Myocardial Tissue Characterization Research Articles

First-in-human trial of atrial fibrillation ablation using real time tissue optical assessment to predict pulsed field lesion durability.

Loss of bipolar electrograms immediately after pulsed field ablation (PFA) makes lesion durability assessment challenging. The aim of this trial (NCT06700226) was to evaluate a novel ablation system that can optically predict lesion durability by detecting structural changes in the tissue during ablation. Patients with paroxysmal atrial fibrillation underwent pulmonary vein isolation (PVI) using PFA (AblaView®, MedLumics). Using polarization sensitive optical coherence reflectometry (PS-OCR), reflective characteristics of myocardial tissue and visualization of real-time contrast between healthy tissue and ablated tissue using a drop in tissue birefringence (BiR) was assessed. Wide antral PVI was performed using single point irrigated PFA (unipolar, 1800V, 3 trains, 21sec). Remapping was performed at 3 months. Primary efficacy outcome was the ability of PS-OCR to predict lesion durability at 3-month remapping. Serious adverse events were recorded. Ten patients were included. In total, 38/40 PVs could be isolated with the system. The mean drop of BiR was 17.3±11.5%. Dragging across the ablation lines showed a persistent drop in BiR. During the remap procedures (9/10 patients), 15 PVs (41.7%) were found to be electrically reconnected. The mean loss of BiR during the index ablation for durable lesions was 20.9%, while only 10.1% BiR loss was observed during the index ablation for reconnected areas (p<0.001). None of the points with ≥17% loss of birefringence was found to be reconnected. This first in human study supports the use of real-time drop in tissue BiR for lesion assessment during PFA delivery and its procedural safety.

Cardiac Magnetic Resonance Imaging in Diagnostics and Cardiovascular Risk Assessment.

Cardiac magnetic resonance (CMR) allows for analysis of cardiac function and myocardial tissue characterization. Increased left ventricular mass (LVM) is an independent predictor of cardiovascular events; however, the diagnosis of left ventricular hypertrophy and its prognostic value strongly depend on the LVM indexation method. Evaluation of the quantity and distribution of late gadolinium enhancement assists in clinical decisions on diagnosis, cardiovascular assessment, and interventions, including the placement of cardiac implantable electronic devices and the choice of an optimal procedural approach. Novel CMR techniques, such as T1 and T2 mapping, may be used for the longitudinal follow-up of myocardial fibrosis and myocardial edema or inflammation in different groups of patients, including patients with systemic sclerosis, myocarditis, cardiac sarcoidosis, amyloidosis, and both ischemic and non-ischemic cardiomyopathy, among others. Moreover, CMR tagging and feature tracking techniques might improve cardiovascular risk stratification in patients with different etiologies of left ventricular dysfunction. This review summarizes the knowledge about the current role of CMR in diagnostics and cardiovascular risk assessment to enable more personalized approach in clinical decision making.

Comment on “Prognostic value of myocardial tissue characterization by cardiac magnetic resonance imaging using T1 mapping in nonischemic dilated cardiomyopathy: a systematic review and meta-analysis”

Comment on “Prognostic value of myocardial tissue characterization by cardiac magnetic resonance imaging using T1 mapping in nonischemic dilated cardiomyopathy: a systematic review and meta-analysis”

The Role of Advanced Cardiac Imaging in Monitoring Cardiovascular Complications in Patients with Extracardiac Tumors: A Descriptive Review.

Cardiac involvement in cancer is increasingly important in the diagnosis and follow-up of patients. A thorough cardiovascular evaluation using multimodal imaging is crucial to assess any direct cardiac involvement from oncological disease progression and to determine the cardiovascular risk of patients undergoing oncological therapies. Early detection of cardiac dysfunction, particularly due to cardiotoxicity from chemotherapy or radiotherapy, is essential to establish the disease's overall prognostic impact. Comprehensive cardiovascular imaging should be integral to the clinical management of cancer patients. Echocardiography remains highly effective for assessing cardiac function, including systolic performance and ventricular filling pressures, with speckle-tracking echocardiography offering early insights into chemotoxicity-related myocardial damage. Cardiac computed tomography (CT) provides precise anatomical detail, especially for cardiac involvement due to metastasis or adjacent mediastinal or lung tumors. Coronary assessment is also important for initial risk stratification and monitoring potential coronary artery disease progression after radiotherapy or chemotherapeutic treatment. Finally, cardiac magnetic resonance (CMR) is the gold standard for myocardial tissue characterization, aiding in the differential diagnosis of cardiac masses. CMR's mapping techniques allow for early detection of myocardial inflammation caused by cardiotoxicity. This review explores the applicability of echocardiography, cardiac CT, and CMR in cancer patients with extracardiac tumors.

Diagnostic accuracy of late iodine enhancement on cardiac CT for myocardial tissue characterization: a systematic review and meta-analysis.

to evaluate the diagnostic accuracy of late iodine enhancement (LIE) in cardiac computed tomography (CCT) compared to late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR) for myocardial tissue characterization. EMBASE, PubMed/MEDLINE, and CENTRAL were searched for studies reporting the accuracy of LIE with LGE as the gold standard of reference. QUADAS-2 tool was used to assess the risk of bias. A bivariate random-effects model was used to analyze, pool, and plot the diagnostic performance measurements across studies. Pooled sensitivity, specificity, positive (+LR) and negative (-LR) likelihood ratio, diagnostic odds ratio (DOR), and hierarchical summary ROC curve (HSROC) were computed. Prospero registration number: CRD42023484045. Fourteen studies involving 526 patients and 5758 myocardial segments were included. At the patient level, LIE in CCT showed a pooled sensitivity of 0.96 (95% CI: 0.88-0.99), specificity of 0.95 (95% CI: 0.88-0.98) and the HSROC AUC of 0.98 (95% CI: 0.97-0.99). The +LR was 20.97 (95% CI: 7.54-58.38) and the -LR was 0.04 (95% CI: 0.01-0.13), resulting in a DOR of 535 (95% CI: 94-3024). At the segment level, sensitivity was 0.86 (95% CI: 0.79-0.91), specificity was 0.98 (95% CI: 0.96-0.99), and the HSROC AUC was 0.97 (95% CI:0.95-0.98). The +LR was 55.08 (95% CI: 19.94-152.16) and the -LR was 0.14 (95% CI: 0.09-0.22) with a DOR of 388 (95% CI: 113-1333). Dual-energy CCT improved segment-level sensitivity to 0.93 (95% CI: 0.88-0.96). LIE in CCT shows excellent diagnostic accuracy when compared to LGE in CMR for myocardial tissue characterization, suggesting its potential as a promising alternative to CMR. Question How does myocardial tissue characterization by late iodine enhancement (LIE) on cardiac CT (CCT) compare to late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR)? Findings LIE in CCT demonstrates excellent diagnostic accuracy, with high sensitivity and specificity at both patient and segment levels, using LGE in CMR as the reference. Clinical relevance LIE in CCT provides a reliable alternative to LGE in CMR, especially for patients for whom CMR is not available or feasible or is contraindicated, thus improving access to myocardial tissue characterization.

Diagnostic and prognostic value of quantitative cardiac magnetic resonance imaging biomarkers in systemic lupus erythematosus: a systematic review and meta-analysis.

The aim of this study was to compare CMR imaging biomarkers between SLE patients and matched controls. Electronic databases were systematically searched from inception until November 2023. All studies reporting CMR imaging data in SLE patients were included. PRISMA guidelines were followed, and risk of bias was assessed using the Newcastle-Ottawa Quality Assessment Scale. CMR findings of SLE patients were compared to that of matched controls. Clinical features associated with CMR biomarkers were collected in a qualitative analysis. A total of 64 studies were included in the systematic review pooling 3304 individuals including 1870 SLE patients. Of these, 19 case-control studies were included in the comparative meta-analysis (1576 individuals, including 884 SLE patients). Compared to controls, left ventricular (LV) ejection fraction (62% vs. 64%, p = 0.001) and indexed end-diastolic volume (77 vs. 72 mL/m2, p = 0.006) were significantly altered in SLE patients. Late gadolinium enhancement (LGE) extent was higher in SLE patients (LGE mass/total LV mass: 3.5% vs. 1.1%, p = 0.009). Native T1 and T2 relaxation times were significantly higher in SLE patients (native T1 [1.5 T]: 1005 vs. 982 ms, p = 0.02; native T1 [3 T]: 1267 vs. 1140 ms, p < 0.001; T2 [all fields]: 58 vs. 51 ms, p < 0.001). Three studies found an association between disease activity and increased T2 relaxation times. Two studies identified an association between clinical outcomes and CMR parameters. While CMR-assessed ventricular function and volumes only slightly differed in SLE patients when compared to controls, myocardial tissue characterization parameters were significantly modified and associated with disease activity. Question What are the diagnostic and prognostic values of cardiac magnetic resonance (CMR) quantitative parameters in systemic lupus erythematosus (SLE) patients? Findings Myocardial tissue characterization parameters are significantly altered in SLE patients and associated with disease activity. Clinical relevance CMR imaging demonstrates subclinical cardiac alterations in systemic lupus erythematosus patients. Additional studies are required to further demonstrate the prognostic value of CMR in SLE.

Abstract 4137854: Effect of Sacubitril/valsartan on Left Ventricular Tissue Characterization in Heart Failure with Left Ventricular Ejection Fraction Below 50%

Background: The effects of sacubitril/valsartan (ARNI) on myocardial tissue characterization in heart failure (HF) with left ventricular ejection fraction (LVEF) &lt;50% are still unclear. Objective: The present study investigated the effects of 9 months of ARNI treatment on LV structure and myocardial tissue characteristics in HF with LVEF &lt;50% using cardiac magnetic resonance (CMR). Methods: This study was a prospective, 2-arm, randomized, open-label clinical trial (SAVE-HF). Sixty-four HF outpatients with LVEF&lt;50% were randomized 1:1 from ACE inhibitor/ARB to ARNI (ARNI group) or control group (continued ACE inhibitor/ARB). CMR was performed to evaluate LV structure and tissue characteristics, including changes in LV extracellular volume fraction (delta ECV) before and after the 9-month period. The primary endpoint was difference in ECV between the two groups. Secondary endpoints included changes in LV volumes and mass, LVEF, extracellular mass (ECM) calculated as LV mass times ECV/100, and intracellular mass (ICM) calculated as LV mass minus ECM. Results: A total of 59 of 64 stable patients (68±12 years; 52 men) completed the 9-month intervention followed by repeated CMR. ARNI decreased systolic BP levels from the first month by approximately 10 mmHg. ARNI group exhibited significant reductions in LV end-diastolic and end-systolic volumes and LV mass. While LVEF and ECV remained unchanged (31.6±5.0 vs. 31.9±5.0%, p=0.26), both ECM and ICM significantly decreased after ARNI. In the control group, systolic BP, LV volumes and LV mass, ECV, ECM and ICM were unchanged. Comparing the two groups, while delta ECV was not significantly different, delta ECM was greater in ARNI group than control group (-3.6±7.3 vs. 0.2±5.3 g, p=0.025), indicating improved LV tissue characteristics. Conclusions: ARNI reduced LV volume and LV mass, accompanied with reduction of both ECM and ICM, and consequently unchanged ECV. These findings may suggest that ARNI may improve LV tissue characteristics and protect from LV remodeling in HF patients with their LVEF&lt;50%.

Assessing myocardial tissue in the acute setting with Photon-Counting CT (PCCT) in comparison with Cardiac Magnetic Resonance (CMR)

Abstract Background Cardiac magnetic resonance (CMR) characterization of myocardial tissue is routinely used in clinical practice. Compared to traditional CT, Photon counting CT (PCCT) uses photon-counting detectors offering higher spatial resolution, elimination of electronic noise and improved contrast-to-noise ratio. A comparison between CMR and PCCT for myocardial characterizazion in an urgent setting, however, has not yet been explored. Purpose The aim of this study was to compare the ability to characterize myocardial tissue between PCCT and CMR in patients presenting with acute chest pain in the emergency department (ED). Methods This single-center prospective study enrolled all consecutive patients presenting to the ED of our hospital from November 2023 to January 2024 with chest pain, ECG alterations and troponin rise consistent with myocardial injury. Patients needing urgent coronary angiography according to guidelines were excluded. PCCT was performed urgently for triple rule-out, but also for tissue characterization through post-iodine-contrast administration images. Within 24 hours, all patients underwent a CMR protocol including T2-weighted and late gadolinium enhancement (LGE) images for tissue characterization. Results Six male patients with a mean age of 20 ± 10 years were enrolled. All clinical, PCCT, and CMR parameters are presented in Table 1. All patients presented with diffuse ST-segment elevation and exhibited T2-weighted images (for edema detection) and LGE distribution (subepicardial and intramyocardial) consistent with acute myocarditis. Mean radiation exposure for PCCT was 0.8±0.1 mSv. A strong linear correlation emerged between PCCT-derived delayed enhancement (DE) volume and CMR-derived late gadolinium enhancement (LGE) volume (r = 0.970; p value 0.001) (Table 1). Similar results were achieved when comparing the number of DE and LGE myocardial segments (r = 0.871; p value 0.026). Significant correlations also emerged between DE, LGE, and high-sensitive troponin (hsTN) at presentation (respectively: PCCT-DE vs hsTN r = 0.951, p value 0.004; CMR-LGE vs hsTN r = 0.918, p value 0.010). CMR showed a much higher signal-to-noise ratio (SNR) for the delayed enhanced myocardium and contrast-to-noise (CNR) ratio between the delayed enhanced and normal myocardium with respect to PCCT in post-contrast images (respectively 7.4 ± 3.9 vs 27.2 ± 17.7, p value 0.024 and 5.5 ± 3.7 vs 38.8 ± 30.2, p value 0.023). In T2-weighted images both SNR for the hyperintense myocardium (30.3 [20.4-122.4]) and CNR between the hyperintense and normal myocardium (26.7 [13.3-60.2]) resulted to be higher compared to PCCT (p value 0.027 and 0.045, respectively) (Table 1). Conclusions PCCT appears to be reliable when compared to CMR for detecting myocardial edema through the acquisition of post-contrast images in the acute setting with an acceptable CNR.

CMR characterisation of patients with heart failure and left bundle branch block

Abstract Introduction Cardiac magnetic resonance (CMR) is recommended internationally for tissue characterisation, volumetric assessment and assessment of prior myocardial infarction (1). Patients with left bundle branch block (LBBB) form a significant sub-group of individuals, however, there is limited data available to accurate determine whether LBBB is associated with any CMR-definable phenotypes. Aim We aimed to identify the distinctive cardiac magnetic resonance (CMR) features of patients with left bundle branch block (LBBB) and heart failure with reduced ejection fraction (HFrEF) of presumed non-ischaemic aetiology. Methods Participants from the MATCH (MyocArdial Tissue CHaracteristics in patients with heart failure according to glycaemic status) registry were prospectively enrolled. Exclusion criteria included: LVEF &amp;gt;40% at initial evaluation, established diagnosis of coronary artery disease, known presence of structural heart disease, suspected myocarditis, congenital heart disease and significantly impaired renal function. Following identification of HF, guideline-directed medical therapy was initiated based on the decision of the treating physician. LV recovery was defined as achieving ≥10% absolute improvement to a level of 40% or greater of LVEF from baseline evaluation upon the date of CMR quantification. Electrocardiograms were analysed to establish the presence or absence of LBBB. Results A total of 391 patients were recruited including 115 (29.4%) presenting with LBBB. Compared to controls, LBBB patients exhibited larger left ventricles and smaller right ventricles, but no differences were observed with respect to LVEF (35.8±12 vs. 38± 12 %, p=0.105) or right ventricular ejection fraction (RVEF). The prevalence of ischaemic scar (18.3% vs 21%, p=0.54), non-ischaemic fibrosis (25.2% vs 32.6%, p=0.15) and inducible ischaemia (6.1% vs. 7.6%, p=0.6) was comparable in patients with LBBB and those without. The overall rate of LV recovery was not significantly different between LBBB and non-LBBB patients (27.8% vs. 33%, p=0.32) from their baseline evaluation to the time of CMR assessment (70 [42 - 128] days). In the multivariate logistic regression, reduced LVEF remained an independent predictor of LV non-recovery in patients with LBBB, even after adjusting for gender and QRS duration (OR 0.93, 95%CI 0.87 – 0.99, p=0.03). In contrast, this association was not observed among patients without LBBB, whereas ischaemic scar was the primary predictor of LV non-recovery (OR 4.31, 95%CI 1.85 – 10.04, p=0.0007). Conclusion In this study patients presenting with a combination of HFrEF and LBBB had a larger LV cavity and smaller RV cavity than those without LBBB. However, there were no differences in the prevalence of ischaemic scar, non-ischaemic scar of inducible ischaemia according to the presence of absence of LBBB. Rates of LV recovery were similar between LBBB and non-LBBB patients.Clinical CMR ParametersSegmental Distributions

Mechanical wave velocities in acute myocardial infarction: an exploratory study using three-dimensional high frame rate echocardiography

Abstract Background Evaluation of cardiac function is crucial for management of patients with acute myocardial infarction (AMI). Recently, high frame rate (HFR) echocardiography has enabled identification of fast-propagating mechanical waves (MW) within the myocardium. These waves have the potential to offer unique insights into myocardial tissue properties, including edema and fibrosis. However, the potential of 3D HFR echocardiography to accurately quantify MW velocities and thereby assess myocardial stiffness in AMI patients remains unexplored. Purpose To assess the feasibility of a novel method for estimating MW velocities using 3D HFR echocardiography in patients with AMI compared to healthy controls. Methods Twenty patients with first time ST-elevation myocardial infarction were included within 48 hours after reperfusion therapy. We used a commercially available ultrasound scanner to acquire conventional 3D high-quality (~20 frames per second) acquisitions and subsequent 3D HFR recordings (~820 frames per second). The high-quality recording was used to extract a myocardial mask to define the region of interest in the HFR acquisition to detect the atrial kick wave and generate a comprehensive 3D map of MW propagation and velocities. We compared MW velocities between these patients and twenty age- and sex-matched healthy controls. Results MW velocities were successfully measured in 93% of participants (17 patients and 20 controls). Global MW velocities were significantly higher in AMI patients compared to healthy controls (2.1±0.6m/s vs. 1.5±0.2m/s, p&amp;lt;0.001). Territorial values, corresponding to the theoretical perfusion area of the three main coronary arteries, were significantly higher in infarct-related territories in patients when compared to same territories in controls for all coronary territories: Right coronary artery: 1.9±0.7 m/s vs. 1.4±0.3m/s, p&amp;lt;0.05; Circumflex artery: 3.1±1.5m/s vs. 1.7±0.4m/s, p&amp;lt;0.01; and Left anterior descending artery: 1.8±0.5m/s vs. 1.4±0.2m/s, p&amp;lt;0.01. Conclusions Estimation of MW velocities using a novel 3D HFR echocardiography method was feasible in most patients with AMI and all healthy controls. MW velocities were higher in patients compared to healthy controls and infarcted compared to non-infarcted coronary territories. These findings confirm the potential of non-invasive myocardial tissue characterization by MW imaging.Boxplot of MW velocities3D HFR MW visualisation

Diabetes worsens the adverse association between myocardial diffuse fibrosis and left ventricular strain

Abstract Background Heart failure is a common cardiovascular complication to diabetes. Increased fibrosis of the myocardium has been suggested to be a mechanism, however, no convincing clinical evidence has so far been presented. A better understanding of how myocardial tissue characteristics influence functional aberration in diabetes could aid diagnosis, risk assessment and guide treatment. Native T1 is a CMR marker of diffuse fibrosis with diagnostic and prognostic value (1,2), and feature tracking (CMR-FT) strain is a sensitive measure of myocardial systolic function. In this study, we evaluated the association of CMR markers of fibrosis with markers of systolic function in individuals with and without diabetes. Purpose To understand the relationship between native T1 and myocardial strain and how diabetes may affect this. Methods Participants from the UK Biobank population imaging study were included. Left ventricular global longitudinal strain (GLS) was derived using a semi-automated batch processing software tool. Native T1 was derived from segmentation of the entire short axis slice using an automated quality control tool, excluding scans with predicted dice score of &amp;lt;0.7. Multivariable linear models were used with the strain metrics as the outcome variable and native T1 and diabetes as the exposure variables. These models were adjusted for age, sex, BMI, ethnicity, smoking and alcohol status, prevalent hypertension hypercholesterolaemia and coronary artery disease. The effect of interaction between diabetes and native T1 on GLS was examined by introducing an interaction term. Results In total 41,533 participants were included, of which 1957 had diabetes – see Table 1 for baseline characteristics. The average GLS measured for those with diabetes was -17% and was -18% for those without. The average native T1 in those with diabetes was 935ms and 933ms for those without on the background of greater prevalence of cardiovascular risk factors in those with diabetes. In model adjusted for all relevant co-variates, individuals with diabetes had worse GLS measured compared to those without diabetes (β-coefficient: 0.51, p value &amp;lt;0.001). Increasing fibrosis (native T1) was associated with worsening GLS (β-coefficient: 0.005, p value &amp;lt;0.001) in all participants. However, in those with diabetes, increasing native T1 was associated with a greater decline in GLS compared to those without diabetes (interaction term β-coefficient: 0.005, p value &amp;lt;0.001), with a relative impairment seen within normal ranges for native T1 - see Figure 1. Conclusion(s) This is the largest study of its kind to demonstrate a dose dependent relationship between increasing native T1, representing potential myocardial fibrosis, and myocardial strain, representing cardiac dysfunction. Our findings indicate that increased fibrosis alone does not explain the higher risk of HF in diabetes, other mechanisms, perhaps intracellular, might be at play.

Prognostic value of myocardial tissue characterization by cardiac magnetic resonance imaging using T1 mapping in nonischemic dilated cardiomyopathy: a systematic review and meta-analysis

This study aimed to evaluate the prognostic value of T1 mapping techniques via cardiac magnetic resonance (CMR) in nonischemic dilated cardiomyopathy (NICM) patients. PubMed and Google Scholar were searched for studies examining the prognostic value of myocardial tissue characterization via CMR imaging with T1 mapping in NICM. Major adverse cardiac events (MACE) included cardiac death, ventricular arrhythmia/sudden cardiac death (SCD) events, and heart failure events. Ten studies with a total of 3,384 patients (mean age 50.4 years; mean follow-up 28.0 months) were analyzed. The meta-analysis demonstrated that in patients with MACE, the mean extracellular volume (ECV) was greater than in those without MACE (MD: -5.40%; 95% CI: -7.91 to -2.90%; p < 0.0001). Furthermore, in patients with MACE, the native T1 value was alsogreater than in those without MACE (MD: - 38.87 ms; 95% CI: -59.01 to -18.74 ms; p = 0.0002). A meta-analysis showed a significant relationship between ECV and the risk of MACE (HRunadjusted: 1.19 per 1% ECV; 95% CI: 1.10-1.28; p < 0.001). After adjusting for baseline characteristics, higher ECV remained strongly associated with MACE risk (HRadjusted: 1.21 per 1% ECV; 95% CI: 1.11-1.31; p < 0.001). Higher native T1 time was also significantly associated with MACE development (HRunadjusted: 1.09 per 10 ms T1 time; 95% CI:1.02-1.15; p = 0.007). After adjustments, the association remained significant (HR adjusted: 1.01 per 10 ms T1 time; 95% CI: 1.00-1.03; p = 0.02). Meta-analysis demonstrates the risk of MACEbeing significantly associated with a higher mean ECV fraction and native T1 time, suggesting these indices as novel risk markers to identify high-risk NICM patients.

Characterizing myocardial edema and fibrosis in hypertensive crisis with cardiovascular magnetic resonance imaging.

A hypertensive crisis is associated with an increased risk of cardiovascular events. Although altered cardiac structure, function, and myocardial architecture on cardiovascular magnetic resonance (CMR) have been associated with increased adverse events in hypertensive patients, the studies did not include patients with hypertensive crisis. Our study aimed to determine myocardial tissue characteristics in patients with hypertensive crisis using CMR imaging. Participants underwent comprehensive CMR imaging at 1.5T. The imaging protocol included cine-, T2-weighted-, contrasted- and multi-parametric mapping images. Blood and imaging biomarkers were compared in hypertensive emergency and hypertensive urgency. Predictors of myocardial edema was assessed using linear regression. The predictive value of T1- and T2 mapping for identifying hypertensive emergency (from urgency) was assessed with receiver operator characteristics curves. Eighty-two patients (48.5 ± 13.4 years, 57% men) were included. Hypertensive emergency constituted 78%. Native T1 was higher in patients with LVH compared to those without (1056 ± 33 vs. 1013 ± 40, P < 0.001), and tended to be higher in hypertensive emergency than urgency (1051 ± 37 vs. 1033 ± 40, P = 0.077). T2-w signal intensity (SI) ratio and T2 mapping values were higher in hypertensive emergency (1.5 ± 0.2 vs. 1.4 ± 0.1, P = 0.044 and 48 ± 2 vs. 47 ± 2, P = 0.004), and in patients with than without LVH (1.5 ± 0.2 vs. 1.4 ± 0.1, P = 0.045 and P = 0.030). A trend for higher extracellular volume was noted in hypertensive emergency compared to urgency (25 ± 4 vs. 22 ± 3, P = 0.050). Native T1 correlated with T2 mapping (rs = 0.429, P < 0.001), indexed LV mass (rs = 0.493, P < 0.001), cardiac troponin (rs = 0.316, P < 0.001) and NT-proBNP (rs = 0.537, P < 0.001), while T2 correlated with cardiac troponin (rs = 0.390, P < 0.001), and NT-proBNP (rs = 0.348, P < 0.001). Non-ischemic LGE pattern occurred in 59% and was 21% more prevalent in the hypertensive emergency group (P = 0.005). Our findings demonstrate that hypertensive crisis is associated with distinct myocardial tissue alterations, including increased myocardial edema and fibrosis, as detected on CMR. Patients with hypertensive emergency had a higher degree of myocardial oedema than hypertensive urgency. Further research is necessary to explore the prognostic value of these findings.

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.

414 - Myocardial tissue characterization of cardiac fibrosis as an early marker of heart failure in diabetic patients

414 - Myocardial tissue characterization of cardiac fibrosis as an early marker of heart failure in diabetic patients

Cardiovascular Magnetic Resonance Imaging of Takotsubo Syndrome: Evolving Diagnostic and Prognostic Perspectives.

Takotsubo syndrome (TS) is a temporary form of left ventricular (LV) dysfunction characterized by a distinct pattern of LV impairment, often triggered by a physical or emotional stressful event. Historically, TS was considered a benign condition due to its prompt restoration of myocardial function and generally excellent outcomes. However, recent studies have shown that complications similar to those seen after myocardial infarction can occur, necessitating careful monitoring of these patients. Among noninvasive imaging techniques, cardiovascular magnetic resonance (CMR) is becoming increasingly important in evaluating patients with TS. CMR offers a unique ability to noninvasively assess myocardial tissue characteristics, allowing for detecting the typical features of TS, such as specific wall motion abnormalities and myocardial edema. Beyond its well-established diagnostic utility in the clinical management of TS, CMR has also proven valuable in prognosis and risk stratification for these patients. Advances in CMR, including myocardial strain and parametric mapping have expanded its role in the diagnosis, prognosis, and follow-up of these patients. This review aims to provide a comprehensive overview of the potential applications of CMR in the diagnostic and prognostic evaluation of TS patients. It explores the emerging use of novel CMR imaging biomarkers that may enhance diagnosis, improve prognostic accuracy, and contribute to the overall management of these patients.

The “Padua classification” of cardiomyopathies: Combining pathobiological basis and morpho-functional remodeling

Over the last 20 years, the scientific progresses in molecular biology and genetics in combination with the increasing use in the clinical setting of contrast-enhanced cardiac magnetic resonance (CMR) for morpho-functional imaging and structural myocardial tissue characterization have provided important new insights into our understanding of the distinctive aspects of cardiomyopathy, regarding both the genetic and biologic background and the clinical phenotypic features. This has led to the need of an appropriate revision and upgrading of current nosographic framework and pathobiological categorization of heart muscle disorders.This article proposes a new definition and classification of cardiomyopathies that rely on the combination of the distinctive pathobiological basis (genetics, molecular biology and pathology) and the clinical phenotypic pattern (morpho-functional and structural features), leading to the proposal of three different disease categories, each of either genetic or non-genetic etiology and characterized by a combined designation based on both “anatomic” and “functional” features, i.e., hypertrophic/restrictive (H/RC), dilated/hypokinetic (D/HC) and scarring/arrhythmogenic cardiomyopathy (S/AC).The clinical application of the newly proposed classification approach in the real-world practice appears crucial to design a targeted clinical management and evaluation of outcomes of affected patients. Although current treatment of cardiomyopathies is largely palliative and based on drugs, catheter ablation, device or surgical interventions aimed to prevent and manage heart failure and malignant arrhythmias, better knowledge of basic mechanisms involved in the onset and progression of pathobiologically different heart muscle diseases may allow to the development of disease-specific curative therapy.

T2 mapping post acute myocardial infarction: a novel technique in assessing myocardial edema

ObjectiveCardiovascular magnetic resonance (CMR) is considered the gold standard imaging modality for assessing myocardial infarction lesions, offering precise myocardial tissue characterization. Elevated transverse relaxation time (T2) serves as a specific indicator of increased myocardial water content, thus becoming a valuable index for myocardial edema. However, conventional T2-weighted CMR sequence exhibits several limitations, primarily providing qualitative information. In contrast, recently developed quantitative T2 mapping techniques overcome these limitations, enabling a more reliable assessment of myocardial edema. These techniques offer the advantage of diagnosing and monitoring myocardial injury without the necessity of contrast agents. Our study aims to add to a growing literature demonstrating the efficacy of quantitative T2 mapping technique to detect and quantify regions of myocardial edema post-myocardial infarction.ResultNative T1 and T2 mapping accurately identified myocardial edema in all patients enrolled in the study. Notably, native T1 and T2 values exhibited a significant elevation in the infarcted myocardium compared to the remote myocardium (for T1: 1295.50 ± 87.65 vs. 1074.95 ± 92.86 ms, respectively; and for T2: 74.63 ± 6.51 vs. 52.53 ± 6.26 ms, respectively; p < 0.0001 for both). Microvascular obstruction was observed in 12 out of 20 patients, affecting one or more myocardial segments within the infarct areas. Among this subgroup, regions with a microvascular obstruction within the infarct zone displayed lower T1 and T2 values compared to areas of infarction without microvascular obstruction (for T1: 1115.05 ± 64.70 vs. 1295.50 ± 87.65 ms, respectively; and for T2: 53.65 ± 3.56 vs. 74.63 ± 6.51 ms, respectively; p < 0.0001 for both). Additionally, we provided reference values for myocardial T1 and T2 specific to our facility’s 1.5 Tesla CMR system, applicable to both infarct and remote myocardium.ConclusionParametric T1 and T2 mapping techniques can detect and quantify myocardial edema resulting from myocardial infarction. The presence of microvascular obstruction that results from revascularization injury affects both T1 and T2 values. This information can be used and has broad clinical implications for diagnosis and guiding or monitoring the treatment of myocardial infarction.

Cardiac magnetic resonance for ventricular arrhythmias: a systematic review and meta-analysis

BackgroundCardiac magnetic resonance (CMR) allows comprehensive myocardial tissue characterisation, revealing areas of myocardial inflammation or fibrosis that may predispose to ventricular arrhythmias (VAs). With this study, we aimed to estimate...

A comprehensive experimental analysis of the local passive response across the healthy porcine left ventricle

This work provides a comprehensive characterization of porcine myocardial tissue, combining true biaxial (TBx), simple triaxial shear (STS) and confined compression (CC) tests to analyze its elastic behavior under cyclic loads. We expanded this study to different zones of the ventricular free wall, providing insights into the local behavior along the longitudinal and radial coordinates. The aging impact was also assessed by comparing two age groups (4 and 8 months). Resulting data showed that the myocardium exhibits a highly nonlinear hyperelastic and incompressible behavior. We observed an anisotropy ratio of 2-2.4 between averaged peak stresses in TBx tests and 1-0.59-0.40 orthotropy ratios for normalised fiber-sheet-normal peak stresses in STS tests. We obtained a highly incompressible response, reaching volumetric pressures of 2-7 MPa for perfused tissue in CC tests, with notable differences when fluid drainage was allowed, suggesting a high permeability. Regional analysis showed reduced stiffness and anisotropy (20-25%) at the apical region compared to the medial, which we attributed to differences in the fiber field dispersion. Compressibility also increased towards the epicardium and apical regions. Regarding age-related variations, 8-month animals showed stiffer response (at least 25% increase), particularly in directions where the mechanical stress is absorbed by collagenous fibers (more than 90%), as supported by a histological analysis. Although compressibility of perfused tissue remained unchanged, permeability significantly reduced in 8-month-old animals. Our findings offer new insights into myocardial properties, emphasizing on local variations, which can help to get a more realistic understanding of cardiac mechanics in this common animal model. Statement of significanceIn this work, we conducted a comprehensive analysis of the passive mechanical behavior of porcine myocardial tissue through biaxial, triaxial shear, and confined compression tests. Unlike previous research, we investigated the variation in mechanical response across the left ventricular free wall, conventionally assumed homogeneous, revealing differences in terms of stiffness and compressibility. Additionally, we evaluated age-related effects on mechanical properties by comparing two age groups, observing significant variations in stiffness and permeability. To date, there has been no such in-depth exploration of myocardial elastic response and compressibility considering regional variations along the wall and may contribute to a better understanding of the cardiac tissue’s passive mechanical response.