Feature-tracking Strain Analysis Research Articles

Machine learning-based interpretation of non-contrast feature tracking strain analysis and T1/T2 mapping for assessing myocardial viability

Assessing myocardial viability is crucial for managing ischemic heart disease. While late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) is the gold standard for viability evaluation, it has limitations, including contraindications in patients with renal dysfunction and lengthy scan times. This study investigates the potential of non-contrast CMR techniques—feature tracking strain analysis and T1/T2 mapping—combined with machine learning (ML) models, as an alternative to LGE-CMR for myocardial viability assessment. A retrospective analysis was conducted on 79 patients with myocardial infarction (MI) 2–4 weeks post-event. Patients with prior ischemia or poor imaging quality were excluded to ensure robust data acquisition. Various ML algorithms were applied to data from LGE-CMR and non-contrast CMR techniques. Random forest (RF) demonstrated the highest predictive accuracy, with area under the curve (AUC) values of 0.89, 0.90, and 0.92 for left anterior descending (LAD), right coronary artery (RCA), and left circumflex (LCX) coronary artery territories, respectively. For the LAD territory, RF, k-nearest neighbors (KNN), and logistic regression were the top performers, while RCA showed the best results from RF, neural networks (NN), and KNN. In the LCX territory, RF, NN, and logistic regression were most effective. The integration of T1/T2 mapping and strain analysis significantly enhanced myocardial viability prediction, positioning these non-contrast techniques as promising alternatives to LGE-CMR. ML models, particularly RF, provided superior diagnostic accuracy across coronary territories. Future studies should validate these findings across diverse populations and clinical settings.

Advanced Myocardial Characterization in Hypertrophic Cardiomyopathy: Feasibility of CMR-based Feature Tracking Strain Analysis

Abstract Aim of the Work This study aimed to evaluate the role of cardiovascular magnetic resonance feature tracking (CMR-FT) using a commercially available software module for analysis of left ventricular strain in hypertrophic cardiomyopathy patients. Patients and Methods A total of 20 HCM patients and 10 controls were studied. All patients were subjected to detailed clinical history taking and CMRI. Left ventricular global longitudinal, circumferential and radial strains were analyzed as well as segmental longitudinal and circumferential strains. Results LV mass in the HCM group was significantly higher than that in the control group (p < 0.001). No statistical difference was found in ejection fraction (p = 0.074). Global circumferential strain (GCS) global longitudinal strain (GLS), segmental longitudinal strain (SLS) and segmental circumferential strain (SCS) in the HCM group were all significantly lower than the correlated parameters in the control group (p < 0.001, respectively). Global radial strain (GRS) in the HCM group was significantly higher than the control group (p = 0.002). Additionally, SLS & SCS in the HCM group were both significantly lower, before global strain affection (p < 0.001). Conclusion CMR-FT is a promising approach in analyzing impairment of global and segmental myocardium deformation in Egyptian patients with hypertrophic cardiomyopathy, non-invasively and quantitatively.

Left atrial and left ventricular strain in feature-tracking cardiac magnetic resonance for predicting patients at high risk of sudden cardiac death in hypertrophic cardiomyopathy.

Sudden cardiac death (SCD) represents the most severe complication of hypertrophic cardiomyopathy (HCM). The risk stratification of SCD in patients with HCM remains a subject of ongoing debate, and the utility of left atrial (LA) and left ventricular (LV) myocardial strain for risk stratification of also SCD remains uncertain. Through use of feature-tracking cardiac magnetic resonance (FT-CMR), this study aimed to investigate the attenuation of LA and LV strain in HCM and to assess their predictive value in SCD. This retrospective and cross-sectional study included patients with HCM who underwent 3.0 T cardiac magnetic resonance (CMR) at a single institution. Feature-tracking strain analysis was conducted to obtain the strain rate (SR) and LV strain and to evaluate LV function. LA strain was measured during different functional phases including left atrial reservoir strain (LARS), LA conduit strain (LACS), and LA booster strain. All patients were categorized into high- and low-risk groups for SCD as defined by the 2020 American Heart Association/American College HCM implantable cardioverter defibrillator class of recommendation algorithm. Comparison between the two groups was conducted using the independent samples t test and the nonparametric rank sum test. Multivariate logistic regression analysis was performed to further identify the factors influencing SCD risk in HCM. Compared with those in the low-risk group, patients in the high-risk group had lower left ventricular ejection fraction (LVEF), LV stroke volume index (LVSVI), and LA stroke volume index (LASVI) but a higher LV end-systolic volume index (LVESVI), LV maximum wall thickness, and late gadolinium enhancement (LGE) (P<0.001). LV strain, SR, and LA strain all showed significant differences between the high- and low-risk groups (LARS: P=0.04; LACS: P=0.02; all other P values <0.001). The LV global circumferential strain (LVGCS) had a strong negative correlation with LVEF in patients with HCM (r=-0.76; P<0.001). Multivariate analysis showed that LV global radial strain (LVGRS) and LARS could be used for categorizing the patients into the high-risk group [LVGRS: odds ratio (OR) =0.69; 95% confidence interval (CI): 0.55-0.87, P<0.001; LARS: OR =1.39; 95% CI: 1.02-1.90, P=0.03]. The combined LVGRS-LARS model exhibited a superior diagnostic value for high risk of SCD [area under the curve (AUC) =0.95; 95% CI: 0.90-1.00; P<0.001] compared to LARS alone (AUC =0.63; 95% CI: 0.51-0.76; P=0.04). LA and LV strain measured by FT-CMR can accurately identify those patients with HCM at a high risk of SCD. This approach may prove considerably value in guiding early therapeutic intervention with implantable cardioverter-defibrillators (ICDs) to prevent adverse clinical outcomes.

Dobutamine Stress Cardiovascular Magnetic Resonance Derived 2-Dimension Feature Tracking Strain Analysis in Pediatric Population with Anomalous Aortic Origin of Right Coronary Artery.

Anomalous aortic origin of right coronary artery (AAORCA) is associated with myocardial ischemia and sudden cardiac arrest/death. Risk stratification remains challenging and relies upon provocative test results. This study describes the utility of dobutamine stress cardiovascular magnetic resonance (DSCMR) and potential benefit of strain analysis in children with AAORCA. All patients less than 21years of age with AAORCA who underwent DSCMR between July 2018 and December 2022 were included. Visual wall motion abnormalities (VWMA) at rest and during protocolized increments of dobutamine infusion were assessed. Regional and global left ventricular circumferential (GCS) and radial (GRS) strain using 2-dimension Feature tracking (2D-FT) analysis (cvi42, Circle Cardiovascular Imaging Inc.) were calculated at rest and peak response. Of the total 54 DSCMR studies performed in 51 children with median age (IQR) of 13.5 (11-15)years, FT analysis was reliably performed in 52 (96%) studies. None had VWMA. The absolute change in GCS and GRS from rest to peak dobutamine stress was 4% (1-6%) and 11% (4-18%), respectively. There was no significant difference in GCS and GRS in patients with exertional symptoms vs no/non-exertional symptoms as well as between those considered to be high-risk vs low-risk anatomical features. DSCMR-derived 2D-FT strain analysis is feasible to assess myocardial deformation in children with AAORCA and may enhance this method of provocative testing. Although there were no statically significant differences in GCS and GRS values between high and low-risk subgroups, the absolute change in GCS between rest and peak stress is diminished when compared to normal adult reports.

Kiosk 11R-FB-08 - Left and Right Atrial Feature Tracking Strain Analysis in Highly Trained Athletes and Healthy Controls: The Role of Sex and Training Load

Kiosk 11R-FB-08 - Left and Right Atrial Feature Tracking Strain Analysis in Highly Trained Athletes and Healthy Controls: The Role of Sex and Training Load

Functional significance of myocardial activity at 18F-FAPI PET/CT in hypertrophic cardiomyopathy identified by cardiac magnetic resonance feature-tracking strain analysis.

This study aimed to evaluate the functional significance of 18F-labeled fibroblast activation protein inhibitor (18F-FAPI) activity in hypertrophic cardiomyopathy (HCM) by comparison with cardiac magnetic resonance feature-tracking (CMR-FT) strain analysis. A total of 49 HCM patients were included in this study. Two independent control groups of healthy participants with a matched age and sex to the HCM patients were also enrolled. Left ventricular (LV) 18F-FAPI activity was analyzed for extent (FAPI%) and intensity (maximum target-to-background ratio, TBRmax). The CMR tissue characterization parameters of the LV included late gadolinium enhancement, native T1 value, and extracellular volume fraction. LV strain analysis was performed in radial, circumferential, and longitudinal peak strains (PS). Intense LV myocardial 18F-FAPI uptake was observed in HCM patients, whereas no obvious uptake was detected in healthy participants (median TBRmax, 9.1 vs. 1.2, p < 0.001). The strain parameters of HCM patients, compared with healthy participants, were significantly impaired (mean radial PS, 23.5 vs. 36.0, mean circumferential PS, -14.5 vs. -20.0, and mean longitudinal PS, -9.9 vs. -16.0, all p < 0.001). At segmental levels, there was a moderate correlation between 18F-FAPI activity and strain parameters. The number of positive 18F-FAPI uptake segments (n = 653) was higher than that of hypertrophic segments (n = 190) and positive CMR tissue characterization segments (n = 525) (all p < 0.001). In segments with negative CMR tissue characterization findings, the strain capacity of positive 18F-FAPI uptake segments was lower than that of negative 18F-FAPI uptake segments (median radial PS, 30.5 vs. 36.1, p = 0.026 and median circumferential PS, -18.4 vs. -19.7, p = 0.041). 18F-FAPI imaging can partially reflect the potential strain reduction in HCM patients. 18F-FAPI imaging detects more involved myocardium than CMR tissue characterization techniques, and the additionally identified myocardium has impaired strain capacity.

Reduced myocardial strain of interventricular septum among male amateur marathon runners: a cardiac magnetic resonance study

ObjectivesTo analyze the long-term effect of multiple marathons on cardiac structure and function in amateur marathon runners compared with healthy controls. DesignCross-sectional study using male amateur marathon runners (n = 32) and age-matched cohort of male healthy controls (n = 12). MethodsA total of 32 male amateur marathon runners (age 44 ± 7 years) and 12 male healthy controls (age 42 ± 8 years) underwent cardiac magnetic resonance (CMR). The relevant parameters of cardiac structure and function were studied employing feature-tracking strain analysis. ResultsAmateur marathon runners showed lower heart rates, body mass index and body surface area. The left ventricular (LV) mass index, LV end-diastolic volume index and right ventricular end-systolic volume index were significantly higher in amateur marathon runners compared with healthy controls. Furthermore, walls of interventricular septum (IVS) in amateur marathon runners were thicker than healthy controls. There was no significant difference between two groups in the global myocardial strain (MS) in LV. However, the segmental radial and circumferential strains of the LV were lower in amateur marathon runners compared to healthy controls, specifically in the 8th and 9th segments. Finally, we also found as the total running intensity increased, so did global longitudinal strain. ConclusionsWe reported higher wall thickness and lower regional radial and circumferential strain in the IVS region in amateur marathon runners, suggesting that prolonged and high-intensity exercise may cause cardiac remodeling. Further studies are needed to investigate whether this is an adaptive or maladaptive change in amateur marathon runners.

Localized strain characterization of cardiomyopathy in Duchenne muscular dystrophy using novel 4D kinematic analysis of cine cardiovascular magnetic resonance

BackgroundCardiomyopathy (CMP) is the most common cause of mortality in Duchenne muscular dystrophy (DMD), though the age of onset and clinical progression vary. We applied a novel 4D (3D + time) strain analysis method using cine cardiovascular magnetic resonance (CMR) imaging data to determine if localized strain metrics derived from 4D image analysis would be sensitive and specific for characterizing DMD CMP. MethodsWe analyzed short-axis cine CMR image stacks from 43 DMD patients (median age: 12.23 yrs [10.6–16.5]; [interquartile range]) and 25 male healthy controls (median age: 16.2 yrs [13.3–20.7]). A subset of 25 male DMD patients age-matched to the controls (median age: 15.7 yrs [14.0-17.8]) was used for comparative metrics. CMR images were compiled into 4D sequences for feature-tracking strain analysis using custom-built software. Unpaired t-test and receiver operator characteristic area under the curve (AUC) analysis were used to determine statistical significance. Spearman's rho was used to determine correlation. ResultsDMD patients had a range of CMP severity: 15 (35% of total) had left ventricular ejection fraction (LVEF) > 55% with no findings of myocardial late gadolinium enhancement (LGE), 15 (35%) had findings of LGE with LVEF > 55% and 13 (30%) had LGE with LVEF < 55%. The magnitude of the peak basal circumferential strain, basal radial strain, and basal surface area strain were all significantly decreased in DMD patients relative to healthy controls (p < 0.001) with AUC values of 0.80, 0.89, and 0.84 respectively for peak strain and 0.96, 0.91, and 0.98 respectively for systolic strain rate. Peak basal radial strain, basal radial systolic strain rate, and basal circumferential systolic strain rate magnitude values were also significantly decreased in mild CMP (No LGE, LVEF > 55%) compared to a healthy control group (p< 0.001 for all). Surface area strain significantly correlated with LVEF and extracellular volume (ECV) respectively in the basal (rho = − 0.45, 0.40), mid (rho = − 0.46, 0.46), and apical (rho = − 0.42, 0.47) regions. ConclusionStrain analysis of 3D cine CMR images in DMD CMP patients generates localized kinematic parameters that strongly differentiate disease from control and correlate with LVEF and ECV.

Subclinical cardiac involvement in student athletes after COVID-19 infection - Evaluation using feature tracking cardiac MRI strain analysis

ObjectivesTo evaluate subclinical cardiac dysfunction in student athletes after COVID-19 infection using feature tracking cardiac MRI strain analysis. MethodsStudent athletes with history of COVID-19 infection underwent cardiac MRI as part of screening before return to competitive play. Subjects were enrolled if they had no or mild symptoms, normal cardiac MRI findings with no imaging evidence of myocarditis. Feature tracking strain analysis was performed using short and long axis cine MRI images of athletes and a separate cohort of healthy controls. Differences between the cardiac strain parameters were statistically analyzed by Mann-Whitney U test. ResultsThe study cohort included 122 athletes (49 females, mean age 20 years ± 1.5 standard deviations) who had a history of COVID-19, and 35 healthy controls (24 females, mean age 34 years ± 18 standard deviations). COVID-19 positive athletes had normal physiologic cardiac adaptations, including significantly higher left and right ventricle end-diastolic volumes (p = 0.00001) when compared to healthy controls. There was no significant difference between biventricular ejection fraction between athletes and control subjects (p > 0.05). Cardiac MRI parameters, including left ventricle global longitudinal strain (LV-GLS), global circumferential strain (LV-GCS), and global radial strain (LV-GRS) values were normal but slightly lower in athletes compared to controls. LV-GCS and LV-GRS were significantly lower in athletes compared to controls (p = 0.007 and p = 0.005 respectively), but there was no significant difference for LV-GLS (p = 0.088). ConclusionIn this study of 122 athletes, there was no evidence of subclinical myocardial alterations following recovery from COVID-19 found on cardiac MRI strain analysis. When compared to healthy controls, the competitive athletes had higher end-diastolic volume indices and reduced, albeit normal, strain values of LV-GLS, LV-GCS, and LV-GRS.

Feature tracking strain analysis detects the onset of regional diastolic dysfunction in territories with acute myocardial injury induced by transthoracic electrical interventions

Electric interventions are used to terminate arrhythmia. However, myocardial injury from the electrical intervention can follow unique pathways and it is unknown how this affects regional ventricular function. This study investigated the impact of transthoracic electrical shocks on systolic and diastolic myocardial deformation. Ten healthy anaesthetized female swine received five transthoracic shocks (5 × 200 J) and six controls underwent a cardiovascular magnetic resonance exam prior to and 5 h after the intervention. Serial transthoracic shocks led to a global reduction in both left (LV, − 15.6 ± 3.3% to − 13.0 ± 3.6%, p < 0.01) and right ventricular (RV, − 16.1 ± 2.3% to − 12.8 ± 4.2%, p = 0.03) peak circumferential strain as a marker of systolic function and to a decrease in LV early diastolic strain rate (1.19 ± 0.35/s to 0.95 ± 0.37/s, p = 0.02), assessed by feature tracking analysis. The extent of myocardial edema (ΔT1) was related to an aggravation of regional LV and RV diastolic dysfunction, whereas only RV systolic function was regionally associated with an increase in T1. In conclusion, serial transthoracic shocks in a healthy swine model attenuate biventricular systolic function, but it is the acute development of regional diastolic dysfunction that is associated with the onset of colocalized myocardial edema.

The role of cardiac magnetic resonance-based feature-tracking strain analysis in the differential diagnosis and prognostic assessment of patients with left ventricular hypertrophy

Abstract Background Cardiac magnetic resonance (CMR) examinations have an essential role in the diagnosis of myocardial diseases with left ventricular (LV) hypertrophy; however, limited data are available from CMR-based feature-tracking strain analysis in this patient population. The aim of our study was to investigate the differential diagnostic and prognostic importance of feature-tracking strain analysis in patients with LV hypertrophy caused by myocardial disease. Methods We investigated 404 patients who underwent CMR examination and were diagnosed with myocardial disease causing LV hypertrophy. Hypertrophic cardiomyopathy (HCM) was detected in 330 patients, cardiac amyloidosis (CA) in 46 patients, Fabry disease (FD) in 12 patients, and endomyocardial fibrosis (EMF) in 16 patients. LV strain analysis was performed with feature-tracking. Global longitudinal (GLS), circumferential (GCS) and radial (GRS) LV strain parameters were measured. Strain values for the six basal, six midventricular, and five apical segments were averaged to obtain regional longitudinal and circumferential strain values (basal LS, midventricular LS, apical LS, basal CS, midventricular CS, apical CS). The apex-to-base regional LS and CS ratios were calculated as apical LS/basal LS and apical CS/basal CS, respectively. To assess global dyssynchrony, mechanical dispersion (MD) was measured. The all-cause mortality of the patients was analyzed. Results In the differentiation of CA from HCM, GLS had the highest sensitivity with a cutoff of more than −23%, and basal LS and basal CS had the highest specificity with a cutoff of more than −16% and −38%, respectively (p&amp;lt;0.001). FD patients had the lowest longitudinal and circumferential MD values, meaning that compared to that of other patients with LV hypertrophy, global dyssynchrony is least pronounced in this patient population (p&amp;lt;0.01). EMF patients had impaired global and regional CS and the lowest apex-to-base CS and LS ratios. CA patients had the highest apex-to-base CS and LS ratios, suggestive of apical sparing (p&amp;lt;0.001). CA patients had the worst prognosis; the significant independent predictors of mortality were a diagnosis of CA, the LV stroke volume index and basal LS (p&amp;lt;0.01). Conclusions Myocardial diseases with left ventricular hypertrophy have remarkable differences in CMR-based strain characteristics which can be helpful in the differential diagnosis and provides incremental information on adverse outcomes. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Development and Innovation Fund of Hungary, Ministry for Innovation and Technology in Hungary

Left atrial strain at CMR is a strong independent prognostic predictor in DCM, superior to LV-GLS, LVEF and LAVI, and incremental to LGE

Abstract Background The left atrium (LA) is an early sensor of left ventricular (LV) dysfunction. LA size and new-onset atrial fibrillation (AF) are associated with an increased risk of mortality and heart failure (HF) progression in patients with dilated cardiomyopathy (DCM). Whether abnormal LA strain measured at cardiac magnetic resonance (CMR) – a new technology to study atrial function – may predict overall outcome in DCM – either or not leading to new onset AF – remains completely unknown. Purpose To determine the prognostic value of CMR derived LA strain in DCM patients. Methods A total of 488 DCM patients (age 54 [46–62] years, 61% male) undergoing CMR were prospectively enrolled in the Maastricht Cardiomyopathy Registry between 2004 and 2018. Outcome consisted of the combination of sudden or cardiac death, HF hospitalization or life-threatening arrhythmias. LA reservoir (passive LA filling), conduit (passive LV filling), and booster strain (active LV filling) were measured using feature tracking strain analysis of the 2- and 4-chamber long-axis cines (Figure 1). Given the non-linearity of continuous variables, cubic spline analysis was performed to dichotomize. Results Seventy out of 488 DCM patients (14%) reached the endpoint (follow-up 6 [4–9] years). Age, NYHA class ≥3, late gadolinium enhancement (LGE) presence, LV ejection fraction (EF), LA volume index (LAVI), LV global longitudinal strain (GLS), and LA reservoir and conduit strain were univariably associated with worse outcome (all p-values &amp;lt;0.02). LA conduit strain was superior to reservoir strain to predict outcome. LA conduit strain, NYHA class ≥3 and LGE remained associated in the multivariable model (Figure 2A), while age, NTproBNP, LVEF, LA ejection fraction, LAVI and LV-GLS did not. Adding LA conduit strain to NYHA class and LGE significantly improved the calibration, accuracy, and reclassification of the prediction model (p&amp;lt;0.05). In patients without known AF and sinus rhythm (n=425) during CMR, 10% developed new-onset AF (paroxysmal or persistent) at long-term. Higher age, male sex, NYHA class ≥3, higher LAVI and impaired booster strain were all univariably associated with new-onset AF. Age and impaired booster strain remained as independent predictors of new-onset AF in the multivariable analysis (Figure 2B). Conclusions LA conduit strain on CMR is a strong independent prognostic predictor in DCM, superior to LV-GLS, LVEF and LAVI, and incremental to LGE. In addition, LA booster strain is an independent predictor of new-onset AF. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Netherlands Cardiovascular Research Initiative, an initiative with support of the Dutch Heart Foundation

CMR derived left ventricular intraventricular pressure gradients identify different patterns associated with prognosis in patients with dilated cardiomyopathy

Abstract Introduction The direction of blood flow in the left ventricle (LV) is determined by intraventricular pressure gradients (IVPGs) between apex and base, which are altered when cardiac function declines. New cardiac magnetic resonance (CMR) post-processing software enables estimating LV-IVPGs. To date, the prognostic value of CMR derived IVPGs in patients with dilated cardiomyopathy (DCM) remains unknown. Methods DCM patients from the Maastricht Cardiomyopathy Registry, who underwent a CMR, were included. The software estimates the LV-IVPGs (between apex and base) by using the myocardial movement and velocity of a reconstructed 3D-LV model (derived from feature-tracking strain analysis of 2-, 3- and 4-chamber cine images). The primary outcome was a combined endpoint of heart failure (HF) hospitalisations, life-threatening arrhythmias and (sudden) cardiac death. Results In total, 447 DCM patients were included (age 55 interquartile range [46–63] years; 60% male). During a median follow-up of 6 [4–9] years, 66 patients (15%) reached the primary endpoint. In 168 patients (38%), a temporary pressure reversal from base-apex to apex-base during the systolic-diastolic transition was observed (figure). After correction for covariates that were univariably associated with outcome (p&amp;lt;0.100, age, NYHA-class≥3, and left atrial (LA) conduit strain), flow reversal from base-apex to apex-base in the diastole was independently associated with outcome in the total cohort (HR 2.91, 95%-Confidence interval (95%-CI) [1.16–7.32], p=0.023; Table). In patients without pressure reversal (N=279) in the systolic-diastolic transition, IVPG during the total cardiac cycle (HR 0.88 [0.81–0.96], p=0.003), the systolic ejection force (HR 0.92 [0.87–0.97], p=0.003), and the E-wave decelerative force “C” (passive diastolic filling, HR 0.85 [0.74–0.97], p=0.013) were predictors of outcome, independent of other covariates (age, sex, NYHA class ≥3, LV ejection fraction, late gadolinium enhancement, LV longitudinal strain, LA volume index and LA conduit strain, table). Conclusion CMR-derived LV-IVPG analysis showed pressure reversal in the systolic-diastolic transition in one-third of DCM patients, and flow reversal was an independent predictor of worse outcome in these patients. In patients without this pressure reversal, LV-IVPG during the total cardiac cyle, the systolic ejection force, and the E-wave decelerative force were predictors of outcome, independent of all evauluated clinical and imaging parameters. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Netherlands Cardiovascular Research Initiative (initiative with support of the Dutch Heart Foundation) and CVON (She-PREDICTS, grant 2017-21 &amp; CVON-DCVA Double Dosis 2021)

Use of cardiac magnetic resonance imaging and cardiac magnetic resonance feature-tracking strain analysis to characterize and differentiate aortic annular strain patterns in aortic valve regurgitation versus normal aortic valves.

Understanding the aortic annulus is important for obtaining reproducible and durable aortic valve (AV) repair and allowing advances for transcatheter AV replacement treatment of aortic regurgitation (AR). Significant limitations exist when using echocardiography and computed tomography-based imaging with feature tracking at the aortic annulus. Cardiac magnetic resonance is used to obtain regional longitudinal strain and can be modified to obtain circumferential annular strain at the fibrous and muscular portions of the AV annulus. Holst et al. use a novel method to characterize and prove that adverse annular deformation occurs at the muscular portion of the AV annulus in patients with AR. In their study, cardiovascular magnetic resonance (CMR) imaging and CMR feature-tracking strain analysis are used to characterize aortic annular regional longitudinal strain (RLS) in humans. The authors convincing show that the direction of muscular annular deformation in patients with AR is opposite to the direction of muscular annular deformation in patients with normal Avs, (median RLS: 4.18% in patients with severe AR vs. -10.41% in well-functioning AVs, p = .024; at RLS muscular annulus). The direction of muscular annular deformation in patients with AR is opposite to the direction of muscular annular deformation in patients with normal AVs. This information will have impactful physiological relevance for surgical and percutaneous treatment of aortic valve pathology.

MR -specific characteristics of left ventricular noncompaction and dilated cardiomyopathy

BackgroundThe differentiation of dilated cardiomyopathy (DCM) and left ventricular noncompaction (LVNC) is a recurring issue during cardiac imaging processes; thus, we aimed to compare the left ventricular (LV) cardiac MRI characteristics of these patients. MethodsThirty-one nonischemic DCM patients, 42 LVNC patients with reduced ejection fraction and 42 healthy controls were included in this retrospective study. LV volumetric, functional and myocardial mass parameters were measured with a threshold-based technique, while global and segmental strain values and rotational patterns were analyzed with feature-tracking strain analysis. ResultsOf the LV volumetric and myocardial mass parameters, only the trabeculated and papillary muscle mass (TPMi) values differed significantly between the patient groups and were higher in the LVNC group (DCM vs LVNC: 43.2 ± 8.9 vs 51.6 ± 13.6 g/m2, p < 0.002). The global longitudinal and circumferential strains were similar between the patient groups and significantly worse than those of the controls. In comparing the segmental strains between the patient groups, only the circumferential apical strain was significantly lower in the LVNC group (DCM vs LVNC: −30.5 ± 13.5 vs −24.5 ± 12.0%, p < 0.05). There was no difference in the rotational pattern between the patient groups, and both healthy and patient populations showed heterogeneous rotational patterns. ConclusionsDespite the similarities between DCM and LVNC in volumetric, global strain parameters, and rotational patterns, we found some differences between the patient groups, as the TPMi was higher and the apical circumferential strains were significantly lower in LVNC. These minor alterations might be due to the morphological characteristics of LVNC with a trabeculated apical region.

Impact of myocardial injury on regional left ventricular function in the course of acute myocarditis with preserved ejection fraction: insights from segmental feature tracking strain analysis using cine cardiac MRI

The aim of this study was to provide insights into myocardial adaptation over time in myocyte injury caused by acute myocarditis with preserved ejection fraction. The effect of myocardial injury, as defined by the presence of late gadolinium enhancement (LGE), on the change of left ventricular (LV) segmental strain parameters was evaluated in a longitudinal analysis. Patients with a first episode of acute myocarditis were enrolled retrospectively. Peak radial (PRS), longitudinal (PLS) and circumferential (PCS) LV segmental strain values at baseline and at follow-up were computed using feature tracking cine cardiac magnetic resonance imaging. The change of segmental strain values in LGE positive (LGE+) and LGE negative (LGE−) segments was compared over a course of 89 ± 20 days. In 24 patients, 100 LGE+ segments and 284 LGE− segments were analysed. Between LGE+ and LGE− segments, significant differences were found for the change of segmental PCS (p < 0.001) and segmental PRS (p = 0.006). LGE + segments showed an increase in contractility, indicating recovery, and LGE− segments showed a decrease in contractility, indicating normalisation after a hypercontractile state or impairment of an initially normal contracting segment. No significant difference between LGE+ and LGE− segments was found for the change in segmental PLS. In the course of acute myocarditis with preserved ejection fraction, regional myocardial function adapts inversely in segments with and without LGE. As these effects seem to counterbalance each other, global functional parameters might be of limited use in monitoring functional recovery of these patients.

J wave syndromes in patients with spinal and bulbar muscular atrophy

BackgroundMales with X-linked recessive spinobulbar muscular atrophy (SBMA) are reported to die suddenly and a Brugada electrocardiography (ECG) pattern may be present. A hallmark of this pattern is the presence of ST segment elevations in right precordial leads associated with an increased risk of sudden cardiac death.ObjectiveWe aimed to detect subtle myocardial abnormalities using ECG and cardiovascular magnetic resonance imaging (CMR) in patients with SBMA.Methods30 SBMA patients (55.7 ± 11.9 years) and 11 healthy male controls underwent 12-lead ECGs were recorded using conventional and modified chest leads. CMR included feature-tracking strain analysis, late gadolinium enhancement and native T1 and T2 mapping.ResultsTestosterone levels were increased in 6/29 patients. Abnormal ECGs were recorded in 70%, consisting of a Brugada ECG pattern, early repolarization or fragmented QRS. Despite normal left ventricular ejection fraction (66 ± 5%), SBMA patients exhibited more often left ventricular hypertrophy as compared to controls (34.5% vs 20%). End-diastolic volumes were smaller in SBMA patients (left ventricular volume index 61.7 ± 14.7 ml/m2 vs. 79.1 ± 15.5 ml/m2; right ventricular volume index 64.4 ± 16.4 ml/m2 vs. 75.3 ± 17.5 ml/m2). Tissue characterization with T1-mapping revealed diffuse myocardial fibrosis in SBMA patients (73.9% vs. 9.1%, device-specific threshold for T1: 1030 ms).ConclusionSBMA patients show abnormal ECGs and structural abnormalities, which may explain an increased risk of sudden death. These findings underline the importance of ECG screening, measurement of testosterone levels and potentially CMR imaging to assess cardiac risk factors.

MR -specific characteristics of left ventricular noncompaction and dilated cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Thematic Excellence Programme (Tématerületi Kiválósági Program, 2020-4.1.1.-TKP2020) of the Ministry for Innovation and Technology in Hungary within the framework of the Therapeutic Development and Bioimaging Programs of Semmelweis University Development of Scientific Workshops of Medical, Health Sciences and Pharmaceutical Edication (Project identification number: EFOP- 3.6.3-VEKOP-16- 2017-00009) Project no. NVKP_16-1–2016-0017 (’National Heart Program’) has been implemented with the support provided from the National Research, Development and Innovation Fund of Hungary, financed under the NVKP_16 funding scheme. The research was supported by the Ministry of Innovation and Technology NRDI Office within the framework of the Artificial Intelligence National Laboratory Program. The differentiation of dilated cardiomyopathy (DCM) and left ventricular noncompaction (LVNC) is a recurring issue during cardiac imaging processes; thus, we aimed to compare the left ventricular (LV) cardiac MRI (CMR) characteristics of DCM and LVNC patients. Thirty-one nonischemic DCM patients, 42 LVNC patients with reduced EF and 42 healthy controls were included in this retrospective study. The LV volumetric, functional and myocardial mass parameters were measured with a threshold-based technique, while global and segmental strain values and rotational patterns were analyzed with feature-tracking strain analysis. Of the LV volumetric and myocardial mass parameters, only the trabeculated and papillary muscle mass (TPMi) values differed significantly between the patient groups and were higher in the LVNC group compared to DCM (DCM vs LVNC: 43.2 ± 8.9 vs 51.6 ± 13.6 g/m2, p &amp;lt; 0.002). The global longitudinal and circumferential strains were similar between the patient groups and significantly worse than those of the controls. In comparing the segmental strain values between the patient groups, only the circumferential apical strain was significantly lower in the LVNC group (DCM vs LVNC: -30.5 ± 13.5 vs -24.5 ± 12.0%, p &amp;lt; 0.05). There was no difference in the rotational pattern between the patient groups, and both the healthy and patient populations showed heterogeneous rotational patterns. Despite the similarities of DCM and LVNC in volumetric, global strain parameters, and rotational patterns, we found some morphological and functional differences between the patient groups. These minor alterations might be due to the morphological characteristics of LVNC with a trabeculated apical region.

Associations of Infarct Size and Regional Myocardial Function Examined by Cardiac Magnetic Resonance Feature Tracking Strain Analysis with the Infarct Location in Patients with Acute ST-Segment Elevation Myocardial Infarction

ObjectiveTo quantitatively evaluate the associations of infarct size, regional myocardial function examined by cardiac magnetic resonance feature tracking (CMR-FT) strain analysis with infarct location in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention. MethodsCardiac magnetic resonance images were retrospectively analyzed in 95 consecutive STEMI patients with successful reperfusion. The patients were divided into the anterior wall myocardial infarction (AWMI) and nonanterior wall myocardial infarction (NAWMI) groups. Infarct characteristics were assessed by late gadolinium enhancement. Global and regional strains and associated strain rates in the radial, circumferential and longitudinal directions were assessed by CMR-FT based on standard cine images. The associations of infarct size, regional myocardial function examined by CMR-FT strain analysis with infarct location in STEMI patients were evaluated by the Spearman or Pearson method. ResultsThere were 44 patients in the AWMI group and 51 in the NAWMI group. The extent of left ventricular enhanced mass was significantly larger in patients with AWMI compared with the NAWMI group (24.47+11.89, 21.06+12.08 %LV; t = 3.928, P = 0.008). In infarct zone analysis, strains in the radial, circumferential and longitudinal directions were remarkably declined in the AWMI group compared with the NAWMI group (z = -20.873, -20.918, -10.357, all P < 0.001). The volume (end-systolic volume index), total enhanced mass and extent of enhanced mass of the left ventricular were correlated best with infarct zone strain in the AWMI group (all P < 0.001). ConclusionIn STEMI patients treated by percutaneous coronary intervention, myocardial damage is more extensive and regional myocardial function in the infarct zone is lower in the AWMI group compared with the NAWMI group.

Effects of BPA on right ventricular mechanical dysfunction in patients with inoperable CTEPH – A cardiac magnetic resonance study

PurposeThe aim of this study was to assess effects of balloon pulmonary angioplasty (BPA) on right ventricular (RV) mechanical dysfunction in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) via MRI. MethodMRI at 1.5 Tesla and right heart catheterization were performed before and 6 months after BPA in 30 CTEPH patients (mean age 63.4 ± 10.6 years; 17 female). Feature-tracking strain analysis, including global longitudinal (GLS), circumferential (GCS), and radial (GRS) strain, was performed and compared with right ventricular function, myocardial remodelling (assessed by native T1 times), and pulmonary haemodynamics (mean pulmonary arterial pressure and pulmonary vascular resistance). ResultsRVEF (35.9% to 48.4%) increased and mPAP (42.1 mmHg to 33.1 mmHg) and PVR (551.8 to 377.7 dyn∙s/cm5) decreased after BPA (all p < 0.0001). Moreover, RV strain increased (GLS −19.9 to −24.0%, p = 0.0003; GCS −9.4 to −11.0%, p = 0.0022; GRS 38.2 to 50.7%, p = 0.001) and septal native area-adjusted T1 time (AA-T1) decreased (1019.4 to 988.7 ms, p < 0.0001). GLS revealed the best correlations with RVEF (before BPA r = -0.75; after BPA r = -0.54), mPAP (r = 0.36; r = 0.52), PVR (r = 0.49; r = 0.48), and AA-T1 (r = 0.44; 0.19). ConclusionRV mechanical dysfunction, pulmonary haemodynamics, and myocardial remodelling are markedly improved by BPA. Moreover, RV strain values showed good correlations with RV function, pulmonary haemodynamics, and myocardial remodelling. Therefore, strain analysis might provide new insights regarding therapy outcome, monitoring, and prognosis.