participated (median age 71.9 [12.3] years, 83% male). Post-FCM treatment, VT/VF (P=0.043) and nsVT (P<0.001) frequency decreased significantly. The Lown and Wolf classification improved (P=0.002) and predicted VT/VF episodes better than other markers (AUC 0.737, P=.001). MTWA, LPs and HRT improved statistically significantly post-FCM. Hospitalization rates and NT-proBNP levels decreased, while LVEF, LV GLS, 6MWD, QoL and peak VO2 improved statistically significantly (P<0.001). ConclusionsOur study provides real-world evidence that IV FCM led to statistically significant reduction in ventricular arrhythmic episodes, as well as an improvement in non-invasive arrhythmic markers.

Prediction Model for Fracture Toughness of Waterborne Polyurethane Modified Concrete at Different Temperatures

In certain extreme environments, the bearing capacity of concrete structures diminishes significantly as temperatures soar, simultaneously exposing them to a heightened risk of brittle cracking. The paper aims to elucidate the fracture toughness of waterborne polyurethane modified concrete (WPMC) at different temperatures. Furthermore, a predictive model for the fracture toughness of WPMC, which incorporates both temperature and the waterborne polyurethane (WP) content, is proposed. The flexural strength and fracture toughness of WPMC were tested separately at 20℃, 40℃, 60℃, and 80℃. Utilizing digital image correlation (DIC) technology, the bottom longitudinal strain of WPMC under flexural loading was analyzed. The impact of temperature and WP content on the energy absorption capacity and deformation behavior of WPMC exposed to extreme environment was also investigated. By introducing the microstructural parameters C and Cw to characterize the elastic and plastic deformations of WPMC before and after cracking, a fitting model between the microstructural parameters and temperature, WP content was established. This model enables the prediction of the fracture toughness KIC of WPMC at different temperatures by measuring Fmax.

Cardiopulmonary Physiology of Hypoxemic Respiratory Failure among Preterm Infants with Septic Shock

To examine cardiopulmonary physiological alterations associated with hypoxemic respiratory failure (HRF; fraction of inspired oxygen ≥0.60) among preterm neonates requiring vasopressors/inotropes during sepsis (septic shock). We conducted a retrospective cohort study from 2015 through 2022 at a tertiary neonatal intensive care unit. Neonates <34 weeks gestational age who had septic shock and underwent a comprehensive targeted neonatal echocardiography (TNE) ≤72 hours of sepsis onset were included. TNE findings of patients with shock and HRF were compared with those with shock without HRF. Indices of pulmonary vascular resistance (PVR), right (RV) and left (LV) ventricular systolic and diastolic function, measured using conventional, tissue Doppler imaging and speckle-tracking echocardiography, were examined. Of 52 included infants with septic shock, 19 (37%) also had HRF. Baseline characteristics were similar. On TNE, although the HRF group more frequently had bidirectional/right-to-left flow across the patent ductus arteriosus (67% vs. 33%; p=0.08), all indices of PVR and RV function were similar. However, the HRF group demonstrated reduced LV systolic function [ejection fraction: 51.8±12.3 vs. 62.6±13.0%; global peak systolic longitudinal strain -15.2±4.5 vs. -18.6±4.5%], diastolic function [early (2.3±1.0 vs. 3.6±1.2 /s) and late (2.4 (1.9, 2.6) vs. 2.8 (2.3, 3.5) /s diastolic strain rate], and higher frequency of LV output <150 ml/min/kg (44 vs. 12%); all p<0.05. Acute HRF occurring in preterm neonates with septic shock is associated with alterations in TNE measures of LV function, and not PVR or RV function. Future studies should evaluate the impact of supporting LV function in these patients.

Cardiac function at follow-up in infants treated with therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy.

Compromised myocardial function and persistent elevated pulmonary vascular resistance are common among neonates treated with therapeutic hypothermia (TH) for hypoxic-ischemic encephalopathy (HIE). There is a lack of data regarding persistence of cardiac alterations after discharge from the neonatal intensive care unit (NICU). We assessed cardiovascular profiles after NICU discharge. Echocardiogram data, including speckle-tracking echocardiography (STE), were extracted from the latest outpatient scan. Data were compared by initial amplitude-integrated encephalography (aEEG) profiles on admission [normal vs. abnormal]. In total, 70 (19%) neonates had a follow-up echocardiogram (22 with initial normal aEEG, 48 with abnormal aEEG). Age at follow-up was similar between the two groups (6.2 vs. 7.7 months, [p = 0.08]). Neonates with an initially abnormal aEEG showed more negative Right Ventricle (RV)-peak global longitudinal strain (-28.2 vs. -26.0%, [p = 0.02]), RV-peak free wall longitudinal strain rate (-1.24 vs. -1.10 [1/second], [p = 0.01]), and RV-peak free wall longitudinal strain rate (-1.50 vs. -1.27 [1/second], [p = 0.001]). These associations remained after multilinear regression analysis, indicating persistent enhanced RV contraction in the abnormal aEEG group. Neonates with initial abnormal aEEG profiles exhibited increased RV contraction after NICU discharge. Future studies should explore long-term cardiovascular follow-up of neonates with HIE, beyond the perinatal period. What is the key message of your article? Cardiac performance in hypoxic ischemic encephalopathy is linked to adverse outcomes. Survivors with an abnormal aEEG at admission showed increased right ventricular contractility at follow-up, possibly related to an adverse adaptation to the initial insult. What does it add to the existing literature? This study offers insights into long-term cardiovascular outcomes in neonates with HIE, focusing on the link between initial aEEG abnormalities and later RV function. What is the impact? The findings underscore the importance of early cardiovascular assessments and monitoring in neonates undergoing TH for HIE, potentially guiding future follow-up protocols.

Mechanical Response of Hot-Mixed Epoxy Asphalt Concrete Steel Deck Pavement Under Thermal and Load

In recent years, fatigue cracking in orthotropic steel bridge deck pavements has become a significant concern, so the investigation of the mechanical response of the pavement layer has become a central focus in pavement structure design. This experiment subjected a full-scale specimen to a constant amplitude dynamic load of 60 kN to 300 kN over 2 million cycles. Throughout the testing, a circulating water bath elevated the temperature of the pavement layer from 15 °C to 50 °C. Key locations were monitored for strain and deflection data, facilitating an investigation into the mechanical response of the epoxy asphalt pavement system under the effects of temperature and load. The results indicate that the maximum transverse strain at the bottom of the steel deck occurs at the U-rib weld aligned with the load center, reaching 190% of the initial loading strain. Meanwhile, the maximum transverse strain on the pavement surface is observed at the U-rib weld adjacent to the loaded area, measuring 167% of the initial strain. The maximum longitudinal strain is lower than the maximum transverse strain. In the load zone, the longitudinal strain between the U-ribs exceeds that at the U-rib weld. Both transverse strain and relative deflection increase as the load intensifies. The relationship between transverse strain and applied load is characterized by an exponential function, while deflection exhibits a cubic relationship with the applied load. Elevated temperatures also contribute to increased transverse strains at both the bottom of the steel deck and the pavement surface, following an exponential trend. Relative deflection is primarily influenced by the applied load and remains relatively unaffected by temperature variations. When accounting for the coupling of load and temperature, the maximum transverse strains at both the bottom of the steel deck and the pavement surface can be modeled as an exponential function of the independent variables: load and temperature.

A review of alternative measurements in strain imaging for ventricular arrhythmia prediction.

Global longitudinal strain has been established as a reliable tool to assess global left ventricular function and a marker of subclinical left ventricular dysfunction unrecognized by the ejection fraction. On the other hand, ventricular arrhythmias are the most common cause of sudden cardiac death. Their early detection is a challenge. Possible prognostic markers for the risk of ventricular arrhythmias are discussed in the literature - electrocardiographic, cardiac magnetic resonance, computed tomography, radionuclide imaging, and markers from new echocardiographic techniques. Of the latter, at this stage of knowledge, several markers have been discussed as informative for predicting ventricular arrhythmias - global longitudinal strain, radial strain and mechanical dispersion, and most recently, myocardial work. As far as we are informed, global longitudinal strain is particularly useful in patients with normal echocardiographic parameters such as left ventricular ejection fraction, left atrial diameter, left ventricular wall thickness, and aortic root. The relationship between mechanical dispersion and ventricular arrhythmias has been widely studied. The relationship has been studied more in some patient populations - heart failure, ischemic heart disease, long QT syndrome and arrhythmogenic cardiomyopathy, congenital heart disease. The role of mechanical dispersion as a predictor of ventricular arrhythmias in metabolic syndrome is scarce.

Left atrial function in uraemic patients: Four-dimensional automatic left atrial quantitative technology study.

This study aimed to evaluate the utility of left atrial volume and function in uraemic patients using four-dimensional automatic left atrial quantification (4D auto LAQ) technology. Thirty-four undialysed uraemic patients (U-ND group), 60 dialysed uraemic patients (U-D group), and 32 healthy volunteers (N group) were enrolled in our current study. Conventional echocardiographic parameters were recorded, and left atrial volume and strain parameters were analysed to determine statistical differences among the three groups. The Pearson correlation coefficient was employed to assess the relationships between left atrial ejection fraction and left atrial strain parameters. Compared to the N group, uraemic patients often displayed left atrial enlargement and left ventricular hypertrophy. Significant increases were noted in left atrial diameter, interventricular septum thickness, left ventricular posterior wall thickness, E/e', diastolic blood pressure, systolic blood pressure, left atrial minimum volume, left atrial maximum volume, left atrial pre-atrial contraction volume, left atrial emptying volume and left atrial maximum volume index (P<0.05). Conversely, the e', E/A ratio and left atrial reservoir longitudinal strain were significantly decreased (P<0.05). However, no statistically significant differences were observed in the aforementioned parameters between the U-ND and U-D groups. The absolute values of left atrial conduit longitudinal strain and left atrial conduit circumferential strain, as well as left atrial passive ejection fraction, were notably lower in the U-D group compared to the N and U-ND groups, with statistically significant differences identified among the three groups (P<0.05). Uraemic patients exhibit marked left atrial enlargement and left ventricular hypertrophy, coupled with altered atrial function, particularly ductal dysfunction in the U-D group. The 4D auto LAQ technology proves advantageous in detecting these alterations, offering a promising tool for thorough cardiac assessment in this patient cohort.

Left atrial functional changes associated with repeated catheter ablations for atrial fibrillation.

The impact of repeated atrial fibrillation (AF) ablations on left atrial (LA) mechanical function remains uncertain, with limited long-term follow-up data. This retrospective study involved 108 AF patients who underwent two catheter ablations with cardiac magnetic resonance imaging (MRI) done before and 3 months after each of the ablations from 2010 to 2021. The rate of change in peak longitudinal atrial strain (PLAS) assessed LA function. Additionally, a sub-study of 36 patients who underwent an extra MRI before the second ablation, gave us an additional time segment to evaluate the basis of change in PLAS. In the two-ablation, three MRI sub-study 1, the PLAS percent change rate was similar before and after the first ablation (r11 = -0.9 ± 3.1%/year, p = 0.771). However, the strain change rate from postablation 1 to postablation 2 was significantly worse (r12 = -23.7 ± 4.8%/year, p < 0.001). In the sub-study 2 with four MRIs, all three rates were negative, with reductions from postablation 1 to pre-ablation 2 (r22 = -13.3 ± 2.6%/year, p < 0.001) and from pre-ablation 2 to postablation 2 (r23 = -8.9 ± 3.9%/year, p = 0.028) being significant. The present study suggests that the more ablations performed, the more significant the decrease in the postablation mechanical function of the LA. The natural progression of AF (strain change from postablation 1 to pre-ablation 2) had a greater negative influence on LA mechanical function compared to the second ablation itself suggesting that second ablation in patients with recurrence after first ablation is an effective strategy even from the LA mechanical function aspect.

Normal values and distribution of ventricular global longitudinal strain in 513 healthy fetuses measured by two-dimensional speckle-tracking echocardiography: a multi-institutional cohort study.

This study aimed to determine the normal reference values and distribution of global longitudinal strain (GLS) in the right and left ventricles of healthy Japanese fetuses during pregnancy. This multi-institutional cohort study included healthy Japanese fetuses during normal pregnancies without maternal or fetal complications between 18 and 40weeks of gestation. Two-dimensional fetal echocardiographic images of the four-chamber view with a high frame rate were acquired and stored as DICOM clips. Data were collected and analyzed in a central laboratory to measure the left ventricular (LV) and right ventricular (RV) GLS using two-dimensional speckle tracking. In total, 513 fetuses were enrolled. The mean LV-GLS and RV-GLS were - 24.3% ± 3.5% and - 23.5% ± 3.7%, respectively. The magnitude of the GLS, with normal limits in both ventricles, decreased with advancing gestation. LV values were r = 0.34 (95% confidence interval, 0.27-0.42) and p < 0.0001; RV values were r = 0.33 (95% confidence interval, 0.25-0.41) and p < 0.0001. The normal values of healthy Japanese fetuses in healthy pregnancies is the first to be established by the large-scale, multi-institutional cohort study as LV-GLS of 24.3% ± 3.5% and RV-GLS of - 23.5% ± 3.7%, respectively. This can serve as a basic reference for assessing the cardiac functions in Japanese fetuses with various heart diseases.

Comparison of early postoperative left ventricular function with 3d ef and strain measurements according to graft selection

BackgroundGraft choices other than left anterior descending artery (LAD)–internal thoracic artery (ITA) anastomosis in coronary artery bypass grafting (CABG) surgery are still controversial. Although 2-dimensional transthoracic echocardiography (2D TTE) is still the most commonly used method, more is needed to diagnose myocardial dysfunction. Ventricular strain values obtained by speckle tracking echocardiography (STE) or tissue Doppler imaging (TDI) methods can much better detect subclinical changes. This study aims to detect early postoperative myocardial function changes compared to single ITA/Bilateral Internal Thoracic Artery (BITA) use by measuring 3-dimensional ejection fraction (3D EF) and ventricular strain values and comparing them according to graft preference.MethodsThe study included 35 isolated CABG patients. All patients underwent on-pump CABG via sternotomy. The patients were divided into two groups using single ITA and BITA. Preoperative and postoperative 1st-week 3D EF and ventricular strain values of the patients were calculated using semi-automatic software. The recorded data were compared and evaluated between the two groups.ResultsOf The 35 patients participating in the study, 74.3% (n = 26) were male, 25.7% (n = 9) were female, and their average age was 62.7 ± 7.9 years. Preoperative 3D EF values of the patients were 54.4 ± 8.3% and postoperative 49.5 ± 8.2%. The mean preoperative Apical Long Axis Longitudinal Strain (APLAX LS) was calculated as − 16.2 ± 5.0%, 4 Chambers Longitudinal Strain (4CH LS)–16.8 ± 4.6%, 2 Chambers Longitudinal Strain (2CH LS) − 17.0 ± 4.9%, and Global Longitudinal Ventricular Strain (GLVS) − 16.7 ± 4.2%. Postoperative strain values were measured as − 15.1 ± 4.8%, − 14.7 ± 4.9%, − 14.6 ± 5.6% and − 14.8 ± 4.6%, respectively. When the groups were evaluated within themselves, the mean preoperative 3D EF of the patients in the single ITA group was 52.5 ± 8.8%, while the postoperative mean was 47.7 ± 6.0%. In the BITA group, preoperative 3D EF was 56.3 ± 7.5 and postoperative 51.4 ± 9.8. A decrease in strain values was detected in all groups except APLAX planes.ConclusionsIn our study, no statistically significant difference was observed in terms of myocardial function changes according to the use of ITA/BITA. However, the decline in postoperative strain values of patients in the BITA group was more remarkable, and it was thought that this may be due to prolonged aortic cross clamp (CC) and cardiopulmonary bypass (CPB) times.