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Left ventricular assist devices (LVADs) are gaining increasing importance as therapeutic strategy in advanced heart failure (HF), not only as bridge to recovery or to transplant but also as destination therapy. Even though long-term LVADs are considered a precious resource to expand the treatment options and improve clinical outcome of these patients, these are limited by peri-operative and post-operative complications, such as device-related infections, haemocompatibility-related events, device mis-positioning, and right ventricular failure. For this reason, a precise pre-operative, peri-operative, and post-operative evaluation of these patients is crucial for the selection of LVAD candidates and the management LVAD recipients. The use of different imaging modalities offers important information to complete the study of patients with LVADs in each phase of their assessment, with peculiar advantages/disadvantages, ideal application, and reference parameters for each modality. This clinical consensus statement sought to guide the use of multimodality imaging for the evaluation of patients with advanced HF undergoing LVAD implantation. [ABSTRACT FROM AUTHOR]

Background: Four‐dimensional‐flow cardiac MR (4DF‐MR) offers advantages in primary mitral regurgitation. The relationship between 4DF‐MR‐derived mitral regurgitant volume (MR‐Rvol) and the post‐operative left ventricular (LV) reverse remodeling has not yet been established. Purpose: To ascertain if the 4DF‐MR‐derived MR‐Rvol correlates with the LV reverse remodeling in primary mitral regurgitation. Study Type: Prospective, single‐center, two arm, interventional vs. nonintervention observational study. Population: Forty‐four patients (male N = 30; median age 68 [59–75]) with at least moderate primary mitral regurgitation; either awaiting mitral valve surgery (repair [MVr], replacement [MVR]) or undergoing "watchful waiting" (WW). Field Strength/Sequence: 5 T/Balanced steady‐state free precession (bSSFP) sequence/Phase contrast imaging/Multishot echo‐planar imaging pulse sequence (five shots). Assessment: Patients underwent transthoracic echocardiography (TTE), phase‐contrast MR (PMRI), 4DF‐MR and 6‐minute walk test (6MWT) at baseline, and a follow‐up PMRI and 6MWT at 6 months. MR‐Rvol was quantified by PMRI, 4DF‐MR, and TTE by one observer. The pre‐operative MR‐Rvol was correlated with the post‐operative decrease in the LV end‐diastolic volume index (LVEDVi). Statistical Tests: Included Student t‐test/Mann–Whitney test/Fisher's exact test, Bland–Altman plots, linear regression analysis and receiver operating characteristic curves. Statistical significance was defined as P < 0.05. Results: While Bland–Altman plots demonstrated similar bias between all the modalities, the limits of agreement were narrower between 4DF‐MR and PMRI (bias 15; limits of agreement −36 mL to 65 mL), than between 4DF‐MR and TTE (bias −8; limits of agreement −106 mL to 90 mL) and PMRI and TTE (bias −23; limits of agreement −105 mL to 59 mL). Linear regression analysis demonstrated a significant association between the MR‐Rvol and the post‐operative decrease in the LVEDVi, when the MR‐Rvol was quantified by PMRI and 4DF‐MR, but not by TTE (P = 0.73). 4DF‐MR demonstrated the best diagnostic performance for reduction in the post‐operative LVEDVi with the largest area under the curve (4DF‐MR 0.83; vs. PMRI 0.78; and TTE 0.51; P = 0.89). Data Conclusion: This study demonstrates the potential clinical utility of 4DF‐MR in the assessment of primary mitral regurgitation. Evidence Level: 2 Technical Efficacy: Stage 5 [ABSTRACT FROM AUTHOR]

Quantification of myocardial scar from late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) images can be facilitated by automated artificial intelligence (AI)-based analysis. However, AI models are susceptible to domain shifts in which the model performance is degraded when applied to data with different characteristics than the original training data. In this study, CycleGAN models were trained to translate local hospital data to the appearance of a public LGE CMR dataset. After domain adaptation, an AI scar quantification pipeline including myocardium segmentation, scar segmentation, and computation of scar burden, previously developed on the public dataset, was evaluated on an external test set including 44 patients clinically assessed for ischemic scar. The mean ± standard deviation Dice similarity coefficients between the manual and AI-predicted segmentations in all patients were similar to those previously reported: 0.76 ± 0.05 for myocardium and 0.75 ± 0.32 for scar, 0.41 ± 0.12 for scar in scans with pathological findings. Bland-Altman analysis showed a mean bias in scar burden percentage of -0.62% with limits of agreement from -8.4% to 7.17%. These results show the feasibility of deploying AI models, trained with public data, for LGE CMR quantification on local clinical data using unsupervised CycleGAN-based domain adaptation. Relevance statement: Our study demonstrated the possibility of using AI models trained from public databases to be applied to patient data acquired at a specific institution with different acquisition settings, without additional manual labor to obtain further training labels. [ABSTRACT FROM AUTHOR]

Background: Cardiac magnetic resonance (CMR) in the four-chamber plane offers comprehensive insight into the volumetrics of the heart. We aimed to develop an artificial intelligence (AI) model of time-resolved segmentation using the four-chamber cine. Methods: A fully automated deep learning algorithm was trained using retrospective multicentre and multivendor data of 814 subjects. Validation, reproducibility, and mortality prediction were evaluated on an independent cohort of 101 subjects. Results: The mean age of the validation cohort was 54 years, and 66 (65%) were males. Left and right heart parameters demonstrated strong correlations between automated and manual analysis, with a ρ of 0.91−0.98 and 0.89−0.98, respectively, with minimal bias. All AI four-chamber volumetrics in repeatability analysis demonstrated high correlation (ρ = 0.99−1.00) and no bias. Automated four-chamber analysis underestimated both left ventricular (LV) and right ventricular (RV) volumes compared to ground-truth short-axis cine analysis. Two correction factors for LV and RV four-chamber analysis were proposed based on systematic bias. After applying the correction factors, a strong correlation and minimal bias for LV volumetrics were observed. During a mean follow-up period of 6.75 years, 16 patients died. On stepwise multivariable analysis, left atrial ejection fraction demonstrated an independent association with death in both manual (hazard ratio (HR) = 0.96, p = 0.003) and AI analyses (HR = 0.96, p < 0.001). Conclusion: Fully automated four-chamber CMR is feasible, reproducible, and has the same real-world prognostic value as manual analysis. LV volumes by four-chamber segmentation were comparable to short-axis volumetric assessment. Trials registration: ClinicalTrials.gov: NCT05114785. Relevance statement: Integrating fully automated AI in CMR promises to revolutionise clinical cardiac assessment, offering efficient, accurate, and prognostically valuable insights for improved patient care and outcomes. Key points: • Four-chamber cine sequences remain one of the most informative acquisitions in CMR examination. • This deep learning-based, time-resolved, fully automated four-chamber volumetric, functional, and deformation analysis solution. • LV and RV were underestimated by four-chamber analysis compared to ground truth short-axis segmentation. • Correction bias for both LV and RV volumes by four-chamber segmentation, minimises the systematic bias. [ABSTRACT FROM AUTHOR]

Purpose: Exercise imaging using current modalities can be challenging. This was patient focused study to establish the feasibility and reproducibility of exercise-cardiovascular magnetic resonance imaging (EX-CMR) acquired during continuous in-scanner exercise in asymptomatic patients with primary mitral regurgitation (MR). Methods: This was a prospective, feasibility study. Biventricular volumes/function, aortic flow volume, MR volume (MR-Rvol) and regurgitant fraction (MR-RF) were assessed at rest and during low- (Low-EX) and moderate-intensity exercise (Mod-EX) in asymptomatic patients with primary MR. Results: Twenty-five patients completed EX-CMR without complications. Whilst there were no significant changes in the left ventricular (LV) volumes, there was a significant increase in the LVEF (rest 63 ± 5% vs. Mod-EX 68 ± 6%;p = 0.01). There was a significant reduction in the right ventricular (RV) end-systolic volume (rest 68 ml(60–75) vs. Mod-EX 46 ml(39–59);p < 0.001) and a significant increase in the RV ejection fraction (rest 55 ± 5% vs. Mod-EX 65 ± 8%;p < 0.001). Whilst overall, there were no significant group changes in the MR-Rvol and MR-RF, individual responses were variable, with MR-Rvol increasing by ≥ 15 ml in 4(16%) patients and decreasing by ≥ 15 ml in 9(36%) of patients. The intra- and inter-observer reproducibility of LV volumes and aortic flow measurements were excellent, including at Mod-EX. Conclusion: EX-CMR is feasible and reproducible in patients with primary MR. During exercise, there is an increase in the LV and RV ejection fraction, reduction in the RV end-systolic volume and a variable response of MR-Rvol and MR-RF. Understanding the individual variability in MR-Rvol and MR-RF during physiological exercise may be clinically important. [ABSTRACT FROM AUTHOR]

Background: Pulmonary transit time (PTT) can be measured automatically from arterial input function (AIF) images of dual sequence first-pass perfusion imaging. PTT has been validated against invasive cardiac catheterisation correlating with both cardiac output and left ventricular filling pressure (both important prognostic markers in heart failure). We hypothesized that prolonged PTT is associated with clinical outcomes in patients with heart failure. Methods: We recruited outpatients with a recent diagnosis of non-ischaemic heart failure with left ventricular ejection fraction (LVEF) < 50% on referral echocardiogram. Patients were followed up by a review of medical records for major adverse cardiovascular events (MACE) defined as all-cause mortality, heart failure hospitalization, ventricular arrhythmia, stroke or myocardial infarction. PTT was measured automatically from low-resolution AIF dynamic series of both the LV and RV during rest perfusion imaging, and the PTT was measured as the time (in seconds) between the centroid of the left (LV) and right ventricle (RV) indicator dilution curves. Results: Patients (N = 294) were followed-up for median 2.0 years during which 37 patients (12.6%) had at least one MACE event. On univariate Cox regression analysis there was a significant association between PTT and MACE (Hazard ratio (HR) 1.16, 95% confidence interval (CI) 1.08–1.25, P = 0.0001). There was also significant association between PTT and heart failure hospitalisation (HR 1.15, 95% CI 1.02–1.29, P = 0.02) and moderate correlation between PTT and N-terminal pro B-type natriuretic peptide (NT-proBNP, r = 0.51, P < 0.001). PTT remained predictive of MACE after adjustment for clinical and imaging factors but was no longer significant once adjusted for NT-proBNP. Conclusions: PTT measured automatically during CMR perfusion imaging in patients with recent onset non-ischaemic heart failure is predictive of MACE and in particular heart failure hospitalisation. PTT derived in this way may be a non-invasive marker of haemodynamic congestion in heart failure and future studies are required to establish if prolonged PTT identifies those who may warrant closer follow-up or medicine optimisation to reduce the risk of future adverse events. [ABSTRACT FROM AUTHOR]

Purpose: Guidelines recommend measuring myocardial extracellular volume (ECV) using T1‐mapping before and 10–30 min after contrast agent administration. Data are then analyzed using a linear model (LM), which assumes fast water exchange (WX) between the ECV and cardiomyocytes. We investigated whether limited WX influences ECV measurements in patients with severe aortic stenosis (AS). Methods: Twenty‐five patients with severe AS and 5 healthy controls were recruited. T1 measurements were made on a 3 T Siemens system using a multiparametric saturation‐recovery single‐shot acquisition (a) before contrast; (b) 4 min post 0.05 mmol/kg gadobutrol; and (c) 4 min, (d) 10 min, and (e) 30 min after an additional gadobutrol dose (0.1 mmol/kg). Three LM‐based ECV estimates, made using paired T1 measurements (a and b), (a and d), and (a and e), were compared to ECV estimates made using all 5 T1 measurements and a two‐site exchange model (2SXM) accounting for WX. Results: Median (range) ECV estimated using the 2SXM model was 25% (21%–39%) for patients and 26% (22%–29%) for controls. ECV estimated in patients using the LM at 10 min following a cumulative contrast dose of 0.15 mmol/kg was 21% (17%–32%) and increased significantly to 22% (19%–35%) at 30 min (p = 0.0001). ECV estimated using the LM was highest following low dose gadobutrol, 25% (19%–38%). Conclusion: Current guidelines on contrast agent dose for ECV measurements may lead to underestimated ECV in patients with severe AS because of limited WX. Use of a lower contrast agent dose may mitigate this effect. [ABSTRACT FROM AUTHOR]

Background: Determination of myocardial blood flow (MBF) with MRI is usually performed with dynamic contrast enhanced imaging (MBFDCE). MBF can also be determined from coronary sinus blood flow (MBFCS), which has the advantage of being a noncontrast technique. However, comparative studies of MBFDCE and MBFCS in large cohorts are lacking. Purpose: To compare MBFCS and MBFDCE in a large cohort. Study Type: Prospective, sequence‐comparison study. Population: 147 patients with type 2 diabetes mellitus (age: 56+/−12 years; 106 male; diabetes duration: 12.9+/−8.1 years), and 25 age‐matched controls. Field Strength/Sequences: 1.5 Tesla scanner. Saturation recovery sequence for MBFDCE vs. phase‐contrast gradient‐echo pulse sequence (free‐breathing) for MBFCS. Assessment: MBFDCE and MBFCS were determined at rest and during coronary dilatation achieved by administration of adenosine at 140 μg/kg/min. Myocardial perfusion reserve (MPR) was calculated as the stress/rest ratio of MBF values. Coronary sinus flow was determined twice in the same imaging session for repeatability assessment. Statistical Tests: Agreement between MBFDCE and MBFCS was assessed with Bland and Altman's technique. Repeatability was determined from single‐rater random intraclass and repeatability coefficients. Results: Rest and stress flows, including both MBFDCE and MBFCS values, ranged from 33 to 146 mL/min/100 g and 92 to 501 mL/min/100 g, respectively. Intraclass and repeatability coefficients for MBFCS were 0.95 (CI 0.90; 0.95) and 5 mL/min/100 g. In Bland–Altman analysis, mean bias at rest was –1.1 mL/min/100 g (CI −3.1; 0.9) with limits of agreement of −27 and 24.8 mL/min/100 g. Mean bias at stress was 6.3 mL/min/100 g (CI −1.1; 14.1) with limits of agreement of −86.9 and 99.9. Mean bias of MPR was 0.11 (CI: −0.02; 0.23) with limits of agreement of −1.43 and 1.64. Conclusion: MBF may be determined from coronary sinus blood flow, with acceptable bias, but relatively large limits of agreement, against the reference of MBFDCE. Level of Evidence: 1 Technical Efficacy Stage: 2 [ABSTRACT FROM AUTHOR]

Background: Patients with diabetes demonstrate early left ventricular systolic dysfunction. Notably reduced global longitudinal strain (GLS) is related to poor outcomes, the underlying pathophysiology is however still not clearly understood. We hypothesized that pathophysiologic changes with microvascular dysfunction and interstitial fibrosis contribute to reduced strain. Methods: 211 patients with type 2 diabetes and 25 control subjects underwent comprehensive cardiovascular phenotyping by magnetic resonance imaging. Myocardial blood flow (MBF), perfusion reserve (MPR), extracellular volume (ECV), and 3D feature tracking GLS and global circumferential (GCS) and radial strain (GRS) were quantified. Results: Patients (median age 57 [IQR 50, 67] years, 70% males) had a median diabetes duration of 12 [IQR 6, 18] years. Compared to control subjects GLS, GCS, and GRS were reduced in the total diabetes cohort, and GLS was also reduced in the sub-group of patients without diabetic complications compared to control subjects (controls − 13.9 ± 2.0%, total cohort − 11.6 ± 3.0%; subgroup − 12.3 ± 2.6%, all p < 0.05). Reduced GLS, but not GCS or GRS, was associated with classic diabetes complications of albuminuria (UACR ≥ 30 mg/g) [β (95% CI) 1.09 (0.22–1.96)] and autonomic neuropathy [β (95% CI) 1.43 (0.54–2.31)] but GLS was not associated with retinopathy or peripheral neuropathy. Independently of ECV, a 10% increase in MBF at stress and MPR was associated with higher GLS [multivariable regression adjusted for age, sex, hypertension, smoking, and ECV: MBF stress (β (95% CI) − 0.2 (− 0.3 to − 0.08), MPR (β (95% CI) − 0.5 (− 0.8 to − 0.3), p < 0.001 for both]. A 10% increase in ECV was associated with a decrease in GLS in univariable [β (95% CI) 0.6 (0.2 to 1.1)] and multivariable regression, but this was abolished when adjusted for MPR [multivariable regression adjusted for age, sex, hypertension, smoking, and MPR (β (95% CI) 0.1 (− 0.3 to 0.6)]. On the receiver operating characteristics curve, GLS showed a moderate ability to discriminate a significantly lowered stress MBF (AUC 0.72) and MPR (AUC 0.73). Conclusions: Myocardial microvascular dysfunction was independent of ECV, a biomarker of myocardial fibrosis, associated with GLS. Further, 3D GLS could be a potential screening tool for myocardial microvascular dysfunction. Future directions should focus on confirming these results in longitudinal and/or interventional studies. [ABSTRACT FROM AUTHOR]

Purpose: DTI characterizes tissue microstructure and provides proxy measures of nerve health. Echo‐planar imaging is a popular method of acquiring DTI but is susceptible to various artifacts (e.g., susceptibility, motion, and eddy currents), which may be ameliorated via preprocessing. There are many pipelines available but limited data comparing their performance, which provides the rationale for this study. Methods: DTI was acquired from the upper limb of heathy volunteers at 3T in blip‐up and blip‐down directions. Data were independently corrected using (i) FSL's TOPUP & eddy, (ii) FSL's TOPUP, (iii) DSI Studio, and (iv) TORTOISE. DTI metrics were extracted from the median, radial, and ulnar nerves and compared (between pipelines) using mixed‐effects linear regression. The geometric similarity of corrected b = 0 images and the slice matched T1‐weighted (T1w) images were computed using the Sörenson‐Dice coefficient. Results: Without preprocessing, the similarity coefficient of the blip‐up and blip‐down datasets to the T1w was 0·80 and 0·79, respectively. Preprocessing improved the geometric similarity by 1% with no difference between pipelines. Compared to TOPUP & eddy, DSI Studio and TORTOISE generated 2% and 6% lower estimates of fractional anisotropy, and 6% and 13% higher estimates of radial diffusivity, respectively. Estimates of anisotropy from TOPUP & eddy versus TOPUP were not different but TOPUP reduced radial diffusivity by 3%. The agreement of DTI metrics between pipelines was poor. Conclusions: Preprocessing DTI from the upper limb improves geometric similarity but the choice of the pipeline introduces clinically important variability in diffusion parameter estimates from peripheral nerves. [ABSTRACT FROM AUTHOR]

Left ventricular fibrosis can be identified by late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) in some veteran athletes. We aimed to investigate prevalence of ventricular fibrosis in veteran athletes and associations with cardiac arrhythmia. 50 asymptomatic male endurance athletes were recruited. They underwent CMR imaging including volumetric analysis, bright blood (BB) and dark blood (DB) LGE, motion corrected (MOCO) quantitative stress and rest perfusion and T1/T2/extracellular volume mapping. Athletes underwent 12-lead electrocardiogram (ECG) and 24-h ECG. Myocardial fibrosis was identified in 24/50 (48%) athletes. All fibrosis was mid-myocardial in the basal-lateral left ventricular wall. Blood pressure was reduced in athletes without fibrosis compared to controls, but not athletes with fibrosis. Fibrotic areas had longer T2 time (44 ± 4 vs. 40 ± 2 ms, p < 0.0001) and lower rest myocardial blood flow (MBF, 0.5 ± 0.1 vs. 0.6 ± 0.1 ml/g/min, p < 0.0001). On 24-h ECG, athletes with fibrosis had greater burden of premature ventricular beats (0.3 ± 0.6 vs. 0.05 ± 0.2%, p = 0.03), with higher prevalence of ventricular couplets and triplets (33 vs. 8%, p = 0.02). In veteran endurance athletes, myocardial fibrosis is common and associated with an increased burden of ventricular ectopy. Possible mechanisms include inflammation and blood pressure. Further studies are needed to establish whether fibrosis increases risk of malignant arrhythmic events. [ABSTRACT FROM AUTHOR]

The early career professionals in the field of Cardiovascular Magnetic Resonance (CMR) face unique challenges and hurdles while establishing their careers in the field. The Society for Cardiovascular Magnetic Resonance (SCMR) has expanded the role of the early career section within the society to foster the careers of future CMR leaders. This paper aims to describe the obstacles and available opportunities for the early career CMR professionals worldwide. Societal opportunities and actions targeted at the professional advancement of the early career CMR imagers are needed to ensure continuous growth of CMR as an imaging modality globally. [ABSTRACT FROM AUTHOR]

Background and Objectives: Cardiovascular magnetic resonance (CMR) is emerging as an important imaging tool for sub-phenotyping and estimating left ventricular (LV) filling pressure (LVFP). The N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) is released from cardiac myocytes in response to mechanical load and wall stress. This study sought to investigate if CMR-derived LVFP is associated with the serum levels of NT-proBNP and, in addition, if it provides any incremental prognostic value in heart failure (HF). Materials and Methods: This study recruited 380 patients diagnosed with HF who underwent same-day CMR and clinical assessment between February 2018 and January 2020. CMR-derived LVFP was calculated, as previously, from long- and short-axis cines. During CMR assessment, serum NT-proBNP was measured. The pathological cut-offs were defined as follows: NT-proBNP ≥ 125 pg/mL and CMR LVFP > 15 mmHg. The incidence of HF hospitalisation was treated as a clinical outcome. Results: In total, 305 patients had NT-proBNP ≥ 125 pg/mL. Patients with raised NT-proBNP were older (54 ± 14 vs. 64 ± 11 years, p < 0.0001). Patients with raised NT-proBNP had higher LV volumes and mass. In addition, CMR LVFP was higher in patients with raised NT-proBNP (13.2 ± 2.6 vs. 15.4 ± 3.2 mmHg, p < 0.0001). The serum levels of NT-proBNP were associated with CMR-derived LVFP (R = 0.42, p < 0.0001). In logistic regression analysis, this association between NT-proBNP and CMR LVFP was independent of all other CMR variables, including LV ejection fraction, LV mass, and left atrial volume (coefficient = 2.02, p = 0.002). CMR LVFP demonstrated an independent association with the incidence of HF hospitalisation above NT-proBNP (hazard ratio 2.7, 95% confidence interval 1.2 to 6, p = 0.01). Conclusions: A CMR-modelled LVFP is independently associated with serum NT-proBNP levels. Importantly, it provides an incremental prognostic value over and above serum NT-proBNP levels. [ABSTRACT FROM AUTHOR]

The article examines the perspective of the Society for Cardiovascular Magnetic Resonance on the 2023 multimodality appropriate use criteria (AUC) for the detection and risk assessment of chronic coronary disease (CCD). Topics discussed include changes from the 2013 AUC for multimodality imaging in stable ischemic heart disease, 2023 AUC for multimodality imaging in CCD in the context of other guidelines, imaging modalities, and specific indications for symptomatic and asymptomatic patients.

Aims: Left ventricular filling pressure (LVFP) can be estimated from cardiovascular magnetic resonance (CMR). We aimed to investigate whether CMR‐derived LVFP is associated with signs, symptoms, and prognosis in patients with recently diagnosed heart failure (HF). Methods and results: This study recruited 454 patients diagnosed with HF who underwent same‐day CMR and clinical assessment between February 2018 and January 2020. CMR‐derived LVFP was calculated, as previously, from long‐ and short‐axis cines. CMR‐derived LVFP association with symptoms and signs of HF was investigated. Patients were followed for median 2.9 years (interquartile range 1.5–3.6 years) for major adverse cardiovascular events (MACE), defined as the composite of cardiovascular death, HF hospitalization, non‐fatal stroke, and non‐fatal myocardial infarction. The mean age was 62 ± 13 years, 36% were female (n = 163), and 30% (n = 135) had raised LVFP. Forty‐seven per cent of patients had an ejection fraction < 40% during CMR assessment. Patients with raised LVFP were more likely to have pleural effusions [hazard ratio (HR) 3.2, P = 0.003], orthopnoea (HR 2.0, P = 0.008), lower limb oedema (HR 1.7, P = 0.04), and breathlessness (HR 1.7, P = 0.01). Raised CMR‐derived LVFP was associated with a four‐fold risk of HF hospitalization (HR 4.0, P < 0.0001) and a three‐fold risk of MACE (HR 3.1, P < 0.0001). In the multivariable model, raised CMR‐derived LVFP was independently associated with HF hospitalization (adjusted HR 3.8, P = 0.0001) and MACE (adjusted HR 3.0, P = 0.0001). Conclusions: Raised CMR‐derived LVFP is strongly associated with symptoms and signs of HF. In addition, raised CMR‐derived LVFP is independently associated with subsequent HF hospitalization and MACE. [ABSTRACT FROM AUTHOR]

Background: Advances in four-dimensional flow cardiovascular magnetic resonance (4D flow CMR) have allowed quantification of left ventricular (LV) and right ventricular (RV) blood flow. We aimed to (1) investigate age and sex differences of 4D flow CMR-derived LV and RV relative flow components and kinetic energy (KE) parameters indexed to end-diastolic volume (KEiEDV) in healthy subjects; and (2) assess the effects of age and sex on these parameters. Methods: We performed 4D flow analysis in 163 healthy participants (42% female; mean age 43 ± 13 years) of a prospective registry study (NCT03217240) who were free of cardiovascular diseases. Relative flow components (direct flow, retained inflow, delayed ejection flow, residual volume) and multiple phasic KEiEDV (global, peak systolic, average systolic, average diastolic, peak E-wave, peak A-wave) for both LV and RV were analysed. Results: Compared with men, women had lower median LV and RV residual volume, and LV peak and average systolic KEiEDV, and higher median values of RV direct flow, RV global KEiEDV, RV average diastolic KEiEDV, and RV peak E-wave KEiEDV. ANOVA analysis found there were no differences in flow components, peak and average systolic, average diastolic and global KEiEDV for both LV and RV across age groups. Peak A-wave KEiEDV increased significantly (r = 0.458 for LV and 0.341 for RV), whereas peak E-wave KEiEDV (r = − 0.355 for LV and − 0.318 for RV), and KEiEDV E/A ratio (r = − 0.475 for LV and − 0.504 for RV) decreased significantly, with age. Conclusion: These data using state-of-the-art 4D flow CMR show that biventricular flow components and kinetic energy parameters vary significantly by age and sex. Age and sex trends should be considered in the interpretation of quantitative measures of biventricular flow. Clinical trial registration https://www.clinicaltrials.gov. Unique identifier: NCT03217240. [ABSTRACT FROM AUTHOR]

Left ventricular fibrosis can be identified by late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) in some veteran athletes. We aimed to investigate prevalence of ventricular fibrosis in veteran athletes and associations with cardiac arrhythmia. 50 asymptomatic male endurance athletes were recruited. They underwent CMR imaging including volumetric analysis, bright blood (BB) and dark blood (DB) LGE, motion corrected (MOCO) quantitative stress and rest perfusion and T1/T2/extracellular volume mapping. Athletes underwent 12-lead electrocardiogram (ECG) and 24-h ECG. Myocardial fibrosis was identified in 24/50 (48%) athletes. All fibrosis was mid-myocardial in the basal-lateral left ventricular wall. Blood pressure was reduced in athletes without fibrosis compared to controls, but not athletes with fibrosis. Fibrotic areas had longer T2 time (44 ± 4 vs. 40 ± 2 ms, p < 0.0001) and lower rest myocardial blood flow (MBF, 0.5 ± 0.1 vs. 0.6 ± 0.1 ml/g/min, p < 0.0001). On 24-h ECG, athletes with fibrosis had greater burden of premature ventricular beats (0.3 ± 0.6 vs. 0.05 ± 0.2%, p = 0.03), with higher prevalence of ventricular couplets and triplets (33 vs. 8%, p = 0.02). In veteran endurance athletes, myocardial fibrosis is common and associated with an increased burden of ventricular ectopy. Possible mechanisms include inflammation and blood pressure. Further studies are needed to establish whether fibrosis increases risk of malignant arrhythmic events. [ABSTRACT FROM AUTHOR]

Background: When feasible, guidelines recommend mitral valve repair (MVr) over mitral valve replacement (MVR) to treat primary mitral regurgitation (MR), based upon historic outcome studies and transthoracic echocardiography (TTE) reverse remodeling studies. Cardiovascular magnetic resonance (CMR) offers reference standard biventricular assessment with superior MR quantification compared to TTE. Using serial CMR in primary MR patients, we aimed to investigate cardiac reverse remodeling and residual MR post-MVr vs MVR with chordal preservation. Methods: 83 patients with ≥ moderate-severe MR on TTE were prospectively recruited. 6-min walk tests (6MWT) and CMR imaging including cine imaging, aortic/pulmonary through-plane phase contrast imaging, T1 maps and late-gadolinium-enhanced (LGE) imaging were performed at baseline and 6 months after mitral surgery or watchful waiting (control group). Results: 72 patients completed follow-up (Controls = 20, MVr = 30 and MVR = 22). Surgical groups demonstrated comparable baseline cardiac indices and co-morbidities. At 6-months, MVr and MVR groups demonstrated comparable improvements in 6MWT distances (+ 57 ± 54 m vs + 64 ± 76 m respectively, p = 1), reduced indexed left ventricular end-diastolic volumes (LVEDVi; − 29 ± 21 ml/m2 vs − 37 ± 22 ml/m2 respectively, p = 0.584) and left atrial volumes (− 23 ± 30 ml/m2 and − 39 ± 26 ml/m2 respectively, p = 0.545). At 6-months, compared with controls, right ventricular ejection fraction was poorer post-MVr (47 ± 6.1% vs 53 ± 8.0% respectively, p = 0.01) compared to post-MVR (50 ± 5.7% vs 53 ± 8.0% respectively, p = 0.698). MVR resulted in lower residual MR-regurgitant fraction (RF) than MVr (12 ± 8.0% vs 21 ± 11% respectively, p = 0.022). Baseline and follow-up indices of diffuse and focal myocardial fibrosis (Native T1 relaxation times, extra-cellular volume and quantified LGE respectively) were comparable between groups. Stepwise multiple linear regression of indexed variables in the surgical groups demonstrated baseline indexed mitral regurgitant volume as the sole multivariate predictor of left ventricular (LV) end-diastolic reverse remodelling, baseline LVEDVi as the most significant independent multivariate predictor of follow-up LVEDVi, baseline indexed LV end-systolic volume as the sole multivariate predictor of follow-up LV ejection fraction and undergoing MVR (vs MVr) as the most significant (p < 0.001) baseline multivariate predictor of lower residual MR. Conclusion: In primary MR, MVR with chordal preservation may offer comparable cardiac reverse remodeling and functional benefits at 6-months when compared to MVr. Larger, multicenter CMR studies are required, which if the findings are confirmed could impact future surgical practice. [ABSTRACT FROM AUTHOR]

Purpose: Tensor‐valued diffusion encoding can probe more specific features of tissue microstructure than what is available by conventional diffusion weighting. In this work, we investigate the technical feasibility of tensor‐valued diffusion encoding at high b‐values with q‐space trajectory imaging (QTI) analysis, in the human heart in vivo. Methods: Ten healthy volunteers were scanned on a 3T scanner. We designed time‐optimal gradient waveforms for tensor‐valued diffusion encoding (linear and planar) with second‐order motion compensation. Data were analyzed with QTI. Normal values and repeatability were investigated for the mean diffusivity (MD), fractional anisotropy (FA), microscopic FA (μFA), isotropic, anisotropic and total mean kurtosis (MKi, MKa, and MKt), and orientation coherence (Cc). A phantom, consisting of two fiber blocks at adjustable angles, was used to evaluate sensitivity of parameters to orientation dispersion and diffusion time. Results: QTI data in the left ventricular myocardium were MD = 1.62 ± 0.07 μm2/ms, FA = 0.31 ± 0.03, μFA = 0.43 ± 0.07, MKa = 0.20 ± 0.07, MKi = 0.13 ± 0.03, MKt = 0.33 ± 0.09, and Cc = 0.56 ± 0.22 (mean ± SD across subjects). Phantom experiments showed that FA depends on orientation dispersion, whereas μFA was insensitive to this effect. Conclusion: We demonstrated the first tensor‐valued diffusion encoding and QTI analysis in the heart in vivo, along with first measurements of myocardial μFA, MKi, MKa, and Cc. The methodology is technically feasible and provides promising novel biomarkers for myocardial tissue characterization. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether left atrial (LA) volume and left ventricular filling pressure (LVFP) assessed by cardiovascular magnetic resonance (CMR) change during adenosine delivered myocardial hyperaemia as part of a first-pass stress perfusion study. Methods and results: We enrolled 33 patients who had stress CMR. These patients had a baseline four-chamber cine and stress four-chamber cine, which was done at peak myocardial hyperaemic state after administering adenosine. The left and right atria were segmented in the end ventricular diastolic and systolic phases. Short-axis cine stack was segmented for ventricular functional assessment. At peak hyperaemic state, left atrial end ventricular systolic volume just before mitral valve opening increased significantly from baseline in all (91 ± 35ml vs. 81 ± 33ml, P = 0.0002), in males only (99 ± 35ml vs. 88 ± 33ml, P = 0.002) and females only (70 ± 26ml vs. 62 ± 22ml, P = 0.02). The right atrial end ventricular systolic volume increased less significantly from baseline (68 ± 21ml vs. 63 ± 20ml, P = 0.0448). CMR-derived LVFP (equivalent to pulmonary capillary wedge pressure) increased significantly at the peak hyperaemic state in all (15.1 ± 2.9mmHg vs. 14.4 ± 2.8mmHg, P = 0.0002), females only (12.9 ± 2.1mmHg vs. 12.3 ± 1.9mmHg, P = 0.029) and males only (15.9 ± 2.8mmHg vs. 15.2 ± 2.7mmHg, P = 0.002) cohorts. Conclusion: Left atrial volume assessment by CMR can measure acute and dynamic changes in preloading conditions on the left ventricle. During adenosine administered first-pass perfusion CMR, left atrial volume and LVFP rise significantly. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to design and evaluate a deep learning-based method to automatically predict the time-varying in-plane blood flow velocity within the cardiac cavities in long-axis cine MRI, validated against 4D flow. Methods: A convolutional neural network (CNN) was implemented, taking cine MRI as the input and the in-plane velocity derived from the 4D flow acquisition as the ground truth. The method was evaluated using velocity vector end-point error (EPE) and angle error. Additionally, the E/A ratio and diastolic function classification derived from the predicted velocities were compared to those derived from 4D flow. Results: For intra-cardiac pixels with a velocity > 5 cm/s, our method achieved an EPE of 8.65 cm/s and angle error of 41.27°. For pixels with a velocity > 25 cm/s, the angle error significantly degraded to 19.26°. Although the averaged blood flow velocity prediction was under-estimated by 26.69%, the high correlation (PCC = 0.95) of global time-varying velocity and the visual evaluation demonstrate a good agreement between our prediction and 4D flow data. The E/A ratio was derived with minimal bias, but with considerable mean absolute error of 0.39 and wide limits of agreement. The diastolic function classification showed a high accuracy of 86.9%. Conclusion: Using a deep learning-based algorithm, intra-cardiac blood flow velocities can be predicted from long-axis cine MRI with high correlation with 4D flow derived velocities. Visualization of the derived velocities provides adjunct functional information and may potentially be used to derive the E/A ratio from conventional CMR exams. [ABSTRACT FROM AUTHOR]

Background: Diffuse myocardial fibrosis and microvascular dysfunction are suggested to underlie cardiac dysfunction in patients with type 2 diabetes, but studies investigating their relative impact are lacking. We aimed to study imaging biomarkers of these and hypothesized that fibrosis and microvascular dysfunction would affect different phases of left ventricular (LV) diastole. Methods: In this cross-sectional study myocardial blood flow (MBF) at rest and adenosine-stress and perfusion reserve (MPR), as well as extracellular volume fraction (ECV), were determined with cardiovascular magnetic resonance (CMR) imaging in 205 patients with type 2 diabetes and 25 controls. Diastolic parameters included echocardiography-determined lateral e' and average E/e', and CMR-determined (rest and chronotropic-stress) LV early peak filling rate (ePFR), LV peak diastolic strain rate (PDSR), and left atrial (LA) volume changes. Results: In multivariable analysis adjusted for possible confounders including each other (ECV for blood flow and vice versa), a 10% increase of ECV was independently associated with ePFR/EDV (rest: β = − 4.0%, stress: β = − 7.9%), LAmax /BSA (rest: β = 4.8%, stress: β = 5.8%), and circumferential (β = − 4.1%) and radial PDSR (β = 0.07%/sec). A 10% stress MBF increase was associated with lateral e′ (β = 1.4%) and average E/e' (β = − 1.4%) and a 10% MPR increase to lateral e′ (β = 2.7%), and average E/e' (β = − 2.8%). For all the above, p < 0.05. No associations were found with longitudinal PDSR or left atrial total emptying fraction. Conclusion: In patients with type 2 diabetes, imaging biomarkers of microvascular dysfunction and diffuse fibrosis impacts diastolic dysfunction independently of each other. Microvascular dysfunction primarily affects early left ventricular relaxation. Diffuse fibrosis primarily affects diastasis. Trial registrationhttps://www.clinicaltrials.gov. Unique identifier: NCT02684331. Date of registration: February 18, 2016. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic that has affected nearly 600 million people to date across the world. While COVID-19 is primarily a respiratory illness, cardiac injury is also known to occur. Cardiovascular magnetic resonance (CMR) imaging is uniquely capable of characterizing myocardial tissue properties in-vivo, enabling insights into the pattern and degree of cardiac injury. The reported prevalence of myocardial involvement identified by CMR in the context of COVID-19 infection among previously hospitalized patients ranges from 26 to 60%. Variations in the reported prevalence of myocardial involvement may result from differing patient populations (e.g. differences in severity of illness) and the varying intervals between acute infection and CMR evaluation. Standardized methodologies in image acquisition, analysis, interpretation, and reporting of CMR abnormalities across would likely improve concordance between studies. This consensus document by the Society for Cardiovascular Magnetic Resonance (SCMR) provides recommendations on CMR imaging and reporting metrics towards the goal of improved standardization and uniform data acquisition and analytic approaches when performing CMR in patients with COVID-19 infection. [ABSTRACT FROM AUTHOR]

Peripheral neuropathy affects 1 in 10 adults over the age of 40 years. Given the absence of a reliable diagnostic test for peripheral neuropathy, there has been a surge of research into diffusion tensor imaging (DTI) because it characterises nerve microstructure and provides reproducible proxy measures of myelination, axon diameter, fibre density and organisation. Before researchers and clinicians can reliably use diffusion tensor imaging to assess the 'health' of the major nerves of the upper limb, we must understand the "normal" range of values and how they vary with experimental conditions. We searched PubMed, Embase, medRxiv and bioRxiv for studies which reported the findings of DTI of the upper limb in healthy adults. Four review authors independently triple extracted data. Using the meta suite of Stata 17, we estimated the normal fractional anisotropy (FA) and diffusivity (mean, MD; radial, RD; axial AD) values of the median, radial and ulnar nerve in the arm, elbow and forearm. Using meta-regression, we explored how DTI metrics varied with age and experimental conditions. We included 20 studies reporting data from 391 limbs, belonging to 346 adults (189 males and 154 females, ~ 1.2 M:1F) of mean age 34 years (median 31, range 20–80). In the arm, there was no difference in the FA (pooled mean 0.59 mm2/s [95% CI 0.57, 0.62]; I2 98%) or MD (pooled mean 1.13 × 10–3 mm2/s [95% CI 1.08, 1.18]; I2 99%) of the median, radial and ulnar nerves. Around the elbow, the ulnar nerve had a 12% lower FA than the median and radial nerves (95% CI − 0.25, 0.00) and significantly higher MD, RD and AD. In the forearm, the FA (pooled mean 0.55 [95% CI 0.59, 0.64]; I2 96%) and MD (pooled mean 1.03 × 10–3 mm2/s [95% CI 0.94, 1.12]; I2 99%) of the three nerves were similar. Multivariable meta regression showed that the b-value, TE, TR, spatial resolution and age of the subject were clinically important moderators of DTI parameters in peripheral nerves. We show that subject age, as well as the b-value, TE, TR and spatial resolution are important moderators of DTI metrics from healthy nerves in the adult upper limb. The normal ranges shown here may inform future clinical and research studies. [ABSTRACT FROM AUTHOR]

Background: Cardiac MRI is an important imaging tool in congenital cardiac disease, but its use has been limited in the neonatal population as general anesthesia has been needed for breath‐holding. Technological advances in four‐dimensional (4D) flow MRI have now made nonsedated free‐breathing acquisition protocols a viable clinical option, but the method requires prospective validation in neonates. Purpose: To test the feasibility of compressed sensing (CS) 4D flow MRI in the neonatal population and to compare with standard previously validated two‐dimensional (2D) phase‐contrast (PC) flow MRI. Study type: Prospective, cohort, image quality. Population: A total of 14 healthy neonates (median [range] age: 2.5 [0–80] days; 8 male). Field Strength and Sequence: Noncontrast 2D cine gradient echo sequence with through‐plane velocity encoding (PC) sequence and compressed sensing (CS) three‐dimensional (3D), time‐resolved, cine phase‐contrast MRI with 3D velocity‐encoding (4D flow MRI) at 3 T. Assessment: Aortic 2D PC, and aortic, pulmonary trunk and superior vena cava CS 4D flow MRI were acquired using the feed and wrap technique (nonsedated) and quantified using commercially available software. Aortic flow and peak velocity were compared between methods. Internal consistency of 4D flow MRI was determined by comparing mean forward flow of the main pulmonary artery (MPA) vs. the sum of left and right pulmonary artery flows (LPA and RPA) and by comparing mean ascending aorta forward flow (AAo) vs. the sum of superior vena cava (SVC) and descending aorta flows (DAo). Statistical Tests: Flow and peak‐velocity comparisons were assessed using paired t‐tests, with P < 0.05 considered significant, and Bland–Altman analysis. Interobserver and intraobserver agreement and internal consistency were analyzed by intraclass correlation co‐efficient (ICC). Results: There was no statistically significant difference between ascending aortic forward flow between 2D PC and CS 4D Flow MRI (P = 0.26) with a bias of 0.11 mL (−0.59 to 0.82 mL) nor peak velocity (P = 0.11), with a bias of −5 cm/sec and (−26 to 16 cm/sec). There was excellent interobserver and intraobserver agreement for each vessel (interobserver ICC: AAo 1.00; DAo 0.94, SVC 0.90, MPA 0.99, RPA 0.98, LPA 0.96; intraobserver ICC: AAo 1.00; DAo 0.99, SVC 0.98, MPA 1.00, RPA 1.00, LPA 0.99). Internal consistency measures showed excellent agreement for both mean forward flow of main pulmonary artery vs. the sum of left and right pulmonary arteries (ICC: 0.95) and mean ascending aorta forward flow vs. the sum of superior vena cava and descending aorta flows (ICC: 1.00). Conclusion: Sedation‐free neonatal feed and wrap MRI is well tolerated and feasible. CS 4D flow MRI quantification is similar to validated 2D PC free‐breathing imaging with excellent interobserver and intraobserver agreement. Evidence Level: 1 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Objective: Subclinical systemic sclerosis (SSc) primary heart involvement is commonly described. Whether these findings progress over time is not clear. The study aimed to investigate cardiovascular magnetic resonance (CMR) interval change of subclinical SSc primary heart involvement. Methods: Patients with SSc with no cardiovascular disease underwent two CMR scans that included T1 mapping and quantitative stress perfusion. The CMR change (mean difference) and association between CMR measures and clinical phenotype were assessed. The study had a prospective design. Results: Thirty‐one patients with SSc participated, with a median (interquartile range) follow‐up of 33 (17‐37) months (10 [32%] in the diffuse subset, 16 [52%] with interstitial lung disease [ILD], and 11 [29%] who were Scl‐70+). Four of thirty‐one patients had focal late gadolinium enhancement (LGE) at visit 1; one of four had an increase in LGE scar mass between visits. Two patients showed new focal LGE at visit 2. No change in other CMR indices was noted. The three patients with SSc with increased or new LGE at visit 2 had diffuse cutaneous SSc with ILD, and two were Scl‐70+. A reduction in forced vital capacity and total lung capacity was associated with a reduction in left ventricular ejection fraction (ρ = 0.413, P = 0.021; ρ = 0.335, P = 0.07) and myocardial perfusion reserve (MPR) (ρ = 0.543, P = 0.007; ρ = 0.627, P = 0.002). An increase in the N‐terminal pro–brain natriuretic peptide level was associated with a reduction in MPR (ρ = −0.448, P = 0.042). Patients on disease‐modifying antirheumatic drugs (DMARDs) had an increase in native T1 (mean [SD] 1208 [65] vs. 1265 [56] milliseconds, P = 0.008). No other clinically meaningful CMR change in patients receiving DMARDs or vasodilators was noted. Conclusion: Serial CMR detects interval subclinical SSc primary heart involvement progression; however, this study suggests abnormalities remain largely stable with follow‐up. [ABSTRACT FROM AUTHOR]

Background. Ischaemia with nonobstructive coronary arteries is most commonly caused by coronary microvascular dysfunction but remains difficult to diagnose without invasive testing. Myocardial blood flow (MBF) can be quantified noninvasively on stress perfusion cardiac magnetic resonance (CMR) or positron emission tomography but neither is routinely used in clinical practice due to practical and technical constraints. Quantification of coronary sinus (CS) flow may represent a simpler method for CMR MBF quantification. 4D flow CMR offers comprehensive intracardiac and transvalvular flow quantification. However, it is feasibility to quantify MBF remains unknown. Methods. Patients with acute myocardial infarction (MI) and healthy volunteers underwent CMR. The CS contours were traced from the 2-chamber view. A reformatted phase contrast plane was generated through the CS, and flow was quantified using 4D flow CMR over the cardiac cycle and normalised for myocardial mass. MBF and resistance (MyoR) was determined in ten healthy volunteers, ten patients with myocardial infarction (MI) without microvascular obstruction (MVO), and ten with known MVO. Results. MBF was quantified in all 30 subjects. MBF was highest in healthy controls (123.8 ± 48.4 mL/min), significantly lower in those with MI (85.7 ± 30.5 mL/min), and even lower in those with MI and MVO (67.9 ± 29.2 mL/min/) (P < 0.01 for both differences). Compared with healthy controls, MyoR was higher in those with MI and even higher in those with MI and MVO (0.79 (±0.35) versus 1.10 (±0.50) versus 1.50 (±0.69), P = 0.02). Conclusions. MBF and MyoR can be quantified from 4D flow CMR. Resting MBF was reduced in patients with MI and MVO. [ABSTRACT FROM AUTHOR]

Aims The 2016 European Society of Cardiology Heart Failure Guidelines defined a new category: heart failure with mid-range ejection fraction (HFmrEF) of 40–49%. This new category was highlighted as having limited evidence and research was advocated into underlying characteristics, pathophysiology, and diagnosis. We used multi-parametric cardiovascular magnetic resonance (CMR) to define the cardiac phenotype of presumed non-ischaemic HFmrEF. Methods and results Patients (N = 300, 62.7 ± 13 years, 63% males) with a clinical diagnosis of heart failure with no angina symptoms, history of myocardial infarction, or coronary intervention were prospectively recruited. Patients underwent clinical assessment and CMR including T1 mapping, extracellular volume (ECV) mapping, late gadolinium enhancement, and measurement of myocardial blood flow at rest and maximal hyperaemia. Of 273 patients in the final analysis, 93 (34%) patients were categorized as HFmrEF, 46 (17%) as heart failure with preserved ejection fraction (HFpEF), and 134 (49%) as heart failure with reduced ejection fraction (HFrEF). Nineteen (20%) patients with HFmrEF had evidence of occult ischaemic heart disease. Diffuse fibrosis and hyperaemic myocardial blood flow were similar in HFmrEF and HFpEF, but HFmrEF showed significantly lower native T1 (1311 ± 32 vs. 1340 ± 45 ms, P < 0.001), ECV (24.6 ± 3.2 vs. 26.3 ± 3.1%, P < 0.001), and higher myocardial perfusion reserve (2.75 ± 0.84 vs. 2.28 ± 0.84, P < 0.001) compared with HFrEF. Conclusion Patients with HFmrEF share most phenotypic characteristics with HFpEF, including the degree of microvascular impairment and fibrosis, but have a high prevalence of occult ischaemic heart disease similar to HFrEF. Further work is needed to confirm how the phenotype of HFmrEF responds to medical therapy. [ABSTRACT FROM AUTHOR]

Objectives: In patients of advanced age, the feasibility of myocardial ischemia testing might be limited by age-related comorbidities and falling compliance abilities. Therefore, we aimed to test the accuracy of 3D cardiac magnetic resonance (CMR) stress perfusion in the elderly population as compared to reference standard fractional flow reserve (FFR). Methods: Fifty-six patients at age 75 years or older (mean age 79 ± 4 years, 35 male) underwent 3D CMR perfusion imaging and invasive coronary angiography with FFR in 5 centers using the same study protocol. The diagnostic accuracy of CMR was compared to a control group of 360 patients aged below 75 years (mean age 61 ± 9 years, 262 male). The percentage of myocardial ischemic burden (MIB) relative to myocardial scar burden was further analyzed using semi-automated software. Results: Sensitivity, specificity, and positive and negative predictive values of 3D perfusion CMR deemed similar for both age groups in the detection of hemodynamically relevant (FFR < 0.8) stenosis (≥ 75 years: 86%, 83%, 92%, and 75%; < 75 years: 87%, 80%, 82%, and 85%; p > 0.05 all). While MIB was larger in the elderly patients (15% ± 17% vs. 9% ± 13%), the diagnostic accuracy of 3D CMR perfusion was high in both elderly and non-elderly populations to predict pathological FFR (AUC: 0.906 and 0.866). Conclusions: 3D CMR perfusion has excellent diagnostic accuracy for the detection of hemodynamically relevant coronary stenosis, independent of patient age. Key Points: • The increasing prevalence of coronary artery disease in elderly populations is accompanied with a larger ischemic burden of the myocardium as compared to younger individuals. • 3D cardiac magnetic resonance perfusion imaging predicts pathological fractional flow reserve in elderly patients aged ≥ 75 years with high diagnostic accuracy. • Ischemia testing with 3D CMR perfusion imaging has similarly high accuracy in the elderly as in younger patients and it might be particularly useful when other non-invasive techniques are limited by aging-related comorbidities and falling compliance abilities. [ABSTRACT FROM AUTHOR]

The Society for Cardiovascular Magnetic Resonance (SCMR) recommendations for training and competency of cardiovascular magnetic resonance (CMR) technologists document will define the knowledge, experiences and skills required for a technologist to be competent in CMR imaging. By providing a framework for CMR training and competency the overarching goal is to promote the performance of high-quality CMR and to foster the increased adoption of CMR into clinical care. [ABSTRACT FROM AUTHOR]

Objective: We investigated if women with gestational diabetes mellitus (GDM) in the third trimester of pregnancy exhibit adverse cardiac alterations in myocardial energetics, function, or tissue characteristics.Research Design and Methods: Thirty-eight healthy, pregnant women and 30 women with GDM were recruited. Participants underwent phosphorus MRS and cardiovascular magnetic resonance for assessment of myocardial energetics (phosphocreatine [PCr] to ATP ratio), tissue characteristics, biventricular volumes and ejection fractions, left ventricular (LV) mass, global longitudinal shortening (GLS), and mitral in-flow E-wave to A-wave ratio.Results: Participants were matched for age, gestational age, and ethnicity. The following data are reported as mean ± SD. The women with GDM had higher BMI (27 ± 4 vs. 33 ± 5 kg/m2; P = 0.0001) and systolic (115 ± 11 vs. 121 ± 13 mmHg; P = 0.04) and diastolic (72 ± 7 vs. 76 ± 9 mmHg; P = 0.04) blood pressures. There was no difference in N-terminal pro-brain natriuretic peptide concentrations between the groups. The women with GDM had lower myocardial PCr to ATP ratio (2.2 ± 0.3 vs. 1.9 ± 0.4; P < 0.0001), accompanied by lower LV end-diastolic volumes (76 ± 12 vs. 67 ± 11 mL/m2; P = 0.002) and higher LV mass (90 ± 13 vs. 103 ± 18 g; P = 0.001). Although ventricular ejection fractions were similar, the GLS was reduced in women with GDM (-20% ± 3% vs. -18% ± 3%; P = 0.008).Conclusions: Despite no prior diagnosis of diabetes, women with obesity and GDM manifest impaired myocardial contractility and higher LV mass, associated with reductions in myocardial energetics in late pregnancy compared with lean women with healthy pregnancy. These findings may aid our understanding of the long-term cardiovascular risks associated with GDM. [ABSTRACT FROM AUTHOR]

Background: Despite advancements in percutaneous coronary intervention, a significant proportion of ST-elevation myocardial infarction (STEMI) survivors develop long-term adverse left ventricular (LV) remodelling, which is associated with poor prognosis. Adverse remodelling is difficult to predict, however four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) can measure various aspects of LV intra-cavity flow beyond LV ejection fraction and is well equipped for exploring the underlying mechanical processes driving remodelling. The aim for this study was to compare acute 4D flow CMR parameters between patients who develop adverse remodelling with patients who do not. Methods: Fifty prospective 'first-event' STEMI patients underwent CMR 5 days post-reperfusion, which included cine-imaging, and 4D flow for assessing in-plane kinetic energy (KE), residual volume, peak-E and peak-A wave KE (indexed for LV end-diastolic volume [LVEDV]). All subjects underwent follow-up cine CMR imaging at 12 months to identify adverse remodelling (defined as 20% increase in LVEDV from baseline). Quantitative variables were compared using unpaired student's t-test. Tests were deemed statistically significant when p < 0.05. Results: Patients who developed adverse LV remodelling by 12 months had significantly higher in-plane KE (54 ± 12 vs 42 ± 10%, p = 0.02), decreased proportion of direct flow (27 ± 9% vs 11 ± 4%, p < 0.01), increased proportion of delayed ejection flow (22 ± 9% vs 12 ± 2, p < 0.01) and increased proportion of residual volume after 2 consecutive cardiac cycles (64 ± 14 vs 34 ± 14%, p < 0.01), in their acute scan. Conclusion: Following STEMI, increased in-plane KE, reduced direct flow and increased residual volume in the acute scan were all associated with adverse LV remodelling at 12 months. Our results highlight the clinical utility of acute 4D flow in prognostic stratification in patients following myocardial infarction. [ABSTRACT FROM AUTHOR]

Background: Left atrial (LA) dilatation is linked to cardiovascular disease and atrial fibrillation but its associations in athletes are unknown. The authors investigated whether aerobic fitness and clinical parameters are associated with LA dilatation and emptying fraction (EF) in endurance athletes. Materials & methods: 65 endurance athletes underwent cardiovascular magnetic resonance to assess LA size and function along with fitness assessment. 25 sedentary controls underwent an identical cardiovascular magnetic resonance protocol. Results: In athletes, LA volume index was elevated, while total and passive LAEFs were decreased versus sedentary controls. Increasing age and maximal oxygen uptake were associated with LA volume index. Only older age was associated with decreased total LAEF. Conclusion: LA dilatation in athletes is associated with increasing age and aerobic fitness rather than conventional cardiovascular risk factors. [ABSTRACT FROM AUTHOR]

Background: Intramyocardial hemorrhage (IMH) following ST‐elevation myocardial infarction (STEMI) is associated with poor prognosis. In cardiac magnetic resonance (MR), T2* mapping is the reference standard for detecting IMH while cardiac diffusion tensor imaging (cDTI) can characterize myocardial architecture via fractional anisotropy (FA) and mean diffusivity (MD) of water molecules. The value of cDTI in the detection of IMH is not currently known. Hypothesis: cDTI can detect IMH post‐STEMI. Study Type: Prospective. Subjects: A total of 50 patients (20% female) scanned at 1‐week (V1) and 3‐month (V2) post‐STEMI. Field Strength/Sequence: A 3.0 T; inversion‐recovery T1‐weighted‐imaging, multigradient‐echo T2* mapping, spin‐echo cDTI. Assessment: T2* maps were analyzed to detect IMH (defined as areas with T2* < 20 msec within areas of infarction). cDTI images were co‐registered to produce averaged diffusion‐weighted‐images (DWIs), MD, and FA maps; hypointense areas were manually planimetered for IMH quantification. Statistics: On averaged DWI, the presence of hypointense signal in areas matching IMH on T2* maps constituted to true‐positive detection of iron. Independent samples t‐tests were used to compare regional cDTI values. Results were considered statistically significant at P ≤ 0.05. Results: At V1, 24 patients had IMH on T2*. On averaged DWI, all 24 patients had hypointense signal in matching areas. IMH size derived using averaged‐DWI was nonsignificantly greater than from T2* (2.0 ± 1.0 cm2 vs 1.89 ± 0.96 cm2, P = 0.69). Compared to surrounding infarcted myocardium, MD was significantly reduced (1.29 ± 0.20 × 10−3 mm2/sec vs 1.75 ± 0.16 × 10−3 mm2/sec) and FA was significantly increased (0.40 ± 0.07 vs 0.23 ± 0.03) within areas of IMH. By V2, all 24 patients with acute IMH continued to have hypointense signals on averaged‐DWI in the affected area. T2* detected IMH in 96% of these patients. Overall, averaged‐DWI had 100% sensitivity and 96% specificity for the detection of IMH. Data Conclusion: This study demonstrates that the parameters MD and FA are susceptible to the paramagnetic properties of iron, enabling cDTI to detect IMH. Evidence Level: 1 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Background: The underlying pathophysiology of post-coronavirus disease 2019 (long-COVID-19) syndrome remains unknown, but increased cardiometabolic demand and state of mitochondrial dysfunction have emerged as candidate mechanisms. Cardiovascular magnetic resonance (CMR) provides insight into pathophysiological mechanisms underlying cardiovascular disease and 31-phosphorus CMR spectroscopy (31P-CMRS) allows non-invasive assessment of the myocardial energetic state. The main aim of the study was to assess whether long COVID-19 syndrome is associated with abnormalities of myocardial structure, function, perfusion and energy metabolism. Methods: Prospective case–control study. A total of 20 patients with a clinical diagnosis of long COVID-19 syndrome (seropositive) and no prior underlying cardiovascular disease (CVD) and 10 matching healthy controls underwent 31P-CMRS and CMR at 3T at a single time point. All patients had been symptomatic with acute COVID-19, but none required hospital admission. Results: Between the long COVID-19 syndrome patients and matched contemporary healthy controls there were no differences in myocardial energetics (phosphocreatine to ATP ratio), in cardiac structure (biventricular volumes), function (biventricular ejection fractions, global longitudinal strain), tissue characterization (T1 mapping and late gadolinium enhancement) or perfusion (myocardial rest and stress blood flow, myocardial perfusion reserve). One patient with long COVID-19 syndrome showed subepicardial hyperenhancement on late gadolinium enhancement imaging compatible with prior myocarditis, but no accompanying abnormality in cardiac size, function, perfusion, extracellular volume fraction, native T1, T2 or cardiac energetics. Conclusions: In this prospective case–control study, the overwhelming majority of patients with a clinical long COVID-19 syndrome with no prior CVD did not exhibit any abnormalities in myocardial energetics, structure, function, blood flow or tissue characteristics. [ABSTRACT FROM AUTHOR]

Background: Four‐dimensional (4D) flow cardiac magnetic resonance (cardiac MR) imaging provides quantification of intracavity left ventricular (LV) flow kinetic energy (KE) parameters in three dimensions. ST‐elevation myocardial infarction (STEMI) patients have been shown to have altered intracardiac blood flow compared to controls; however, how 4D flow parameters change over time has not been explored previously. Purpose: Measure longitudinal changes in intraventricular flow post‐STEMI and ascertain its predictive relevance of long‐term cardiac remodeling. Study Type: Prospective. Population: Thirty‐five STEMI patients (M:F = 26:9, aged 56 ± 9 years). Field Strength/Sequence: A 3 T/3D EPI‐based, fast field echo (FFE) free‐breathing 4D‐flow sequence with retrospective cardiac gating. Assessment: Serial imaging at 3–7 days (V1), 3‐months (V2), and 12‐months (V3) post‐STEMI, including the following protocol: functional imaging for measuring volumes and 4D‐flow for calculating parameters including systolic and peakE‐wave LVKE, normalized to end‐diastolic volume (iEDV) and stroke volume (iSV). Data were analyzed by H.B. (3 years experience). Patients were categorized into two groups: preserved ejection fraction (pEF, if EF > 50%) and reduced EF (rEF, if EF < 50%). Statistical Tests: Independent sample t‐tests were used to detect the statistical significance between any two cohorts. P < 0.05 was considered statistically significant. Results: Across the cohort, systolic KEisv was highest at V1 (28.0 ± 4.4 μJ/mL). Patients with rEF retained significantly higher systolic KEisv than patients with pEF at V2 (18.2 ± 3.4 μJ/mL vs. 6.9 ± 0.6 μJ/mL, P < 0.001) and V3 (21.6 ± 5.1 μJ/mL vs. 7.4 ± 0.9 μJ/mL, P < 0.001). Patients with pEF had significantly higher peakE‐wave KEiEDV than rEF patients throughout the study (V1: 25.4 ± 11.6 μJ/mL vs. 18.1 ± 9.9 μJ/mL, P < 0.03, V2: 24.0 ± 10.2 μJ/mL vs. 17.2 ± 12.2 μJ/mL, P < 0.05, V3: 27.7 ± 14.8 μJ/mL vs. 15.8 ± 7.6 μJ/mL, P < 0.04). Data Conclusion: Systolic KE increased acutely following MI; in patients with pEF, this decreased over 12 months, while patients with rEF, this remained raised. Compared to patients with pEF, persistently lower peakE‐wave KE in rEF patients is suggestive of early and fixed impairment in diastolic function. Evidence Level: 1 Technical Efficacy: Stage 3 [ABSTRACT FROM AUTHOR]

Background: Accurate evaluation of valvular pathology is crucial in the timing of surgical intervention. Whilst transthoracic echocardiography is widely available and routinely used in the assessment of valvular heart disease, it is bound by several limitations. Although cardiovascular magnetic resonance (CMR) imaging can overcome many of the challenges encountered by echocardiography, it also has a number of limitations. Main text: 4D Flow CMR is a novel technique, which allows time-resolved, 3-dimensional imaging. It enables visualisation and direct quantification of flow and peak velocities of all valves simultaneously in one simple acquisition, without any geometric assumptions. It also has the unique ability to measure advanced haemodynamic parameters such as turbulent kinetic energy, viscous energy loss rate and wall shear stress, which may add further diagnostic and prognostic information. Although 4D Flow CMR acquisition can take 5–10 min, emerging acceleration techniques can significantly reduce scan times, making 4D Flow CMR applicable in contemporary clinical practice. Conclusion: 4D Flow CMR is an emerging CMR technique, which has the potential to become the new reference-standard method for the evaluation of valvular lesions. In this review, we describe the clinical applications, advantages and disadvantages of 4D Flow CMR in the assessment of valvular heart disease. [ABSTRACT FROM AUTHOR]

Objective: Type 2 diabetes mellitus (T2DM) is associated with worsened clinical outcomes in hypertrophic cardiomyopathy (HCM) patients. We sought to investigate whether HCM patients with T2DM comorbidity exhibit adverse cardiac alterations in myocardial energetics, function, perfusion, or tissue characteristics.Research Design and Methods: A total of 55 participants with concomitant HCM and T2DM (HCM-DM) (n = 20) or isolated HCM (n = 20) and healthy volunteers (HV) (n = 15) underwent 31P-MRS and cardiovascular MRI. The HCM groups were matched for HCM phenotype.Results: Mean ± SD European Society of Cardiology sudden cardiac death risk scores were comparable between the HCM groups (HCM 2.2 ± 1.5%, HCM-DM 1.9 ± 1.2%; P = not significant), and sarcomeric mutations were equally common. HCM-DM patients had the highest median NT-proBNP levels (HV 42 ng/L [interquartile range 35-66], HCM 298 ng/L [157-837], HCM-DM 726 ng/L [213-8,695]; P < 0.0001). Left ventricular (LV) ejection fraction, mass, and wall thickness were similar between the HCM groups. HCM-DM patients displayed a greater degree of fibrosis burden with higher scar percentage and lower global longitudinal strain compared with HCM patients. PCr/ATP (the relative concentrations of phosphocreatine and ATP) was significantly lower in the HCM-DM group than in both HCM and HV (HV 2.17 ± 0.49, HCM 1.93 ± 0.38, HCM-DM 1.54 ± 0.27; P = 0.002). In a similar pattern, stress myocardial blood flow was significantly lower in the HCM-DM group than in both HCM and HV (HV 2.06 ± 0.42 mL/min/g, HCM 1.74 ± 0.44 mL/min/g, HCM-DM 1.39 ± 0.42 mL/min/g; P = 0.002).Conclusions: We show for the first time that HCM-DM patients display greater reductions in myocardial energetics, perfusion, and contractile function and higher myocardial scar burden and serum NT-proBNP levels compared with patients with isolated HCM despite similar LV mass and wall thickness and presence of sarcomeric mutations. These adverse phenotypic features may be important components of the adverse clinical manifestation attributable to a combined presence of HCM and T2DM. [ABSTRACT FROM AUTHOR]

The 25th Society for Cardiovascular Magnetic Resonance (SCMR) Annual Scientific Sessions saw 1524 registered participants from more than 50 countries attending the meeting virtually. Supporting the theme "CMR: Improving Cardiovascular Care Around the World", the meeting included 179 invited talks, 52 sessions including 3 plenary sessions, 2 keynote talks, and a total of 93 cases and 416 posters. The sessions were designed so as to showcase the multifaceted role of cardiovascular magnetic resonance (CMR) in identifying and prognosticating various myocardial pathologies. Additionally, various social networking sessions as well as fun activities were organized. The major areas of focus for the future are likely to be rapid efficient and high value CMR exams, automated and quantitative acquisition and post-processing using artificial intelligence and machine learning, multi-contrast imaging and advanced vascular imaging including 4D flow. [ABSTRACT FROM AUTHOR]

Aims Developments in myocardial perfusion cardiovascular magnetic resonance (CMR) allow improvements in spatial resolution and/or myocardial coverage. Whole heart coverage may provide the most accurate assessment of myocardial ischaemic burden, while high spatial resolution is expected to improve detection of subendocardial ischaemia. The objective of this study was to compare myocardial ischaemic burden as depicted by 2D high resolution and 3D whole heart stress myocardial perfusion in patients with coronary artery disease. Methods and results Thirty-eight patients [age 61 ± 8 (21% female)] underwent 2D high resolution (spatial resolution 1.2 mm2) and 3D whole heart (in-plane spatial resolution 2.3 mm2) stress CMR at 3-T in randomized order. Myocardial ischaemic burden (%) was visually quantified as perfusion defect at peak stress perfusion subtracted from subendocardial myocardial scar and expressed as a percentage of the myocardium. Median myocardial ischaemic burden was significantly higher with 2D high resolution compared with 3D whole heart [16.1 (2.0–30.6) vs. 13.4 (5.2–23.2), P  = 0.004]. There was excellent agreement between myocardial ischaemic burden (intraclass correlation coefficient 0.81; P  < 0.0001), with mean ratio difference between 2D high resolution vs. 3D whole heart 1.28 ± 0.67 (95% limits of agreement −0.03 to 2.59). When using a 10% threshold for a dichotomous result for presence or absence of significant ischaemia, there was moderate agreement between the methods (κ = 0.58, P  < 0.0001). Conclusion 2D high resolution and 3D whole heart myocardial perfusion stress CMR are comparable for detection of ischaemia. 2D high resolution gives higher values for myocardial ischaemic burden compared with 3D whole heart, suggesting that 2D high resolution is more sensitive for detection of ischaemia. [ABSTRACT FROM AUTHOR]

This position statement guides cardiovascular magnetic resonance (CMR) imaging program directors and learners on the key competencies required for Level II and III CMR practitioners, whether trainees come from a radiology or cardiology background. This document is built upon existing curricula and was created and vetted by an international panel of cardiologists and radiologists on behalf of the Society for Cardiovascular Magnetic Resonance (SCMR). [Display omitted] [ABSTRACT FROM AUTHOR]