Cardiac Magnetic Resonance T1 Research Articles

Reference values of myocardial native T1 and extracellular volume in patients without structural heart disease and had negative 3T cardiac magnetic resonance adenosine stress test.

To establish the reference values of native T1 and extracellular volume (ECV) in patients without structural heart disease and had a negative adenosine stress 3T cardiac magnetic resonance. Short-axis T1 mapping images were acquired using a modified Look-Locker inversion recovery technique before and after administration of 0.15mmol/kg gadobutrol to calculate both native T1 and ECV. To compare the agreement between measurement strategies, regions of interest (ROI) were drawn in all 16 segments then averaged to represent mean global native T1. Additionally, an ROI was drawn in the mid-ventricular septum on the same image to represent the mid-ventricular septal native T1. Fifty-one patients (mean 65years, 65% women) were included. Mean global native T1 averaged from all 16 segments and a mid-ventricular septal native T1 were not significantly different (1221.2±35.2 vs 1228.4±43.7ms, p=0.21). Men had lower mean global native T1 (1195±29.8 vs 1235.5±29.4ms, p<0.001) than women. Both mean global and mid-ventricular septal native T1 were not correlated with age (r=0.21, p=0.13 and r=0.18, p=0.19, respectively). The calculated ECV was 26.6±2.7%, which was not influenced by either gender or age. We report the first study to validate the native T1 and ECV reference ranges, factors influencing T1, and the validation across measurement methods in older Asian patients without structural heart disease and had a negative adenosine stress test. These references allow for better detection of abnormal myocardial tissue characteristics in clinical practice.

Left Ventricle Detection from Cardiac Magnetic Resonance Relaxometry Images Using Visual Transformer

Left Ventricle (LV) detection from Cardiac Magnetic Resonance (CMR) imaging is a fundamental step, preliminary to myocardium segmentation and characterization. This paper focuses on the application of a Visual Transformer (ViT), a novel neural network architecture, to automatically detect LV from CMR relaxometry sequences. We implemented an object detector based on the ViT model to identify LV from CMR multi-echo T2* sequences. We evaluated performances differentiated by slice location according to the American Heart Association model using 5-fold cross-validation and on an independent dataset of CMR T2*, T2, and T1 acquisitions. To the best of our knowledge, this is the first attempt to localize LV from relaxometry sequences and the first application of ViT for LV detection. We collected an Intersection over Union (IoU) index of 0.68 and a Correct Identification Rate (CIR) of blood pool centroid of 0.99, comparable with other state-of-the-art methods. IoU and CIR values were significantly lower in apical slices. No significant differences in performances were assessed on independent T2* dataset (IoU = 0.68, p = 0.405; CIR = 0.94, p = 0.066). Performances were significantly worse on the T2 and T1 independent datasets (T2: IoU = 0.62, CIR = 0.95; T1: IoU = 0.67, CIR = 0.98), but still encouraging considering the different types of acquisition. This study confirms the feasibility of the application of ViT architectures in LV detection and defines a benchmark for relaxometry imaging.

Myocardial oedema contributes to interstitial expansion and associates with mechanical and electrocardiographic changes in takotsubo syndrome: a CMR T1 and T2 mapping study.

myocardial oedema is largely represented in takotsubo syndrome (TTS) and may contribute to alter the myocardium morphology and function. The aim of the study is to describe relationships between oedema, mechanical, and electrical abnormalities in TTS. the study included n = 32 hospitalized TTS patients and n = 23 controls. Cardiac magnetic resonance (CMR) with tissue mapping and feature tracking was performed with concomitant 12-lead electrocardiogram (ECG) recording. Mean age of TTS was 72 ± 12 years old, 94% women. Compared with controls, patients had higher left ventricular (LV) mass, worse systolic function, higher septal native T1 (1116 ± 73 msec vs. 970 ± 23 msec, P < 0.001), T2 (56 ± 5 msec vs. 46 ± 2 msec, P < 0.001), and extracellular volume (ECV) fraction (32 ± 5% vs. 24 ± 1%, P < 0.001). TTS patients had higher apicobasal gradient of T2 values (12 ± 6 msec vs. 2 ± 6 msec, P < 0.001); basal LV wall displayed higher native T1, T2, and ECV (all P < 0.002) but similar circumferential strain against controls (-23 ± 3% vs. -24 ± 4%, P = 0.351). In the TTS cohort, septal T2 values showed significant correlations with native T1 (r = 0.609, P < 0.001), ECV (r = 0.689, P < 0.001), left ventricular ejection fraction (r = -0.459, P = 0.008) and aVR voltage (r = -0.478, P = 0.009). Negative T-wave voltage and QTc length correlated with apicobasal T2 mapping gradient (r = 0.499, P = 0.007 and r = 0.372, P = 0.047, respectively) but not with other tissue mapping measurements. CMR T1 and T2 mapping demonstrated increased myocardial water content conditioning interstitial expansion in acute TTS, detected even outside areas of abnormal wall motion. Oedema burden and distribution associated with mechanical and electrocardiographic changes, making it a potential prognostic marker and therapeutic target in TTS.

Cardiac Magnetic Resonance Imaging T1 and T2 Mapping in Systemic Lupus Erythematosus in Relation to Antimalarial Treatment.

Patients with systemic lupus erythematosus (SLE) are at risk of cardiac disease including antimalarial-induced cardiomyopathy (AMIC). The purpose of this study is to evaluate cardiac magnetic resonance imaging parametric mapping findings in SLE patients with AMIC and investigate the relationship of T1/T2 mapping to antimalarial (AM) treatment duration. All patients with SLE who had undergone cardiac magnetic resonance imaging with T1/T2 mapping for evaluation of suspected cardiac disease between 2018 and 2021 were evaluated and compared with healthy controls. To facilitate comparison between scanners, T1/T2 values were converted to a z -score using scanner-specific local reference values. Patients were classified into 3 groups: AMIC, myocarditis, and other (no AMIC or myocarditis). Forty-five SLE patients (47±17y, 80% female; 8 [18%] with AMIC and 7 [16%] with myocarditis) and 30 healthy controls (39±15y, 60% female) were included. Patients with AMIC had higher T1 and T2 compared with controls ( z -score 1.1±1.3 vs. 0±0.6, P =0.01 and 1.7±1.1 vs. 0±1.0, P <0.01, respectively) and lower values compared with those with myocarditis (3.7±1.6, P <0.01 and 4.0±2.0, P <0.01, respectively). T1 correlated negatively with AM treatment duration in patients without AMIC or myocarditis ( r =-0.36, P =0.048) and positively in patients with AMIC ( r =0.92, P =0.001). AM treatment duration did not correlate significantly with T1 in patients with myocarditis or with T2 in any group. The relationship between T1 and AM treatment duration differed between groups. Native T1 decreases with longer treatment in patients without AMIC or myocarditis, possibility due to glycosphingolipid accumulation. In patients with AMIC, increasing T1 with longer treatment could reflect fibrosis.

Comprehensive cardiac magnetic resonance T1, T2, and extracellular volume mapping to define Duchenne cardiomyopathy

BackgroundCardiomyopathy is the leading cause of death in Duchenne muscular dystrophy (DMD). Cardiac magnetic resonance (CMR) parametric mapping sequences offer insights into disease pathophysiology. We propose a novel approach by leveraging T2 mapping in conjunction with T1 and extracellular volume (ECV) mapping to perform a virtual myocardial biopsy. While previous work has attempted to describe myocardial changes in DMD, our inclusion of T2 mapping enables comprehensive categorization of myocardial tissue characteristics of fibrosis, edema, and fat to better understand the pathological composition of the myocardium with disease progression. MethodsDMD patients (n = 49; median: 12 years-old) underwent CMR, including T1, T2, and ECV. Categories were defined as normal, isolated high T1 (normal ECV, high T1, normal T2), fibrosis (high ECV, normal or high T1, normal T2), edema (normal or high ECV, normal or high T1, high T2), fat (normal ECV, low T1, high T2) or fibrofatty (high ECV, low T1, high T2). ResultsMedian left ventricular ejection fraction (LVEF) was 59% with 27% having LVEF < 55%. Those with normal LVEF and no late gadolinium enhancement (37%) were younger in age (10.5 ± 2.6 vs. 15.0 ± 4.3 years-old, p < 0.001). Native T1 was elevated in at least one slice in 82% of patients. Those with high T2 at any slice (27%) were older (p = 0.005) and had lower LVEF (p = 0.005) compared with subjects with normal T2 (73%). The most common myocardial characterization was fibrosis (43%) followed by isolated high T1 (24%). Of the 13 with high T2, ten were categorized as edema, two as fibrofatty, and one as fat. ConclusionCMR parametric mapping sequences offer insights into Duchenne cardiomyopathy pathophysiology, which should drive development of therapeutic interventions aimed at these targets. Myocardial fibrosis is common in DMD. Patients with elevated T2 were older and had lower LVEF. Though fat infiltration was present, the majority of subjects with elevated T2 met criteria for myocardial edema.

PS-C05-3: ESTIMATION OF PULMONARY PULSATILE ARTERIAL LOAD IN PATIENTS UNDERGOING INVESTIGATION FOR PULMONARY HYPERTENSION

Objective: Diagnosis of pulmonary hypertension (PH) is typically confirmed by elevation of the pulmonary artery (PA) pressure and/or pulmonary vascular resistance (PVR). However, PVR may overlook the pulsatile component of RV hydraulic work which involves the dynamic interplay between PA resistance and compliance. PA vascular impedance (PVZ) offers a more comprehensive assessment of RV and PA load. This study aims to apply a method of PA pulsatile load as PVZ determination in a cohort of patients referred for PH evaluation. Design and Methods: Fifty-eight participants (71% females, mean 53 ± 18 years) were recruited, and underwent right heart catheterisation (RHC) to measure systolic (sPAP), diastolic (dPAP), mean (mPAP), and PA wedge pressures (PAWP), cardiac output (CO) and PVR; classified as precapillary PH (PrecPH), isolated postcapillary PH (IpcPH), combined PH (CpcPH) and control group. PA flows were recorded using 3T cardiac magnetic resonance (CMR); RV volume (V) were obtained by contouring endocardial and epicardial borders on the short axis at end diastolic (ED) and end systolic (ES) phases, and ejection fraction (RVEF) was calculated as (RVEDV - RVESV)/RVEDVx100. Volumetric flow was measured using phase-contrast velocity quantification using 3T cardiac magnetic resonance (CMR). PVZ was expressed as the relationship of pulsatile pressure to pulsatile flow in the frequency domain. Results: 76% of patients had evidence of PH on RHC (8 PrecPH, 17 IpcPH, 9 CpcPH). CpcPH and PrecPH patients tended to show poorer RV contractility compared with control and IpcPH groups, albeit not statistically significant. PVZ was highest in patients with PrecPH and CpcPH, while lowest in those with IpcPH. A correlation analysis was performed to seek association between mPAP, PVR and PVZ and other variables thought to be related to PH. In PrecPH, increased mPAP was found to be associated with raised PVR (p &lt; 0.001; R = 0.94) and PVZ (p &lt; 0.001; R = 0.78). However, there was no association between elevated mPAP and PVZ in IpcPH and CpcPH, despite a significant correlation with PVR (IpcPH P = 0.03, R = 0.55; CpcPH P = 0.01, R = 0.77). Conclusion: We describe a straightforward method to measure and compare pulsatile vascular load of the systemic and pulmonary circulations simultaneously, allowing further quantification of systemic/pulmonary vascular interactions. Further research is required to evaluate small-vessel contributions to the arterial circulation, especially in the pulmonary system.

S-37-4: TRANSCATHETER AORTIC VALVE REPLACEMENT DOES NOT RESULT IN SUSTAINED LOAD TRANSFER WITH INCREASED VASCULAR LOAD

Objectives: Transcatheter aortic valve replacement (TAVR) is an effective treatment for aortic stenosis (AS) by reducing the load placed on the left ventricle (LV) by the stenotic valve. Although systolic pressure is reported to increase in 50% of individuals after TAVR, its effects on steady and pulsatile vascular load represented by the systemic vascular resistance (SVR) and impedance of the proximal ascending aorta (Zc) respectively is less well understood. Using a previously validated non-invasive load estimation technique, we investigated the valvulo-arterial interaction in AS patients pre- and post-TAVR. Design and Method: In AS patients being assessed for TAVR, the proximal thoracic aorta flows, LV volume and function were recorded using 3T cardiac magnetic resonance (CMR) using phase-contrast velocity quantification. Simultaneous radial tonometric pressure was acquired during CMR and brachial cuff pressure was recorded. Aortic pressure was derived offline using SphygmoCor 8.1 (AtCor Medical, Sydney) from radial pressure, and calibrated to brachial pressure. Flow was acquired at 5 cm above the aortic valve at the level of the pulmonary artery bifurcation to avoid flow artefact from the TAVR prosthesis. Baseline and follow-up measurements were made before and after treatment with TAVR. Values pre- and post-TAVR were compared, and indices of pulsatile arterial load were calculated using frequency domain analysis. Results: A total of 17 patients (mean age 80 ± 6 years, 7 females) were recruited, with a median follow up of 54.5 days post-TAVR. In the post-TAVR measurements, a significant improvement in aortic peak volumetric flow (336 ± 79 ml/s vs 389 ± 110 ml, P = 0.011) was observed with an associated reduction in peak aortic velocity (189 ± 65 cm/s vs 126 ± 24 cm/s, P = 0.002). However, there was no statistical difference in heart rate (70 ± 9 beats per minute vs 68 ± 12 beats per minute), mean central aortic pressure (98 ± 13mmHg vs 99 ± 11mmHg), or the steady vascular load parameters of SVR (1860 ± 513 dynes.s/cm5 vs 1999 ± 561 dynes. s/cm5, P = 0.284) and pulsatile load Zc of the aorta (119 ± 51 dynes.s/cm5 vs 106 ± 43 dynes.s/cm5, P = 0.102). Conclusion: TAVR relieves valvular obstruction but does not result in significant alterations of vascular load in the short to medium term. The previously reported acute load transfer immediately following TAVR appears to resolve with time. Further study examining the effect of TAVR on external LV work may help to elucidate the energy consumption by the vascular system after correction of valvular obstruction from AS.

PS-C05-2: COMPARISON OF NON-INVASIVE VASCULAR LOAD ESTIMATION OF THE SYSTEMIC AND PULMONARY ARTERIAL CIRCULATION IN PATIENTS UNDERGOING INVESTIGATION FOR PULMONARY HYPERTENSION

Objective: Quantification of characteristic impedance (Zc) as an estimate of pulsatile load is now feasible using a hybrid non-invasive and invasive technique in any specific vascular bed. Vascular resistance (mean pressure ÷ mean flow) in a system may ignore the pulsatile component of ventricular hydraulic work incorporating the dynamic interaction between vascular resistance, compliance and wave reflection. This interaction is represented by vascular impedance which offers a comprehensive assessment of hydraulic load. This study aims to compare systemic (Ao-Zc) and pulmonary (PA-Zc) Zc in a cohort of patients with suspected pulmonary hypertension (PH) referred for routine right heart catheterisation (RHC) followed by cardiac magnetic resonance (CMR). Design and Methods: Thirty participants (77% females, mean 56 ± 18 years) were recruited, and had routine right heart catheterisation (RHC) to measure systolic (sPAP), diastolic (dPAP), mean (mPAP), and PA wedge pressures (PAWP), cardiac output (CO) and PVR. The remaining patients were assigned to the control group. Ao pressures were calibrated to brachial cuff pressures and derived from radial tonometric pressure acquisition (systolic, AoSP; diastolic, AoDP; mean, MP) before/ after CMR. Ao and PA volumetric flows were recorded using 3T cardiac magnetic resonance (CMR) using phase-contrast velocity quantification. Zc was expressed as the relationship of PA pulsatile pressure to PA pulsatile flow in the frequency domain. Results: 80% of patients had evidence of PH on RHC and classified as pre-capillary PH (n = 11, PrecPH), isolated post-capillary PH (n = 8, IpcPH) and combined PH (n = 5, CpcPH). In patients without PH, Ao-Zc was 83.0 ± 38.4 dynes.s.cm-5 and PA-Zc was 48.8 ± 13.7 dynes.s.cm-5, with PA-Zc being 33% lower than those with PH (72.9 ± 28.0 dynes.s.cm-5, p = 0.005) and Ao-Zc non-significantly lower (77.3 ± 29.6 dynes.s.cm-5, p = 0.575). In patients with PH, different hemodynamic relationships were observed. In those with PrecPH, PA-Zc was 9% higher than Ao-Zc (p = 0.74). An inverse relationship between PA-Zc and Ao-Zc was found in those with IpcPH (p = 0.11). This relationship approached 1:1 (p = 0.27) in patients with CpcPH. PA-Zc spectra in CpcPH subjects were qualitatively similar to Ao-Zc spectra, although the ratio of PVR to Zc was smaller. Conclusion: We describe a straightforward method to measure and compare pulsatile vascular load of the systemic and pulmonary circulations simultaneously, allowing further quantification of systemic/pulmonary vascular interactions. Further research is required to evaluate small-vessel contributions to the arterial circulation, especially in the pulmonary system.

The Effects of Vitamin D on Myocardial Function Demonstrated by Speckle-Tracking Echocardiography in Children with Beta Thalassemia.

Beta thalassemia major is an inherited hemoglobin disorder resulting in chronic hemolytic anemia. Cardiac involvement is the main cause of death in patients. Speckle-tracking echocardiography is a feasible method for the evaluation of cardiac function via an assessment of the longitudinal deformation of the myocardium through the cardiac cycle. The aim of our study is to evaluate the association between vitamin D deficiency and deformation of the left ventricular myocardium measured by speckle-tracking echocardiography in children with thalassemia major. In this prospective study, 33 thalassemic patients with vitamin D deficiency were enrolled. Cardiac magnetic resonance T2* value, conventional echocardiography, and speckle tracking, and also left ventricular longitudinal and circumferential strain values were measured. Myocardial functions of the patients with vitamin D deficiency or insufficiency were evaluated by speckle-tracking echocardiography before and after vitamin D replacement. The mean age of the patients was 15.4 ± 3.09 years. Vitamin D level was deficient in 30 (90%) and insufficient in 3 (10%) of them. Speckle-tracking analysis showed a significantly decreased absolute value of the left ventricular global longitudinal strain before vitamin D replacement. A significant improvement in the global longitudinal strain was detected after vitamin D replacement (P < 0.05). A statistically significant increase was observed in parameters showing left ventricular systolic and diastolic functions after vitamin D replacement. Vitamin D deficiency is frequently observed and causes decreased contractility in thalassemic patients. In our study, we observed that our patients' cardiac functions had improved after vitamin D replacement therapy.

Left Ventricular Adverse Remodeling in Ischemic Heart Disease: Emerging Cardiac Magnetic Resonance Imaging Biomarkers

Post-ischemic left ventricular (LV) remodeling is a biologically complex process involving myocardial structure, LV shape, and function, beginning early after myocardial infarction (MI) and lasting until 1 year. Adverse remodeling is a post-MI maladaptive process that has been associated with long-term poor clinical outcomes. Cardiac Magnetic Resonance (CMR) is the best tool to define adverse remodeling because of its ability to accurately measure LV end-diastolic and end-systolic volumes and their variation over time and to characterize the underlying myocardial changes. Therefore, CMR is the gold standard method to assess in vivo myocardial infarction extension and to detect the presence of microvascular obstruction and intramyocardial hemorrhage, both associated with adverse remodeling. In recent times, new CMR quantitative biomarkers emerged as predictive of post-ischemic adverse remodeling, such as T1 mapping, myocardial strain, and 4D flow. Additionally, CMR T1 mapping imaging may depict infarcted tissue and assess diffuse myocardial fibrosis by using surrogate markers such as extracellular volume fraction, which may predict functional recovery or risk stratification of remodeling. Finally, there is emerging evidence supporting the utility of intracavitary blood flow kinetic energy and hemodynamic features assessed by the 4D flow CMR technique as early predictors of remodeling.

Cardiac magnetic resonance T2* mapping in patients with COVID-19 pneumonia is associated with serum ferritin level?

The coronavirus disease of 2019 (COVID-19)-related myocardial injury is an increasingly recognized complication and cardiac magnetic resonance imaging (MRI) has become the most commonly used non-invasive imaging technique for myocardial involvement. This study aims to assess myocardial structure by T2*-mapping which is a non-invasive gold-standard imaging tool for the assessment of cardiac iron deposition in patients with COVID-19 pneumonia without significant cardiac symptoms. Twenty-five patients with COVID-19 pneumonia and 20 healthy subjects were prospectively enrolled.Cardiac volume and function parameters, myocardial native-T1, and T2*-mapping were measured. The association of serum ferritin level and myocardial mapping was analyzed. There was no difference in terms of cardiac volume and function parameters. The T2*-mapping values were lower in patients with COVID-19 compared to controls (35.37 [IQR 31.67-41.20] ms vs. 43.98 [IQR 41.97-46.88] ms; p < 0.0001), while no significant difference was found in terms of native-T1 mapping value(p = 0.701). There was a positive correlation with T2*mapping and native-T1 mapping values (r = 0.522, p = 0.007) and negative correlation with serum ferritin values (r = -0.653, p = 0.000), while no correlation between cardiac native-T1 mapping and serum ferritin level. Negative correlation between serum ferritin level and T2*-mapping values in COVID-19 patients may provide a non-contrast-enhanced alternative to assess tissue structural changes in patients with COVID-19. T2*-mapping may provide a non-contrast-enhanced alternative to assess tissue alterations in patients with COVID-19. Adding T2*-mapping cardiac MRI in patients with myocardial pathologies would improve the revealing of underlying mechanisms. Further in vivo and ex vivo animal or human studies designed with larger patient cohorts should be planned.

Effect of ticagrelor and prasugrel on remote myocardial inflammation in patients with acute myocardial infarction with ST-elevation: a CMR T1 and T2 mapping study.

Acute myocardial ischaemia triggers a non-specific inflammatory response of remote myocardium through the increase of plasma concentrations of acute-phase proteins, which causes myocardial oedema. As ticagrelor has been shown to significantly decrease circulating levels of several pro-inflammatory cytokines in patients after acute myocardial infarction with ST-elevation (STEMI), we sought to investigate a potential suppressive effect of ticagrelor over prasugrel on cardiac magnetic resonance (CMR) T1 and T2 values in remote myocardium. Ninety STEMI patients were prospectively included and randomised to receive either ticagrelor or prasugrel maintenance treatment after successful primary percutaneous coronary intervention. Patients underwent CMR after 2-7 days. The protocol included long and short axis cine imaging, T1 mapping, T2 mapping and late gadolinium enhancement imaging. After excluding 30 patients due to either missing images or insufficient quality of the T1 or T2 maps, 60 patients were included in our analysis. Of those, 29 patients were randomised to the ticagrelor group and 31 patients to the prasugrel group. In the remote myocardium, T1 values did not differ between groups (931.3 [919.4-950.4] ms for ticagrelor vs. 932.6 [915.5-949.2] ms for prasugrel (p = 0.94)), nor did the T2 values (53.8 ± 4.6 ms for ticagrelor vs. 53.7 ± 4.7 ms for prasugrel (p = 0.86)). Also, in the infarcted myocardium, T1 and T2 values did not differ between groups. In revascularised STEMI patients, ticagrelor maintenance therapy did not show superiority over prasugrel in preventing early remote myocardial inflammation as assessed by CMR T1 and T2 mapping.

Interpretation of pre-morbid cardiac 3T MRI findings in overweight and hypertensive young adults.

In young adults, overweight and hypertension possibly already trigger cardiac remodeling as seen in mature adults, potentially overlapping non-ischemic cardiomyopathy findings. To this end, in young overweight and hypertensive adults, we aimed to investigate changes in left ventricular mass (LVM) and cardiac volumes, and the impact of different body scales for indexation. We also aimed to explore the presence of myocardial fibrosis, fat and edema, and changes in cellular mass with extracellular volume (ECV), T1 and T2 tissue characteristics. We prospectively recruited 126 asymptomatic subjects (51% male) aged 27-41 years for 3T cardiac magnetic resonance imaging: 40 controls, 40 overweight, 17 hypertensive and 29 hypertensive overweight. Myocyte mass was calculated as (100%-ECV) * height2.7-indexed LVM. Absolute LVM was significantly increased in overweight, hypertensive and hypertensive overweight groups (104 ± 23, 109 ± 27, 112 ± 26 g) versus controls (87 ± 21 g), with similar volumes. Body surface area (BSA) indexation resulted in LVM normalization in overweights (48 ± 8 g/m2) versus controls (47 ± 9 g/m2), but not in hypertensives (55 ± 9 g/m2) and hypertensive overweights (52 ± 9 g/m2). BSA-indexation overly decreased volumes in overweight versus normal-weight (LV end-diastolic volume; 80 ± 14 versus 92 ± 13 ml/m2), where height2.7-indexation did not. All risk groups had lower ECV (23 ± 2%, 23 ± 2%, 23 ± 3%) than controls (25 ± 2%) (P = 0.006, P = 0.113, P = 0.039), indicating increased myocyte mass (16.9 ± 2.7, 16.5 ± 2.3, 18.1 ± 3.5 versus 14.0 ± 2.9 g/m2.7). Native T1 values were similar. Lower T2 values in the hypertensive overweight group related to heart rate. In conclusion, BSA-indexation masks hypertrophy and causes volume overcorrection in overweight subjects compared to controls, height2.7-indexation therefore seems advisable.

Abstract 9934: Albuminuria Entails Myocardial Fibrosis at the Population Level: The MESA STUDY

Introduction: Microalbuminuria(MA) is an established predictor of CVD. Experimental and small observational studies have shown an association between MA and myocardial fibrosis(MF) among patients with type two diabetes mellitus (DM). However, the relationship to MF in a community-based population is unknown. Hypothesis: We hypothesize that participants with MA will have higher rates of MF measured by cardiac magnetic resonance T1(CMR-T1) mapping. Methods: A total of 1,010 men (mean age:68±9) and 1,003 women (mean age: 70 ± 9) who had both urine albumin and creatinine measurements and CMR-T1 for evaluation of MF were included in MESA visit 5. To study the association of MA among various populations, analyses were then stratified by diabetes stage and by sex. Multivariable linear regression models were constructed to assess the associations of MA with ECV and native T1 time. Results: Higher levels of MA were independently associated with greater evidence of MF (Fig.A). Participants with worse severity of MF (defined as ECV &gt;30%), that were men, or had either history of pre-DM or DM had significantly higher levels of MA, whereas no difference in MA levels were found in women (Fig.B). Among men only, each 1-SD increment greater MA levels was significantly associated with 0.3% higher ECV and 2.6% higher native T1. Among participants with pre-diabetes and diabetes, each 1-SD increment in MA levels was associated with 0.4% and 0.3% higher ECV and 3% and 3.5% higher native T1, respectively (Fig.A) Conclusions: In a community-based setting, measurable MA, independent of age, sex, DM, history of CVD, and other clinical variables, was related to subclinical MF. This association was more significant among participants with preDM, Type2DM, and men. These findings demonstrate that MA, a urine biomarker, may identify participants with high subclinical profibrotic condition. Further studies are warranted to address whether treatment of MA will be associated with lower MF.

Abstract 12034: Diffuse Myocardial Fibrosis, Its Distribution And Relationship To Clinical Outcome And Ventricular Function In Single Ventricles Before And After Fontan: A Cardiac Magnetic Resonance Outcome Study

Introduction: Patients with single ventricle (SV) anatomy are susceptible to myocardial fibrosis as measured by cardiac magnetic resonance (CMR) imaging. This study investigated the association of diffuse myocardial fibrosis prior to Fontan with ventricular function and clinical outcomes after Fontan completion. Methods: Retrospective cohort study of consecutive SV patients who underwent CMR T1 mapping prior to Fontan. Native T1 time and extracellular volume (ECV) of the dominant ventricle and a free wall region of interest (ROI) were measured on CMR pre-Fontan. Longitudinal strain was measured on echocardiography pre- and post-Fontan. Associations between pre-Fontan fibrosis, strain, and clinical outcomes were evaluated using linear and logistic regression. Results: 40 patients were included (table 1). ECV directly correlated to the number of ICU days and post-Fontan strain. The coefficient of variation (CV) of ECV directly correlated to hospital and chest tube days. When limited to single right ventricles (RV), T1 directly correlated to strain pre-Fontan. ECV directly correlated to ICU days as well as strain pre- and post-Fontan. ECV ROI directly correlated to strain post-Fontan. The CV of ECV directly correlated to the number of hospital days (table 2). Conclusions: Myocardial fibrosis prior to Fontan may portend the clinical course after Fontan and should be considered for risk stratification. The CV of ECV is a novel measure of diffuse fibrosis that is associated with clinical outcome. For single RV patients, fibrosis before Fontan is associated with worse ventricular function after. The use of reverse remodeling agents prior to Fontan should be considered.

Non-contrast cardiac magnetic resonance imaging after SARS-CoV2 infection or vaccination in asymptomatic adolescents: insights from the EnIGMA study

Abstract Background Myocarditis after SARS-CoV2 infection or vaccination is rare, but seems to be relatively more frequent in young population. Cardiac magnetic resonance (CMR) T2 weighted sequences have the potential to detect subclinical myocarditis. However, there is paucity of data on the potential myocardial involvement after SARS-CoV2 infection or vaccination in asymptomatic adolescents. Purpose To evaluate the presence of subclinical myocardial damage in adolescents who were infected with SARS-CoV2 or vaccinated against SARS-CoV2 using non-contrast CMR imaging. Methods Asymptomatic adolescents enrolled in the “Early ImaginG Markers of unhealthy lifestyles in Adolescents” (EnIGMA) project were scanned using a 3-Tesla CMR scanner between March 2021 and October 2021. CMR scans included CINE imaging and myocardial T2-mapping sequences. SARS-CoV2 IgG antibody testing was performed in capillary blood samples, and date of confirmed SARS-CoV2 infection and/or vaccination if any was collected. Participants were assigned to three different groups according to SARS-CoV2 status: Group 1 (non-infected and non-vaccinated), Group 2 (infected and non-vaccinated), and Group 3 (vaccinated, independently of past infection status). CMR images were analyzed by experienced observers blinded to adolescent's SARS-CoV2 status. ANOVA and multiple regression analysis, together with correlation coefficients, were used to study between-group differences and associations among variables of interest. Results A total of 115 adolescents with a mean age of 16.0 years (standard deviation (SD)=0.4), 54% girls, completed the CMR study and SARS-CoV2 data successfully, and were assigned to Group 1 (n=72), Group 2 (n=22), and Group 3 (n=21). Left and right ventricular ejection fraction (LVEF/RVEF) did not significantly differ among groups: mean LVEF was 62.8% (SD=4.1), 63.0% (SD=3.7) and 60.9% (SD=3.9) [p=0.12] and mean RVEF was 56.5% (SD=4.2), 56.5% (SD=5.5) and 54.5% (SD=5.1) [p=0.23] in Groups 1, 2 and 3, respectively. Similarly, there were no between-group significant differences in myocardial T2 relaxation values: mean T2 values were 44.1 ms (SD=2.2), 44.1 ms (SD=1.8) and 44.4 ms (SD=1.9) in Groups 1, 2, and 3, respectively (p=0.63) (Figure 1). No differences were found either after adjusting for age and gender. Median time (interquartile range) from date of infection or vaccination to CMR acquisition was 133 (121) days and 28 (38) days in Group 2 and Group 3, respectively. No correlation between time from infection/vaccination to CMR acquisition and T2 values was detected (Figure 2). Conclusions This observational study did not find evidence of subclinical myocardial involvement after SARS-CoV2 infection or vaccination in asymptomatic adolescents, as assessed with T2-mapping magnetic resonance imaging. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Instituto de Salud Carlos III (ISCIII)-Fondo de Investigaciόn Sanitaria.European Regional Development Fund/European Social Fund (“A way to make Europe”/“Investing in your future”.

Myocardial edema during chemotherapy for gynecologic malignancies: A cardiac magnetic resonance T2 mapping study.

ObjectiveMyocardial edema is an early manifestation of chemotherapy-related myocardial injury. In this study, we used cardiac magnetic resonance (CMR) T2 mapping to assess myocardial edema and its changes during chemotherapy for gynecologic malignancies.MethodsWe enrolled 73 patients receiving chemotherapy for gynecologic malignancies, whose the latest cycle was within one month before the beginning of this study, and 41 healthy volunteers. All participants underwent CMR imaging. Of the 73 patients, 35 completed CMR follow-up after a median interval of 6 (3.3 to 9.6) months. The CMR sequences included cardiac cine, T2 mapping, and late gadolinium enhancement.ResultsMyocardial T2 was elevated in patients who were treated with chemotherapy compared with healthy volunteers [41ms (40ms to 43ms) vs. 41ms (39ms to 41ms), P = 0.030]. During follow-up, myocardial T2 rose further [40ms (39ms to 42ms) vs. 42.70 ± 2.92ms, P < 0.001]. Multivariate analysis showed that the number of chemotherapy cycles was associated with myocardial T2 elevation (β = 0.204, P = 0.029). After adjustment for other confounders, myocardial T2 elevation was independently associated with a decrease in left ventricular mass (β = −0.186; P = 0.024).ConclusionIn patients with gynecologic malignancies, myocardial edema developed with chemotherapy cycles increase, and was associated with left ventricular mass decrease. T2 mapping allows the assessment of myocardial edema and monitoring of its change during chemotherapy.

Association of heart failure and liver T1 mapping in cardiac magnetic resonance imaging

Abstract Background Heart failure culminates in liver congestion. As the liver can be assessed by cardiac magnetic resonance T1 mapping sequences, it represents a promising imaging biomarker for heart failure. Objectives To evaluate the association between heart failure and magnetic resonance liver T1 mapping, as a non-invasive imaging surrogate of liver congestion. Methods Patients with cardiac magnetic resonance including T1 mapping sequences on a single 1.5T scanner were consecutively included between 01/2017 and 12/2019. Liver T1 was measured in the left lobe, right lobe and caudate lobe on short axis view and in the liver dome on four chamber view. Echocardiographic and laboratory parameters were analyzed within 90 days of the cardiac magnetic resonance exam. Left ventricular filling pressures were assessed according to the European Association of Cardiovascular Imaging guidelines [1]. Liver T1 and echocardiographic parameters were compared between patients with and without elevated NT-proBNP levels (&amp;gt;125 pg/ml) using a Mann-Whitney U test. A multivariate logistic regression model was used to correct for age, sex, body mass index, left ventricular ejection fraction and the presence of atrial fibrillation. Results A total of 397 patients were included (median age 56, 127 females), of whom 138 patients (35%) presented with elevated NT-proBNP levels. Patients with elevated NT-proBNP levels had a larger indexed end-diastolic left ventricular volume (92 vs. 81 ml/m2, p&amp;lt;0.001), lower left ventricular ejection fraction (60 vs. 50%, p&amp;lt;0.001) and a higher E/E' ratio (11 vs. 8, p&amp;lt;0.001). Liver T1 was higher in patients with elevated NT-proBNP in the right liver lobe (670 vs. 596 ms, p&amp;lt;0.001) and the caudate lobe (664 vs. 598 ms, p&amp;lt;0.001), but not in the left liver lobe (571 vs. 568 ms, p=0.068) and in the liver dome (590 vs. 560 ms, p=0.1). Echocardiographic evaluation showed similar results with significant difference in T1 times between patients with elevated and non-elevated left ventricular filling pressures in caudate and right liver lobe. Liver T1 retained its predictive value when corrected for age, left ventricular ejection fraction and the presence of atrial fibrillation, when measured in the caudate lobe (adjusted odds ratio 1.013, 95% confidence interval 1.004–1.023, p=0.005) and in the right lobe (adjusted odds ratio 1.012, 95% confidence interval 1.003–1.021, p=0.009). Conclusions Elevated liver T1 in cardiac magnetic resonance imaging is associated with heart failure and represents an independent non-invasive imaging surrogate for liver congestion. Funding Acknowledgement Type of funding sources: None.

Extracellular Volume Fraction Based on Cardiac Magnetic Resonance T1 Mapping: An Effective Way to Evaluate Cardiac Injury Caused by Cardiac Amyloidosis in Patients with Multiple Myeloma.

Multiple myeloma (MM) is a hematological malignancy of plasma cell origin. Cardiac amyloidosis (CA) is a common form of heart damage caused by MM and is associated with a poor prognosis. This study was a prospective cohort study and was aimed at evaluating the clinical predictive value of extracellular volume fraction (ECV) based on cardiovascular magnetic resonance (CMR) T1 mapping for cardiac amyloidosis and cardiac dysfunction in MM patients. Fifty-one newly diagnosed MM patients in Zhongnan Hospital of Wuhan University were enrolled in the study. A total of 19 patients (19/51; 37.25%) developed CA. The basal ECV of CA group was significantly higher than that of the non-CA group (p < 0.01). Multivariate logistic regression analysis showed that basal ECV (OR = 1.551, 95% CI 1.084-2.219, p < 0.05) and LDH1 level (OR = 1.150, 95% CI 1.010-1.310, p < 0.05) were two independent risk factors for CA. Further study demonstrated that basal ECV in the heart failure group was significantly higher than that of the nonheart failure group (p < 0.01). Notably, ROC curve showed that basal ECV had a good predictive value for CA and heart failure, with AUC of 0.911 and 0.893 (all p < 0.01), and the best cutoff values of 38.35 and 37.45, respectively. Taken together, basal ECV is a good predictor of CA and heart failure for MM patients.

Empagliflozin reduces diffuse myocardial fibrosis by extracellular volume mapping: A meta-analysis of clinical studies.

ObjectiveThe aim of the study was to evaluate the effect of empagliflozin on diffuse myocardial fibrosis by cardiac magnetic resonance (CMR) T1 mapping.Research methods and proceduresDatabases including PubMed, Cochrane library, Embase, and Sinomed for clinical studies of empagliflozin on myocardial fibrosis were searched. Two authors extracted the data and evaluated study quality independently. Weighted mean difference (WMD) and 95% confidence intervals (CI) were used for continuous variables. Review Manager 5.3 was used to performed the analysis.ResultsSix studies were included in this meta-analysis. One of the six studies was assessed as poor quality by the assessment of methodological quality; however, the remaining five studies were considered good. The WMD value of △extracellular volume (ECV) was merged by the fixed-effect model, and the pooled effect size was -1.48 (95% CI -1.76 to -1.21, P < 0.00001), which means in favor of empagliflozin. Heterogeneity analysis did not find any heterogeneity (chi2 = 0.39, P = 0.82, I 2 = 0%). In addition, empagliflozin had a tendency to reduce ECV compared to treatment before with no statistical significance (WMD = -0.29, 95% CI -1.26 to 0.67, P = 0.55; heterozygosity test, chi2 = 2.66, P = 0.45, I 2 = 0%). The WMD value of △native T1 was also merged by the fixed-effect model, but the pooled effect size showed neither statistical difference between empagliflozin and placebo treatment (WMD = -5.40, 95% CI -21.63 to 10.83, P = 0.51) nor heterogeneity (chi2 = 0.05, P = 0.83, I 2 = 0%).ConclusionsEmpagliflozin has cardiovascular benefits by reducing diffuse myocardial fibrosis. ECV could act as a non-invasive imaging tool to assess diffuse myocardial fibrosis and monitor disease progression.Systematic Review Registration https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=324804, identifier: CRD42022324804