Radial Strain Research Articles

Impaired strain in diabetic patients with stable coronary artery disease assessed by cardiac magnetic resonance

Abstract Background Type 2 diabetes mellitus (T2DM) can contribute or lead to myocardial structural derangement by multiple mechanisms, including ischemic cardiomyopathy and, more rarely and of difficult evaluation, diabetic cardiomyopathy. Early stages of myocardial dysfunction can be assessed by strain analysis with cardiac magnetic resonance feature tracking (CMR-FT), however, there is no studies that examined deformation parameters in diabetic patients with stablished coronary artery disease (CAD). Purpose We sought to compare the strain parameters of patients with and without T2DM with stable CAD. Methods Patients with stable multivessel CAD and preserved left ventricular ejection fraction (LVEF), included in the MASS V trial, underwent contrast-enhanced cardiac magnetic resonance before revascularization procedures. Patients were stratified according to T2DM diagnosis at baseline. Feature tracking was performed using short-axis cine images and 2- and 4-chamber long-axis images. The left ventricular endocardial and epicardial contours of the end diastole phase were manually delineated in all images. Automatically tracking contours were performed to calculate left ventricular global longitudinal (LVGLS), circumferential (LVGCS) and radial (LVGRS) strain (FIGURE 1). Results Of 202 patients studied, 88 (44%) were diabetic and 114 (56%) non-diabetic. Baseline characteristics were similar between groups (age 70 ± 10 vs 69 ± 11; 69% vs 68% males; LVEF 65 ± 13 vs 67 ± 9). Mean Syntax score was 21.2 ± 8.5 vs 20.4 ± 8.5 (P=0.52) in diabetic and non-diabetic, respectively. There were no differences in left ventricle volumes, mass and LVEF. Mean LGE mass was 2.3 ± 0.9 vs 1.9 ± 0.9 grams (P=0.32) respectively in T2DM and control groups. Strain values were all reduced in T2DM patients, as shown in FIGURE 2 (LVGLS: -15.5% ± 2.3% vs -17.5% ± 2.7%, P=0.02; LVGCS: -15.4% ± 2.6% vs -17.4% ± 3.0%, P=0.03; LVGCS: 25.9% ± 5.9% vs 29.5% ± 7.2%, P=0.01). Multivariable analyses adjusted for age, sex, BMI, hypertension, Syntax score and LGE mass showed no differences in the results. Conclusion In this study, T2DM was associated with impaired deformation parameters (decreased left ventricular global longitudinal, circumferential, and radial strain). These findings suggest myocardial dysfunction in diabetic patients when compared to control subjects in the setting of stable multivessel CAD.FIGURE 1FIGURE 2

Three-dimensional deformation imaging to detect myocardial scar

Abstract Introduction Myocardial scar or fibrosis has significant implications in patient management and prognosis. Currently, cardiovascular magnetic resonance (CMR) is the reference technique for detection and quantification of scar though other imaging modalities have been proven to be useful as well. Purpose This study aims to investigate the usefulness of 3D strain echocardiography to identify myocardial scar in patients with ischaemic and non-ischaemic myocardial fibrosis using late gadolinium enhancement (LGE) CMR as a reference. Methods 149 individuals with ischaemic (89), non-ischaemic scar (26) and no scar (34) on LGE CMR underwent 3D transthoracic echocardiography. The 3D data sets were processed with the 4D LV analysis tool by TOMTEC Imaging Systems GmbH, Germany. The longitudinal, circumferential, radial, and principal tangential strain were calculated. Using a 16 LV-segment model the areas of LGE were assessed on CMR images, and a correlation between 3D strain values and LGE was investigated. Results A multivariate binary logistic regression model was built with the conditional backward elimination method using LGE as the dependent variable. The predictors made a significant contribution to the model (Wald test: 49.985, p<0.001). The Cox & Snell R-square was 0.141, and Nagelkerke R-square was 0.232, suggesting that the final model explains 14.1% or 23.2% of LGE variability. By logistic regression analysis, less negative peak principal tangential strain (P-PTS), peak circumferential strain (P-SC), and end-systolic circumferential strain (ES-CS) increased the odds, whereas increased peak radial strain (P-RS) decreased the likelihood of LGE (Table 1). The LGE extent was calculated as the average LGE transmurality of all 16 segments and was used as the dependent variable in linear regression models. The LGE extent was significantly correlated with all strain indices (Table 2). By stepwise linear regression analysis, P-PTS (B=0.029, 95%CI:0.019-0.040, P<0.001) outperformed the remaining strain variables in terms of linear association with LGE extent. Association between strain indices and the presence or absence of myocardial fibrosis in each of the 16 segments was tested by point biserial correlation (Table 3). PTS and CS indices were associated with myocardial fibrosis in 10/16 segments; RS indices were associated with LGE in 9/16 segments, and LS was not related to the presence of LGE in 15/16 segments. Septal (basal-mid-apical) and mid/apical anterior and inferior segmental strain showed more consistent associations with corresponding myocardial fibrosis. Conclusion 3D strain echocardiography is a promising and easily accessible technique, that can be used to identify areas of myocardial scar as it correlates well with LGE in many LV segments. Echocardiography is a bedside and widely available technique, and it could be used in patients with contraindications or no access to CMR or myocardial perfusion scan.Table 3

Prognostic value of multiparametric cardiac magnetic resonance after revascularized STEMI

Abstract Despite early revascularization of STEMI through angioplasty, the prognosis following STEMI remains poor for a non-negligible percentage of patients (1). In this setting, multiple imaging parameters have demonstrated their prognostic value. The aim of the present study is to evaluate which of these parameters are the most potent predictors of events following revascularized STEMI. Methods A prospective observational study was conducted, including a cohort of revascularized STEMI patients and who underwent cardiac MRI during the first week. The protocol included cardiac functional analysis and with b-SSFP sequences for evaluation of volumes, mass, ejection fraction and also circumferential and radial strain with feature tracking. STIR sequences were used to assess edema and salvaged myocardium, IR-FGE sequences were employed for evaluation of necrosis size and microvascular obstruction. Intra-infarct hemorrhage assessment was performed using T2* mapping sequences as previosly described (2,3,4) . A semi-automatic analysis was conducted, considering as microvascular obstruction segments with hypointensity in the infarct core and as segments with hemorrhage those with a T2* less than 20 ms. The association of imaging parameters with cardiovascular events in the first year following STEMI was studied using ROC curves. Variables with significant association were analyzed using a multivariate logistic regression model. Results Ninety-four patients with a mean age of 63 (SD 13) years were included. Nine of them had cardiovascular events in the first year and two of them died. The relative extent of necrosis and microvascular obstruction, minimal radial strain, left ventricular ejection fraction (LVEF) and indexed left ventricular end- systolic volume (ILVESV) showed significant association with cardiovascular events after STEMI. Variables with significant association were entered into a multivariate predictive model, revealing that the extent of microvascular obstruction (OR: 1.9, p=0.02) and the left ventricular end-systolic volume (OR: 1.04, p<0.01) are the only independent predictors of cardiovascular events following STEMI. Conclusion Although multiple imaging parameters have shown prognostic value after STEMI, the ILVESV and the extent of microvascular obstruction are the only independent predictors of events following STEMI.Multiparametric cardiac MR in STEMIAREA UNDER ROC CURVE OF CMR PARAMETERS

Cardiac contractility index, a novel biomarker of incident heart failure amongst people with normal left ventricular ejection fraction in the UK Biobank

Abstract Background Cardiac contractility index (CCI) is a simple non-invasive measure of myocardial contractility defined by systolic blood pressure divided by indexed left ventricular end-systolic volume. Although left ventricular ejection fraction (LVEF) is essential for phenotyping patients with suspected heart failure (HF), it is load dependent and insensitive to subtle subclinical ventricular dysfunction. Left ventricular (LV) strain, although more sensitive at detecting subtle disturbances in myocardial function, also does not reflect loading conditions and dependency on image quality and inter-vendor variability limit widespread use. The ability of CCI to identify patients with subclinical left ventricular dysfunction at risk of developing HF is unknown. Purpose We aimed to: 1) explore the relationship between CCI with conventional imaging biomarkers of LV systolic dysfunction and 2) assess whether CCI could identify those at increased risk of incident HF in people without pre-existing left ventricular dysfunction in the UK Biobank imaging study. Methods We explored the relationship between CCI and laboratory and imaging biomarkers of systolic function, including LVEF and LV strain. Scatter plots were constructed for CCI with LVEF and LV strain. Pearson’s coefficients (r) and coefficient of determination (r2) were calculated to assess for correlations. People with sex-specific thresholds of abnormally low LVEF derived from within the same cohort (<48% for men, and <51% for women) were then excluded. CCI was then dichotomised as being high or low based its median value (4.4 mmHg/ml/m2). Age-sex adjusted Cox proportional hazards ratios (HR) with 95% CIs were estimated for the primary outcome of incident HF (derived from linked national digital registries) in addition to modelling with restricted cubic splines. Results We included 38,215 people (median age 55 years, 48% men). There was moderate correlation between CCI with LVEF (r=0.53 [0.53-0.54], R2=0.29; p<0.001), LV global circumferential strain (r=-0.50 [-0.50- -0.49], R2=0.25; p<0.001) and radial strain (r=-0.49 [0.48-0.50], R2=0.24; p<0.001), although was only weekly correlated with LV global longitudinal strain (r=-0.19 [-0.20- -0.18], R2=0.03; p<0.001) (Figure 1A). Using sex-specific thresholds 33,739 (88.3%) had a normal LVEF. During 195,584 person-years of follow-up (median 5.5 years), a total of 221 (0.7%) participants developed HF. Age-sex adjusted low CCI at baseline was associated with an increased risk of incident HF (adjusted HR 1.33 [1.01-1.75]; p=0.043). The association between CCI and incident HF was curvilinear (Figure 1B). Conclusions CCI identifies people with subclinical left ventricular systolic dysfunction at risk of developing incident heart failure.

Left ventricular myocardial work predicts clinical course in patients with heart failure with mildly reduced ejection fraction

Abstract Heart failure with mildly reduced ejection fraction (HFmrEF) often represents a movable patients subset that changes its HF category by increasing or reducing EF. Course prediction is challenging due to insufficient evidence to date. We studied multiple newly established parameters in order to find predictors of clinical course of HFmrEF. Methods 135 patients (61 women) 62±5 years with HFmrEF NYHA II-III on GDMT were enrolled. Longitudinal (GLS), circumferential (GCS) and radial strain (GRS), peak LV twist (LVTR) were measured by speckle tracking from apical and short axis views. Left ventricular (LV) global myocardial work (GW) index (GWI) was obtained from pressure-strain loops derived from LV GLS and supine systemic blood pressure measured right before the image acquisition. Then constructive GW (GCW) as the sum of positive work due to myocardial shortening during systole and negative work due to lengthening during isovolumic relaxation, wasted GW (GWW) as energy loss by myocardial lengthening in systole and shortening in isovolumic relaxation and GW efficiency (GWE) as the percentage ratio of constructive work to the sum of constructive work and wasted work were obtained by dedicated software. All parameters were analyzed offline by one experienced specialist. Patients were followed up for 1 year. Results 38 (28%) patients improved EF to the value ≥50%, 31 (23%) reduced EF to ≤40%. Patients with improved EF had significantly higher absolute values of GLS (17.3±2.2 vs 15.8±3.1%, p<0.03), GCS (18.9±2.6 vs 16.1±1.9%, p<0.02), GRS (42.5±7.2% vs 31.3±4.7%, p<0.02), LVT (6.2±2.5° vs 5.3±2.3°, p<0.03), GCW (2253±121 vs 1872±132 mmHg%, p<0.001) and lower GWW (108±7 vs 128±12 mmHg%) compared with patients with later reduced EF. Multivariate analysis showed that lower GCW was associated with EF reduction (HR 0.982, 95% CI 0.969–0.996, p = 0.012). GCW was the powerful predictor of CV events (AUC 0.94) with cut off value of 1495 mmHg% that had 98% sensitivity and 86% specificity. Conclusion LV GCW predicts EF changes in patients with HFmrEF.

Additive effect of metabolic dysfunction-associated fatty liver disease on left ventricular function and global strain in type 2 diabetes mellitus patients: a 3.0 T CMR feature tracking study

Abstract Purpose Type 2 diabetes mellitus (T2DM) represents the most prevalent form of diabetes, exerting a significant influence on cardiovascular health. Concurrently, metabolic dysfunction-associated fatty liver disease (MAFLD) is closely linked to heightened cardiac dysfunction risk. Our study aimed to explore the additive effect of MAFLD on left ventricular (LV) deformation among T2DM patients, utilizing cardiac magnetic resonance (CMR) feature tracking technology. Methods This study retrospectively included 270 patients with T2DM, comprising 110 individuals with MAFLD and 160 without, alongside 80 age- and sex-matched healthy controls, all of whom underwent CMR examination. Parameters derived from CMR encompass those related to LV function and global strain metrics. LV global strain parameters include global radial peak strain (GRPS), longitudinal peak strain (GLPS), and circumferential peak strain (GCPS), peak systolic strain rate (PSSR), and peak diastolic strain rate (PDSR), measured across radial, circumferential, and longitudinal directions. Intergroup analysis, employing the Mann-Whitney U test, was utilized to compare LV function and global strain parameters. Results The LV function parameters, including LV end-diastolic volume (LVEDV), LVEDV index, LV end-systolic volume (LVESV), LVESVI, LV mass, and LV mass index, displayed a progressive augmentation from controls through T2DM patients without MAFLD, to those with MAFLD. In parallel, LVEF showed a declining trajectory across these groups. In contrast, LVSV and LVSVI were comparable among the three groups. In a similar vein, when examining global strain parameters derived from CMR, a significant and progressive deterioration is observed across the groups. GRPS, GCPS and GLPS, along with PSSR and PDSR in radial, circumferential, and longitudinal directions, manifest a pronounced decline moving from control subjects to T2DM patients without MAFLD, and further deteriorating in those with T2DM and MAFLD (All p-values < 0.05). To assess the effect of MAFLD severity on global peak strain, patients with T2DM and MAFLD were stratified into two groups: a mild MAFLD group (N=77) and a moderate to severe MAFLD group (N=33). Although there was a noticeable decline in GRPS, GCPS and GLPS, as well as in PSSR and PDSR across the three groups—from those without MAFLD to those with mild and then moderate to severe MAFLD—the observed differences did not reach statistical significance. The absence of statistical significance is likely due to the small sample sizes of the groups categorized by severity of MAFLD. Conclusions This study revealed that MAFLD has additive worsening effects on LV function and LV global strains in T2DM patients evaluated by CMR. Besides, moderate to severe MAFLD, compared to mild MAFLD, exhibits worse global strain parameters. Early detection and intervention of MAFLD might improve the prognosis of T2DM patients.

Prognostic value of cardiac magnetic resonance global circumferential strain assessed by feature tracking techniques in asymptomatic patients with significant aortic regurgitation

Abstract Introduction Cardiac magnetic resonance feature tracking (CMR-FT) deformation techniques have gained significant interest in recent years. They provide a comprehensive evaluation of myocardial function and improve the reproducibility of echocardiography strain techniques. Purpose The aim of this study was to evaluate whether CMR-FT deformation parameters play a role predicting worse clinical evolution in patients with chronic significant aortic regurgitation (AR) not meeting guidelines intervention criteria. Methods We included 85 patients with significant AR (moderate, moderate/severe, and severe) referred for CMR. Only asymptomatic patients with preserved left ventricle ejection fraction (LVEF) were considered for inclusion. Other concomitant myocardiopathies were excluded. Conventional functional left chambers parameters as well as myocardial deformation were evaluated, including global longitudinal strain (GLS), global circumferential strain (GCS) and global radial strain (GRS). A composite clinical major outcome was assessed, including admission heart failure admission, need for aortic valvule replacement and all-cause mortality. Results The mean age of the sample was 62 years old. One third of the patients were females. Other clinical baseline characteristics were not significantly different between groups when compared with Chi-squared and T-test statistical analysis. Mean follow-up was 42 months (±31). 21 patients presented with the composited outcome previously described. End-diastolic and end-systolic volumes did not differ between groups. Mean end-diastolic volume (EDV) was 196 ± 6.1 mL and mean end-systolic volume (ESV) was 88 ± 3.4 mL. Mean values of CMR-FT GLS, GCS and GRS were -14.1%, 22.8% and -16.9% respectively. GCS was selected as the best predictor for the combined endpoint point, with and area under the ROC curve of 0.67. A GCS value <-17% was selected as the optimal cut-off point. This value predicted events as is shown in Kaplan-Meier curves (HR 3.6, CI 95% 1.42 - 9.02, p = 0.007). A multivariate analysis showed that this association was independent of left ventricle (LV) ejection fraction, LV volumes and left atrial (LA) volume. Conclusion CMR-FT deformation parameters are impaired in significant AR patients even if intervention criteria are not met. A value of GCS < -17% in this population could predict a worse clinical evolution and emerges as a promising new tool helping clinical decision making in this challenging population.Kaplan-Meier curve free-event survival

Speckle tracking echocardiography for evaluation of myocardial functions before and after mitral valvuloplasty in dogs

BackgroundMyxomatous mitral valve disease (MMVD) is the most common acquired heart disease in dogs. Mitral valvuloplasty (MVP) addresses regurgitation, but the pre- and postoperative changes in myocardial function remain uncertain.ObjectivesThis study evaluated myocardial motion before and after MVP using two-dimensional speckle-tracking echocardiography (2D-STE).AnimalsEight client-owned dogs undergoing MVP for MMVD.MethodsMyocardial deformation was assessed by 2D-STE before surgery and at 1- and 3-months post-surgery. Measurements included left ventricular global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), cardiac twist, and right ventricular free wall GLS (RVFW-GLS).ResultsPostoperative decreases were observed in left ventricular internal dimensions, left atrial size, and early diastolic myocardial velocity, with an increase in peak late diastolic velocity. LV-GLS decreased at 1 month (−14.4%) and 3 months (−16.3%) compared to preoperative values (−24.4%) (p = 0.0078, p = 0.015). GCS decreased at 1 month (−12.9%) and 3 months (−14.8%) compared to preoperative values (−21.7%) (p = 0.0078). GRS decreased at 1 month (27.7%) and 3 months (32.0%) compared to preoperative values (67.7%) (p = 0.0078). No significant changes were observed in RVFW-GLS. Peak systolic twist increased at 3 months (9.1° vs. 4.9°, p = 0.039). Peak systolic apical rotation showed an upward trend at 3 months (p = 0.109). Left ventricular twist was mildly affected by LVIDd, LVIDDN, and sphericity index (R2 = 0.187, p = 0.034; R2 = 0.33, p = 0.0029; R2 = 0.22, p = 0.019).Conclusions and clinical importancePostoperative myocardial motion approached reference values, indicating significant improvement, particularly in left ventricular twisting motion. These findings highlight the positive impact of surgery on cardiac function in dogs with MMVD.

Impact of diabetes mellitus on right ventricular dysfunction and ventricular interdependence in hypertensive patients with heart failure with reduced ejection fraction assessed via 3.0 T cardiac MRI

BackgroundHypertension (HTN) and diabetes mellitus (DM) are two common comorbidities of heart failure with reduced ejection fraction (HFrEF), each of which can cause right ventricular (RV) dysfunction. The aim of this study was to investigate the impact of DM on RV dysfunction and ventricular interdependence in hypertensive HFrEF patients via cardiac magnetic resonance imaging (MRI) feature tracking.MethodsThis study included 249 patients with HFrEF: 77 HFrEF controls, 97 with hypertensive HFrEF (HTN-HFrEF [DM-]) and 75 with hypertensive HFrEF and comorbid DM (HTN-HFrEF [DM+]). The cardiac MRI-derived biventricular global radial (GRS), circumferential (GCS) and longitudinal (GLS) peak strains were obtained and compared among the groups. Multivariable linear regression and mediation analyses were used to evaluate the effects of DM and left ventricular (LV) strain on RV strain.ResultsThe biventricular GLS and GLS of segments 8, 9 and 14 of the interventricular septum (IVS) decreased gradually from the HFrEF control group to the HTN-HFrEF (DM−) group to the HTN-HFrEF (DM+) group (all P < 0.05). Patients with DM had even lower biventricular GCS and IVS strains in all directions in specific segments than did those without DM and the HFrEF controls (all P < 0.05). DM was independently associated with impaired RVGLS and RVGCS (both P < 0.05) in hypertensive HFrEF patients. The difference in RVGLS between the hypertensive HFrEF subgroups was partly mediated by LVGLS [β = 0.80, 95% CI (0.39–1.31)], and that of RVGCS was partly mediated by LVGCS [β = 0.28, 95% CI (0.01–0.62)].ConclusionsIn hypertensive HFrEF patients, comorbid DM may have aggravated RV dysfunction and was an independent determinant of impaired RV strain. RV dysfunction might be directly affected by DM and partially mediated by LV strain through unfavorable ventricular independence.

Effects of moderate-intensity aerobic training on cardiac structure and function in type 2 mellitus diabetic rats: Based on echocardiography and speckle tracking

PurposeThe present study aimed to evaluate the cardiac function changes using Layer-specific Speckle-tracking echocardiography (LS-STE) induced by Moderate-intensity aerobic training (MIAT) in Type 2 diabetes mellitus (T2DM) rats. MethodsTwenty-six rats were divided into four groups: the Control group (Con), the Training control group (CT), the T2DM group (DM), and the T2DM training group (DT). The CT and DT groups underwent an 8 weeks MIAT. Cardiac structure and function were evaluated by echocardiography and LS-STE. ResultsCompared with the Con group, left atrial diameter (LAD), left ventricular end-diastolic diameter(LVEDD), relation wall thickness (RWT), and left ventricular mass (LVM) were significantly higher, and the endo-, mid-, and epi-longitudinal strain (LS), global radial strain (GRS), and endo- and mid-circumferential strain (CS) were significantly lower in DM rats (all p < 0.05). The endo-, mid-, and epi-LS, GRS, endo- and mid-CS were increased in DT rats compared with DM rats (all p < 0.05). Compared with Con rats, CT rats had a significant increase in LVEDD and LVM (all p < 0.05), meanwhile myocardial strains had no significant differences (all p > 0.05). ConclusionLS-STE was a sensitive method to assess subclinical myocardial changes in T2DM rats. MIAT had the benefit of reversing cardiac systolic subclinical dysfunction in T2DM rats.

Three Dimensions global radial strain and coronary artery disease severity

Three Dimensions global radial strain and coronary artery disease severity

Blood eosinophil count is associated with early atherosclerotic artery changes in asthma

ObjectiveAsthma is linked to atherosclerosis, yet the underlying mediators remain elusive. Eosinophils may contribute to both asthmatic and atherosclerotic inflammation. Hence, this study aimed to explore the potential associations of eosinophils with artery changes among patients with asthma.MethodsWe assessed strain values of the common carotid arteries (CCAs) via vascular speckle tracking and compared asthma patients with low (< 300/µl) and high (≥ 300/µl) blood eosinophil counts (BEC).ResultsWe enrolled 100 patients, 42 with a BEC of < 300 and 58 with a BEC of ≥ 300 n/µl. Patients with high BEC exhibited more severe disease, characterized, e.g., by a higher frequency of acute exacerbations (1.3 ± 2.1 vs. 2.6 ± 2.4 n/year, p = 0.005). Both groups presented similar profiles in terms of conventional cardiovascular risk. The high BEC group demonstrated elevated arterial stiffness, reflected by reduced radial strain (mean radial strain of the right CCA: 2.7 ± 1.4% for BEC ≥ 300 n/µl vs. 3.5 ± 1.7% for BEC < 300 n/µl, p = 0.008; left CCA: 2.6 ± 1.4% vs. 4.1 ± 2.2%, p < 0.001). A weak yet statistically significant negative correlation was observed between BEC and radial strain for the right CCA (R2 = 0.131, b=-0.001, p = 0.001) and left CCA (R2 = 0.086, b=-0.001, p = 0.015). However, the prevalence of cerebrovascular disease was similar in both groups (31,0% vs. 50,0%, p = 0.057).ConclusionWe identified a correlation between BEC and vascular stiffness, which supports the hypothesis that eosinophils may promote atherosclerosis.Clinical trial numberDue to the exploratory and predominantly retrospective nature of the study, trial registration was not conducted. The only prospective procedure conducted was the angiological sonography to evaluate the current state. No ensuing health-related interventions were performed specifically for this study.

Novel Insights into Causal Effects of Serum Lipids and Apolipoproteins on Cardiovascular Morpho-Functional Phenotypes.

Previous observational studies have explored the association between serum lipids, apolipoproteins, and adverse ventricular/aortic structure and function. However, whether a causal link exists is uncertain. This study employed a two-sample Mendelian randomization (MR), colocalization, reverse, and multivariable MR (MVMR) approach to examine the causal associations among five serum lipids, two apolipoproteins, and 32 cardiac magnetic resonance (CMR) traits. Utilizing single-nucleotide polymorphisms (SNPs) linked to serum lipids and apolipoproteins as instrumental variables. CMR traits from seven independent genome-wide association studies served as preclinical endophenotypes, offering insights into aortic and cardiac structure/function. The primary analysis utilized a random-effects inverse variance method (IVW), followed by sensitivity and validation analyses. In the primary IVW MR analyses, genetically predicted low-density lipoprotein cholesterol (LDL-C) levels were positively correlated with increased descending aorta strain (DAo strain) (β = 0.098; P = 2.69E-07) and ascending aorta strain (AAo strain) (β = 0.079; P = 5.19E-05). Genetically predicted high-density lipoprotein cholesterol (HDL-C) levels were positively correlated with left ventricular radial peak diastolic strain rate (LV-PDSRll) (β = 0.176; P = 2.89E-05) and the left ventricular longitudinal peak diastolic strain rate (LV-PDSRrr) (β = 0.059; P = 2.44E-06), and negatively correlated with left ventricular regional wall thickness (LVRWT). While apolipoprotein B (ApoB) levels were positively correlated with AAo strain (β = 0.076; P = 1.16E-05), DAo strain (β = 0.065; P = 2.77E-05). A shared causal variant was identified to demonstrate the associations of ApoB with AAo strain and DAo strain using colocalization analysis. Sensitivity analyses confirmed the robustness of these associations. Targeting lipid and apolipoprotein levels through interventions may provide novel strategies for the primary prevention of CVDs.

Myocardial strain analysis by feature tracking cardiac magnetic resonance to identify subclinical cardiac dysfunction in patients with MINOCA

BackgroundTo investigate whether feature tracking cardiac magnetic resonance (FT-CMR) can identify subclinical myocardial dysfunction in patients with myocardial infarction with non-obstructed coronary arteries (MINOCA).MethodsClinical data and CMR images of MINOCA patients (N = 46) and control individuals (N = 12) were compared. The infarct and edema volume to total myocardium, peak global longitudinal strain (GLS), global longitudinal strain rate (GLSR), peak global circumferential strain (GCS), global circumferential strain rate, peak global radial strain, and global radial strain rate were measured. Diagnostic performances of strain parameters for MINOCA were evaluated by logistic regression and receiver operating characteristics analysis.ResultsExcept smoking history, the two groups showed no significant differences in cardiovascular risk factors and traditional heart function. GLS (-14.67 ± 1.96% vs. -19.19 ± 2.05%), GLSR (-0.94 ± 0.16 S− 1 vs. -1.23 ± 0.14 S− 1) and GCS (-17.59 ± 1.81% vs. -19.22 ± 1.76%) were impaired in MINOCA patients compared with the control group. MINOCA patients with normal routine CMR showed abnormalities in GLS (-16.23 ± 1.16%) and GLSR (-1.04 ± 0.16 S− 1). GLS and GLSR were predictive for MINOCA diagnosis (P = 0.002 vs. P = 0.033). GLS correlated strongly with myocardial infarction and edema. The optimal diagnostic threshold for GLS was <-16.9% for MINOCA diagnosis (sensitivity 87.1%, specificity 92.9%); the area under the receiver operating characteristic curve was 0.968.ConclusionsMyocardial strain by FT-CMR may effectively detect early myocardial impairment with MINOCA, especially in patients with normal routine MRI.

Usefulness of tissue tracking to differentiate tachycardia-induced cardiomyopathy from dilated cardiomyopathy in patients admitted for heart failure.

Differentiation of tachycardia-induced cardiomyopathy (TIC) from dilated cardiomyopathy (DCM) in patients admitted for heart failure (HF) with left ventricular dysfunction and supraventricular tachyarrhythmia (SVT) remains challenging. The role of tissue tracking (TT) in this setting remains unknown. Forty-three consecutive patients admitted for HF due to SVT with left ventricular ejection fraction (LVEF) < 50% undergoing CMR were retrospectively included. Those eventually evolving to LVEF > 50% at follow-up were classified as TIC and those maintaining a LVEF < 50% were classified as DCM. Clinical, echocardiography, and CMR findings, including TT, were analyzed to predict LVEF recovery. Twenty-five (58%) patients were classified as TIC. Late gadolinium enhancement (LGE) was more frequent in DCM group (61% vs 16%, p = 0.004). Left ventricle (LV) peak systolic radial velocity and peak diastolic radial strain rate were lower in DCM group (7.24 ± 4.44mm/s vs 10.8 ± 4.5mm/s; p = 0.015 and -0.12 ± 0.33 1/s vs -0.48 ± 0.51 1/s; p = 0.016, respectively). Right ventricle (RV) peak circumferential displacement was lower in patients with TIC (0.2 ± 1.3 vs 1.3 ± 0.9°; p = 0.009). In the multivariate analysis, diabetes (p = 0.046), presence of LGE (p = 0.028), LV peak systolic radial velocity < 7.5mm/s (p = 0.034), and RV peak circumferential displacement > 0.5° (p = 0.028) were independent predictors of lack of LVEF recovery. In the setting of acute HF with LV dysfunction related to SVT, diabetes, LGE, LV peak systolic velocity, and RV peak circumferential displacement are independent predictors of lack of LVEF recovery and, therefore, represent clinically useful parameters to differentiate TIC from DCM.

Impact of systemic lupus erythematosus on cardiovascular morphologic and functional phenotypes: a Mendelian randomization analysis.

Previous studies have established a correlation between systemic lupus erythematosus (SLE) and cardiovascular health, but the potential causal effects of SLE on heart function and structure remain poorly understood. Cardiovascular magnetic resonance imaging (CMR), a novel non-invasive technique, provides a unique assessment of cardiovascular structure and function, making it an essential tool for evaluating the risk of heart disease. In this study, we performed a Mendelian randomization analysis to determine the causal relationship between SLE and CMR traits. Genetic variants independently linked to SLE were selected from a genome-wide association study (GWAS) containing 5,201 cases and 9,066 controls as instrumental variables. A set of 82 CMR traits was obtained from a recent GWAS, serving as preclinical indicators and providing preliminary insights into the morphology and function of the four cardiac chambers and two aortic segments. Primary analysis employed a two-sample Mendelian randomization study using the inverse-variance weighted method. Heterogeneity testing, sensitivity analyses, and instrumental variable strength assessments confirmed the robustness of the findings. SLE exhibited a correlation with increased stroke volume (βLVSV = 0.007, P = 0.045), regional peak circumferential strain (βEcc_AHA_9 = 0.013, P = 0.002; βEcc_AHA_12 = 0.009, P = 0.043; βEcc_AHA_14 = 0.013, P = 0.006), and global peak circumferential strain of the LV (βEcc_global = 0.010, P = 0.022), as well as decreased regional radial strain (βErr_AHA_11 = -0.010, P = 0.017). This research presents evidence of a potential causal association between traits of SLE and alterations in cardiac function, guiding cardiac examinations and disease prevention in lupus patients.

The transition from hypertension to hypertensive heart disease and heart failure with preserved ejection fraction: a retrospective cross-sectional study of myocardial magnetic resonance strain and tissue characteristics.

Due to the variability of symptoms and signs associated with heart failure, along with the lack of specific tests for definitive diagnosis, the noninvasive diagnosis of heart failure with preserved ejection fraction (HFpEF) continues to pose significant clinical challenges. This investigation was designed to elucidate the clinical manifestations of HFpEF and to analyze cardiac magnetic resonance (CMR)-derived myocardial strain metrics and tissue characteristics in a cohort exhibiting HFpEF with hypertension (HFpEF-HTN). This retrospective analysis consisted of 128 patients diagnosed HFpEF-HTN, 78 individuals with hypertensive heart disease (HHD), 89 individuals with hypertension (HTN), and 60 normotensive healthy controls and was conducted from August 2021 to February 2024. All participants were recruited from The First Hospital of Lanzhou Universityand underwent laboratory examinations and 3.0 T CMR. The study compared clinical features and CMR-derived structural and functional parameters across different groups. Logistic regression was employed to determine the association between CMR parameters and HFpEF-HTN. Spearman correlation coefficient analysis was used to clarify the relationship between myocardial strain parameters and left ventricular (LV) ejection fraction and right ventricular (RV) ejection fraction. Additionally, the area under the curve (AUC) from receiver operating characteristic (ROC) analysis was used to compare the diagnostic performance of different CMR parameters for HFpEF-HTN. Patients diagnosed with (HFpEF-HTN) were characterized by an older demographic profile, a higher prevalence of smoking history, elevated systolic and diastolic blood pressure, increased levels of N-terminal pro-brain natriuretic peptide, and more advanced New York Heart Association functional class as compared to other studied groups. In terms of myocardial deformation, individuals with HFpEF-HTN exhibited pronounced impairments in both LV and RV function, as evidenced by significantly reduced longitudinal strain (LS), circumferential strain (CS), and radial strain (RS), relative to HTN, HHD, the control cohorts (all P values <0.001). Patients with HFpEF-HTN showed significantly elevated levels of late gadolinium enhancement, native T1, and extracellular volume fraction (ECV) indicative of myocardial interstitial fibrosis as compared to patients with HHD. Additionally, as compared to ECV, LV GCS emerged as a superior diagnostic indicator, demonstrating greater diagnostic accuracy in differentiating HFpEF-HTN patients from those with HHD (AUC =0.85; P<0.001). Moreover, LVEF showed a mild correlation with CMR-derived LV GLS (R=-0.43; P<0.001), LV GCS (R=-0.42; P<0.001), and LV GRS, (R=0.56; P<0.001) in all patients. Myocardial strain, T1 mapping, and ECV can be used for the quantitative evaluation of LV and RV ventricular remodeling, dysfunction, and tissue characteristics in patients with HFpEF-HTN and thus hold significant potential for the diagnosis of these patients.

Comparing continuum and direct fiber models of soft tissues: An ocular biomechanics example reveals that continuum models may artificially disrupt the strains at both the tissue and fiber levels

Collagen fibers are the main load-bearing component of soft tissues but difficult to incorporate into models. Whilst simplified homogenization models suffice for some applications, a thorough mechanistic understanding requires accurate prediction of fiber behavior, including both detailed fiber-level strains and long-distance transmission. Our goal was to compare the performance of a continuum model of the optic nerve head (ONH) built using conventional techniques with a fiber model we recently introduced which explicitly incorporates the complex 3D organization and interaction of collagen fiber bundles [1]. To ensure a fair comparison, we constructed the continuum model with identical geometrical, structural, and boundary specifications as for the fiber model. We found that: 1) although both models accurately matched the intraocular pressure (IOP)-induced globally averaged displacement responses observed in experiments, they diverged significantly in their ability to replicate specific 3D tissue-level strain patterns. Notably, the fiber model faithfully replicated the experimentally observed depth-dependent variability of radial strain, the ring-like pattern of meridional strain, and the radial pattern of circumferential strain, whereas the continuum model failed to do so; 2) the continuum model disrupted the strain transmission along each fiber, a feature captured well by the fiber model. These results demonstrate limitations of the conventional continuum models that rely on homogenization and affine deformation assumptions, which render them incapable of capturing some complex tissue-level and fiber-level deformations. Our results show that the strengths of explicit fiber modeling help capture intricate ONH biomechanics. They potentially also help modeling other fibrous tissues. Statement of SignificanceUnderstanding the mechanics of fibrous tissues is crucial for advancing knowledge of various diseases. This study uses the ONH as a test case to compare conventional continuum models with fiber models that explicitly account for the complex fiber structure. We found that the fiber model captured better the biomechanical behaviors at both the tissue level and the fiber level. The insights gained from this study demonstrate the significant potential of fiber models to advance our understanding of not only glaucoma pathophysiology but also other conditions involving fibrous soft tissues. This can contribute to the development of therapeutic strategies across a wide range of applications.

The Predictive Value of Global Longitudinal and Circumferential Strains in Hypertensive Patients: 10-Year Follow-Up

Background: The aim of the current study was to investigate the predictive value of a multidirectional LV strain on adverse outcomes in a large population of uncomplicated hypertensive patients who were followed for a mean period of 10 years. Methods: This retrospective study included 591 recently diagnosed hypertensive patients who underwent clinically indicated echocardiography between January 2010 and December 2014 and were followed for a mean period of 10 years. Global longitudinal, circumferential and radial strains (GLS, GCS and GRS) were measured by 2D speckle tracking imaging. The primary outcome was a MACE occurrence defined by all-cause mortality, cardiovascular mortality, myocardial infarction, coronary artery by-pass, coronary stent implantation, stroke, development of heart failure and the occurrence of atrial fibrillation during follow-up. Results: Our results showed that GLS, GCS and GRS were significantly lower in patients who experienced MACE. Age, male gender, systolic blood pressure, left ventricular hypertrophy (LVH) and left atrial enlargement (LAE) were associated with MACE occurrence. Reduced GLS [OR 1.15; 95%CI: 1.01–1.30] and reduced GCS [OR 1.1; 95%CI: 1.02–1.22] were related with MACE independently of clinical characteristics, LV systolic and diastolic function, as well as LVH. Reduced GRS was not independently associated with adverse outcomes. Conclusions: Reduced GLS and GCS were independently associated with adverse outcomes during 10-year follow-up in patients who were recently diagnosed and uncomplicated hypertensive patients at the baseline.

Subacute and long-term effects of COVID-19 on cardiac health and function in German elite athletes assessed by strain analysis: a speckle tracking echocardiography observational trial

Abstract Introduction During the COVID-19-pandemic, most elite athletes were infected with the novel severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Initial worries of high rates of multi-organ complications including the heart and ending sporting careers were disproved by large studies. However, the effects of COVID-19 on the heart and its function in elite athletes remains unclear, especially in the prolonged post-infection follow-up and during and after return to competition. Methods In the year 2020, a cohort of 127 elite athletes (boasting an accumulated 58 Olympic and world championship medals) was recruited, 76 of them recently having undergone a SARS-CoV-2 infection. Echocardiography was conducted 1 (T0), 5 (T1) and 9 (T2) months after the infection in the infected cohort and at baseline for the control cohort. Left-ventricular global longitudinal, circumferential, and radial strain was compared cross-sectionally at baseline between athletes after a COVID-19-infection and control athletes, as well as longitudinally in the COVID-19-cohort. Results At baseline, global longitudinal strain (reported as absolute %-values) was significantly higher in the COVID-19-cohort in comparison to control-cohort (20.37 ± 1.98% vs. 19.41 ± 2.11%, respectively, p = 0.042). In the longitudinal assessment within the COVID-19-cohort the global longitudinal strain was significantly higher shortly after the infection (T0) than at the two follow-up measurements (T0: 20.37 ± 1.98%; T1: 19.34 ± 1.65%; T2: 19.30 ± 1.68% (p = 0.0052 and p = 0.0044, respectively)). No significant differences for any of the comparisons were found for circumferential or radial strain. Discussion The significantly elevated values in the COVID-19-cohort at T0 may be due to an affectation of the autonomic nervous system, which has previously been documented as a result of COVID-19-disease. No cardiac injury after COVID-19 was detected using strain analysis. All documented global longitudinal strain values were within the normal range for athletes. A return to training and competition had no deleterious effect on cardiac health in athletes after a COVID-19-infection in this trial.