Longitudinal Shortening Research Articles

Left Ventricular Strains and Right Ventricular Longitudinal Shortening Are Associated in Healthy Adults—A Detailed Analysis from the Three-Dimensional Speckle-Tracking Echocardiographic MAGYAR-Healthy Study

Introduction: The right ventricle (RV) lies on the left ventricle (LV), and their shapes and movements are characteristic and significantly different. The aim of the present study was to investigate the relationship between three-dimensional speckle-tracking echocardiography (3DSTE)-derived LV strains, which represent LV contractility as quantitative features, and tricuspid annular plane systolic excursion (TAPSE) as determined by M-mode echocardiography, which represents the longitudinal movement of the RV, in healthy adults. Methods: A total of 79 healthy adults (mean age: 28.1 ± 6.3 years; 33 men) were enrolled in the present study. After two-dimensional Doppler echocardiography, 3DSTE-derived data acquisition was carried out in all cases, and detailed 3DSTE-based analysis was performed offline at a later date. Results: Reduced TAPSE was associated with increased global and basal LV radial strain (RS). Increased TAPSE was also associated not only with increased global and basal LV-RS but also with global LV longitudinal strain (LS). An increase in global LV-RS and global LV circumferential strain (CS) showed associations with other strains except for global LV-LS. An increase in global LV-LS did not show associations with other strains. Increased global LV-RS was associated with reduced TAPSE, while the degree of global LV-LS and global LV-CS did not show associations with TAPSE. Conclusions: Three-dimensional speckle-tracking echocardiography-derived LV-RS and LV-LS are associated with the longitudinal shortening of the RV represented by TAPSE in healthy adults.

Cardiac structural, functional remodelling, and perfusion impairments across the spectrum of aortic stenosis

Abstract Background Aortic stenosis (AS) accounts for substantial global morbidity and premature mortality even in moderate AS (Mod-AS). Whilst myocardial remodeling response is considered critical in the adverse prognosis of Mod-AS, the precise mechanisms remain poorly understood. We aimed to prospectively assess myocardial remodeling, perfusion and energetics differences in Mod-AS and severe AS (Severe-AS). Methods Fifty-two Severe-AS and 25 Mod-AS patients and 18 demographically-matched controls underwent cardiovascular magnetic resonance and phosphorus-magnetic resonance spectroscopy to define left ventricular (LV) mass and function, global longitudinal shortening (GLS), rest and adenosine-stress myocardial blood flow (MBF), myocardial perfusion reserve (MPR), layer-specific perfusion metrics (subendocardial [Endo], subepicardial [Epi] MBF and MPR, and Endo-Epi-MBF ratio [Endo/Epi]), myocardial scar on late gadolinium enhancement (LGE) imaging, and myocardial energetics (phosphocreatine:ATP ratio [PCr/ATP]). Results Compared to controls, with increasing AS severity, there was progressive increase in LV concentricity (LV mass-index (controls: 46[40,51],Mod-AS:58[51,65],Severe-AS: 70[65,75]g/m2; P<0.0001), and stepwise decline in GLS (controls:19.9[17.6,22.2], Mod-AS:17.7[16.6,18.8], Severe-AS:13.4[12.5,14.4]%; P<0.0001) with significant differences between Mod-AS and Severe-AS in all three comparisons. Both stress MBF(controls:2.1[1.9,2.3],Mod-AS:1.9[1.6,2.2],Severe-AS:1.3[1.2,1.5]ml/min/g; P<0.0001) and MPR(controls:3.3[2.8,3.6],Mod-AS:2.8[2.4,3.2], Severe-AS:1.9[1.8,2.1]; P<0.0001) were only significantly reduced in Severe-AS compared to controls, with significant differences also detected between Mod-AS and Severe-AS. However, stress-endo-MBF (controls:2.0[1.8,2.3], Mod-AS:1.7[1.5,2.0], Severe-AS:1.2[1.1,1.3]ml/min/g; P<0.0001), stress-Endo/Epi(controls:1.00[0.93,1.07],Mod-AS:0.87[0.80,0.94],Severe-AS:0.81[0.75,0.82];P<0.0001), rest-Endo/Epi (controls:1.12[1.10,1.14], Mod-AS:1.06[1.03,1.09], Severe-AS:1.03[1.02,1.06]; P<0.0001) and endo-MPR (controls:3.2[2.7,3.6],Mod-AS:2.5[2.1,2.9],Severe-AS:1.7[1.5,1.8]; P<0.0001) were all significantly reduced in both Mod-AS and Severe-AS. Compared to controls, both AS groups showed significantly lower PCr/ATP (controls:2.2[2.0,2.3],Mod-AS:1.8[1.6,2.0],Severe-AS:1.7[1.6,1.8]; P<0.0001). Only the Severe-AS group had evidence of non-ischemic myocardial scarring on LGE (2.9[0.0,6.2]%), which was detected in 65%(n=34) of patients. AS severity (peak aortic valve velocity) correlated with stress-MBF (r=-0.45, P=0.0003), MPR (r=-0.44, P=0.0005) and GLS (r=-0.47, P=0.0001). Conclusions Moderate and severe-AS are both associated with cardiac concentric hypertrophy, reductions in myocardial energetics, and subendocardial hypoperfusion. Patients with Severe-AS exhibit a more pronounced phenotype with worse LV hypertrophy, contractile dysfunction and myocardial scarring compared to Mod-AS patients.

The impact of type 2 diabetes on short term myocardial morphological, functional, and energetic recovery post coronary artery bypass surgery in patients with ischemic heart disease

Abstract Background Type 2 diabetes (T2D) confers three times higher mortality in patients with ischemic heart disease (IHD). Moreover, amongst patients with IHD those with diabetes were shown to have higher long-term mortality from heart failure despite angiographic or surgical revascularisation with coronary artery bypass grafting (CABG). Impaired myocardial structural, functional, and energetic recovery may underpin this epidemiological observation. Consequently, using cardiovascular magnetic resonance and phosphorus-magnetic resonance spectroscopy scans, we aimed to assess the effect of T2D comorbidity on myocardial structural, functional, perfusion, and energetic recovery post-CABG in patients with IHD. Methods Seventy-seven IHD patients with (n=39) and without T2D (n=38) awaiting CABG were recruited. One-month pre- and 6-months post-CABG, cardiac phosphocreatine to ATP ratio (PCr/ATP), global longitudinal shortening (GLS) and 6-minute walk-distance (6MWD) were assessed in the study cohorts. The rest and adenosine-stress myocardial blood flow (MBF) assessments were only performed 6-months post-CABG. Results Pre-CABG, IHD-T2D patients had higher LV concentricity (LV mass to LV end diastolic volume ratio) (IHD-T2D:0.84[0.74,0.93],IHD-noT2D:0.72[0.67,0.77]g/mL,P=0.03]. worse PCr/ATP T2D (IHD-T2D:1.5[1.4,1.7],IHD-noT2D:1.8[1.6, 2.0];P=0.03) and shorter 6-minute walk distance (IHD-T2D:338[307,370],IHD-noT2D:399[364,434]m,P=0.007). There were no significant differences in LV volumes, ejection fraction or GLS between the two groups pre-CABG. Post-CABG, there was no longer a significant difference in cardiac energetics or 6-minute walk distances between the two groups due to a significant improvement in PCr/ATP in the IHD-T2D group. LV concentricity remained significantly elevated in the IHD-T2D group post CABG (IHD-T2D:0.82[0.75,0.88],IHD-noT2D:0.73[0.68,0.79]g/mL,P=0.04). Neither group showed a significant change in LVEF or GLS from the pre-CABG values, and post-CABG there were no differences in the rest or stress myocardial blood flows between the two groups. Conclusions Six months after CABG, neither IHD patients with T2D, nor IHD patients without T2D show any significant changes in LV structural remodelling or in contractile function. T2D does not jeopardise the short-term recovery in myocardial energetics or exercise distance post-CABG, with IHD patients with T2D showing more pronounced improvements post-CABG in both these assessments than patients without T2D. Larger longitudinal studies are needed to better understand the mechanisms of adverse longer-term cardiovascular outcomes suggested by epidemiological studies in IHD patients with T2D.

Myocardial remodelling in bicuspid aortic valve associated severe aortic stenosis and reverse remodelling after aortic valve replacement

Abstract Background Bicuspid aortic valve (BAV) is a common congenital heart disease and a major risk factor for aortic stenosis (AS). Myocardial remodelling response to AS plays an important prognostic role1. Cardiovascular magnetic resonance (CMR) can evaluate myocardial structure, function and perfusion in AS. Phosphorus magnetic resonance spectroscopy (31P-MRS) can also assess myocardial energetic consequences of AS2. Purpose Assess differences in myocardial remodelling between tricuspid aortic valve (TAV) and BAV-associated severe-AS, and their recovery 6 months post aortic valve replacement (AVR). Methods Eighty severe-AS patients (70[69-72]years) undergoing AVR (40 TAV, 40 BAV) and 21 demographically-matched controls were recruited. AS groups were matched for demographics, AS severity, surgical risk scores and comorbidities. One month before and 6 months post-AVR, patients underwent CMR and 31P-MRS for measuring left ventricular (LV) mass, concentricity-index (LV mass to LV end-diastolic volume ratio), global longitudinal shortening (GLS), rest and adenosine-stress myocardial blood flow (MBF), myocardial perfusion reserve (MPR) and energetics-index phosphocreatine to ATP ratio (PCr/ATP). Results Pre-AVR, there was no significant differences between the three cohorts when assessing LV ejection fraction, indexed LV end-diastolic volume and indexed end-systolic volume. Pre-AVR, both AS groups showed higher LV-concentricity (controls:0.53[0.51,0.60], TAV:0.95[0.82,1.07], BAV:0.92[0.82,1.08]g/ml;P<0.0001), higher mass-index (controls:45[39,50], TAV:73[67,78], BAV:74[68,80]g/m2;P<0.0001), impaired GLS (controls:18.8[16.5,19.5], TAV:12.6[11.3,13.9], BAV:13.6[10.9,16.6]%;P<0.0001). Reductions in both AS groups were also seen in PCr/ATP (controls:2.19[1.85,2.63], TAV:1.64[1.39,1.85], BAV:1.85[1.60,2.10];P=0.0004), stress-MBF (controls:2.16[1.88,2.27], TAV:1.35 [1.16,1.56], BAV:1.36[1.00,1.66]ml/min/g;P<0.0001), and MPR (controls:3.38[2.65,3.92], TAV:2.04 [1.78,2.46], BAV:1.83[1.58,2.78]ml/min/g;P<0.0001) against controls, with no significant differences between TAV and BAV. No significant difference was seen in the proportion of patients with TAV and BAV undergoing transcatheter or surgical AVR (table1). Post-AVR, the TAV and BAV groups experienced similar patterns of reverse LV-remodelling, with no significant differences in LV-concentricity (TAV:0.86[0.71,0.98], BAV:0.81[0.65,0.96];P=0.41), LV-mass-index (TAV:60[54,65], BAV:61[55,66];P=0.81), GLS (TAV 15.4[13.6,17.9], BAV 16.3[12.8,18.1];P=0.82. Perfusion and cardiac energetic improvements were also similar between the AS cohorts: PCr/ATP (TAV:1.96[1.68,2.26], BAV:1.96[1.79,2.13];P=0.91), stress-MBF (TAV:1.63[1.37,1.97], BAV:1.56[1.25,1.97];P=0.86), and MPR (TAV:2.64[1.91,3.26], BAV:2.55[2.07,3.28];P=0.70). Conclusions Patients with severe AS irrespective of BAV or TAV morphology, show a similar myocardial phenotype pre-AVR, with similar magnitudes of reverse remodelling post-AVR.

Inversion of Left Ventricular Axial Shortening: In Silico Proof of Concept for Treatment of HFpEF.

Left ventricular (LV) longitudinal function is mechanically coupled to the elasticity of the ascending aorta (AA). The pathophysiologic link between a stiff AA and reduced longitudinal strain and the subsequent deterioration in longitudinal LV systolic function is likely relevant in heart failure with preserved ejection fraction (HFpEF). The proposed therapeutic effect of freeing the LV apex and allowing for LV inverse longitudinal shortening was studied in silico utilizing the Living Left Heart Human Model (Dassault Systémes Simulia Corporation). LV function was evaluated in a model with (A) an elastic AA, (B) a stiff AA, and (C) a stiff AA with a free LV apex. The cardiac model simulation demonstrated that freeing the apex caused inverse LV longitudinal shortening that could abolish the deleterious mechanical effect of a stiff AA on LV function. A stiff AA and impairment of the LV longitudinal strain are common in patients with HFpEF. The hypothesis-generating model strongly suggests that freeing the apex and inverse longitudinal shortening may improve LV function in HFpEF patients with a stiff AA.

Right ventricular longitudinal shortening and right atrial volumes are not associated in healthy adults-detailed analysis from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study.

There is a close relationship between volumes of the right atrium (RA) and dimensions and derived functional sphincter-like features of the tricuspid annulus (TA). However, its relation to longitudinal TA motion is not clear, which can even be considered to be a characteristic of the longitudinal shortening of the right ventricle (RV) and represented by TA plane systolic excursion (TAPSE). Therefore, the aim of this cohort study was to perform a detailed analysis of the relationship of three-dimensional speckle-tracking echocardiography (3DSTE)-derived RA volumes and RV longitudinal shortening in healthy individuals. These parameters were also examined in case of average values and larger/smaller than mean values. The present study comprised 93 healthy adults (mean age: 27.7±6.3 years, 46 men), who participated in a complete medical investigation including two-dimensional, TAPSE, Doppler and 3DSTE-derived RA volumetric echocardiographic assessments. RA volumes, stroke volumes and emptying fractions were not related to TAPSE. In case of low, mean and high TAPSE, maximum [50.4±22.4 vs. 49.5±15.5 vs. 49.0±15.8 mL, P= not significant (ns)], preatrial contraction (36.9±16.8 vs. 34.5±10.4 vs. 35.6±10.5 mL, P= ns) and minimum (28.7±13.6 vs. 27.2±9.4 vs. 26.6±9.3 mL, P= ns) RA volumes did not differ. Higher RA volumes showed no associations with TAPSE either. 3DSTE-derived RA volumes and M-mode echocardiography-derived TAPSE representing RV longitudinal shortening are not associated in healthy adults. None of the RA volumes showed correlations with TAPSE.

Probing membrane deformation energy by KcsA potassium channel gating under varied membrane thickness and tension.

This study investigated how membrane thickness and tension modify the gating of KcsA potassium channels when simultaneously varied. The KcsA channel undergoes global conformational changes upon gating: expansion of the cross-sectional area and longitudinal shortening upon opening. Thus, membranes impose differential effects on the open and closed conformations, such as hydrophobic mismatches. Here, the single-channel open probability was recorded in the contact bubble bilayer, by which variable thickness membranes under a defined tension were applied. A fully open channel in thin membranes turned to sporadic openings in thick membranes, where the channel responded moderately to tension increase. Quantitative gating analysis prompted the hypothesis that tension augmented the membrane deformation energy when hydrophobic mismatch was enhanced in thick membranes.

The Stiffness of the Ascending Aorta Has a Direct Impact on Left Ventricular Function: An In Silico Model.

During systole, longitudinal shortening of the left ventricle (LV) displaces the aortic root toward the apex of the heart and stretches the ascending aorta (AA). An in silico study (Living Left Heart Human Model, Dassault Systèmes Simulia Corporation) demonstrated that stiffening of the AA affects myocardial stress and LV strain patterns. With AA stiffening, myofiber stress increased overall in the LV, with particularly high-stress areas at the septum. The most pronounced reduction in strain was noted along the septal longitudinal region. The pressure-volume loops showed that AA stiffening caused a deterioration in LV function, with increased end-systolic volume, reduced systolic LV pressure, decreased stroke volume and effective stroke work, but elevated end-diastolic pressure. An increase in myofiber contractility indicated that stroke volume and effective stroke work could be recovered, with an increase in LV end-systolic pressure and a decrease in end-diastolic pressure. Longitudinal and radial strains remained reduced, but circumferential strains increased over baseline, compensating for lost longitudinal LV function. Myofiber stress increased overall, with the most dramatic increase in the septal region and the LV apex. We demonstrate a direct mechanical pathophysiologic link between stiff AA and reduced longitudinal left ventricular strain which are common in patients with HFpEF.

Early Alteration of Right Ventricle-Pulmonary Artery Coupling in Experimental Heart Failure With Preserved Ejection Fraction.

Pulmonary hypertension and right ventricular (RV) dysfunction are major prognostic determinants in patients with heart failure with preserved ejection fraction (HFpEF). The underlying pathomechanisms remain unknown. In this context, we sought to study the pathogenesis of pulmonary hypertension and RV dysfunction in a rat model of obesity-associated HFpEF. HFpEF was induced in obesity-prone rats fed a high-fat diet (n=13) and compared with obesity-resistant rats fed with standard chow (n=9). After 12 months, the animals underwent echocardiographic and hemodynamic evaluation followed by tissue sampling for pathobiological assessment. HFpEF rats presented mild RV pressure overload (with increased RV systolic pressure and pulmonary vascular resistance). No changes in pulmonary artery medial thickness and exvivo vasoreactivity (to acetylcholine and endothelin-1) were observed and RNA sequencing analysis failed to identify gene clustering in HFpEF lungs. However, released nitric oxide levels were decreased in HFpEF pulmonary artery, while lung expression of preproendothelin-1 was increased. In HFpEF rats, RV structure and function were altered, with RV enlargement, decreased RV fractional area change and free wall longitudinal fractional shortening, together with altered right ventricle-pulmonary artery coupling (estimated by tricuspid annular plane systolic excursion/systolic pulmonary artery pressure). Hypertrophy and apoptosis (evaluated by transferase biotin- dUTP nick-end labeling staining) were increased in right and left ventricles of HFpEF rats. There was an inverse correlation between tricuspid annular plane systolic excursion/systolic pulmonary artery pressure and RV apoptotic rate. Plasma levels of soluble suppression of tumorigenicity-2, interleukin-1β, -6 and -17A were increased in HFpEF rats. Obesity-associated HFpEF in rats spontaneously evolves to pulmonary hypertension-HFpEF associated with impaired right ventricle-pulmonary artery coupling that appears disproportionate to a slight increase in RV afterload.

Right Ventricular Structure and Function in Adolescent Athletes: A 3D Echocardiographic Study.

The aim of this study was to characterize the right ventricular (RV) contraction pattern and its associations with exercise capacity in a large cohort of adolescent athletes using resting three-dimensional echocardiography (3DE). We enrolled 215 adolescent athletes (16±1 years, 169 males, 12±6 hours of training/week) and compared them to 38 age and sex-matched healthy, sedentary adolescents. We measured the 3DE-derived biventricular ejection fractions (EF). We also determined the relative contributions of longitudinal EF (LEF/RVEF) and radial EF (REF/RVEF) to the RVEF. Same-day cardiopulmonary exercise testing was performed to calculate VO2/kg. Both LV and RVEFs were significantly lower (athletes vs. controls; LVEF: 57±4 vs 61±3, RVEF: 55±5 vs 60±5%, p<0.001). Interestingly, while the relative contribution of radial shortening to the global RV EF was also reduced (REF/RVEF: 0.40±0.10 vs 0.49±0.06, p<0.001), the contribution of the longitudinal contraction was significantly higher in athletes (LEF/RVEF: 0.45±0.08 vs 0.40±0.07, p<0.01). The supernormal longitudinal shortening correlated weakly with a higher VO2/kg (r=0.138, P=0.044). Similarly to the adult athlete's heart, the cardiac adaptation of adolescent athletes comprises higher biventricular volumes and lower resting functional measures with supernormal RV longitudinal shortening. Characteristic exercise-induced structural and functional cardiac changes are already present in adolescence.

Feasibility Value of Right Ventricular Longitudinal Shortening Fraction and the Prognostic Implications in Patients With Heart Transplantation.

Right ventricular longitudinal shortening fraction (RVLSF) is a 2-dimensional speckle tracking echocardiography parameter based on tricuspid annular displacement analysis that could be used to assess right ventricular (RV) systolic function. The value of RVLSF in the assessment of RV systolic function in recipients of heart transplantation (HT) and whether RVLSF can replace strain parameters remains unknown. A total of 153 adult patients who underwent HT were consecutively enrolled in this prospective longitudinal study. All subjects were examined by conventional transthoracic 2-dimensional echocardiography and 2-dimensional speckle tracking echocardiography to evaluate the RV end-diastolic basal diameter, RV end-diastolic area, fractional area change, peak systolic velocity of tricuspid annulus, tricuspid annular plane systolic excursion, RV free wall strain, and RVLSF. Cox proportional hazards regression was used to test if the parameters of interest had independent prognostic value for adverse outcome prediction in patients who underwent HT. A significant positive correlation was found between the measurements of RVLSF and RV free wall strain (r=0.927, P<0.001). Compared with the event-free group, the adverse outcome group displayed reduced RVLSF and RV free wall strain and higher age (P<0.001, <0.001, =0.016, respectively) in patients who underwent HT. RVLSF and RV free wall strain were independently associated with poor prognosis in multivariable analysis (both P<0.001). RVLSF assessment provides an effective evaluation of RV longitudinal systolic function in the transplanted hearts and has prognostic value for adverse outcomes in patients undergoing HT.

Prognostic Value of a New Right Ventricular-to-Pulmonary Artery Coupling Parameter Using Right Ventricular Longitudinal Shortening Fraction in Patients Undergoing Transcatheter Aortic Valve Replacement: A Prospective Echocardiography Study.

Introduction: Right-ventricular-to-pulmonary artery (RV-PA) coupling, measured as the ratio of tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP), has emerged as a predictor factor in patients undergoing transcatheter aortic valvular replacement (TAVR). Right ventricular longitudinal shortening fraction (RV-LSF) outperformed TAPSE as a prognostic parameter in several diseases. We aimed to compare the prognostic ability of two RV-PA coupling parameters (TAPSE/PASP and the RV-LSF/PASP ratio) in identifying MACE occurrences. Method: A prospective and single-center study involving 197 patients who underwent TAVR was conducted. MACE (heart failure, myocardial infarction, stroke, and death within six months) constituted the primary outcome. ROC curve analysis determined cutoff values for RV-PA ratios. Multivariable Cox regression analysis explored the association between RV-PA ratios and MACE. Results: Forty-six patients (23%) experienced the primary outcome. No significant difference in ROC curve analysis was found (RV-LSF/PASP with AUC = 0.67, 95%CI = [0.58-0.77] vs. TAPSE/PASP with AUC = 0.62, 95%CI = [0.49-0.69]; p = 0.16). RV-LSF/PASP < 0.30%.mmHg-1 was independently associated with the primary outcome. The 6-month cumulative risk of MACE was 59% (95%CI = [38-74]) for patients with RV-LSF/PASP < 0.30%.mmHg-1 and 17% (95%CI = [12-23]) for those with RV-LSF/PASP ≥ 0.30%.mmHg-1; (p < 0.0001). Conclusions: In a contemporary cohort of patients undergoing TAVR, RV-PA uncoupling defined by an RV-LSF/PASP < 0.30%.mmHg-1 was associated with MACE at 6 months.

Right Ventricular Longitudinal Shortening is not Associated with Left Ventricular Rotational Mechanics in Healthy Adults - Insights from the Three-dimensional Speckle-tracking Echocardiographic MAGYAR-Healthy Study.

The left ventricle (LV) not only contracts, but its rotational mechanics have a significant role in systolic ejection, whereas the right ventricle (RV) is substantially different in shape and function, and its contractility is not accompanied by rotational features. Simple M-mode echocardiography-based tricuspid annular plane systolic excursion (TAPSE) reflects RV longitudinal contraction or shortening. The aim of the present study was to examine the relationship between the parameters characterizing the rotational mechanics of the LV as assessed by three-dimensional speckle-tracking echocardiography (3DSTE) and the TAPSE. The effects of different degrees of these parameters on each other were also examined. The present retrospective analysis evaluated the results of 80 healthy adult individuals with an average age of 28.1 6.3 years (33 males) with LV rotational mechanics being directed normally. All cases have undergone complete two-dimensional Doppler echocardiography with the measurement of TAPSE and 3DSTE. None of the LV volumes and rotational parameters showed any differences in healthy cases with TAPSE 18-21 mm vs. TAPSE 22 mm. Similarly, right atrial (RA) volumetric parameters did not differ either. TAPSE showed no associations with the degree of basal LV rotation. RA volumes were slightly increased with higher basal LV rotation. Similar to basal LV rotation, TAPSE did not change with the degree of apical LV rotation and a tendentious increase of RA volumes could be demonstrated with increasing apical LV rotation. No correlation could be demonstrated between apical and basal LV rotations and TAPSE. 3DSTE-derived LV rotational parameters and TAPSE are not associated suggesting that LV twist is independent of RV longitudinal shortening in healthy circumstances.

Association between left ventricular systolic function parameters and myocardial injury, organ failure and mortality in patients with septic shock

BackgroundLeft ventricular ejection fraction (LVEF) is inconsistently associated with poor outcomes in patients with sepsis. Newer parameters such as LV longitudinal strain (LVLS), mitral annular plane systolic excursion (MAPSE) and LV longitudinal wall fractional shortening (LV-LWFS) may be more sensitive indicators of LV dysfunction, but are sparsely investigated. Our objective was to evaluate the association between five traditional and novel echocardiographic parameters of LV systolic function (LVEF, peak tissue Doppler velocity at the mitral valve (s´), LVLS, MAPSE and LV-LWFS) and outcomes in patients admitted to the Intensive Care Unit (ICU) with septic shock.MethodsA total of 152 patients admitted to the ICU with septic shock from two data repositories were included. Transthoracic echocardiograms were performed within 24 h of ICU admission. The primary outcome was myocardial injury, defined as high-sensitivity troponin T ≥ 45 ng/L on ICU admission. Secondary outcomes were organ support-free days (OSFD) and 30-day mortality. We also tested for the prognostic value of the systolic function parameters using multivariable analysis.ResultsLVLS, MAPSE and LV-LWFS, but not LVEF and s´, differed between patients with and without myocardial injury. After adjustment for age, pre-existing cardiac disease, Simplified Acute Physiology (SAPS3) score, Sequential Organ Failure Assessment (SOFA) score, plasma creatinine and presence of right ventricular dysfunction, only MAPSE and LV-LWFS were independently associated with myocardial injury. None of the systolic function parameters were associated with OSFD or 30-day mortality.ConclusionsMAPSE and LV-LWFS are independently associated with myocardial injury and outperform LVEF, s´ and LVLS. Whether these parameters are associated with clinical outcomes such as the need for organ support and short-term mortality is still unclear.Trial registration NCT01747187 and NCT04695119.

Unsupervised unpaired multiple fusion adaptation aided with self-attention generative adversarial network for scar tissues segmentation framework

Late gadolinium enhancement (LGE) is a specialized imaging technique used in cardiovascular magnetic resonance (CMR) imaging to detect and characterize areas of scar tissue or fibrosis within the heart muscle. After a heart attack, the affected region of the heart muscle becomes scarred due to insufficient blood supply. LGE CMR enhances the infarcted myocardium to appear with distinctive brightness compared to healthy tissues. It is primarily used to assess various heart conditions and can identify the extent and location of scar tissue, helping in risk stratification and guiding treatment decisions. Automated myocardium segmentation in LGE CMR poses challenges due to intensity heterogeneity caused by the accumulation of contrast agents in infarcted areas. Furthermore, LGE CMR images with gold standard labels are particularly scarce compared to other sequences, making the task even more demanding. Besides, the heart’s motion involves complex non-rigid deformations, including regional wall thickening, circumferential, and longitudinal ventricular shortening, making it challenging to model. This work presents an unsupervised unpaired domain adaptive scar tissue segmentation framework aided with the self-attention generative adversarial network. Besides, we proposed a novel segmentation architecture based on a parallel transformer for scar segmentation and compared the results with and without style transfer GAN and unpaired style self-supervised attention GAN. Besides, to model longitudinal changes in scare, we used eight days’ time points as a source and 1 month and 12 as a target and applied our proposed attention-generative network to transfer style from one-time point to another time. Experiments on four different LGE MICCAI datasets from 2019 to 2023 achieved significantly better performance than state-of-the-art segmentation methods.

Improvement in myocardial energetics and perfusion with Liraglutide in patients with type 2 diabetes- A randomised, single centre, open label, cross-over drug trial

Abstract Background Both the insulin secretion and insulin resistance in Type 2 diabetes (T2D) are amenable to pharmacological intervention. In a single center, open-label, randomized, cross-over design trial we sought to compare two distinct glycaemic control strategies of targeting beta-cell dysfunction and promoting insulin secretion using Glucagon-like peptide-1 receptor agonists (GLP-1RA) -liraglutide and targeting peripheral insulin resistance using a peroxisome proliferator activated receptor-gamma agonist (PPAR-g)-pioglitazone to see which results in greater improvements in myocardial perfusion, energetics and function in patients with T2D. Methods Fifty-two T2D patients were screened. Eligible patients with no known prior cardiovascular disease were randomized in a 1:1 ratio to be administered one of the study drugs for a 16-week treatment period followed by an 8-week washout and a further 16-week treatment period for the second drug. Thirty-three eligible participants completed both treatment periods. Participants have undergone 31phosphorus magnetic resonance spectroscopy (31P-MRS) at rest and dobutamine stress followed by the cardiac magnetic resonance (CMR) scans. The CMR protocol consisted of rest and dobutamine stress cine imaging, perfusion imaging (motion corrected, automated in-line perfusion mapping), velocity-encoded mitral in-flow imaging and late gadolinium enhanced imaging at 3T immediately before commencement and after completion of each treatment arm (four scans per participant). Results Clinical and biochemical characteristics, and CMR/31P-MRS results are provided in Tables 1&amp;2 respectively. Liraglutide therapy resulted in a significant reductions in the body mass index and significant improvements in glycemic control. Both drugs reduced insulin resistance indicated by a reduction in the mean triglyceride index. There were no significant changes in NTproBNP or troponin levels with either drug. Therapy with either drug did not result in a significant change in the LV end-diastolic volume, ejection fraction or global longitudinal shortening. Pioglitazone led to a significant increment in mean LV mass and LV mass index, while no significant effect in myocardial mass or mass index were detected with liraglutide. Liraglutide therapy resulted in increased rest and dobutamine stress energetics, global stress myocardial blood flow and myocardial perfusion reserve index. While pioglitazone treatment showed no significant effect in these parameters, an isolated improvement in the rest diastolic function was detected in this arm. Conclusions In this randomised cross-over design trial we showed for the first time that four months treatment with glucagon like protein 1 receptor agonist liraglutide results in significant improvements in myocardial stress perfusion and energetics. Pioglitazone results in an isolated improvement in rest diastolic funct

Maternal myocardial recovery twelve months post-partum in women with pregnancies complicated by gestational diabetes or preeclampsia - single center, longitudinal cohort study

Abstract Background Gestational diabetes mellitus (GDM) and preeclampsia (PE) are the leading obstetric complications of pregnancy. Both are associated with a substantial increase in the risk of long-term cardiovascular disease. However, pregnant women are underrepresented in clinical research and the mechanisms of long-term cardiovascular complications in women with obstetric complications remain to be elucidated. Objectives This longitudinal cohort study was designed to assess maternal cardiac alterations during the third trimester of pregnancy and their recovery twelve-months post-partum in women with GDM (n=30) or preeclampsia (n=24) compared to women with healthy pregnancies (HP)(n=38). Methods 31P-MRS and CMR were used to define PCr/ATP, tissue characteristics, left ventricular (LV) volumes, mass, EF, global longitudinal shortening (GLS), and mitral in-flow E/A ratio. Investigations were repeated 12-months postpartum. With obesity as a common risk factor for both GDM and PE, 10 overweight and 10 normal-weight nulliparous women served as non-pregnant controls. Results Participants were matched for age and ethnicity(Table-1). Both the GDM and PE groups had higher BMI compared to the HP. Compared to the HP group, women with GDM had higher LV mass (90[85,94] vs 103[96,112]g; p=0.001) and lower myocardial PCr/ATP (2.2[2.1,2.4] vs 1.9[1.7,2]; p&amp;lt;0.0001), LV end-diastolic volumes (EDV)(76[72,80] vs 67[63,71]ml, p=0.03) and GLS (20[18,21] vs 18[17,19]%; p=0.008). Compared to the HP group, at similar magnitudes to women with GDM, the women with PE exhibited higher LV mass (90[85,94] vs 118[111,125]g; p&amp;lt;0.0001) and lower myocardial PCr/ATP (2.2[2.1,2.4] vs 1.9[1.8,2.1]; p=0.0004) and GLS (20[18,21] vs 16[14,17]%; p=0.01). There were no significant differences in PCr/ATP, LV EDV, mass or GLS between the GDM and PE groups. Twelve-months postpartum there were no significant changes in any of the cardiac assessments in women in the HP, GDM or PE groups compared to their respective third-trimester pregnancy assessments (Figure-1). Compared to nulliparous normal-weight controls, HP was associated with no significant differences in myocardial PCR/ATP, LV volumes, mass, EF or GLS. The overweight nulliparous controls showed significantly higher LV mass and lower myocardial PCr/ATP and GLS than normal-weight controls. There were no significant differences in LV mass, PCr/ATP or GLS between the overweight nulliparous controls and GDM or PE groups during or after pregnancy. Conclusions Despite distinct aetiologies women with GDM and PE exhibit a similar myocardial phenotype during and after pregnancy with persistent subtle abnormalities in myocardial PCr/ATP ratio, LV mass and GLS compared to women with HP during pregnancy and twelve months’ postpartum assessments. Women with GDM and PE show similar myocardial alterations to nulliparous women with obesity, suggesting that the myocardial changes are predominantly driven by obesity-associated metabolic dysfunction.

Prognostic Value of Right Ventricular Longitudinal Shortening Fraction in Patients With ST-Elevation Myocardial Infarction: A Prospective Echocardiography Study

Background: Right ventricular systolic dysfunction (RVsD) frequently occurs in patients with ST-elevation myocardial infarction (STEMI). However, the diagnosis depends on the echocardiographic parameters to define RVsD. Right ventricle longitudinal shortening fraction (RV-LSF) is an accurate and reproducible two-dimensional speckle tracking parameter associated with clinical events in various pathologies.Objective: The aim of the study is to evaluate the association between RVsD and major adverse cardiovascular events (MACE) occurrence in a cohort of STEMI patients.Methods: Adult STEMI patients admitted to Amiens University Hospital's cardiovascular intensive care unit between May 2021 and November 2022, who underwent coronary angiography and TTE within 48 hours of admission, were included. RVsD was defined as RV-LSF < 20%. The primary outcome was MACE occurrence, including heart failure, myocardial infarction, stroke, and death within six months of admission. Multivariable Cox regression analysis with proportional hazard ratio (HR) models assessed the association between RVsD and MACE.Results: Among the 164 included patients, 72 (44%) had RVsD, and 92 (56%) did not. The RVsD group had a significantly higher proportion of MACE during the six-month follow-up (n = 23/72, 33%) than the no-RVsD group (n = 8/92, 9%; P = 0.001). RVsD showed an independent association with MACE at six months (HR=3.1, 95% CI [1.35-7.30], P=0.008). Left ventricular ejection fraction < 40 % and TIMI score > 4 were independently associated with RVsD (odds ratio = 2.80, 95% CI [1.34-5.98] and OR=2.15, 95% CI [1.18-4.39 respectively]; P = 0.015). The cumulative risk of MACE at six months was 33% for RV-LSF < 20% and 9% for RV-LSF ≥ 20% (log-rank test P < 0.001).Conclusion: RVsD, defined by RV-LSF < 20%, is associated with an increased risk of MACE after STEMI.

Load sharing between synergistic muscles characterized by a ligand-binding approach and elastography

The skeletal muscle contraction is determined by cross-bridge formation between the myosin heads and the actin active sites. When the muscle contracts, it shortens, increasing its longitudinal shear elastic modulus ({mu }_{L}). Structurally, skeletal muscle can be considered analogous to the molecular receptors that form receptor–ligand complexes and exhibit specific ligand-binding dynamics. In this context, this work aims to apply elastography and the ligand-binding framework to approach the possible intrinsic mechanisms behind muscle synergism. Based on the short-range stiffness principle and the acoustic–elasticity theory, we define the coefficient C, which is directly related to the fraction saturation of molecular receptors and links the relative longitudinal deformation of the muscle to its {mu }_{L}. We show that such a coefficient can be obtained directly from {mu }_{L} estimates, thus calculating it for the biceps brachii, brachioradialis, and brachialis muscles during isometric elbow flexion torque (τ) ramps. The resulting Cleft(tau right) curves were analyzed by conventional characterization methods of receptor–ligand systems to study the dynamical behavior of each muscle. The results showed that, depending on muscle, Cleft(tau right) exhibits typical ligand-binding dynamics during joint torque production. Therefore, the above indicates that these different behaviors describe the longitudinal shortening pattern of each muscle during load sharing. As a plausible interpretation, we suggested that this could be related to the binding kinetics of the cross-bridges during their synergistic action as torque increases. Likewise, it shows that elastography could be useful to assess contractile processes at different scales related to the change in the mechanical properties of skeletal muscle.

Three-dimensional echocardiographic evaluation of longitudinal and non-longitudinal components of right ventricular contraction: results from the World Alliance of Societies of Echocardiography study.

Right ventricular (RV) functional assessment is mainly limited to its longitudinal contraction. Dedicated three-dimensional echocardiography (3DE) software enabled the separate assessment of the non-longitudinal components of RV ejection fraction (EF). The aims of this study were (i) to establish normal values for RV 3D-derived longitudinal, radial, and anteroposterior EF (LEF, REF, and AEF, respectively) and their relative contributions to global RVEF, (ii) to calculate 3D RV strain normal values, and (iii) to determine sex-, age-, and race-related differences in these parameters in a large group of normal subjects (WASE study). 3DE RV wide-angle datasets from 1043 prospectively enrolled healthy adult subjects were analysed to generate a 3D mesh model of the RV cavity (TomTec). Dedicated software (ReVISION) was used to analyse RV motion along the three main anatomical planes. The EF values corresponding to each plane were identified as LEF, REF, and AEF. Relative contributions were determined by dividing each EF component by the global RVEF. RV strain analysis included longitudinal, circumferential, and global area strains (GLS, GCS, and GAS, respectively). Results were categorized by sex, age (18-40, 41-65, and >65 years), and race. Absolute REF, AEF, LEF, and global RVEF were higher in women than in men (P < 0.001). With aging, both sexes exhibited a decline in all components of longitudinal shortening (P < 0.001), which was partially compensated in elderly women by an increase in radial contraction. Black subjects showed lower RVEF and GAS values compared with white and Asian subjects of the same sex (P < 0.001), and black men showed significantly higher RV radial but lower longitudinal contributions to global RVEF compared with Asian and white men. 3DE evaluation of the non-longitudinal components of RV contraction provides additional information regarding RV physiology, including sex-, age-, and race-related differences in RV contraction patterns that may prove useful in disease states involving the right ventricle.