Global Peak Circumferential Strain Research Articles

Prognostic Value of Segmental Strain After ST-Elevation Myocardial Infarction: Insights From the EARLY Assessment of MYOcardial Tissue Characteristics by Cardiac Magnetic Resonance (EARLY-MYO-CMR) Study.

The prognostic value of left ventricular segmental strain (SS) in ST-elevation myocardial infarction (STEMI) remains unclear. To assess the prognostic value and application of SS. Retrospective analysis of a prospective registry. Five hundred and forty-four patients after STEMI (500 in Cohort 1, 44 in Cohort 2). 3 T, balanced steady-state free precession, gradient echo, and gradient echo contrast-enhanced images. Participants underwent cardiac MR during the acute phase after STEMI. Infarct-related artery (IRA) strain was determined based on SS obtained from cine images. The primary endpoint was the composite of major adverse cardiovascular events (MACEs) after 8 years of follow-up. In Cohort 2, SS stability was assessed by MR twice within 8 days. Contrast and non-contrast risk models based on SS were established, leading to the development of an algorithm. Student's t-test, Mann-Whitney U-test, Cox and logistic regression, Kaplan-Meier analysis, net reclassification index (NRI). P < 0.05 was considered significant. During a median follow-up of 5.2 years, 83 patients from Cohort 1 experienced a MACE. Among SS, IRA peak circumferential strain (IRA-CS) was an independent factor for MACEs (adjusted hazard ratio 1.099), providing incremental prognostic value (NRI 0.180, P = 0.10). Patients with worse IRA-CS (>-8.64%) demonstrated a heightened susceptibility to MACE. Additionally, IRA-CS was significantly associated with microvascular obstruction (MVO) (adjusted odds ratio 1.084) and infarct size (r = 0.395). IRA-CS showed comparable prognostic effectiveness to global peak circumferential strain (NRI 0.100, P = 0.39), also counterbalancing contrast and non-contrast risk models (NRI 0.205, P = 0.05). In Cohort 2, IRA-CS demonstrated stability between two time points (P = 0.10). Based on risk models incorporating IRA-CS, algorithm "HJKL" was preliminarily proposed for stratification. IRA-CS is an important prognostic factor, and an algorithm based on it is proposed for stratification. 4 TECHNICAL EFFICACY: Stage 2.

Identification of patients with nonischemic dilated cardiomyopathy at risk of malignant ventricular arrhythmias: insights from cardiac magnetic resonance feature tracking

BackgroundPatients with nonischemic dilated cardiomyopathy (NIDCM) are prone to arrhythmias, and the cause of mortality in these patients is either end-organ dysfunction due to pump failure or malignant arrhythmia-related death. However, the identification of patients with NIDCM at risk of malignant ventricular arrhythmias (VAs) is challenging in clinical practice. The aim of this study was to evaluate whether cardiovascular magnetic resonance feature tracking (CMR-FT) could help in the identification of patients with NIDCM at risk of malignant VAs.MethodsA total of 263 NIDCM patients who underwent CMR, 24-hour Holter electrocardiography (ECG) and inpatient ECG were retrospectively evaluated. The patients with NIDCM were allocated to two subgroups: NIDCM with VAs and NIDCM without VAs. From CMR-FT, the global peak radial strain (GPRS), global longitudinal strain (GPLS), and global peak circumferential strain (GPCS) were calculated from the left ventricle (LV) model. We investigated the possible predictors of NIDCM combined with VAs by univariate and multivariate logistic regression analyses.ResultsThe percent LGE (15.51 ± 3.30 vs. 9.62 ± 2.18, P < 0.001) was higher in NIDCM patients with VAs than in NIDCM patients without VAs. Furthermore, the NIDCM patients complicated with VAs had significantly lower GPCS than the NIDCM patients without VAs (− 5.38 (− 7.50, − 4.22) vs.−9.22 (− 10.73, − 8.19), P < 0.01). Subgroup analysis based on LGE negativity showed that NIDCM patients complicated with VAs had significantly lower GPRS, GPCS, and GPLS than NIDCM patients without VAs (P < 0.05 for all). Multivariate analysis showed that both GPCS and %LGE were independent predictors of NIDCM combined with VAs.ConclusionsCMR global strain can be used to identify NIDCM patients complicated with VAs early, specifically when LGE is not present. GPCS < − 13.19% and %LGE > 10.37% are independent predictors of NIDCM combined with VAs.

Utilizing Artificial Intelligence-Based Deformable Registration for Global and Layer-Specific Cardiac MRI Strain Analysis in Healthy Children and Young Adults

The absence of published reference values for multilayer-specific strain measurement using cardiac magnetic resonance (CMR) in young healthy individuals limits its use. This study aimed to establish normal global and layer-specific strain values in healthy children and young adults using a deformable registration algorithm (DRA). A retrospective study included 131 healthy children and young adults (62 males and 69 females) with a mean age of 16.6±3.9 years. CMR examinations were conducted using 1.5T scanners, and strain analysis was performed using TrufiStrain research prototype software (Siemens Healthineers, Erlangen, Germany). Global and layer-specific strain parameters were extracted from balanced Steady-state free precession cine images. Statistical analyses were conducted to evaluate the impact of demographic variables on strain measurements. The peak global longitudinal strain (LS) was -16.0±3.0%, peak global radial strain (RS) was 29.9±6.3%, and peak global circumferential strain (CS) was -17.0±1.8%. Global LS differed significantly between males and females. Transmural strain analysis showed a consistent pattern of decreasing LS and CS from endocardium to epicardium, while radial strain increased. Basal-to-apical strain distribution exhibited decreasing LS and increasing CS in both global and layer-specific analysis. This study uses DRA to provide reference values for global and layer-specific strain in healthy children and young adults. The study highlights the impact of sex and age on LS and body mass index on RS. These insights are vital for future cardiac assessments in children, particularly for early detection of heart diseases.

Additional Impact of Aortic Regurgitation on Left Ventricular Strain and Remodeling in Essential Hypertension Patients Evaluated Using MRI.

Understanding the impact of aortic regurgitation (AR) on hypertensive patients' hearts is important. To assess left ventricular (LV) strain and structure in hypertensive patients and investigate the relationship with AR severity. Retrospective. 263 hypertensive patients (99 with AR) and 62 controls, with cardiac MRI data. Balanced steady-state free precession (bSSFP) sequence at 3.0T. AR was classified as mild, moderate, or severe based on echocardiographic findings. LV geometry was classified as normal, concentric remodeling, eccentric hypertrophy, or concentric hypertrophy based on MRI assessment of LV mass/volume ratio and LV Mass index (LVMI). LV global radial peak strain (GRPS), global circumferential peak strain (GCPS), and global longitudinal peak strain (GLPS) were obtained by post-processing bSSFP cine datasets using commercial software. ANOVA, Kruskal-Wallis test, Spearman's correlation coefficients (r), chi-square test, and multivariable linear regression analysis. A P value <0.05 was considered statistically significant. Hypertensive patients with AR had significantly lower LV myocardial strain and higher LVMI than the group without AR (GRPS 26.25 ± 12.23 vs. 34.53 ± 9.85, GCPS -17.4 ± 5.84 vs. -20.57 ± 3.57, GLPS -9.86 ± 4.08 vs. -12.95 ± 2.94, LVMI 90.56 ± 38.56 vs.58.84 ± 17.55). Of the 99 patients with AR, 56 had mild AR, 26 had moderate AR and 17 had severe AR. The degree of AR was significantly negatively correlated to the absolute values of LV GRPS, GCPS and GLPS (r = -0.284 - -0.416). LV eccentric hypertrophy increased significantly with AR severity (no AR 21.3%, mild AR 42.9%, moderate AR 73.1%, severe AR 82.4%). In multivariable analysis, the degree of AR was an independent factor affecting LV global strain and LVMI even after considering confounding factors (β values for global myocardial strain were -0.431 to -0.484, for LVMI was 0.646). Increasing AR severity leads to decreased cardiac function and worse ventricular geometric phenotypes in hypertensive patients. 4 TECHNICAL EFFICACY: Stage 3.

Dynamic changes in cardiac morphology, function, and diffuse myocardial fibrosis duration of diabetes in type 1 and type 2 diabetic mice models using 7.0 T CMR and echocardiography.

Diabetes mellitus (DM) is associated with an increased risk of cardiovascular disease (CVD). Hence, early detection of cardiac changes by imaging is crucial to reducing cardiovascular complications. Early detection of cardiac changes is crucial to reducing cardiovascular complications. The study aimed to detect the dynamic change in cardiac morphology, function, and diffuse myocardial fibrosis(DMF) associated with T1DM and T2DM mice models. 4-week-old C57Bl/6J male mice were randomly divided into control (n=30), T1DM (n=30), and T2DM (n=30) groups. A longitudinal study was conducted every 4 weeks using serial 7.0T CMR and echocardiography imaging. Left ventricular ejection fraction (LV EF), tissue tracking parameters, and DMF were measured by cine CMR and extracellular volume fraction (ECV). Global peak circumferential strain (GCPS), peak systolic strain rate (GCPSSR) values were acquired by CMR feature tracking. LV diastolic function parameter (E/E') was acquired by echocardiography. The correlations between the ECV and cardiac function parameters were assessed by Pearson's test. A total of 6 mice were included every 4 weeks in control, T1DM, and T2DM groups for analysis. Compared to control group, an increase was detected in the LV mass and E/E' ratio, while the values of GCPS, GCPSSR decreased mildly in DM. Compared to T2DM group, GCPS and GCPSSR decreased earlier in T1DM(GCPS 12W,P=0.004; GCPSSR 12W,P=0.04). ECV values showed a significant correlation with GCPS and GCPSSR in DM groups. Moreover, ECV values showed a strong positive correlation with E/E'(T1DM,r=0.757,P<0.001;T2DM, r=0.811,P<0.001). The combination of ECV and cardiac mechanical parameters provide imaging biomakers for pathophysiology, early diagnosis of cardiac morphology, function and early intervention in diabetic cardiomyopathy in the future.

Abstract 12980: Left Ventricular Alterations in Neonatal Encephalopathy - A Case-Control Study Using 3D Echocardiography

Introduction: Despite therapeutic hypothermia (TH), neonates with neonatal encephalopathy (NE) often present with multi-organ dysfunction, including cardiac alterations in the first days of life. Objectives: Describe the cardiac performance of neonates with moderate to severe NE treated with TH using three-dimensional echocardiography (3D-ECHO) relative to a control population without NE. Methods: Single-centre prospective case-control study of neonates with moderate to severe NE treated with TH between 2019 and 2021, compared to healthy neonates. The control group were newborns recruited in the nursery without need for resuscitation. 3D-ECHO was performed on day of life (DOL) 2. Left ventricular (LV) metrics were measured using 3D-Speckle Tracking Echocardiography. Descriptive statistics were used to compare the two groups. Results: We included 16 neonates with NE and 50 controls. Birthweight and gestational age at birth were similar (Table 1). Neonates with NE had lower systolic blood pressure (BP) but similar diastolic BP at ECHO, while 11/16 were exposed to cardiovascular medications at ECHO. These neonates had lower LV end-diastolic volume (4.2 [1.2] vs 5.0 [1.4] mL; p=0.04), lower stroke volume (2.2 [0.7] vs 2.9 [0.8] mL; p=0.002) and lower ejection fraction (52 [6] vs 56 [8] %; p=0.0008). These infants also had lower peak global circumferential strain (-25 [5] vs -28 [5] %; p=0.03). The association between NE and LV-ejection fraction remained significant after adjusting for weight (b=-5.7%, 95% Confidence Interval [-9.2; -2.2], p=0.002). Conclusions: Neonates with moderate to severe NE had reduced LV functional markers on DOL 2 as comparted to healthy controls. They had decreased systolic BP and LV end diastolic volume. These findings may be secondary to the asphyxia, catecholamines and medications exposure, or to TH. Future studies should consider 3D-ECHO as a modality to investigate these patients and the impact of therapeutic interventions.

Left Ventricular Function and Dimensions Are Altered Early in Infants Developing Brain Injury in the Setting of Neonatal Encephalopathy

We evaluated the association between left cardiac 3-dimensional echocardiographic parameters and brain injury in a single-center prospective study of neonates with neonatal encephalopathy. On day 2 of life, neonates with brain injury had greater left ventricle end-diastolic and stroke volume but also greater peak global circumferential strain detected by 3-dimensional echocardiogram.

The Role of Strain by Cardiac Magnetic Resonance Imaging in Predicting the Prognosis of Patients with Chronic Thromboembolic Pulmonary Hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by thrombotic obstruction of the pulmonary arteries, and right ventricular (RV) dysfunction is a major cause of death. Cardiac magnetic resonance (CMR) is the gold standard for assessing heart wall deformation; therefore, we aimed to determine the prognostic value of CMR strain in patients with CTEPH. Strain derived by CMR was measured at the time of diagnosis in 45 patients with CTEPH, and the relationship between RV strain and prognosis was determined through follow-up. The value of RV strain in the prognostic model was compared with that of pulmonary arterial hypertension (PAH) risk stratification. The RV global peak longitudinal strain (GLS) and global peak circumferential strain (GCS) in CTEPH patients were lower than the normal references of RV strain in the control group. GLS and longitudinal strain in the basal segment were independent risk factors for adverse events (P < .050). Adding CMR parameters to PAH risk stratification improved its predictive power in patients with CTEPH. GLS and GCS scores were impaired in patients with chronic RV overload. RV strain derived by CMR imaging is a promising noninvasive tool for the follow-up of patients with CTEPH.

TRANSTHORACIC SHOCKS LEAD TO REGIONAL BI-VENTRICULAR DIASTOLIC DYSFUNCTION IN TERRITORIES WITH ACUTE MYOCARDIAL INJURY

<h3>Introduction</h3> Electric defibrillations and cardioversion are standard interventions to terminate arrhythmia. Recent evidence hints to acute post shock myocardial injury. However, that injury may follow unique pathways in every individual. Common functional measures such as ejection fraction are limited in that they represent only global ventricular function. Cardiovascular magnetic resonance feature tracking (CMR-FT) is a technique that can quantify myocardial contraction and relaxation on a regional level. The purpose of this analysis was to investigate the impact of acute myocardial injury after serial transthoracic shocks on regional systolic and diastolic myocardial deformation in a healthy animal model. <h3>Methods</h3> Ten healthy anaesthetized swine were scanned in a 3 Tesla MRI with a standard short axis cine and a clinical T1 mapping sequence in three short axis slices to detect myocardial edema. Five transthoracic shocks with 200 Joules each were applied within five minutes. Five hours post-shock the same images were re-acquired. Six control animals underwent the same protocol without shocks. Changes in regional peak strain as a measure of systolic function, and early diastolic strain rate as a measure of diastolic function were evaluated using CMR-FT analysis in circumferential orientation for both the left (LV) and right ventricle (RV). T1 maps of the LV were analyzed and reported per myocardial AHA segment as a measure of myocardial edema. For the RV, a region of interest (ROI) was contoured in each of the 3 short-axis slices. The regional changes in strain in comparison to the development of myocardial injury (ΔT1 mapping) over the course of 5h were statistically assessed using a mixed effects model accounting for the electrical intervention and multiple measurements per individual. <h3>Results</h3> Global circumferential peak strain worsened in both ventricles (LV: -15.6±3.3% to -13.0±3.6%, p<0.01; RV: -16.1±2.3% to -12.8±4.8%, p=0.03). Additionally, LV early diastolic strain rate slowed from baseline to the 5h timepoint (1.19±0.35 to 0.95±0.37/s, p = 0.02) in shocked animals. Whereas no change was observed for any global strain parameters in the control group. There was no linear association with regional LV peak strain with T1 changes (p=0.97). However, an increase in T1 was colocalized to a reduction in early diastolic strain rate (p = 0.03), where early diastolic strain rate slowed by -0.25/s every 100ms increase in T1. On the other hand, both RV systolic and diastolic function worsened in the presence of increased regional RV T1 with a change in peak strain of 2.7% and a deceleration of diastolic strain rate (–0.42/s) per 100ms increase in RV T1 (p<0.05). <h3>Conclusions</h3> Serial transthoracic shock in a healthy swine model attenuate biventricular systolic function, but it is the development of regional diastolic dysfunction that is associated with the onset of colocalized myocardial edema. Future studies are warranted to assess these effects of electrical interventions in clinical settings.

Evaluate the elasticity of carotid artery in the type 2 diabetes mellitus patients with nonalcoholic fatty liver disease by two-dimensional strain imaging.

To evaluate carotid elasticity by using two-dimensional strain imaging (2DSI) in type 2 diabetes mellitus (T2DM) patients with nonalcoholic fatty liver disease (NAFLD). 98 patients with T2DM diagnosed in our hospital were selected. All the patients were without carotid plaque, which were proved by carotid ultrasonography. According to the fatty liver classification standard, patients were divided into three groups. There were 35 cases without NAFLD in group A, 33 cases with mild NAFLD in group B and 30 cases with moderate to severe NAFLD in group C. By using two-dimensional and M-mode ultrasound to measure the left carotid intima-media thickness (IMT), common carotid arterial systolic diameter (Ds) and diastolic diameter (Dd). The systolic peak velocity was measured by spectral Doppler ultrasound. The systolic global peak circumferential strain (CS), early and late systolic global circumferential strain rate (CSr) were measured by 2DSI. The stiffness parameters β1 and β2 were calculated by M-mode ultrasound and 2DSI separately. Among three groups, the Ds, Dd and systolic peak velocity showed no significant difference (all P > .05). In group C, IMT and β1 were obviously increased than those of groups A and B (all P < .05). Compared groups A and B, there were no significant difference in IMT and β1 (all P > .05). β2 was higher in groups B and C than those in group A, CS, CSr were lower in groups B and C than those in group A (both P > .05). The carotid elasticity of T2DM patients with NAFLD can be evaluated by 2DSI.

Segmental strain for scar detection in acute myocardial infarcts and in follow-up exams using non-contrast CMR cine sequences

BackgroundThe purpose of the study was to investigate feasibility of infarct detection in segmental strain derived from non-contrast cardiac magnetic resonance (CMR) cine sequences in patients with acute myocardial infarction (AMI) and in follow-up (FU) exams.Methods57 patients with AMI (mean age 61 ± 12 years, CMR 2.8 ± 2 days after infarction) were retrospectively included, FU exams were available in 32 patients (35 ± 14 days after first CMR). 43 patients with normal CMR (54 ± 11 years) served as controls. Dedicated software (Segment CMR, Medviso) was used to calculate global and segmental strain derived from cine sequences. Cine short axis stacks and segmental circumferential strain calculations of every patient and control were presented to two blinded readers in random order, who were advised to identify potentially infarcted segments, blinded to LGE and clinical information.ResultsImpaired global strain was measured in AMI patients compared to controls (global peak circumferential strain [GPCS] p = 0.01; global peak longitudinal strain [GPLS] p = 0.04; global peak radial strain [GPRS] p = 0.01). In both imaging time points, mean segmental peak circumferential strain [SPCS] was impaired in infarcted tissue compared to remote segments (AMI: p = 0.03, FU: p = 0.02). SPCS values in infarcted segments were similar between AMI and FU (p = 0.8). In SPCS calculations, 141 from 189 acutely infarcted segments were accurately detected (74.6%), visual evaluation of correlating cine images detected 43.4% infarcts. In FU, 80% infarcted segments (91/114 segments) were detected in SPCS and 51.8% by visual evaluation of correlating short axis cine images (p = 0.01).ConclusionSegmental circumferential strain derived from routinely acquired native cine sequences detects nearly 75% of acute infarcts and 80% of infarcts in subacute follow-up CMR, significantly more than visual evaluation of correlating cine images alone. Acute infarcts may display only subtle impairment of wall motion and no obvious wall thinning, thus SPCS calculation might be helpful for scar detection in patients with acute infarcts, when LGE images are not available.

Quantitative assessment of left ventricular myocardial involvement in patients with connective tissue disease: a 3.0T contrast-enhanced cardiovascular magnetic resonance study

The aim of this study was to evaluate left ventricular (LV) myocardial involvement in connective tissue disease (CTD) patients using multiparemetric imaging derived from cardiovascular magnetic resonance (CMR). CMR was performed on 146 CTD patients (comprising of 74 with idiopathic inflammatory myopathy (IIM) and 72 with non-IIM) and 72 healthy controls and included measures of LV global strains [including peak strain (PS), peak systolic (PSSR) and diastolic strain rate (PDSR)], myocardial perfusion [including upslope, max signal intensity (MaxSI), and time to maximum signal intensity (TTM)], and late gadolinium enhancement (LGE) parameters. Univariable and multivariable linear regression analyses were performed to determine the association between LV deformation and microvascular perfusion, as well as LGE. Our results indicated that CTD patients had decreased global longitudinal PS (GLPS), PSSR, PDSR, and myocardial perfusion (all p < 0.017) compared with normal controls. Non-IIM patients exhibited lower LV global strain and longer TTM than IIM patients. The presence of LGE was independently associated with global radial PS (GRPS: β = − 0.165, p = 0.011) and global circumferential PS (GCPS: β = − 0.122, p = 0.022). TTM was independently correlated with GLPS (β = − 0.156, p = 0.027). GLPS was the best indicator for differentiating CTD patients from normal controls (area under curve of 0.78). This study indicated that CTD patients showed impaired LV global myocardial deformation and microvascular perfusion, and presence of LGE. Cardiac involvement might be more severe in non-IIM patients than in IIM patients. Impaired microvascular perfusion and the presence of LGE were independently associated with LV global deformation.

The adverse impact of coronary artery disease on left ventricle systolic and diastolic function in patients with type 2 diabetes mellitus: a 3.0T CMR study

BackgroundCoronary artery disease (CAD) confers considerable morbidity and mortality in diabetes. However, the role of CAD in additive effect of left ventricular (LV) function has rarely been explored in type 2 diabetes mellitus (T2DM) patients. This study aimed to investigate how CAD affect LV systolic and diastolic function in T2DM patients.Materials and methodsA total of 282 T2DM patients {104 patients with CAD [T2DM (CAD +)] and 178 without [T2DM (CAD −)]} and 83 sex- and age- matched healthy controls underwent cardiac magnetic resonance scanning. LV structure, function, global strains [including systolic peak strain (PS), peak systolic (PSSR) and diastolic strain rate (PDSR) in radial, circumferential and longitudinal directions] and late gadolinium enhancement (LGE) parameters were measured. T2DM (CAD +) patients were divided into two subgroups based on the median of Gensini score (60) which was calculated to assess the severity of CAD. Multivariable linear regression analyses were constructed to investigate the determinants of reduced LV function.ResultsCompared with normal controls, T2DM (CAD −) patients exhibited increased LV end-diastolic and end-systolic volume index and decreased LV global strains, while T2DM(CAD +) patients showed more marked increase and decrease than T2DM(CAD-) and healthy controls, except for longitudinal PDSR (PDSR-L) (all P < 0.017). All of LV global strains demonstrated a progressive decrease from normal controls, through Gensini score ≤ 60, to Gensini score > 60 group, except for PDSR-L (all P < 0.017). CAD was an independent predictor of reduced LV global circumferential PS (GCPS, β = 0.22, p < 0.001), PSSR (PSSR-C, β = 0.17, p = 0.005), PDSR (PDSR-C, β = 0.22, p < 0.001), global radial PS (GRPS, β = 0.19, p = 0.001), and global longitudinal PS (GLPS, β = 0.18, p = 0.003) in T2DM. The Gensini score was associated with decreased GCPS, PSSR-C, PDSR-C, GRPS, and GLPS in T2DM (CAD +) (all p < 0.05).ConclusionCAD has an additive deleterious effect on LV systolic and diastolic function in T2DM patients. Among T2DM (CAD +) patients, the Gensini score is associated with reduced LV contractile and diastolic function.Trial registration Retrospectively registered

Characterization and clinical significance of biventricular mechanics in patients with systemic lupus erythematosus by 3T cardiovascular magnetic resonance tissue tracking.

Detecting impaired left ventricle (LV) or right ventricle (RV) mechanics could aid in fully understanding the process of cardiac involvement in patients with systemic lupus erythematosus (SLE). This study aimed to evaluate biventricular strain parameters derived from cardiac magnetic resonance (CMR) tissue tracking in SLE patients and their association with other clinical variables. A group of 47 SLE patients and 27 healthy controls were enrolled and underwent CMR examination, including cine and late gadolinium enhancement (LGE) imaging. Aside from RV strain parameters in the radial direction, biventricular global peak strain and peak systolic/diastolic global strain rate in radial, circumferential, and longitudinal directions were assessed for each participant. Multivariate linear regression analysis was used to analyze the factors related to the biventricular strain parameters. Receiver operating characteristic (ROC) analysis was used to identify RV dysfunction. Compared with the controls, part of the biventricular strain parameters in the SLE subgroup with preserved ejection fraction (EF) were impaired, which was more significant in the SLE subgroup with reduced EF (all P<0.05). The SLE patients with RV dysfunction (15/47) included patients with LV dysfunction (8/47). The RVEF was associated with impaired LV global peak strain and peak diastolic strain rate in the SLE patients (absolute value of β=0.406-0.715, all P<0.05). The LV LGE in SLE patients (12/47) was associated with LV global longitudinal peak strain and peak diastolic global longitudinal strain rate (β=0.378 and -0.342; all P<0.05). There were independent correlations between pulmonary arterial hypertension and RV global longitudinal peak strain, anti-ribonucleoprotein (RNP) antibody and RV global circumferential peak strain, and pericardial effusion and RV peak diastolic global circumferential strain rate, respectively (β=0.319, 0.359, and -0.285, respectively; all P<0.05). The LV global longitudinal peak strain had greater diagnostic accuracy for RV dysfunction RV dysfunction [area under curve (AUC): 0.933, cut-off value: -13.38%). Biventricular strain parameters derived from CMR are sensitive markers of subclinical ventricular function impairment before EF reduction at an early stage of SLE. Biventricular strain analysis could be considered for inclusion in early cardiac functional assessment in SLE patients, particularly LV global longitudinal peak strain, which might assist in therapeutic decision-making and disease monitoring.

Acute regional changes in myocardial strain may predict ventricular remodelling after myocardial infarction in a large animal model

To identify predictors of left ventricular remodelling (LVR) post-myocardial infarction (MI) and related molecular signatures, a porcine model of closed-chest balloon MI was used along with serial cardiac magnetic resonance imaging (CMRI) up to 5–6 weeks post-MI. Changes in myocardial strain and strain rates were derived from CMRI data. Tissue proteomics was compared between infarcted and non-infarcted territories. Peak values of left ventricular (LV) apical circumferential strain (ACS) changed over time together with peak global circumferential strain (GCS) while peak GLS epicardial strains or strain rates did not change over time. Early LVR post-MI enhanced abundance of 39 proteins in infarcted LV territories, 21 of which correlated with LV equatorial circumferential strain rate. The strongest associations were observed for D-3-phosphoglycerate dehydrogenase (D-3PGDH), cysteine and glycine-rich protein-2, and secreted frizzled-related protein 1 (sFRP1). This study shows that early changes in regional peak ACS persist at 5–6 weeks post-MI, when early LVR is observed along with increased tissue levels of D-3PGDH and sFRP1. More studies are needed to ascertain if the observed increase in tissue levels of D-3PGDH and sFRP1 might be casually involved in the pathogenesis of adverse LV remodelling.

Cardiac involvement in COVID-19 patients: mid-term follow up by cardiovascular magnetic resonance

BackgroundCoronavirus disease 2019 (COVID-19) induces myocardial injury, either direct myocarditis or indirect injury due to systemic inflammatory response. Myocardial involvement has been proved to be one of the primary manifestations of COVID-19 infection, according to laboratory test, autopsy, and cardiovascular magnetic resonance (CMR). However, the middle-term outcome of cardiac involvement after the patients were discharged from the hospital is yet unknown. The present study aimed to evaluate mid-term cardiac sequelae in recovered COVID-19 patients by CMRMethodsA total of 47 recovered COVID-19 patients were prospectively recruited and underwent CMR examination. The CMR protocol consisted of black blood fat-suppressed T2 weighted imaging, T2 star mapping, left ventricle (LV) cine imaging, pre- and post-contrast T1 mapping, and late gadolinium enhancement (LGE). LGE were assessed in mixed both recovered COVID-19 patients and healthy controls. The LV and right ventricle (RV) function and LV mass were assessed and compared with healthy controls.ResultsA total of 44 recovered COVID-19 patients and 31 healthy controls were studied. LGE was found in 13 (30%) of COVID-19 patients. All LGE lesions were located in the mid myocardium and/or sub-epicardium with a scattered distribution. Further analysis showed that LGE-positive patients had significantly decreased LV peak global circumferential strain (GCS), RV peak GCS, RV peak global longitudinal strain (GLS) as compared to non-LGE patients (p < 0.05), while no difference was found between the non-LGE patients and healthy controls.ConclusionMyocardium injury existed in 30% of COVID-19 patients. These patients have depressed LV GCS and peak RV strains at the 3-month follow-up. CMR can monitor the COVID-19-induced myocarditis progression, and CMR strain analysis is a sensitive tool to evaluate the recovery of LV and RV dysfunction.

Changes in right ventricular deformation during hyperoxia versus normoxaemia in patients with stable coronary artery disease and healthy controls

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): Local research funds of the Department of Anaesthesiology and Pain medicine, Bern University Hospital, Inselspital Background During anaesthesia, emergency and critical care treatment, patients with coronary artery disease (CAD) are often exposed to supraphysiologic arterial oxygen tensions. The balance between benefits and risks of hyperoxia (HO) in patients with stable CAD is controversial, with reports about reduced left ventricular contractility or increased morbidity and mortality. Effects of HO on right ventricular (RV) function in CAD are less well described. Advanced cardiovascular magnetic resonance (CMR) feature tracking software allows assessment of myocardial deformation, which may serve as early marker of ventricular dysfunction. In a CMR study we quantified the effect of HO on RV function and deformation in awake healthy participants and CAD patients. Methods Ten healthy participants and 26 patients with stable one- or two-vessel obstructive CAD were included. In a CMR study, a short-axis function stack of both ventricles was obtained first at room air (RA), then during HO induced by breathing oxygen at 10L/min for 5 minutes via a non-rebreathing facemask. RV strain was analysed by a blinded reader who manually traced epicardial and endocardial contours of the RV for determining peak global circumferential strain (RVGCS), time to peak strain, systolic and diastolic strain rate parameters. Results RV ejection fraction did not change with O2 breathing in the healthy control group (RA, 56 ± 12% vs. HO, 55 ± 10%, p = 0.999) nor in the CAD group (RA, 60 ± 8% vs. HO, 60 ± 9%, p = 0.609). RV cardiac index decreased significantly in CAD patients from RA (2.62 ± 0.88 L/min/m2) to HO (2.42 ± 0.77L/min/m2, p = 0.002). The decrease in the control group was not significant (RVCI: RA 3.28 ± 1.29 vs HO 3.04 ± 1.27L/min/m2 p = 0.068). In the healthy control group, RVGCS, time to peak strain, and systolic strain rate did not change significantly with HO (RVGCS: RA, -14.6 ± 3.9% vs. HO, -13.1 ± 4.5%, p = 0.353; time to peak strain: 282 ± 45ms vs. 286 ± 29ms, p = 0.540; and systolic strain rate: -0.85 ± 0.27/s vs. -0.67 ± 0.28, p = 0.055). In CAD patients RVGCS worsened from -14.8 ± 3.3% on RA to -13.9 ± 3.6% at HO (p = 0.040). Time to peak strain became significantly prolonged from 319 ± 40ms on RA to 329 ± 49ms at HO (p = 0.046). This was accompanied by a reduction of systolic strain rate from -0.79 ± 0.27/s to -0.75 ± 0.22/s (p = 0.037). Diastolic strain parameters did not differ significantly between RA and HO in either group. Conclusion In our cohort of CAD patients HO significantly reduced RV cardiac index and impaired systolic deformation as determined by CMR feature tracking. Studies are required in a larger patient cohort with regional analysis and assessment of longitudinal and radial deformation to assess the role of hyperoxia in CAD. Abstract Figure. Change in RV Peak Circumferential Strain

Ventricular strain is compromised outside of the coronary autoregulatory range – assessment by cardiovascular magnetic resonance

Introduction Coronary autoregulation maintains near-constant myocardial blood flow in a range of approximately 60-140 mmHg of mean arterial pressure (MAP). Using oxygenation-sensitive (OS) cardiovascular magnetic resonance (CMR), we showed that myocardial oxygenation is compromised at MAP levels below the lower limit of this range. Above its upper limit we observed luxury perfusion and mild oxygen excess. There is a lack of data exploring the relationship between coronary autoregulation, myocardial oxygenation and ventricular function. CMR feature tracking software allows to quantify myocardial deformation and strain in OS images. Our aim was to explore our data from an animal study for associations between myocardial function, myocardial oxygenation and coronary blood flow (CBF) over a wide range of MAP levels. Methods In ten anaesthetized swine a flow probe was surgically attached to the proximal left anterior descending coronary artery before the animals were placed into a 3 Tesla MRI scanner. Starting from a baseline of 70 mmHg, MAP was varied in steps of 10-15 mmHg using phenylephrine and urapidil, respectively. At each MAP level, OS cine images and CBF readings of the anterior descending coronary artery were obtained, as well as arterial and coronary sinus blood gas samples to determine myocardial oxygen extraction ratio. Using feature tracking-software, strain data were acquired from images by tracing endo- and epicardial contours in end-diastole, from which peak global circumferential strain (GCS) was calculated for both ventricles. The relationships of peak GCS to MAP, CBF and myocardial oxygenation were established. Results We analysed 101 MAP levels, which ranged between 35 and 196 mmHg. Oxygenation as assessed by OS-CMR showed a curvi-linear relationship to MAP, with a steeper decrease below the lower limit of the autoregulatory range and an increase above its upper limit. Peak GCS of both ventricles became progressively impacted when MAP was forced from its baseline (70 mmHg) towards and beyond the lower and upper autoregulatory limit (dashed yellow lines in figure). There was no apparent association between changes of peak GCS and CBF. GCS of left ventricular myocardium decreased linearly with increasing myocardial oxygen extraction ratio (r=0.261, p=0.026), and in a non-linear fashion with decreasing myocardial tissue oxygenation. Discussion In a porcine model with non-diseased hearts, biventricular systolic function becomes compromised when MAP reaches levels either below or above coronary autoregulatory limits. Contractile dysfunction at pressures below the lower limit appears to be caused by myocardial deoxygenation. Conversely, hypertension-induced systolic dysfunction is associated with increased coronary flow and oxygen excess, which points to high afterload rather than O2 demand/supply imbalance as the most likely mechanism. We conclude that in hearts without coronary disease, global strain abnormalities elicited by hypotensive or hypertensive stress also differ in their underlying pathophysiological mechanisms.

Effects of normoxic versus hyperoxic hyperventilation followed by apnea on right ventricular strain in patients with multi-vessel coronary artery disease

Introduction Hypocapnia and hyperoxia are coronary vasoconstrictors, whereas hypercapnia acts as a coronary vasodilator. Prior to anaesthetic induction, patients receive a FiO2 of 1.0 and are asked to take deep breaths. Resulting hyperoxic hypocapnia may be aggravated by excessive manual ventilation. Subsequent apnea during intubation increases paCO2. So far it remains unclear whether and how such rapid blood gas alterations impact right ventricular (RV) function, especially so in the presence of coronary artery disease (CAD). Cardiovascular magnetic resonance (CMR) imaging is useful to assess subtle changes of myocardial function and constitutes the gold standard for RV imaging. The objective of this CMR study is to compare RV function of healthy persons and patients with CAD during a typical hyperventilation-apnea maneuver. Methods Ten healthy participants and 25 patients with stable, well-defined multi-vessel CAD underwent a CMR study. After baseline imaging at room air, subjects hyperventilated for 60 seconds (HV) and then maintained apnea for 30s. Cine images of two ventricular short axis slices were acquired at baseline and from the end of HV throughout the breath-hold. After reequilibration, participants breathed oxygen (10L/min) for 5 minutes via a non-rebreathing mask and repeated the same respiratory maneuver under oxygen inhalation. CMR cine images were analyzed for RV global peak circumferential strain (RVGCS) for each group and condition. Results Healthy participants showed no significant RVGCS changes within or between normoxic or hyperoxic respiratory maneuvres, although HV enhanced strain numerically. CAD patients showed significant attenuation of RVGCS at the end of the hyperoxic HV-apnea sequence (baseline, -13.5±4.7 % vs. hyperoxic apnea, -11.8±4.9 %; p= 0.047), but not after the respective sequence at room air (-13.8±4.1%, p=0.611). In 20% of the CAD patients the hyperoxic HV-apnea sequence attenuated RVGCS by more than 5% from normoxic baseline. The figure shows RVGCS of both groups during the maneuver (more negative numbers representing better systolic contractile function, i.e., circumferential shortening). Discussion At the conclusion of an induced respiratory maneuver, which resembles a hyperoxic anaesthesia induction sequence, awake CAD patients exhibit significant attenuation of RV peak circumferential strain. This response could be haemodynamically relevant during anaesthesia induction in high-risk CAD patients and needs to be investigated further in a scenario of general anaesthesia.

Strain analysis using feature tracking cardiac magnetic resonance (FT-CMR) in the assessment of myocardial viability in chronic ischemic patients.

The purpose of this study is totest the capability of a commercially available feature tracking-cardiac magnetic resonance (FT-CMR) strain analysis software module in differentiating between viable and non-viable myocardium in chronic ischemic patients. Thirty chronic ischemic patients and 10 healthy volunteers were enrolled. Cine images were used for peak circumferential and radial strains quantification using dedicated FT-CMR software. Global strain was compared between patients and controls. In patients, segmental strain was compared in viable and non-viable myocardium determined by late gadolinium enhancement (LGE); and in segments with wall abnormalities. Among 480 myocardial segments analyzed in patients, 76 segments were non-viable on LGE. The mean left ventricular ejection fraction (LVEF) of the patients (87% males, mean age 55 ± 12years) was 40 ± 12% vs. 61 ± 5% for the controls (80% males, mean age 39 ± 11years). Peak global circumferential strain (GCS) and global radial strain (GRS) were significantly impaired in patients compared to controls (-13.89 ± 4.12% vs. -19.84 ± 1.47%), p < 0.001 and (23.11 ± 6.59% vs. 31.72 ± 5.52%), p = 0.001. Segmental circumferential strain (SCS) and segmental radial strain (SRS) were significantly impaired in non-viable compared to viable segments (-9.47 ± 7.26% vs. -14.72 ± 7.5%), p < 0.001 and (15.67 ± 12.11% vs. 24.51 ± 16.22%), p < 0.001. Cut-off points of -9.36% for the SCS (AUC = 0.7, 95% CI = 0.63-0.77) and 19.5% for the SRS (AUC = 0.67, 95%CI = 0.61-0.73) were attained above which the segment is considered viable.SCS was able to discriminate between normokinetic, hypokinetic and akinetic segments (mean = 27.6 ± 17.13%, 18.66 ± 12.88% and 15.24 ± 10.70% respectively, p < 0.001). Circumferential and radial segmental strain analysis by FT-CMR was able to discriminate between viable and non-viable segments of the myocardium defined by LGE and between normokinetic, hypokinetic and akinetic segments, using routinely acquired cine images, and thus can provide a more objective metric for risk stratification in chronic ischemic patients.