Late Gadolinium Enhancement Sequences Research Articles

Prognostic value of cardiac magnetic resonance - LGE distribution in non-ischemic dilated cardiomyopathy for prophylactic implantable-cardioverter defibrillator therapy

Abstract Background/Introduction International guidelines recommend implantable cardioverter-defibrillator (ICD) implantation when patients with nonischemic dilated cardiomyopathy (NICM) have left ventricular ejection fraction (LVEF) of 35% or less. Tissue characterization obtained by cardiac magnetic resonance (CMR) has emerged as a promising tool for better identification of patients at high arrhythmic risk and thus worthy of prophylactic ICD therapy. Purpose Current analysis has the scope to assess the prognostic value of fibrosis as evaluated by late gadolinium enhancement sequences (LGE) specifically regarding its LV wall distribution. The primary endpoint was all-cause mortality. The secondary end-point consisted of major adverse arrhythmic cardiac events (MAACE), defined as combination of SCD, aborted SCD, and sustained ventricular tachycardia. Methods Study population is part of DERIVATE Study, an international, multicenter, prospective, observational registry including consecutive patients from 21 sites across Europe and US referred for heart failure (HF) work-up including transthoracic echocardiography (TTE) and CMR without a history of previous major ventricular arrhythmias. Inclusion criteria were: (i) aged 18 or older, (ii) chronic HF according to the ESC Task force definition, and (iii) LV-EF<50% at initial TTE. All patients underwent TTE and CMR within 3 months. Patients with (i) decompensated within 3 months of enrollment, (ii) recent myocardial infarction (<40 days), (iii) unstable angina, (iv) severe valvular disease, (v) primary or secondary cardiomyopathies other than NICM, (vi) cardiac amyloidosis, and (vii) congenital heart disease were excluded. Results The entire cohort consisted of 1384 subjects [mean age: 56±14 years, male: 948 (68.4%)]. The median follow-up time was 959 days. Mortality and MAACE occurred in 92 (6.6%) and 125 (9%) patients, respectively. SCD, aborted SCD, and sustained VT occurred in 15 (1.1%), 80 (5.8%), and 104 (7.5%), respectively. In the multivariate analyses for all-cause mortality, only the number of segments with LGE at the level of the septum was an independent predictor (p=0.002), while in the analyses for MAACE the only independent predictors were male gender, LVEDVi by CMR, and the number of segments with LGE at the level of septum inferior. Based on the multivariate analysis, the DERIVATE score (including all 1384 patients) ranging from 0 to 8 (Cox regression analysis HR=1.35, 95%CI 1.24-1.46, p< 0.001) was built up. The redistribution of patients according to the CMR composite DERIVATE risk/year MAACE was of 44%, 37% and 32% for the low, intermediate and high risk groups, respectively. Conclusions The arrhythmic risk of patients with NICM is also dependent on the different distribution of fibrosis in the LV. The redistribution of the event rate according to the CMR composite risk score indicates the potential to alter the decision on ICD implantation in a relevant portion of NICM patients.

Left Ventricular Global Longitudinal Strain (LV GLS) assessed by Echocardiography predicts myocardial fibrosis and iron overload in transfusion dependent beta-thalassemia patients

Abstract Background Cardiac involvement represents the leading cause of death in transfusion dependent beta-thalassemia (TDT) patients. It is mainly related to cardiac iron overload and myocardial fibrosis, causing progressive damage and a deterioration of systolic and diastolic function. Moreover, myocardial fibrosis may not be directly related with the degree of cardiac iron deposition and it is associated with a higher risk of cardiovascular complications. To date, Cardiac Magnetic Resonance (CMR) is the gold standard for the evaluation of iron overload with T2* sequences and for the detection of myocardial fibrosis with late gadolinium enhancement (LGE). However, CMR is not always feasible. Left Ventricular Global Longitudinal Strain (LV GLS) with Speckle Tracking Echocardiography (STE) is a non-invasive imaging tool, which may play a key role in the early recognition of subclinical myocardial damage and dysfunction (figure 1). Purpose The aim of this study was the evaluation of the role of LV GLS with STE in the characterization of myocardial involvement in a population of TDT patients. Methods An observational, cross-sectional, monocentric study was conducted enrolling 44 patients with TDT from the outpatient clinic of hematology located in our teritary hospital from January 2022 to December 2022. Each patient underwent a thorough clinical evaluation, laboratory testing, transthoracic echocardiogram (TTE) with LV GLS-STE by a trained cardiologist and contrast enhanced CMR with T2* technique and LGE sequences. A T2* value < 20 msec was set to define the presence of iron overload. Results The mean age of patients was 39± 9 years with a slight prevalence of female sex (53% vs 47% respectively). Atherosclerotic cardiovascular risk factors were rarely present, the most common was arterial hypertension in about 12% of patients. The TTE pointed out a left ventricular ejection fraction within the normal range (mean value of 59 ± 5%). As regards LV GLS, the mean value was -21.1 ± 3.0%. Cardiac iron overload was observed in 18% of patients, while about 15% of patients had cardiac fibrosis. A clinical and statistically significant difference was observed between LV GLS values in patients with cardiac iron overload as compared to patients without (-18.2 ± 2.1% vs -20.6 ± 3.1%; p value=0.043). A clinical and statistically significant difference was documented, also, between LV GLS values in patient with cardiac fibrosis as compared to patient without LGE (-16.4 ± 1.7% vs -20.6 ± 2.8%; p value=0.002). As regards cardiac fibrosis, a LV GLS cut-off value of -18,3% was found by the analysis of ROC curve with an AUC of 0.931 (95% CI: 0.846-1.000) (figure 2). Conclusions In a small population of TDT patients we observed that LV GLS with STE may be a promising tool able to help clinicians in the early identification of cardiac iron overload and fibrosis, providing useful information for diagnostic workup and therapeutic approach.

Cardiac troponin T and I are differentially associated with myocardial fibrosis assessed by cardiac magnetic resonance imaging

Abstract Background Cardiac troponin T (cTnT) is more potently associated with non-cardiovascular (CV) mortality and cardiac troponin I (cTnI) is more specific for CV risk in the general population. Cardiovascular magnetic resonance imaging (CMR) measurement of extracellular volume (ECV) allows for assessment of diffuse myocardial fibrosis and is associated with adverse CV events. Focal myocardial scars are assessed by late gadolinium enhancement (LGE) and LGE scar presence is associated with unfavorable CV outcomes. The distinct clinical outcomes associated with cTnT and cTnI may be due to different subtypes and burden of myocardial fibrosis. Elevation of cTnT associates with increased ECV in a CMR referral base and with nonischemic myocardial scars in the general population. There is limited data comparing the associations of cTnT and cTnI with CMR indices of fibrosis in the general population. Purpose Perform head-to-head comparison of the associations of cTnT (Roche Elecsys) and cTnI (Abbott Alinity) with diffuse and focal myocardial fibrosis assessed by CMR. Methods Two hundred community-dwellers born in 1950 with approximately similar sex distribution were recruited. All participants were without contraindications to contrast-enhanced CMR, had normal kidney function and no known coronary artery disease. For the study a 1.5-T Philips MRI clinical scanner was used. Diffuse fibrosis was estimated by septal ECV and focal scars were quantified by LGE and classified as either ischemic or nonischemic. Complete MOLLI-sequence for assessment of ECV was present in 192 participants and 198 participants had complete LGE sequence. Logistic regression analysis was used to examine relationships between log transformed cardiac troponins and CMR indices of myocardial fibrosis, adjusting for a priori selected established cardiovascular risk factors. We analyzed ECV according to cut-off values based on the upper sex-specific quartile. Results The median age was 69 (68.6-69.3) and 52% were male (Table 1). The upper sex-specific quartile of ECV was 27% for men and 28% for women. cTnT was associated with ECV in the fully adjusted model (odds ratio [OR] 1.98, 95% CI 1.08-3.64), in contrast to cTnI which was not associated with ECV in any of the models (Table 2). cTnT (OR 3.71 95% CI 1.83-7.50) and cTnI (OR 1.69 95% CI 1.24-2.30) were associated with the presence of any LGE scar in the fully adjusted model, but the association was stronger for cTnT (p for comparison = 0.024). cTnT and cTnI were significantly associated with nonischemic scars in all models (Table 2), but stronger for cTnT (p for comparison = 0.018). In the fully adjusted model only cTnI was associated with the presence of ischemic scars (OR 1.66 95% CI 1.05-2.61). Conclusion(s) In our cohort of community-dwellers, cTnT is the stronger marker of diffuse and nonischemic myocardial fibrosis, while cTnI seems to more strongly reflect the presence of ischemic scar as assessed by CMR.Participant characteristicsAssociations of cTnT and cTnI

Abstract 18920: Left Atrial Function is Associated With Left Ventricular Mass in Women With Preserved Left Ventricular Ejection Fraction and Late Gadolinium Enhancement on Cardiac MRI

Introduction: Myocardial fibrosis detected by late gadolinium enhancement (LGE) on cardiac MRI may be related to conditions with increased left ventricular (LV) mass and diastolic dysfunction. Women have an increased incidence of LV diastolic dysfunction and poorer clinical outcomes compared to men. Aim: To examine gender-based associations between LV mass and left atrial total emptying fraction (LATEF), a surrogate for diastolic function, in patients with LGE on cardiac MRI. Methods: We analyzed 134 consecutive patients undergoing cardiac MRI and LGE sequences on a 1.5T GE scanner. LV mass and LV/LA volumes (indexed by BSA) were measured offline from cine SSFP images using Precession software. Presence of LGE was reported. Nonparametric analyses were performed. Results: 40 patients with more than mild mitral regurgitation, pericardial disease, or LVEF <50% were excluded. 94 patients studied (49% women) had a median age of 51 years [IQR 38-67] with no gender-based difference. Median LV mass index (LVMi) for all patients was 69.5 g/m2 [IQR 57-82] and was higher in LGE vs no-LGE patients (p<0.001) and higher in men vs women (p<0.05). Median LATEF for all patients was 0.50 [IQR 0.41-0.54] and was lower in LGE vs no-LGE patients (p<0.001) with no gender-based difference. LVMi had a strong inverse correlation with LATEF for all patients and for the LGE group (r=-0.58, p<0.001 and r=-0.51, p<0.001 respectively). LVMi had a very strong inverse correlation with LATEF (r=-0.74, p<<0.001) in women with LGE and moderate inverse correlation in women with no-LGE (r=-0.45, p=0.02). LVMi had a moderate inverse correlation with LATEF in men with LGE (r=-0.48, p. <0.01) and no correlation in men with no-LGE (Figure). Conclusions: LA function inversely correlates with indexed LV mass, most strongly in women with LV LGE. Further exploration of these parameters may allow earlier detection of LV diastolic dysfunction and improved risk stratification.

Prevalence of Pericardial Late Gadolinium Enhancement in Patients After Cardiac Surgery: Clinical and Histological Correlations.

Pericardial late gadolinium enhancement (LGE) is usually associated with active pericarditis, but it is not infrequently found in patients after cardiac surgery even a long time after the intervention. The clinical relevance of this finding and its histological correlates are unknown. We sought to determine the prevalence of chronic pericardial LGE in patients after cardiac surgery. All consecutive patients with previous cardiac surgery, who were referred to cardiovascular magnetic resonance between January 2017 and December 2021 were enrolled in the study. Cardiovascular magnetic resonance examination protocol was adapted to clinical indication but always included standard LGE acquisitions. Two independent observers blinded to clinical data assessed the presence of pericardial enhancement on LGE sequences. Fifteen patients underwent cardiac reintervention and pericardial biopsies were obtained. The primary study end point was to assess the prevalence of pericardial enhancement after cardiac surgery and identify possible determinants. The secondary end point was to correlate pericardial enhancement with clinical symptoms and histopathology. Two hundred four patients were included in the study. The median time between surgery and cardiovascular magnetic resonance was 160 months (35-226 months). Pericardial LGE was observed in 90 patients (44%). All patients were asymptomatic, and no specific treatment for pericarditis was started. All patients remained asymptomatic at a 1-year clinical follow-up. Pericardial LGE was significantly correlated with the number of previous surgeries (P=0.03). Pericardial fibrosis was detected in all 15 pericardial biopsy specimens; pericardial LGE was present in 7 patients (47%) who underwent biopsy. Histological signs of low-grade inflammation were detected in 6 patients (40%) with severe, circumferential pericardial LGE but in no patient without pericardial enhancement. Pericardial LGE is a frequent finding even several years after cardiac surgery. Its histological correlate is a chronic subclinical post-pericardiotomy inflammation.

Incorporation of view sharing and KWIC filtering into GRASP-Pro improves spatial resolution of single-shot, multi-TI, late gadolinium enhancement MRI.

While single-shot late gadolinium enhancement (LGE) is useful for imaging patients with arrhythmia and/or dyspnea, it produces low spatial resolution. One approach to improve spatial resolution is to accelerate data acquisition using compressed sensing (CS). Our previous work described a single-shot, multi-inversion time (TI) LGE pulse sequence using radial k-space sampling and CS, but over-regularization resulted in significant image blurring that muted the benefits of data acceleration. The purpose of the present study was to improve the spatial resolution of the single-shot, multi-TI LGE pulse sequence by incorporating view sharing (VS) and k-space weighted contrast (KWIC) filtering into a GRASP-Pro reconstruction. In 24 patients (mean age = 61 ± 16 years; 9/15 females/males), we compared the performance of our improved multi-TI LGE and standard multi-TI LGE, where clinical standard LGE was used as a reference. Two clinical raters independently graded multi-TI images and clinical LGE images visually on a five-point Likert scale (1, nondiagnostic; 3, clinically acceptable; 5, best) for three categories: the conspicuity of myocardium or scar, artifact, and noise. The summed visual score (SVS) was defined as the sum of the three scores. Myocardial scar volume was quantified using the full-width at half-maximum method. The SVS was not significantly different between clinical breath-holding LGE (median 13.5, IQR 1.3) and multi-TI LGE (median 12.5, IQR 1.6) (P = 0.068). The myocardial scar volumes measured from clinical standard LGE and multi-TI LGE were strongly correlated (coefficient of determination, R2 = 0.99) and in good agreement (mean difference = 0.11%, lower limit of the agreement = -2.13%, upper limit of the agreement = 2.34%). The inter-rater agreement in myocardial scar volume quantification was strong (intraclass correlation coefficient = 0.79). The incorporation of VS and KWIC into GRASP-Pro improved spatial resolution. Our improved 25-fold accelerated, single-shot LGE sequence produces clinically acceptable image quality, multi-TI reconstruction, and accurate myocardial scar volume quantification.

Feasibility of gray-blood late gadolinium enhancement evaluation in young patients with congenital and acquired heart disease.

Late gadolinium enhancement (LGE) sequences have become common in pediatric cardiovascular magnetic resonance (CMR) to assess for myocardial fibrosis. Bright-blood late gadolinium enhancement (BB-LGE) by conventional phase-sensitive inversion recovery (PSIR) is commonly utilized, but similar inversion time (TI) value of fibrosis and left ventricular (LV) blood pool can make subendocardial areas difficult to assess. A gray-blood LGE (GB-LGE) technique has been described, targeting nulling of the LV blood pool and demonstrating improvement in ischemic scar detection over BB-LGE in adult patients. We sought to evaluate the feasibility of the GB-LGE technique in a young population with congenital and acquired heart disease and compare its ability to detect subendocardial scar to conventional BB-LGE. Seventy-six consecutive patients referred for clinical CMR underwent both BB-LGE and GB-LGE on 1.5 T and 3 T scanners. Conventional PSIR sequences were obtained with TI to null the myocardium (BB-LGE) in short-axis and horizontal long-axis stacks. Same PSIR stacks were immediately repeated with TI to null the blood pool (GB-LGE). Both sequences were reviewed separately a week apart by two readers, blinded to the initial clinical interpretation. Studies were analyzed for overall image quality, confidence in scar detection, confidence in detection of LGE, LGE class, inter- and intra-observer agreement for the presence of scar, and intraclass correlation coefficient (ICC) for total scar burden. Overall confidence in myocardial scar detection by BB-LGE or GB-LGE as well as grading of image quality were not statistically different [(p = 1 and p = 1) and (p = 0.53, p = 0.18), respectively]. There was very good inter-observer agreement for the presence of scar on BB-LGE (K = 0.88, 95% CI 0.77-0.99) and GB-LGE (K = 0.84, 95% CI 0.7-0.96), as well as excellent intra-observer agreement for both readers (K = 0.93, 95% CI 0.87-0.99; and K = 0.81, 95% CI 0.69-0.95). Interclass correlation coefficient for total scar burden was excellent for BB-LGE (ICC = 0.98, 95% CI 0.96-0.99) and GB-LGE (ICC = 0.94, 95% CI 0.91-0.97). The GB-LGE technique is feasible in the pediatric population with congenital and acquired heart disease. It can detect subendocardial/ischemic scar similar to conventional bright-blood PSIR sequences in the pediatric population.

Assessment of Pulmonary Arteries Hemodynamics and Its Relationship With Cardiac Remodeling and Myocardial Fibrosis in Athletes With Four-Dimensional Flow MRI.

Exercise-induced cardiac remodeling (CR) and myocardial fibrosis (MF) can increase cardiovascular risk in athletes. Early detection of pulmonary arterial hemodynamics parameters among athletes may be beneficial in optimizing the frequency of clinical follow-ups. To analyze the hemodynamics of pulmonary arteries and its relationship with CR and MF in athletes using four-dimensional (4D) flow MRI. Prospective. One hundred twenty-one athletes (median age, 24 years; mean exercise per week 10 hours, for mean of 5 years) and twenty-onesedentary healthy controls (median age, 25 years; exercise per week <3 hours, irregular pattern). True fast imaging with steady state free precession, time-resolved 3D Cartesian phase-contrast, and phase sensitive inversion recovery late gadolinium enhancement sequences at 3.0 T. CR was defined as any cardiac parameters exceeding the 99th percentile upper reference limits, encompassing ventricular function, bi-atrium and bi-ventricle diameters, and ventricular wall thickness. MF was visually evaluated by three independent radiologists. 4D flow parameters were assessed in the main, right, and left pulmonary arteries (MPA, RPA, and LPA, respectively) and compared between different groups. Four machine learning (ML) models were developed to differentiate between athletes with and without CR and/or MF. Univariate analysis was used to compare groups. Area under the receiver operating characteristic curve (AUC) was used to assess the performance of the ML models. Athletes had significantly higher WSSmax in the MPA, RPA, and LPA than controls. Athletes with CR and/or MF (N = 30) had significantly lower RPmax from MPA to RPA than those without (N = 91). Among the ML models, the gradient boosting machine model had the highest performance, with an AUC of 0.90. The pulmonary arterial hemodynamics parameters could differentiate CR and/or MF in athletes, which may be potential to assist in optimizing frequency of follow-up. 1 TECHNICAL EFFICACY: Stage 2.

Prognostic value of myocardial scar in ischaemic and non-ischaemic cardiomyopathy using cardiac magnetic resonance imaging.

The aim of this research was to evaluate the prognostic value of myocardial scar using cardiac magnetic resonance (CMR) imaging in patients with ischaemic cardiomyopathy (ICM) and non-ischaemic cardiomyopathy (NICM). One hundred and fifty-four patients with either ICM or NICM underwent CMR with late gadolinium enhancement sequences for assessment of left ventricular ejection fraction (LVEF), and detection and quantification of any myocardial scar using three methods: manual, number of segments involved, and percentage of scarred myocardium. Patients were followed up for at least six months for clinical cardiac events. Patients were divided into two groups: group I, patients with ICM (58%) and group II, those with NICM (42%). Clinical presentation ranged from eventless lpar;10%) to chest pain (18%), heart failure (15%), hospitalisation (35%), syncope (1%), ventricular tachycardia (< 1%) and cardiac arrest (< 1%). The scar mass was larger in size in group I (17 ± 15%) than in group II (8 ± 13%). A direct relationship was observed between scar size and event severity (p < 0.001). An inverse relationship between LVEF and event severity was found in group I (p < 0.001) but not in group II (p = 0.128). Myocardial scar size was a strong predictor of clinical outcome in both the ICM and NICM patients. LVEF was less reliable in predicting morbidity in cardiomyopathy patients.

Remodeling in Aortic Stenosis With Reduced and Preserved Ejection Fraction: Insight on Motion Abnormality Via 3D + Time Personalized LV Modeling in Cardiac MRI.

Increased afterload in aortic stenosis (AS) induces left ventricle (LV) remodeling to preserve a normal ejection fraction. This compensatory response can become maladaptive and manifest with motion abnormality. It is a clinical challenge to identify contractile and relaxation dysfunction during early subclinical stage to prevent irreversible deterioration. To evaluate the changes of regional wall dynamics in 3D + time domain as remodeling progresses in AS. Retrospective. A total of 31 AS patients with reduced and preserved ejection fraction (14 AS_rEF: 7 male, 66.5 [7.8] years old; 17 AS_pEF: 12 male, 67.0 [6.0] years old) and 15 healthy (6 male, 61.0 [7.0] years old). 1.5 T Magnetic resonance imaging/steady state free precession and late-gadolinium enhancement sequences. Individual LV models were reconstructed in 3D + time domain and motion metrics including wall thickening (TI), dyssynchrony index (DI), contraction rate (CR), and relaxation rate (RR) were automatically extracted and associated with the presence of scarring and remodeling. Shapiro-Wilk: data normality; Kruskal-Wallis: significant difference (P < 0.05); ICC and CV: variability; Mann-Whitney: effect size. AS_rEF group shows distinct deterioration of cardiac motions compared to AS_pEF and healthy groups (TIAS_rEF : 0.92 [0.85] mm, TIAS_pEF : 5.13 [1.99] mm, TIhealthy : 3.61 [1.09] mm, ES: 0.48-0.83; DIAS_rEF : 17.11 [7.89]%, DIAS_pEF : 6.39 [4.04]%, DIhealthy : 5.71 [1.87]%, ES: 0.32-0.85; CRAS_rEF : 8.69 [6.11] mm/second, CRAS_pEF : 16.48 [6.70] mm/second, CRhealthy : 10.82 [4.57] mm/second, ES: 0.29-0.60; RRAS_rEF : 8.45 [4.84] mm/second; RRAS_pEF : 13.49 [8.56] mm/second, RRhealthy : 9.31 [2.48] mm/second, ES: 0.14-0.43). The difference in the motion metrics between healthy and AS_pEF groups were insignificant (P-value = 0.16-0.72). AS_rEF group was dominated by eccentric hypertrophy (47.1%) with concomitant scarring. Conversely, AS_pEF group was dominated by concentric remodeling and hypertrophy (71.4%), which could demonstrate hyperkinesia with slight wall dyssynchrony than healthy. Dysfunction of LV mechanics corresponded to the presence of myocardial scarring (54.9% in AS), which reverted the compensatory mechanisms initiated and performed by LV remodeling. The proposed 3D + time modeling technique may distinguish regional motion abnormalities between AS_pEF, AS_rEF, and healthy cohorts, aiding clinical diagnosis and monitoring of AS progression. Subclinical myocardial dysfunction is evident in early AS despite of normal EF. 4 TECHNICAL EFFICACY: Stage 1.

Multimodality Imaging Evaluation to Detect Subtle Right Ventricular Involvement in Patients with Acute Myocarditis and Preserved Left Ventricular Ejection Fraction

Background: Evaluation of the right ventricle (RV) in patients with acute myocarditis (MY) remains challenging with both 2D transthoracic echocardiography (TTE) and cardiovascular magnetic resonance (CMR). We examined the incremental diagnostic value of CMR feature tracking (FT) to evaluate RV involvement in patients with myocarditis. Methods: We enrolled 54 patients with myocarditis and preserved left ventricle (LV) ejection fraction (EF). The CMR protocol included T2-weighted images for edema detection and late gadolinium enhancement (LGE) images. Global longitudinal strain (GLS) of the left ventricle (LV) and RV free wall strain (CMR-FWS) were obtained with CMR-FT. We identified 34 patients (62%) with inferior and lateral segment (IL-MY) involvement and 20 (38%) noIL-MY in case of any other myocardial segment involved. Here, 20 individuals who underwent CMR for suspected cardiac disease, which was not confirmed thereafter, were considered as the control population. Results: TTE and CMR showed normal RV function in all patients without visible RV involvement at the LGE or T2-weighted sequences. At CMR, LV-GLS values were significantly lower in patients with MY compared to the control group (median −19.0% vs. −21.0%, p = 0.029). Overall, CMR RV-FWS was no different between MY patients and controls (median −21.2% vs. −23.2 %, p = 0.201) while a significant difference was found between RV FWS in IL-MY and noIL-MY (median −18.17% vs. −24.2%, p = 0.004). Conclusions: CMR-FT has the potential to unravel subclinical RV involvement in patients with acute myocarditis, specifically in those with inferior and lateral injuries that exhibit lower RV-FWS values. In this setting, RV deformation analysis at CMR may be effectively implemented for a comprehensive functional assessment.

Cardiac magnetic resonance for prophylactic implantable-cardioverter defibrillator therapy international registry: prognostic value of LGE distribution in non-ischemic dilated cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): This work was supported by Italian Ministry of Health, Rome, Italy (RC 2017 R659/17-CCM698). Background/Introduction Tissue characterization obtained by cardiac magnetic resonance (CMR) has emerged as a promising tool for better identification of non ischemic cardiomyopathy patients at high arrhythmic risk and thus worthy of prophylactic ICD therapy. Purpose Current analysis has the scope to assess the prognostic value of fibrosis, as evaluated by late gadolinium enhancement sequences (LGE) specifically regarding its LV wall distribution, and a CMR-derived risk score. The primary endpoint was all-cause mortality. The secondary end-point consisted of major adverse arrhythmic cardiac events (MAACE), defined as combination of SCD, aborted SCD, and sustained ventricular tachycardia Methods DERIVATE Study is an international, multicenter, prospective, observational registry including consecutive patients from 21 sites referred for heart failure (HF) work-up including transthoracic echocardiography (TTE) and CMR without a history of previous major ventricular arrhythmias. Inclusion criteria were: (i) aged 18 or older, (ii) chronic HF, and (iii) LV-EF&amp;lt;50% at initial TTE. All patients underwent TTE and CMR within 3 months. Patients with (i) decompensated within 3 months of enrollment, (ii) recent myocardial infarction (&amp;lt;40 days), (iii) unstable angina, (iv) severe valvular disease, (v) primary or secondary cardiomyopathies other than NICM, (vi) cardiac amyloidosis, and (vii) congenital heart disease were excluded. Results The entire cohort consisted of 1384 subjects [mean age: 56±14 years, male: 948 (68.4%)]. The median follow-up time was 959 days. Mortality and MAACE occurred in 92 (6.6%) and 125 (9%) patients, respectively. SCD, aborted SCD, and sustained VT occurred in 15 (1.1%), 80 (5.8%), and 104 (7.5%), respectively. The sum of events exceeds the overall number of MAACE because several events could occur in the same patients but just the first event was counted. In the multivariate analyses for all-cause mortality, only the number of segments with LGE at the level of the septum was an independent predictor (p = 0.002), while in the analyses for MAACE the only independent predictors were male gender, LVEDVi by CMR, and the number of segments with LGE at the level of septum inferior. Based on the multivariate analysis, the DERIVATE score (including all 1384 patients) ranging from 0 to 8 (Cox regression analysis HR=1.35, 95%CI 1.24–1.46, p&amp;lt; 0.001) was realized. The redistribution of patients according to the CMR composite DERIVATE risk/year MAACE was of 44%, 37% and 32% for the low, intermediate and high risk groups, respectively. Conclusions The arrhythmic risk of patients with NICM is also dependent on the different distribution of fibrosis in the LV. The redistribution of the event rate according to the CMR composite risk score indicates the potential to alter the decision on ICD implantation in a relevant portion of NICM patients. These results warrant further confirmation in prospective randomized controlled trials.

A reduction of left ventricular global longitudinal strain (LV GLS) assessed with speckle tracking echocardiography (STE) predicts myocardial fibrosis in transfusion dependent beta-thalassemia

Abstract Funding Acknowledgements Type of funding sources: None. Background Cardiac involvement is common and the leading cause of death in transfusion dependent beta-thalassemia (TDT) patients. It is mainly related with cardiac iron overload and myocardial fibrosis, leading to a progressive cardiac damage which evolves towards a severe deterioration of systo-diastolic cardiac function. Moreover, myocardial fibrosis may not be directly related with the degree of cardiac iron deposition and it is associated with a high risk of cardiovascular complications. To date, Cardiac Magnetic Resonance (CMR) is the gold standard for the evaluation of iron overload with T2* sequences and for the detection of myocardial fibrosis with late gadolinium enhancement (LGE). However, CMR is not always feasible. Left Ventricular Global Longitudinal Strain (LV GLS) with Speckle Tracking Echocardiography (STE) is a non-invasive imaging tool, which may play a key role in the early recognition of subclinical myocardial damage and dysfunction (figure 1). This may help clinicians in guiding the diagnostic algorithm and the therapeutic approach. Purpose The aim of this study was the evaluation of the role of LV GLS with STE in the characterization of myocardial involvement in a population of TDT patients. Methods An observational, cross-sectional, monocentric study was conducted by the enrollment of 38 patients with TDT from the outpatient clinic of hematology of our hospital. Each patient underwent a thorough clinical evaluation including laboratory testing, transthoracic echocardiogram (TTE) with LV GLS-STE and contrast enhanced CMR with T2* technique and LGE sequences. A T2* value &amp;lt; 20 msec was set to define the presence of iron overload. Results The mean age of patients was 38 ± 10 years with a slight prevalence of female sex (53% vs 47% respectively). Cardiovascular risk factors were rarely present, the most common was arterial hypertension in about 12% of patients. The TTE pointed out a left ventricular ejection fraction within the normal range (mean value of 59 ± 5%). As regards LV GLS, the mean value was −19,8 ± 2,9%. Cardiac iron overload was observed in 18% of patients, while about 15% of patients had cardiac fibrosis. A mild clinical but not statistically significant difference was observed between LV GLS values in patients with cardiac iron overload as compared to patients without (−18,3 ± 2,3% vs −20,1 ± 3,0%; p value=0,147). A statistically significant difference was documented between LV GLS values in patient with cardiac fibrosis as compared to patient without LGE (−16.4 ± 1.7% vs −19,8 ± 2,4%; p value=0,004). A LV GLS cut-off value of −18,3% was found by the analysis of ROC curve with an AUC of 0,904 (95% CI: 0,798–1,000) (figure 2). Conclusions In a small population of TDT patients we observed that LV GLS with STE may be a promising tool in the early identification of cardiac damage to provide useful informations for diagnostic and therapeutic approach.

Increased hepatic T1 values are correlated with right ventricular involvement and congestion after ST-segment elevation myocardial infarction

Abstract Funding Acknowledgements Type of funding sources: None. Background ST-segment elevation myocardial infarction (STEMI) may have a multiorgan impact. Due to its proximity to the heart, a large portion of the liver is imaged during T1 mapping in Cardiovascular Magnetic Resonance (CMR) and recently higher T1 have been found associated with signs of right heart failure (RHF) in patients with non-ischemic cardiomyopathy, but no data are available in STEMI population. Purpose To evaluate the role of early hepatic native T1 in detecting the presence of right ventricle (RV) involvement after STEMI. Methods 133 patients with STEMI who underwent early CMR after primary angioplasty (PPCI) were enrolled. Patients with known hepatic disease were excluded from the study. Hepatic T1 was evaluated considering the mean value obtained from three regions of interest, free from fat and blood vessels. RV involvement was diagnosed in the presence of RV ejection fraction (EF) reduction according to current guidelines, RV wall motion abnormalities and the presence of necrosis in late gadolinium enhancement (LGE) sequences. Results Overall, the mean age was 59.72 ± 13.32 years and 28.2% were female. Fifty-two (39.1%) patients had an anterior myocardial infarction. The median time from PPCI to CMR was 3 [IQR 2.00–5.00] days. T1 mapping was available in all patients and mean hepatic T1 value of the population was 622.91 ± 100.14 ms. According to the Youden index the optimal hepatic T1 cut-off value to predict RV involvement was 605 ms. A total of 72 (54.1%) patients presented high hepatic T1 values (&amp;gt;605 ms). No significant correlations were found between high hepatic T1 values and left ventricle EF, infarct size, area at risk and the presence of microvascular obstruction. High hepatic T1 values were correlated with larger RV end-diastolic volume index (RVEDVi) (median 83.03 ml/m2 vs 53.16 ml/m2, p&amp;lt;0.001), lower RVEF (median 39.4% vs 57.62%, p&amp;lt;0.001) and presence of LGE in RV (26.5% vs 9.8%, p = 0.015). White blood cells (WBC), C-reactive protein and hs-Tn T peak values did not differ in the two study groups but NT-proBNP values were significantly higher in patients with high hepatic T1 (median 3531.22 vs 111.25 pg/mL, p&amp;lt;0.001). A strong positive correlation was found between hepatic T1 and NTproBNP (r = 0.754, p&amp;lt;0.001, Figure 1). At the univariable analysis, RV EF (OR 0.848, 95%CI 0.806–0.893, p&amp;lt;0.001), RVEDVi (OR 1.026, 95%CI 1.013–1.038, p&amp;lt;0.001) and the presence of RV infarct at the CMR evaluation (OR 3.286, 95%CI 1.218–8.865, p = 0.019) were found predictors of high hepatic T1 values. On multivariable logistic regression, RVEDVi (OR 1.022, 95%CI 1.006–1.038, p = 0.008) and RV-EF (OR 0.854, 95%CI 0.809–0.902, p&amp;lt;0.001) resulted as independent predictors of increased hepatic T1 values. Conclusions RV involvement after STEMI may lead to hepatic congestion and high hepatic T1 values are associated with early RV dysfunction parameters (RVEDVi, RV-EF and LGE) at CMR and higher levels of NT-proBNP.

CMR reclassifies patients with suspected myocardial infarction with non-obstructive coronary arteries (MINOCA)

Abstract Funding Acknowledgements Type of funding sources: None. Objectives This study sought to assess the role of cardiac magnetic resonance (CMR) in investigating patients presenting with suspected acute coronary syndrome (ACS) and non-obstructed coronary arteries. Methods Consecutive patients presenting to a tertiary cardiology centre with suspected ACS and non-obstructed coronary arteries and referred for CMR were retrospectively identified. A comprehensive imaging protocol was performed to include cines, T2-weighted, and late gadolinium enhancement (LGE) sequences. Final CMR diagnosis was based on established patterns of tissue characterisation from myocardial oedema and LGE imaging, with patients grouped into five: myocardial infarction, myocarditis, Takotsubo syndrome, cardiomyopathy, and a normal CMR. Results A total of 888 patients were identified. The mean age across the cohort was 57 years (SD ±15.9 years) with 51% female patients. Median time to CMR from acute presentation was 21 days (Figure 1). Aetiology of presentation was uncertain in more than half of patients referred for CMR (483, 54.1%). Of patients with an initial uncertain aetiology, CMR was able to identify an underlying diagnosis in 74.9%. Diagnosis across the whole cohort was reclassified in 691 patients (77.8%), with overall diagnostic yield (CMR identified underlying aetiology for presentation) of 75.6%. (Figure 2). Conclusions In a large single-centre cohort of patients presenting with suspected ACS and non-obstructed coronary arteries, diagnostic yield with CMR was high at 76%. CMR reclassified nearly 80% of patients. Our results highlight the importance of CMR in the diagnostic pathway of suspected ACS and potential implications on clinical management.

Multimodality Imaging of Cardiac Angiolipoma

HomeRadiologyVol. 307, No. 5 PreviousNext Reviews and CommentaryFree AccessImages in RadiologyMultimodality Imaging of Cardiac AngiolipomaSimin Lin, Haojun Chen Simin Lin, Haojun Chen Author AffiliationsFrom the Department of Radiology, Xiamen Cardiovascular Hospital of Xiamen University, School of Medicine, Xiamen University, No. 2999 Jinshan Rd, Xiamen 361006, China (S.L.); and Department of Nuclear Medicine & Minnan PET Center, First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China (H.C.).Address correspondence to H.C. (email: [email protected]).Simin LinHaojun Chen Published Online:Jun 13 2023https://doi.org/10.1148/radiol.230116MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In A 39-year-old man presented with a history of abdominal pain for 2 months. A routine chest radiograph showed an increased cardiothoracic ratio, and US was subsequently performed. At transthoracic echocardiography, an isoechoic cardiac mass was incidentally found in the anterior wall of the right atrium. The patient had no symptoms of chest tightness, chest pain, or dyspnea. His tumor markers showed a mild elevation of cancer antigen 125 (36.50 U/mL) and cancer antigen 724 (14.98 U/mL). The patient was scheduled for cardiac MRI to further characterize the lesion. A static four-chamber view obtained with a steady-state free precession sequence showed a 7.3 × 4.0-cm mass with heterogeneous signal intensity in the right atrium and atrioventricular groove (Figure, A). First-pass perfusion imaging indicated no apparent perfusion in the mass, which encased the right coronary artery (Figure, B). Inhomogeneous enhancement was detected with late gadolinium enhancement sequences (Figure, C), raising suspicion for malignancy. Hence, correlative fluorine 18 (18F) fluorodeoxyglucose (FDG) PET/CT was performed for tumor staging. Axial PET/CT images (Figure, D) revealed areas of fat attenuation and low 18F-FDG uptake, yielding a tumor-to-background ratio of 1:1. No abnormal radioactivity was observed in the extracardiac areas. The patient subsequently underwent radical tumor resection and surgical reconstruction of the right atrium. Histopathologic workup showed adipose tissue and interspersed proliferating blood vessels, consistent with the diagnosis of cardiac angiolipoma.(A) Cardiac MRI scan obtained with steady-state free precession (SSFP) shows a soft-tissue mass with heterogeneous signal intensity in the right atrium and atrioventricular groove (arrow). (B) First-pass perfusion MRI scan shows the mass encasing the right coronary artery (coronary vessel floating sign) without evident perfusion (arrowheads). (C) Short-axial late gadolinium enhancement (LGE) MRI scan shows inhomogeneous enhancement of the mass (arrow). (D) Axial fluorine 18 (18F) fluorodeoxyglucose (FDG) PET/CT image reveals areas of fat attenuation and mild 18F-FDG uptake (arrow) within the lesion (maximum standardized uptake value, 2.9), with a tumor-to-background ratio of 1:1.Download as PowerPointOpen in Image Viewer Disclosures of conflicts of interest: S.L. No relevant relationships. H.C. No relevant relationships.Article HistoryReceived: Jan 17 2023Revision requested: Feb 15 2023Revision received: Feb 17 2023Accepted: Mar 10 2023Published online: June 13 2023 FiguresReferencesRelatedDetailsRecommended Articles Dissection of a Giant Coronary AneurysmRadiology: Cardiothoracic Imaging2023Volume: 5Issue: 1Multimodality Imaging of Transposition of the Great ArteriesRadioGraphics2021Volume: 41Issue: 2pp. 338-360Fibrous Skeleton of the Heart: Anatomic Overview and Evaluation of Pathologic Conditions with CT and MR ImagingRadioGraphics2017Volume: 37Issue: 5pp. 1330-1351Cinematic Rendering of Complex Coronary Artery Left Atrial FistulaRadiology2022Volume: 307Issue: 1Active Cardiac Sarcoidosis Imitating Cardiac MetastasesRadiology: Cardiothoracic Imaging2020Volume: 2Issue: 6See More RSNA Education Exhibits Pearls and Pitfalls in Cardiac ImagingDigital Posters2022Multimodal Imaging Characterization of Cardiac Tumors Emphasizing PET with Pathology Correlation Using the New 2021 WHO ClassificationDigital Posters2022Mulmodality Imaging of Atrioventricular Groove Masses - Diagnostic ApproachDigital Posters2022 RSNA Case Collection Cardiac metastasis from melanomaRSNA Case Collection2022Cardiac myxomaRSNA Case Collection2020Primary Cardiac ParagangliomaRSNA Case Collection2022 Vol. 307, No. 5 Metrics Altmetric Score PDF download

PO-03-092 MACHINE LEARNING ANALYSIS OF THE PREDICTORS OF AF RECURRENCE POST-ABLATION IN PATIENTS UNDERGOING PRE-ABLATION MRI

Catheter ablation, a widely performed rhythm control strategy for atrial fibrillation (AF), has variable results in the complete suppression of arrhythmia recurrence, especially in obese patients. Structural remodeling of the left atrium (LA), evidenced by LA enlargement and fibrosis, is a well-known substrate for AF. Epicardial adipose tissue (EAT) is thought to be a crucial factor mediating cardiovascular disease in obesity, it can result in electrical heterogeneity and local conduction block forming a substrate for AF. We aimed to apply a machine learning approach to assess the predictors of AF recurrence following catheter ablation in AF patients undergoing pre-ablation cardiac magnetic resonance (CMR). 101 AF patients underwent CMR prior to catheter ablation. Fibrotic remodeling was assessed using the late gadolinium enhancement sequence. EAT was assessed using the novel fat-water separation 3D Dixon sequence. Panel A shows posterior and anterior views of a representative LA model showing fibrotic remodeling and EAT. Patients were followed for AF recurrence using ambulatory monitoring and 12-lead ECGs. A random forest classifier with 5x stratified cross-validation was trained to predict AF recurrence post-ablation and SHapley Additive exPlanations (SHAP) analysis was used to assess feature importance in the prediction of AF recurrence. During an average follow-up period of 1 year, post-ablation AF recurrence occurred in 31 (30.7%) patients. Patients with AF recurrence post-ablation had higher LA EAT index (20.7 [16.9, 30.4] vs 13.7 [10.5, 20.1] mL/m2, p<0.001), and higher LA volume index (66 [52.6, 77.5] vs 49.9 [37.7, 61.8] mL/m2, p=0.001). There was a trend toward a higher fibrosis burden in patients who had an AF recurrence (18.6% vs 16.1%, p=0.076). The classifier predicted AF recurrence post-ablation with an AUC of 0.67 ± 0.09 (Panel B). SHAP analysis revealed that for the overall population, the three most important features in the prediction of AF recurrence post-ablation were LA volume index, LA EAT index, and LA fibrosis (Panel C). LA enlargement, fibrosis and EAT, markers with clear ties to AF pathophysiology, are predictors of AF recurrence after ablation. Future studies testing the value of an imaging-based ablation failure prediction calculator, as well as studies to elucidate the mechanism of ablation failure, are required.

PO-03-139 HIGH-RESOLUTION CARDIAC MAGNETIC RESONANCE IMAGING FOR LEFT ATRIAL APPENDAGE SIZING AND THROMBUS EXCLUSION PRIOR TO DEVICE CLOSURE

Transesophageal echocardiography and cardiac computed tomography angiography are currently utilized for left atrial appendage closure (LAAC) planning. The advent of high-resolution cardiac magnetic resonance imaging (HR-CMR) now potentially allows for adequate spatial resolution for LAAC planning. This study sought to assess preoperative HR-CMR with software-based sizing vs intraoperative TEE for LAA sizing and thrombus exclusion prior to LAAC. This retrospective study conducted at The Ohio State University Wexner Medical Center included all patients who underwent preoperative HR-CMR and intraoperative TEE for LAAC with Watchman FLX (Boston Scientific, Marlborough, MA) from May to September 2022. For HR-CMR, magnetic resonance angiography (MRA) and late gadolinium enhancement (LGE) sequences were obtained for LAA sizing and thrombus exclusion respectively. A proprietary sizing software (TruPlan, Boston Scientific) was utilized to analyze the MRA sequence to characterize LAA anatomy, predict closure device size, and estimate device compression ratio. HR-CMR was compared to TEE for assessing accuracy of LAA thrombus exclusion, maximum ostial diameter, depth, lobe count, morphology, and accuracy of predicted device size. 16 patients were included, with baseline characteristics notable for 8 (50%) females, age 73 ± 6 years, 30 ± 7 kg/m2 body mass index, 54 ± 8% left ventricular ejection fraction, and 4 ± 2 CHA2DS2-VASc. 15 (94%) cases were successfully completed. There was no significant difference in LAA thrombus exclusion (CMR 14 (88%) vs TEE 16 (100%) cases, p=0.48), maximum ostial diameter (CMR 20.9 ± 4.2 vs TEE 20.6 ± 4.2 mm, p=0.99), depth (CMR 31.1 ± 7.8 vs TEE 26.8 ± 5.6 mm, p=0.09), lobe count (CMR 1.8 ± 0.8 vs TEE 1.4 ± 0.6 lobes, p=0.25), and morphology features (p=0.44). LAA assessments are summarized in Table I. The mean devices deployed per case was 1.1 ± 0.3. In 2 (13%) cases a device downsize was required. 1 case was aborted due to inability to access a very small LAA ostium. On 45-day TEE or CCTA, no peri-device leak ≥5 mm or device-related thrombus were noted. A comparison of standard vs high-resolution contrast-enhanced (CE)-MRA of the LAA is demonstrated in Figure 1. HR-CMR is a viable modality for preoperative LAA sizing and thrombus exclusion with promising results. HR-CMR may provide utility in cases where TEE or CCTA are contraindicated or unavailable.Tabled 1Table IMeasureHR-CMR (N=16)TEE (N=16)P-valueLAA thrombus accurately excluded14 (88%)16 (100%)0.484Minimum LAA ostial diameter (mm)18.0 ± 4.216.6 ± 3.40.335Target LAA ostial diameter (mm)*20.9 ± 4.220.6 ± 4.20.987LAA depth (mm)31.1 ± 7.826.8 ± 5.60.093Number of lobes1.8 ± 0.81.4 ± 0.60.250Morphology0.437Cactus4 (25%)3 (19%)Cauliflower0 (0%)2 (13%)Chicken wing5 (31%)2 (13%)Windsock7 (44%)8 (50%)Other0 (0%)1 (6%)LAA closure device size accurately predicted12 (75%)12 (75%)1.000Values presented as mean ± 1 standard deviation for continuous variables and n (%) for categorical variables. Abbreviations: HR-CMR = high resolution cardiac magnetic resonance imaging, LAA = left atrial appendage, TEE = transesophageal echocardiography. *Based on maximum diameter measured on TEE vs area-derived diameter on HR-CMR. Open table in a new tab

MR guided cardiac ablation: how to build an interventional magnetic resonance suite and what's the role of the imaging.

Magnetic resonance (MR) represents a new interesting imaging approach for guiding electrophysiology (EP)-based ablation procedures of atrial flutter and typical atrial fibrillation. This new approach permits to reach good results if compared with conventional EP ablation. Tissue characterization by MR permits to detect cardiac anatomy and pathological substrate like myocardial scars well visualized with late gadolinium enhancement (LGE) sequences. Intra-procedural imaging is useful to real-time follow the catheter during the ablation procedure and at the same time to visualize cardiac anatomy in addition to understanding if the ablation is correctly performed using oedema sequences. Performing cardiac ablations inside an MR room permits to reduce radiation exposure and occupational illnesses.

The evolving role of cardiovascular magnetic resonance in the assessment of mitral valve prolapse.

Mitral valve prolapse (MVP), characterized by a displacement > 2 mm above the mitral annulus of one or both bileaflets, with or without leaflet thickening, is a common valvular heart disease, with a prevalence of approximately 2% in western countries. Although this population has a generally good overall prognosis, MVP can be associated with mitral regurgitation (MR), left ventricular (LV) remodeling leading to heart failure, ventricular arrhythmia, and, the most devastating complication, sudden cardiac death, especially in myxomatous bileaflet prolapse (Barlow's disease). Among several prognostic factors reported in the literature, LV fibrosis and mitral annular disjunction may act as an arrhythmogenic substrate in this population. Cardiac magnetic resonance (CMR) has emerged as a reliable tool for assessing MVP, MR severity, LV remodeling, and fibrosis. Indeed, CMR is the gold standard imaging modality to assess ventricular volume, function, and wall motion abnormalities; it allows accurate calculation of the regurgitant volume and regurgitant fraction in MR using a combination of LV volumetric measurement and aortic flow quantification, independent of regurgitant jet morphology and valid in cases of multiple valvulopathies. Moreover, CMR is a unique imaging modality that can assess non-invasively focal and diffuse fibrosis using late gadolinium enhancement sequences and, more recently, T1 mapping. This review describes the use of CMR in patients with MVP and its role in identifying patients at high risk of ventricular arrhythmia.