Late Gadolinium Enhancement Sequences Research Articles

Cardiovascular magnetic resonance 3D LGE imaging for atrial fibrillation ablation

Abstract Objective To assess feasibility and reliability of cardiac magnetic resonance (CMR) imaging in visualizing left atrial (LA) structural changes that patients with paroxysmal atrial fibrillation (PAF) undergo acutely and long-term post ablation. Two different ablation methods i.e pulsed filed ablation (PFA) and cryoablation were studied. Background Pulmonary vein (PV) isolation has become the cornerstone technique for catheter ablation in patients with drug-refractory atrial fibrillation (AF). At present, almost all ablation technologies are mediated by a thermal effect. Recently, pulsed field ablation (PFA) has been introduced as a new energy source. PFA is a non-thermal ablative modality in which high voltage ultra-short pulses are applied to target tissue, while preserving the extracellular matrix architecture, nerves, and microvascular structures. Few data exist showing different structural LA changes between the two methods using Three-Dimensional (3D) Late Gadolinium Enhancement (LGE) Imaging. Methods CMR imaging was performed pre-ablation, acutely (<24 h), and 3 months post-ablation in 10 patients with paroxysmal atrial fibrillation (AF) undergoing pulmonary vein (PV) isolation with PFA (n = 5) or cryoablation (n = 5). 3D LGE and T2-weighted images were analysed. We obtained two data sets of 3D whole heart LGE imaging with high resolution, 20minutes post gadolinium injection. Patients underwent two acquisitions: the conventional respiratory navigated, electrocardiographically-gated 3D fast gradient echo (1.3slice thickness, 256x256 matrix acquisition) and the image-navigated isotropic high resolution 3D LGE with Dixon water-fat separation. 3D LGE data were analysed using a dedicated (ADAS LA) software in order to produce a 3D-LA model visualization of LGE areas. Results In the acute stage, LGE volume was 50% larger after PFA vs. cryoablation (P < 0.001), and oedema on T2 imaging was significantly smaller (visual estimation) on PFA cases. LGE rings surrounding PV ostia were more homogeneous after PFA, with no sign of microvascular damage or intramural hemorrhage as compared to cryoablation cases. In the chronic stage, the majority of acute LGE had disappeared after PFA, whereas most LGE persisted after cryo-ablation. The two 3D LGE sequences used for analysis showed complete agreement in the visualization of atrial scar with superior image quality of the novel sequence. The mean acquisition time for 3D LGE imaging was 11±4minutes for the conventional fast gradient echo sequence, and 5±2minutes for the novel 3D self-image navigated LGE sequence. Conclusions CMR imaging may help in visualization and understanding of LA structural remodeling post different ablation techniques.

Cardiac magnetic resonance - aided ventricular tachycardia substrate ablation

Abstract Objectives To assess feasibility and reliability of Cardiac magnetic resonance (CMR)-derived pixel signal intensity (PSI) maps obtained by Three Dimensional (3D)- Late Gadolinium Enhancement (LGE) images for detecting potential targets for VT substrate ablation procedures. Background Parametric imaging with color-coded PSI maps obtained from pre-ablation 3D LGE -CMR imaging can be used for identification and characterization of arrhythmic abnormal substrate. Recent publications have shown that PSI maps permit visualization of border zone areas inside the scar. Specifically, corridors of viable tissue within the scar connecting healthy myocardium define VT corridors that may be the electrical equivalent of the abnormal conducting channels on the electroanatomical mapping (EAM). Methods 8 patients with scar-dependent monomorphic VTs who underwent 3D-LGE CMR imaging prior to substrate ablation were included in the study. The studies were performed at 1.5T scanner. We obtained two data sets of 3D whole heart LGE imaging with high resolution. Patients underwent two acquisitions: the conventional respiratory navigated, electrocardiographically-gated 3D fast gradient echo (1.3slice thickness, 256x256 matrix acquisition) and the image-navigated isotropic high resolution 3D GE with Dixon water-fat separation. 3D LGE-CMR images were processed with ADAS-VT software to produce a 3-dimensional model of the heart with 10 layers from the endocardium to epicardium and PSI maps color-coded from the LGE data projected to each of the shells (Figure 1). In the LGE-CMR PSI maps, VT corridors were obtained automatically by the ADAS VT software. Subsequently, data were given to the electrophysiologists and merged with the CARTO3 system EAM data obtained for the ablation (Figure2). CMR information was used to facilitate the identification of target ablation sites in the areas identified by CMR as abnormal substrate and radiofrequency was applied in the presence of both a pathological electrogram (EGM) and a VT corridor as identified by CMR. Results There was a 95% agreement between the abnormal conducting channels as detected by abnormal electrograms in the EAM and the VT corridors identified by 3D LGE CMR imaging. In two occasions, there was one VT corridor that did not correlate with abnormal electrograms and was not ablated. The two 3D LGE sequences used for ADAS-VT corridors analysis showed complete agreement in the number and location of VT corridors. Mean acquisition time for 3D LGE imaging was 11±4minutes for the conventional fast gradient echo sequence, and 5±2minutes for the novel 3D self-image navigated LGE sequence. The image quality of 3D LGE was superior with the Dixon fat-water separation. Overall CMR-aided VT ablation reduced the procedural and fluoroscopy time by 40%. Conclusions CMR-aided VT ablation is feasible, reliable and significantly reduces the procedural time.

Incremental Prognostic Value of Left Atrial Strain in Patients With Suspected Myocarditis and Preserved Left Ventricular Ejection Fraction.

Analysis of left atrial (LA) strain and left atrioventricular coupling index (LACI) have prognostic value in cardiovascular diseases. However, the prognostic value of LA strain and LACI in patients with suspected myocarditis and preserved left ventricular ejection fraction (LVEF) is unclear. To investigate the prognostic value of LA strain and LACI in patients with suspected myocarditis and preserved LVEF in comparison with conventional MRI outcome predictors. Retrospective. One hundred sixty-five patients with clinically suspected myocarditis and preserved LVEF with available follow-up data. Steady-state free precession cine and phase-sensitive inversion recovery segmented gradient echo late gadolinium enhancement sequences at 3.0 T. Left ventricular (LV) and LA strain were evaluated using feature tracking. LACI was calculated as the ratio of LA and LV volumes at LV end-diastole. Patients were followed-up with the primary endpoint being major adverse cardiovascular events (MACE). Independent-samples t-test and Mann-Whitney U test to compare patients with and without MACE, receiver operating characteristic (ROC) curve analysis to define high/low risk groups, Kaplan-Meier survival analysis and Cox proportional hazards regression to assess prognosis. A P value of <0.05 was considered statistically significant. The associations of LV strain parameters (including global radial, circumferential, and longitudinal strain) and LACI with MACE were not significant (P = 0.511, 0.108, 0.148, and 0.847, respectively). An optimal LA conduit strain (Ԑe) cutoff value of 10.4% was identified to best classify patients into low- and high-risk groups. Only Ԑe was significantly associated with MACE in both univariable (hazards ratio [HR] 0.936, 95% confidence interval [CI] 0.884-0.991) and multivariable Cox survival analyses (HR 0.937, 95% CI 0.884-0.994). LA conduit strain has prognostic value in patients with suspected myocarditis and preserved LVEF, incremental to conventional MRI outcome predictors, whereas LACI was not associated with MACE occurrence. 3 TECHNICAL EFFICACY: Stage 2.

Subclinical myocardial involvement in a cohort of patients with antisynthetase syndrome.

There is an increasing interest in knowing whether patients with antisynthetase syndrome (ASSD) may have silent myocardial interstitial involvement. Mapping techniques in cardiac magnetic resonance (CMR) can detect subclinical myocardial involvement. The purpose of this study was to identify alterations in multiparametric CMR in ASSD patients without overt cardiac involvement. Patients diagnosed with ASSD underwent a CMR along with the standard clinical workup, investigation of specific and associated myositis antibodies, and high-resolution chest CT. The CMR protocol includes routine morphologic, functional, and late gadolinium enhancement sequences in standard cardiac planes, as well as native T1 and T2 mapping sequences and extracellular volume (ECV) calculation. Twenty-five patients were included in this study (56% women; median age 56.3 years). Three patients were considered in the acute phase at the time of inclusion. Eight patients (32%) showed pathological findings in CMR (6 stable disease, 2 acute phase). Elevated T1, T2 and ECV mapping values were found in 20% (5/25), 17% (4/25) and 24% (6/25) of the group, respectively. Two patients in the acute phase had increased values of both T2 and ECV. Subclinical myocardial involvement in ASSD is not rare (32%) although its clinical significance is uncertain. Myocardial oedema (T2) was the most frequent finding, followed by increased T1 and/or ECV values likely signalling interstitial fibrosis. Of note, patients in the acute phase showed elevated T2 values.

Evaluating a novel accelerated free-breathing late gadolinium enhancement imaging sequence for assessment of myocardial injury

IntroductionCardiac magnetic resonance imaging (MRI), including late gadolinium enhancement (LGE), plays an important role in the diagnosis and prognostication of ischemic and non-ischemic myocardial injury. Conventional LGE sequences require patients to perform multiple breath-holds and require long acquisition times. In this study, we compare image quality and assessment of myocardial LGE using an accelerated free-breathing sequence to the conventional standard-of-care sequence. MethodsIn this prospective cohort study, a total of 41 patients post Coronavirus 2019 (COVID-19) infection were included. Studies were performed on a 1.5 Tesla scanner with LGE imaging acquired using a conventional inversion recovery rapid gradient echo (conventional LGE) sequence followed by the novel accelerated free-breathing (FB-LGE) sequence. Image quality was visually scored (ordinal scale from 1 to 5) and compared between conventional and free-breathing sequences using the Wilcoxon rank sum test. Presence of per-segment LGE was identified according to the American Heart Association 16-segment myocardial model and compared across both conventional LGE and FB-LGE sequences using a two-sided chi-square test. The perpatient LGE extent was also evaluated using both sequences and compared using the Wilcoxon rank sum test. Interobserver variability in detection of per-segment LGE and per-patient LGE extent was evaluated using Cohen's kappa statistic and interclass correlation (ICC), respectively. ResultsThe mean acquisition time for the FB-LGE sequence was 17 s compared to 413 s for the conventional LGE sequence (P < 0.001). Assessment of image quality was similar between both sequences (P = 0.19). There were no statistically significant differences in LGE assessed using the FB-LGE versus conventional LGE on a per-segment (P = 0.42) and per-patient (P = 0.06) basis. Interobserver variability in LGE assessment for FB-LGE was good for per-segment (= 0.71) and per-patient extent (ICC = 0.92) analyses. ConclusionsThe accelerated FB-LGE sequence performed comparably to the conventional standard-of-care LGE sequence in a cohort of patients post COVID-19 infection in a fraction of the time and without the need for breath-holding. Such a sequence could impact clinical practice by increasing cardiac MRI throughput and accessibility for frail or acutely ill patients unable to perform breath-holding.

MRI Assessment of Myocardial Deformation for Risk Stratification of Major Arrhythmic Events in Patients With Non-Ischemic Cardiomyopathy Eligible for Primary Prevention Implantable Cardioverter Defibrillators.

Implantable cardioverter-defibrillator (ICD) intervention is an established prophylactic measure. Identifying high-benefit patients poses challenges. To assess the prognostic value of cardiac magnetic resonance imaging (MRI) parameters including myocardial deformation for risk stratification of ICD intervention in non-ischemic cardiomyopathy (NICM) while accounting for competing mortality risk. Retrospective and prospective. One hundred and fifty-nine NICM patients eligible for primary ICD (117 male, 54 ± 13 years) and 49 control subjects (38 male, 53 ± 5 years). Balanced steady state free precession (bSSFP) and three-dimensional phase-sensitive inversion-recovery late gadolinium enhancement (LGE) sequences at 1.5 T or 3 T. Patients underwent MRI before ICD implantation and were followed up. Functional parameters, left ventricular global radial, circumferential and longitudinal strain, right ventricular free wall longitudinal strain (RV FWLS) and left atrial strain were measured (Circle, cvi42). LGE presence was assessed visually. The primary endpoint was appropriate ICD intervention. Models were developed to determine outcome, with and without accounting for competing risk (non-sudden cardiac death), and compared to a baseline model including LGE and clinical features. Wilcoxon non-parametric test, Cox's proportional hazards regression, Fine-Gray competing risk model, and cumulative incidence functions. Harrell's c statistic was used for model selection. A P value <0.05 was considered statistically significant. Follow-up duration was 1176 ± 960 days (median: 896). Twenty-six patients (16%) met the primary endpoint. RV FWLS demonstrated a significant difference between patients with and without events (-12.5% ± 5 vs. -16.4% ± 5.5). Univariable analyses showed LGE and RV FWLS were significantly associated with outcome (LGE: hazard ratio [HR] = 3.69, 95% CI = 1.28-10.62; RV FWLS: HR = 2.04, 95% CI = 1.30-3.22). RV FWLS significantly improved the prognostic value of baseline model and remained significant in multivariable analysis, accounting for competing risk (HR = 1.73, 95% CI = 1.12-2.66). In NICM, RV FWLS may provide additional predictive value for predicting appropriate ICD intervention. 2 TECHNICAL EFFICACY: Stage 5.

Liver T1 Mapping Derived From Cardiac Magnetic Resonance Imaging: A Potential Prognostic Marker in Idiopathic Dilated Cardiomyopathy.

Hepatic alterations are common aftereffects of heart failure (HF) and ventricular dysfunction. The prognostic value of liver injury markers derived from cardiac MRI studies in nonischemic dilated cardiomyopathy (DCM) patients is unclear. Evaluate the prognostic performance of liver injury markers derived from cardiac MRI studies in DCM patients. Prospective. Three hundred fifty-six consecutive DCM patients diagnosed according to ESC guidelines (age 48.7 ± 14.2 years, males 72.6%). Steady-state free precession, modified Look-Locker inversion recovery T1 mapping and phase sensitive inversion recovery late gadolinium enhancement (LGE) sequences at 3 T. Clinical characteristics, conventional MRI parameters (ventricular volumes, function, mass), native myocardial and liver T1, liver extracellular volume (ECV), and myocardial LGE presence were assessed. Patients were followed up for a median duration of 48.3 months (interquartile range 42.0-69.9 months). Primary endpoints included HF death, sudden cardiac death, heart transplantation, and HF readmission; secondary endpoints included HF death, sudden cardiac death, and heart transplantation. Models were developed to predict endpoints and the incremental value of including liver parameters assessed. Optimal cut-off value was determined using receiver operating characteristic curve and Youden method. Survival analysis was performed using Kaplan-Meier and Cox proportional hazard. Discriminative power of models was compared using net reclassification improvement and integrated discriminatory index. P value <0.05 was considered statistically significant. 47.2% patients reached primary endpoints; 25.8% patients reached secondary endpoints. Patients with elevated liver ECV (cut-off 34.4%) had significantly higher risk reaching primary and secondary endpoints. Cox regression showed liver ECV was an independent prognostic predictor, and showed independent prognostic value for primary endpoints and long-term HF readmission compared to conventional clinical and cardiac MRI parameters. Liver ECV is an independent prognostic predictor and may serve as an innovative approach for risk stratification for DCM. 1 TECHNICAL EFFICACY: Stage 2.

Can native T1 mapping sequence be used as a non-invasive alternative imaging tool to LGE sequence for evaluating DCM patients?

BackgroundMyocardial fibrosis is the potential outcome of dilated cardiomyopathy (DCM). Cardiac MRI is considered one of the most essential imaging methods in DCM evaluation by using the late gadolinium enhancement (LGE) sequence and native T1 mapping technique. The study aimed to assess the diagnostic accuracy and reliability of the native T1 mapping technique for detecting myocardial fibrosis in DCM patients and correlate the values with the LGE in such a patient population.ResultsLGE was present in ten patients (33.33%) and 46 out of 480 myocardial segments (9.58%). T1 native values were significantly higher in the LGE group compared to the non-LGE group (P < 0.001). Furthermore, the non-LGE group showed higher T1 native values than the control group. Based on receiver operating characteristics (ROC) curves analysis, the best cut-off value of T1 native for the discrimination between normal myocardium and DCM was 1060 ms, while 1125 ms was the optimal cut-off value for LGE prediction among DCM patients (AUC; 0.919 and 0.904), respectively.ConclusionsNative T1 mapping technique can be used as a simple, practical, and reproducible method for characterizing myocardial fibrosis in patients with DCM with high diagnostic accuracy and specificity.

Kiosk 4R-TC-11 - Novel Image Navigator Based Isotropic 3D Late Gadolinium Enhancement Sequence Allows Differentiation of Healthy and Diseased Left Atrial Myocardium

Kiosk 4R-TC-11 - Novel Image Navigator Based Isotropic 3D Late Gadolinium Enhancement Sequence Allows Differentiation of Healthy and Diseased Left Atrial Myocardium

Novel implementation of cardiac magnetic resonance first-pass perfusion imaging for semi-quantitatively evaluating microvascular dysfunction in paediatric patients with Duchenne muscular dystrophy.

The current study aimed to assess myocardial microcirculation dysfunction via cardiac magnetic resonance (CMR) first-pass perfusion imaging in children with Duchenne muscular dystrophy (DMD). In total, 67 children with DMD and 15 controls who underwent contrast-enhanced CMR first-pass perfusion imaging were enrolled in this study. CMR first-pass perfusion and late gadolinium enhancement (LGE) sequences were acquired. Further, the global, regional, and coronary artery distribution area perfusion indexes (PI), upslope (%BL), maximum signal intensity (MaxSI), time to maximum signal intensity (TTM), and baseline SI were analysed. The perfusion parameters of the LGE positive (+), LGE negative (-), and control groups were compared. Pearson correlation analysis was performed to assess the association between myocardial microcirculation and conventional cardiac function and LGE parameters. The LGE+ group had a significantly lower global and apical-ventricular MaxSI than the control group (all P < .05). The left anterior descending arterial (LAD), left circumflex coronary arterial (LCX), and right coronary arterial (RCA) segments of the LGE+ group had a lower upslope and MaxSI than those of the control group (all P < .05). The LAD segments of the LGE- group had a lower MaxSI than those of the control group (41.10 ± 11.08 vs 46.36 ± 13.04; P < .001). The LCX segments of the LGE- group had a lower PI and upslope than those of the control group (11.05 ± 2.84 vs 12.46 ± 2.82; P = .001; 59.31 ± 26.76 vs 68.57 ± 29.99; P = .002). Based on the correlation analysis, the upslope, MaxSI, and TTM were correlated with conventional cardiac function and LGE extent. Paediatric patients with DMD may present with microvascular dysfunction. This condition may appear before LGE and may be correlated with coronary artery blood supply and LGE extent. First-pass perfusion parameters may reveal the status of myocardial microcirculation and reflect the degree of myocardial injury at an earlier time in DMD patients. Perfusion parameters should be analysed not only via global or base, middle, and apical segments but also according to coronary artery distribution area, which may detect myocardial microvascular dysfunction at an earlier stage, in DMD patients with LGE-.

Aligning Multi-Sequence CMR Towards Fully Automated Myocardial Pathology Segmentation.

Myocardial pathology segmentation (MyoPS) is critical for the risk stratification and treatment planning of myocardial infarction (MI). Multi-sequence cardiac magnetic resonance (MS-CMR) images can provide valuable information. For instance, balanced steady-state free precession cine sequences present clear anatomical boundaries, while late gadolinium enhancement and T2-weighted CMR sequences visualize myocardial scar and edema of MI, respectively. Existing methods usually fuse anatomical and pathological information from different CMR sequences for MyoPS, but assume that these images have been spatially aligned. However, MS-CMR images are usually unaligned due to the respiratory motions in clinical practices, which poses additional challenges for MyoPS. This work presents an automatic MyoPS framework for unaligned MS-CMR images. Specifically, we design a combined computing model for simultaneous image registration and information fusion, which aggregates multi-sequence features into a common space to extract anatomical structures (i.e., myocardium). Consequently, we can highlight the informative regions in the common space via the extracted myocardium to improve MyoPS performance, considering the spatial relationship between myocardial pathologies and myocardium. Experiments on a private MS-CMR dataset and a public dataset from the MYOPS2020 challenge show that our framework could achieve promising performance for fully automatic MyoPS.

Prediction of left ventricular thrombus after STEMI based on readily available clinical, echocardiographic and ECG variables

Abstract Background Left ventricular thrombus (LVTh) is an uncommon yet serious complication after ST-segment elevation myocardial infarction (STEMI). LVTh can be accurately detected in late gadolinium enhancement (LGE) sequences in cardiac magnetic resonance (CMR). However, selection of patients who should undergo this imaging technique for LVTh detection is not defined yet. Purpose We aim to stratify the risk of LVTh occurrence after STEMI by clinical, echocardiographic and ECG variables during admission and help select patients who should undergo CMR for LVTh detection. Methods Our registry comprised reperfused STEMI patients who underwent early (1-week) and late (6-month) CMR for clinical indication. LGE sequences were used to analyze the presence of LVTh. Baseline clinical characteristics were recorded. Echocardiography (Echo) was performed before discharge and left ventricular (LV) ejection fraction (LVEF, in %), LV end-diastolic and end-systolic diameters (in mm), tricuspid annular plane systolic excursion (TAPSE, in mm), E and A waves velocities (in m/s) and left auricular antero-posterior diameter (in mm) were measured. ECG during admission were analyzed and maximum and minimum ST-segment elevation, resolution of ST-segment (in %) and the number of leads with Q wave and ST-segment elevation &amp;gt;1mm (Q-STE) were recorded. Univariate and multivariate comparisons were performed to check for an association with LVTh in the first 6 months after STEMI (by CMR). A p&amp;lt;0.05 was considered statistically significant. Results The final cohort comprised 377 STEMI patients (mean age 58.51±11.64 years, 82% male). LVTh was detected in 29 (7.7%) patients by CMR during the first 6 months after STEMI. Predictors of LVTh on multivariate analysis were anterior infarction (HR 4.57 [1.28-16.29], p=0.02), Echo-LVEF (HR 0.97 [0.93-0.99] per %, p=0.04) and Q-STE (HR 1.33 [1.06-1.67] per lead, p=0.01). Echo-LVEF (best cut-off: ≤48%) and Q-STE (best cut-off: &amp;gt;3 leads) were dichotomized and several risk categories for LVTh were defined. In patients with zero or one risk factor the prevalence of LVTh ranged from 1.6% to 5.2% (if anterior infarction and no other risk factors). Patients with anterior infarction and any other risk factor had a 14.3% prevalence of LVTh. However, the highest prevalence was found in patients with concomitantly anterior infarction, Echo-LVEF ≤48% and Q-STE in &amp;gt;3 leads - in this subgroup (n=34, 9% of the cohort) LVTh was found in 26.5% of patients. Conclusions Left ventricular thrombus occurrence in the first 6 months after STEMI can be predicted by readily available clinical (anterior infarction), echocardiographic (LVEF) and ECG (Q-STE) variables before discharge. More than a quarter of patients with anterior infarction, Echo-LVEF≤48% and Q-STE in &amp;gt;3 leads depict LVTh. This could help select patients who should undergo CMR after infarction for LVTh detection.Central Figure.

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&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. 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 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 &amp;lt; 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 &lt;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&lt;0.001) and higher in men vs women (p&lt;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&lt;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&lt;0.001 and r=-0.51, p&lt;0.001 respectively). LVMi had a very strong inverse correlation with LATEF (r=-0.74, p&lt;&lt;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. &lt;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.