Evaluation of cardiac remodeling in pediatric chronic kidney disease by cardiovascular magnetic resonance.

BACKGROUND: Children with chronic kidney disease (CKD) are at high risk of cardiovascular disease. Cardiovascular magnetic resonance (CMR) is the reference method for assessing cardiac remodeling. To our knowledge, no study has reported a comprehensive analysis of left ventricular(LV) cardiac remodeling using CMR in different stages of pediatric CKD. This prospective case-control study aimed to investigate cardiac remodeling in pediatric CKD, using CMR, and determine its relationship with risk factors. METHOD: CMR was performed in 124 children with CKD and 50 controls. The cardiac remodeling parameters included left ventricular mass index (LVMI), LV remodeling index (LVRI), and LV wall thickness. Univariable and multivariable analyses were performed to assess the cardiac remodeling risk factors. RESULTS: Cardiac remodeling was observed in 35.5% (44/124) of children with CKD. The LVMI, LVRI, and LV wall thickness were higher in advanced stages of CKD (P < 0.05). In the CKD stage 1-2 group, a lower in the estimated glomerular filtration rate was an independent determinant of impaired LVMI (ß = -0.425, P = 0.019) and LVRI (ß = -0.319, P = 0.044). A higher protein to creatinine ratio(PCR) was independently associated with impaired LVRI (ß = 0.429, P = 0.022). In the CKD stage 3-5 group, higher in systolic blood pressure (SBP) (ß = 0.464, P = 0.005) and PCR (ß = 0.852, P = 0.031) were independent determinants of impaired LVMI. Additionally, higher SBP was positively correlated with impaired LVRI(r = 0.599, P < 0.001). There was a trend toward more abnormal cardiac remodeling in the CKD stage 3-5 group with hypertension than those without. CONCLUSION: Cardiac remodeling is prevalent in children with CKD, from an early stage. kidney markers are independently associated with cardiac remodeling. Hypertension increases the risk of cardiac remodeling in CKD stages 3-5. Strict BP control may help reverse or prevent remodeling.

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

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

Prognostic Implications of Clinical and Imaging Diagnostic Criteria for Myocarditis.

BACKGROUND: The European Society of Cardiology (ESC), the American College of Cardiology, the American Heart Association, and expert consensus documents provide different diagnostic criteria for myocarditis. Their overlap and prognostic value have never been compared. OBJECTIVES: This study aims to assess and compare the predictive value of ESC criteria for clinically suspected myocarditis, updated Lake-Louise criteria (LLC), American Heart Association criteria for probable acute myocarditis (pAM), and expert consensus criteria for acute myocarditis (AM) and complicated myocarditis (CM). METHODS: Patients with a clinical suspicion of myocarditis referred for cardiac magnetic resonance were enrolled at 2 centers. Those with any prior cardiomyopathy were excluded. The association of composite outcome events (heart failure hospitalization, recurrent myocarditis, sustained ventricular tachycardia, or death) with ESC diagnostic criteria, LLC, pAM, AM, and CM were compared. RESULTS: Among 1,557 consecutive patients referred for cardiac magnetic resonance with possible myocarditis, 1,050 (62.6% male; 48.9 ± 16.8 years of age) were without an alternative diagnosis. Of those, 938 (89.3%) met ESC criteria for clinically suspected myocarditis, 299 (28.5%) LLC, and 356 (33.9%), 216 (20.6%), and 77 (7.3%) pAM, AM, and CM, respectively. Adverse events occurred in 161 patients (15.3%) during a median follow-up of 3.4 years. The highest annualized event rates (6.6%) were observed in patients meeting LLC, whereas negative ESC criteria indicated excellent prognosis (0.7% annualized event rate). Among all myocarditis definitions, ESC criteria and LLC were the strongest multivariable outcome predictors and had independent and incremental prognostic value (HRadjusted: 3.87; 95% CI: 1.22-12.2; P = 0.021, and HRadjusted: 2.53; 95% CI: 1.83-3.49; P < 0.001, respectively) when adjusted for clinical characteristics. CONCLUSIONS: In a real-world cohort of patients with possible myocarditis, diagnosis was reached in most patients using ESC criteria whereas only approximately one-quarter of patients reached a diagnosis with LLC. The independent prognostic value of ESC-criteria and LLC highlights the complementary role of clinical and CMR-based findings in the diagnosis and risk stratification of myocarditis.

Arrhythmic Risk Stratification by Cardiovascular Magnetic Resonance Imaging in Patients With Nonischemic Cardiomyopathy.

BACKGROUND: Myocardial fibrosis (MF) forms part of the arrhythmic substrate for ventricular arrhythmias (VAs). OBJECTIVES: This study sought to determine whether total myocardial fibrosis (TF) and gray zone fibrosis (GZF), assessed using cardiovascular magnetic resonance, are better than left ventricular ejection fraction (LVEF) in predicting ventricular arrhythmias in patients with nonischemic cardiomyopathy (NICM). METHODS: Patients with NICM in a derivation cohort (n = 866) and a validation cohort (n = 848) underwent quantification of TF and GZF. The primary composite endpoint was sudden cardiac death or VAs (ventricular fibrillation or ventricular tachycardia). RESULTS: The primary endpoint was met by 52 of 866 (6.0%) patients in the derivation cohort (median follow-up: 7.5 years; Q1-Q3: 5.2-9.3 years). In competing-risks analyses, MF on visual assessment (MFVA) predicted the primary endpoint (HR: 5.83; 95% CI: 3.15-10.8). Quantified MF measures permitted categorization into 3 risk groups: a TF of >0 g and ≤10 g was associated with an intermediate risk (HR: 4.03; 95% CI: 1.99-8.16), and a TF of >10 g was associated with the highest risk (HR: 9.17; 95% CI: 4.64-18.1) compared to patients with no MFVA (lowest risk). Similar trends were observed in the validation cohort. Categorization into these 3 risk groups was achievable using TF or GZF in combination or in isolation. In contrast, LVEF of <35% was a poor predictor of the primary endpoint (validation cohort HR: 1.99; 95% CI: 0.99-4.01). CONCLUSIONS: MFVA is a strong predictor of sudden cardiac death and VAs in NICM. TF and GZF mass added incremental value to MFVA. In contrast, LVEF was a poor discriminator of arrhythmic risk.

Predicting Late Gadolinium Enhancement of Acute Myocardial Infarction in Contrast-Free Cardiac Cine MRI Using Deep Generative Learning.

BACKGROUND: Late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) is a standard technique for diagnosing myocardial infarction (MI), which, however, poses risks due to gadolinium contrast usage. Techniques enabling MI assessment based on contrast-free CMR are desirable to overcome the limitations associated with contrast enhancement. METHODS: We introduce a novel deep generative learning method, termed cine-generated enhancement (CGE), which transforms standard contrast-free cine CMR into LGE-equivalent images for MI assessment. CGE features with multislice spatiotemporal feature extractor, enhancement contrast modulation, and sophisticated loss function. Data from 430 patients with acute MI from 3 centers were collected. After image quality control, 1525 pairs (289 patients) of center I were used for training, and 293 slices (52 patients) of the same center were reserved for internal testing. The 40 patients (401 slices) of the other 2 centers were used for external testing. The CGE robustness was further tested in 20 normal subjects in a public cine CMR data set. CGE images were compared with LGE for image quality assessment and MI quantification regarding scar size and transmurality. RESULTS: The CGE method produced images of superior quality to LGE in both internal and external data sets. There was a significant (P<0.001) correlation between CGE and LGE measurements of scar size (Pearson correlation, 0.79/0.80; intraclass correlation coefficient, 0.79/0.77) and transmurality (Pearson correlation, 0.76/0.64; intraclass correlation coefficient, 0.76/0.63) in internal/external data set. Considering all data sets, CGE demonstrated high sensitivity (91.27%) and specificity (95.83%) in detecting scars. Realistic enhancement images were obtained for the normal subjects in the public data set without false positive subjects. CONCLUSIONS: CGE achieved superior image quality to LGE and accurate scar delineation in patients with acute MI of both internal and external data sets. CGE can significantly simplify the CMR examination, reducing scan times and risks associated with gadolinium-based contrasts, which are crucial for acute patients.

Cardiac magnetic resonance imaging-derived pathophysiology and prognosis of diabetes mellitus with acute myocardial infarction after revascularization: a prospective cohort study.

BACKGROUND: Little is known about the underlying factors contributing to unfavourable clinical outcomes in patients with diabetes mellitus (DM) complicated by new-onset acute myocardial infarction (AMI). The aim of this study was to investigate the impact of DM on the pathophysiologic features and prognosis of patients with new-onset AMI following successful revascularization by utilizing cardiac magnetic resonance (CMR). METHODS: Consecutive patients diagnosed with new-onset AMI between June 2022 and January 2024 were included. All patients underwent culprit vessel revascularization upon admission and CMR imaging 3-7 days later. The primary clinical endpoint of this study was the occurrence of major adverse cardiac and cerebrovascular events (MACCEs), for which the average follow-up was 10 months. RESULTS: A total of 72 patients were divided into a DM group (n = 23) and a non-DM group (n = 49). Multivariate logistic regression analysis revealed that DM was an independent risk factor for the occurrence of microvascular obstruction. Multivariate linear regression analysis found that DM was the influencing factor of global radial strain (B = -4.107, t = -2.328, p = 0.023), while fasting blood glucose influenced infarct segment myocardial radial strain (B = -0.622, t = -2.032, p = 0.046). DM independently contributed to the risk of MACCEs following successful revascularization in patients with AMI (p < 0.05). CONCLUSION: Comprehensive phenotypic characterization of myocardial injury and microcirculatory status could enable reliable identification of high-risk MACCEs in DM patients with new-onset AMI following successful revascularization.

New atrio-ventricular indices derived from conventional cine MRI correlate with functional capacity in patients with asymptomatic primary mitral regurgitation.

Mitral regurgitation (MR) is associated with morphological and functional alterations of left atrium (LA) and ventricle (LV), possibly inducing LA-LV misalignment. We aimed to: (1) characterize angulation between LA and mitral annulus from conventional cine MRI data and feature-tracking (FT) contours, (2) assess their associations with functional capacity in MR patients, as assessed by oxygen consumption (peak-VO2) and minute ventilation to carbon dioxide production (VE/VCO2) slope, in comparison with MRI LA/LV strain indices. Thirty-two asymptomatic primary MR patients (56 [40; 66] years, 12 women) underwent cardiac MRI resulting in LA/LV conventional FT-derived strain indices. Then, end-diastolic angles were derived from FT LA contours: (1) α, centered on the LA centre of mass and defined by mitral valve extremities, (2) γ, centered on the mitral ring anterior/lateral side, and defined by LA centre and the other extremity of the mitral ring. Cardiopulmonary exercise testing with simultaneous echocardiography were also performed; peak-VO2 and VE/VCO2 slope were measured. While peak-VO2 and VE/VCO2 slope were not correlated to LA/LV strains, they were significantly associated with angles (α: r = 0.50, p = 0.003 and r = - 0.52, p = 0.003; γ: r = - 0.53, p = 0.002 and r = 0.52, p = 0.003; respectively), independently of age and gender (R2 ≥ 0.29, p ≤ 0.03). In primary MR, the new LA/mitral annulus angles, computed directly from standard-of-care MRI, are better correlated to exercise tolerance than conventional LA/LV strain.

The differential effects of dyslipidemia status and triglyceride-glucose index on left ventricular global function and myocardial microcirculation in diabetic individuals: a cardiac magnetic resonance study.

BACKGROUND: It remains unclear whether the association between dyslipidemia status and triglyceride-glucose (TyG) index with myocardial damage varies in the context of type 2 diabetes mellitus (T2DM). This study aimed to determine the differential effects of dyslipidemia status and TyG index on left ventricular (LV) global function and myocardial microcirculation in patients with T2DM using cardiac magnetic resonance (CMR) imaging. METHODS: A total of 226 T2DM patients and 72 controls who underwent CMR examination were included. The T2DM group was further categorized into subgroups based on the presence or absence of dyslipidemia (referred to as T2DM (DysL+) and T2DM (DysL-)) or whether the TyG index exceeded 9.06. CMR-derived LV perfusion parameters, remodeling index, and global function index (GFI) were assessed and compared among groups. A multivariable linear regression model was employed to evaluate the effects of various variables on LV myocardial microcirculation, remodeling index, and GFI. RESULTS: The LV GFI sequentially decreased in controls, T2DM (DysL-), and T2DM (DysL+) groups (p < 0.001), and was lower (p = 0.003) in T2DM with higher TyG index group than in lower TyG index group. The LV remodeling index was higher in higher TyG index group than in lower TyG index group (p = 0.002), but there was no significant difference in whether the subgroup was accompanied by dyslipidemia. Multivariable analysis revealed that the TyG index, but not dyslipidemia status, was independently associated with LV remodeling index (ß coefficient[95% confidence interval], 0.152[0.025, 0.268], p = 0.007) and LV GFI (- 0.159[- 0.281, - 0.032], p = 0.014). For LV myocardial microcirculation, perfusion index, upslope, and max signal intensity sequentially decreased in controls, T2DM (DysL-), and T2DM (DysL+) groups (all p < 0.001). Dyslipidemia status independently correlated with perfusion index (- 0.147[- 0.272, - 0.024], p = 0.02) and upslope (- 0.200[- 0.320, 0.083], p = 0.001), while TyG index was independently correlated with time to maximum signal intensity (0.141[0.019, 0.257], p = 0.023). CONCLUSIONS: Both dyslipidemia status and higher TyG index were associated with further deterioration of LV global function and myocardial microvascular function in the context of T2DM. The effects of dyslipidemia and a higher TyG index appear to be differential, which indicates that not only the amount of blood lipids and glucose but also the quality of blood lipids are therapeutic targets for preventing further myocardial damage.

Deep Learning Virtual Contrast-Enhanced T1 Mapping for Contrast-Free Myocardial Extracellular Volume Assessment.

BACKGROUND: The acquisition of contrast-enhanced T1 maps to calculate extracellular volume (ECV) requires contrast agent administration and is time consuming. This study investigates generative adversarial networks for contrast-free, virtual extracellular volume (vECV) by generating virtual contrast-enhanced T1 maps. METHODS AND RESULTS: This retrospective study includes 2518 registered native and contrast-enhanced T1 maps from 1000 patients who underwent cardiovascular magnetic resonance at 1.5 Tesla. Recent hematocrit values of 123 patients (hold-out test) and 96 patients from a different institution (external evaluation) allowed for calculation of conventional ECV. A generative adversarial network was trained to generate virtual contrast-enhanced T1 maps from native T1 maps for vECV creation. Mean and SD of the difference per patient (ΔECV) were calculated and compared by permutation of the 2-sided t test with 10 000 resamples. For ECV and vECV, differences in area under the receiver operating characteristic curve (AUC) for discriminating hold-out test patients with normal cardiovascular magnetic resonance versus myocarditis or amyloidosis were tested with Delong's test. ECV and vECV showed a high agreement in patients with myocarditis (ΔECV: hold-out test, 2.0%±1.5%; external evaluation, 1.9%±1.7%) and normal cardiovascular magnetic resonance (ΔECV: hold-out test, 1.9%±1.4%; external evaluation, 1.5%±1.2%), but variations in amyloidosis were higher (ΔECV: hold-out test, 6.2%±6.0%; external evaluation, 15.5%±6.4%). In the hold-out test, ECV and vECV had a comparable AUC for the diagnosis of myocarditis (ECV AUC, 0.77 versus vECV AUC, 0.76; P=0.76) and amyloidosis (ECV AUC, 0.99 versus vECV AUC, 0.96; P=0.52). CONCLUSIONS: Generation of vECV on the basis of native T1 maps is feasible. Multicenter training data are required to further enhance generalizability of vECV in amyloidosis.

Increased Aortic Stiffness With Acute Exercise in Heart Failure: Assessment by Cardiovascular Magnetic Resonance.

This study aimed to investigate the acute changes in proximal aortic distensibility, a measure of aortic stiffness, induced by acute exercise in participants with and without heart failure (HF). Participants with HF (n = 24) and without HF (n = 26) underwent cardiovascular magnetic resonance (CMR) (1.5 T) imaging at rest and after submaximal supine bicycle ergometry. The participants were further categorized into HF with reduced ejection fraction (HFrEF) (n = 14) and HF with preserved ejection fraction (n = 10) based on the left ventricular ejection fraction. At rest and immediately after exercise, cine CMR images of the cross-sectional ascending and descending aorta at the pulmonary artery bifurcation level were obtained to determine aortic distensibility (AoD), with lower AoD indicating greater aortic stiffness. Differences in means of values at rest and before and after exercise were compared using the nonparametric Wilcoxon sign test. There was no significant difference in AoD at rest between subjects with HF and controls. However, immediately after exercise, participants with HF but not controls exhibited a significant reduction in AoD, indicating higher aortic stiffness related to exercise (median [interquartile range] for the ascending aorta: 3.16 (1.26) × 10-3 mm Hg-1 to 2.39 (1.57) × 10-3 mm Hg-1 and the descending aorta: 4.19 (2.58) × 10-3 mm Hg-1 to 2.96 (1.79) × 10-3 mm Hg-1) (both p = 0.023). This decrease was particularly observed in participants with HFrEF but not in those with HF with preserved ejection fraction. Exercise-induced aortic stiffness, detectable by noninvasive CMR, may contribute to unfavorable ventricular-vascular interactions during exercise in participants with HF, especially HFrEF.

Impact of epicardial fat on coronary vascular function, cardiac morphology, and cardiac function in women with suspected INOCA.

AIMS: Epicardial fat is a metabolically active adipose tissue depot situated between the myocardium and visceral pericardium that covers ∼80% of the heart surface. While epicardial fat has been associated with the development of atherosclerotic coronary artery disease, less is known about the relationship between epicardial fat and coronary vascular function. Moreover, the relations between excess epicardial fat and cardiac morphology and function remain incompletely understood. METHODS AND RESULTS: To address these knowledge gaps, we retrospectively analysed data from 294 individuals from our database of women with suspected ischaemia with no obstructive coronary disease (INOCA) who underwent both invasive coronary function testing and cardiac magnetic resonance imaging. Epicardial fat area, biventricular morphology, and function, as well as left atrial function, were assessed from cine images, per established protocols. The major novel findings were two-fold: first, epicardial fat area was not associated with coronary vascular dysfunction. Secondly, epicardial fat was associated with increased left ventricular concentricity (ß = 0.15, P = 0.01), increased septal thickness (ß = 0.17, P = 0.002), and reduced left atrial conduit fraction (ß = -0.15, P = 0.02), even after accounting for age, BMI, and history of hypertension. CONCLUSION: Taken together, these data do not support a measurable relationship between epicardial fat and coronary vascular dysfunction but do suggest that epicardial fat may be related to concentric remodelling and diastolic dysfunction in women with suspected INOCA. Prospective studies are needed to elucidate the long-term impact of epicardial fat in this patient population.

Prognostic value of electroanatomic-guided endomyocardial biopsy in patients with myocarditis, arrhythmogenic cardiomyopathy and non dilated left ventricular cardiomyopathy.

A wide variety of non-invasive and invasive techniques for SCD risk stratification in non ischemic cardiomyopathy (NICM) have been proposed, including left ventricular (LV) ejection fraction, QRS duration, late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) and invasive electrophysiologic study with or without three-dimensional electroanatomic mapping (3D-EAM), to identify and characterize the arrhythmogenic substrate. There is still no clear consensus on the risk stratification in this clinical setting. The aim of our study is to characterize the 3D-EAM substrate in patients with the same clinical presentation of unexplained complex VAs and NICM using CMR, three-dimensional electranatomic mapping (3D-EAM) in association with endomyocardial biopsy (EMB) and genetic screening, as a more precise and early diagnostic assessment may provide important subsequent prognostic impact. The study was designed as a prospective multi-center observational evaluation and the patient follow-up was scheduled at 6 months interval. We enrolled 125 patients distinct into four different group by complete diagnostic work-up: myocarditis, non-dilated left ventricular cardiomyopathy, arrhythmogenic cardiomyopathy and control group. The four groups were compared in terms of clinical, imaging and 3D-EAM data. At multivariate analysis sustained VT/VF on admission [HR: 3.64 (1.79-7.4), p < 0.001], total bipolar scar area of left and right ventricle detected by 3D-EAM [HR: 2.24 (1.13-4.49), p = 0.02], histological diagnosis of myocarditis by 3D-EAM guided endomyocardial biopsy (EBM) [HR: 2.79 (1.04-7.44), p = 0.01] were independent predictors of complex VAs or death at follow-up. 3D-EAM guided EMB represent not only a valid diagnostic tool to identify the arrhythmogenic substrate in patients with NICM and ventricular arrhythmic phenotype but also an important predictor of complex Vas at long term follow-up.

Association of Circulating PCSK9 With Ischemia-Reperfusion Injury in Acute ST-Elevation Myocardial Infarction.

BACKGROUND: Beyond therapeutic implications, PCSK9 (proprotein convertase subtilisin/kexin 9) has emerged as a promising cardiovascular biomarker. The exact role of PCSK9 in the setting of acute ST-elevation myocardial infarction (STEMI) is incompletely understood. We aimed to investigate the association of PCSK9 with ischemia-reperfusion injury, visualized by cardiac magnetic resonance imaging, in patients with STEMI revascularized by primary percutaneous coronary intervention (PCI). METHODS: In this prespecified substudy from the prospective MARINA-STEMI (NCT04113356) registry, we included 205 patients with STEMI. PCSK9 concentrations were measured from venous blood samples by an immunoassay 24 and 48 hours after PCI. The primary end point was defined as presence of intramyocardial hemorrhage according to cardiac magnetic resonance T2* mapping. Secondary imaging end points were the presence of microvascular obstruction (MVO) and infarct size. The clinical end point was the occurrence of major adverse cardiac events. RESULTS: We observed a significant increase in PCSK9 levels from 24 to 48 hours (268-304 ng/mL; P<0.001) after PCI. PCSK9 24 hours after PCI did not show any relation to intramyocardial hemorrhage, MVO, and infarct size (all P>0.05). PCSK9 concentrations 48 hours post-STEMI were higher in patients with intramyocardial hemorrhage (333 versus 287 ng/mL; P=0.004), MVO (320 versus 292 ng/mL; P=0.020), and large infarct size (323 versus 296 ng/mL; P=0.013). Furthermore, patients with increased PCSK9 levels >361 ng/mL at 48 hours were more likely to experience major adverse cardiac events (15% versus 8%; P=0.002) during a median follow-up of 12 months. CONCLUSIONS: In patients with STEMI, a significant increase in PCSK9 was observed from 24 to 48 hours after PCI. While PCSK9 levels after 24 hours were not related to myocardial or microvascular injury, PCSK9 after 48 hours was significantly associated with intramyocardial hemorrhage, MVO, and infarct size as well as worse subsequent clinical outcomes. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier; NCT04113356.

Measurements of the Interventricular Septum and Mitral Leaflet Length in Hypertrophic Cardiomyopathy Patients Who Underwent Surgical Myectomy: A Prospective Comparative Multimodality Imaging Study.

Transesophageal echocardiography (TEE) plays an important role for real-time procedural guidance during surgical smyectomy (SM) for hypertrophic obstructive cardiomyopathy (HOCM). We aimed to compare (1) interventricular septum (IVS) thickness using 2- (2D) and 3-dimensional (3D) intraoperative TEE and preoperative cardiac magnetic resonance (CMR) and (2) mitral valve (MV) leaflet length using 2D, 3D TEE, automatic quantification of mitral valve (AMVQ) and preoperative CMR. We prospectively studied 50 patients with HOCM (age 59 ± 12 years, 44% men) who underwent SM during 2018 to 2019. The maximal basal, mid, and distal anteroseptum (AS) and inferoseptum (IS) were measured by multiplanar 3D reconstruction on TEE and by short-axis imaging on preoperative CMR and classified as mild (≤18 mm), moderate (18 to 25 mm), or severe (≥25 mm) groups based on AS and IS thickness on CMR. MV leaflet lengths were evaluated by preoperative CMR and intraprocedural 2D TEE, zoom 3D TEE, and AMVQ (EchoPAC, General Electric, Wisconsin). There was a moderate correlation between AS and IS thickness on 3D TEE and CMR (R2 = 0.46, p <0.01 and R2 = 0.41, p <0.01, respectively), with 3D TEE showing an average overestimation of 3.8 and 4.7 mm versus CMR. The 3D TEE overestimated 14 patients (56%) with mild thickness as moderate and 5 patients (22%) with moderate thickness as severe. Assuming 3D TEE as the gold standard, the closest correlation for anterior mitral leaflet length was with CMR (average overestimation by CMR of 0.5 mm [root mean square deviation (RMSE%) 17]), intermediate correlation with 2D TEE (average deviation of 0.6 mm [RMSE% 21]) and no correlation with AMVQ (average deviation of 0.7 mm [RMSE% 24]). In conclusion, 3D TEE overestimates IVS thickness versus CMR in patients with HOCM who underwent SM, with greater discrepancy in those with thinner IVS. There are significant differences in MV lengths measured using different imaging techniques.

Cardiac Magnetic Resonance Left Atrial Strain in the Prediction of Death, Ischemic Stroke, and Heart Failure.

BACKGROUND: To determine the prognostic value of left atrial strain (LAS) using cardiac magnetic resonance for predicting death, heart failure, and ischemic stroke in patients with known or suspected coronary artery disease with preserved left ventricular systolic function and no prior history of ischemic stroke, heart failure, or atrial fibrillation. METHODS AND RESULTS: This retrospective cohort analysis included patients referred for stress cardiac magnetic resonance or myocardial viability studies between September 2017 and December 2019. Patients with impaired left ventricular systolic function (<50%) or a history of atrial fibrillation, stroke, or heart failure were excluded. A multivariable Cox model assessed the prognostic value of LAS, with the primary outcomes being the composite outcomes of all-cause death, ischemic stroke, and heart failure. A total of 2030 participants were included in the study. The average LAS was 24.1±8.5%; 928 had LAS <23%, and 1102 had LAS ≥23%. The mean follow-up duration was 39.9±13.6 months. There were 49 deaths (2.4%), 32 ischemic strokes (1.6%), and 34 heart failure events (1.7%). Patients with LAS <23% were at greater risk for composite outcome, with an adjusted hazard ratio of 2.31 (95% CI, 1.50-3.55). CONCLUSIONS: LAS by cardiac magnetic resonance has an independent and incremental prognostic value for death, ischemic stroke, and heart failure in patients with preserved left ventricular systolic function. This prognostic value is observed after adjusting for clinical and cardiac magnetic resonance parameters, including left ventricular systolic function, late gadolinium enhancement, and left atrial volume index.

Assessment of Left Atrial Fibrosis by Cardiac Magnetic Resonance Imaging in Ischemic Stroke Patients Without Atrial Fibrillation: A Systematic Review and Meta-Analysis.

BACKGROUND: Left atrial (LA) fibrosis is a marker of atrial cardiomyopathy and has been reported to be associated with both atrial fibrillation and ischemic stroke. Elucidating this relationship is clinically important as LA fibrosis could serve as a surrogate biomarker of LA cardiomyopathy. The objective of this study is to investigate the association of LA fibrosis and embolic stroke of undetermined source (ESUS) using cardiac magnetic resonance imaging. METHODS AND RESULTS: Following an International Prospective Register of Systematic Reviews-registered protocol, 3 blinded reviewers performed a systematic review for studies that quantified the degree of LA fibrosis in patients with ESUS as compared with healthy patients from inception to February 2024. A meta-analysis was conducted in the mean difference. From 7 studies (705 patients), there was a significantly higher degree of LA fibrosis in patients with ESUS compared with healthy controls (MD, 5.71% [95% CI, 3.55%-7.87%], P<0.01). The degree of LA fibrosis was significantly higher in patients with atrial fibrillation than healthy controls (MD, 8.22% [95% CI, 5.62%-10.83%], P<0.01). A similar degree of LA fibrosis was observed in patients with ESUS compared with patients with atrial fibrillation (MD, -0.92% [95% CI, -2.29% to 0.44%], P=0.35). CONCLUSIONS: A significantly higher degree of LA fibrosis was found in patients with ESUS as compared with healthy controls. This suggests that LA fibrosis may play a significant role in the pathogenesis of ESUS. Further research is warranted to investigate LA fibrosis as a surrogate biomarker of atrial cardiomyopathy and recurrent stroke risk in patients with ESUS.

Association of Cardiac MRI-derived Aortic Stiffness with Early Stages and Progression of Heart Failure with Preserved Ejection Fraction.

Purpose To investigate if aortic stiffening as detected with cardiac MRI is an early phenomenon in the development and progression of heart failure with preserved ejection fraction (HFpEF). Materials and Methods Both clinical and preclinical studies were performed. The clinical study was a secondary analysis of the prospective HFpEF stress trial (August 2017 through September 2019) and included 48 participants (median age, 69 years [range, 65-73 years]; 33 female, 15 male) with noncardiac dyspnea (NCD, n = 21), overt HFpEF at rest (pulmonary capillary wedge pressure [PCWP] ≥ 15 mm Hg, n = 14), and masked HFpEF at rest diagnosed during exercise stress (PCWP ≥ 25 mm Hg, n = 13) according to right heart catheterization. Additionally, all participants underwent echocardiography and cardiac MRI at rest and during exercise stress. Aortic pulse wave velocity (PWV) was calculated. The mechanistic preclinical study characterized cardiac function and structure in transgenic mice with induced arterial stiffness (Runx2-smTg mice). Statistical analyses comprised nonparametric and parametric comparisons, Spearman correlations, and logistic regression models. Results Participants with HFpEF showed increased PWV (NCD vs masked HFpEF: 7.0 m/sec [IQR: 5.0-9.5 m/sec] vs 10.0 m/sec [IQR: 8.0-13.4 m/sec], P = .005; NCD vs overt HFpEF: 7.0 m/sec [IQR: 5.0-9.5 m/sec] vs 11.0 m/sec [IQR: 7.5-12.0 m/sec], P = .01). Increased PWV correlated with higher PCWP (P = .006), left atrial and left ventricular long-axis strain (all P < .02), and N-terminal pro-brain natriuretic peptide levels (P < .001). Participants with overt HFpEF had higher levels of myocardial fibrosis, as demonstrated by increased native T1 times (1199 msec [IQR: 1169-1228 msec] vs 1234 msec [IQR: 1208-1255 msec], P = .009). Aortic stiffness was independently associated with HFpEF on multivariable analyses (odds ratio, 1.31; P = .049). Runx2-smTG mice exhibited an "HFpEF" phenotype compared with wild-type controls, with preserved left ventricular fractional shortening but an early and late diastolic mitral annulus velocity less than 1 (mean, 0.67 ± 0.39 [standard error of the mean] vs 1.45 ± 0.47; P = .004), increased myocardial collagen deposition (mean, 11% ± 1 vs 2% ± 1; P < .001), and increased brain natriuretic peptide levels (mean, 171 pg/mL ± 23 vs 101 pg/mL ± 10; P < .001). Conclusion This study provides translational evidence that increased arterial stiffness might be associated with development and progression of HFpEF and may facilitate its early detection. Keywords: MR Functional Imaging, MR Imaging, Animal Studies, Cardiac, Aorta, Heart ClinicalTrials.gov identifier NCT03260621 Supplemental material is available for this article. © RSNA, 2024.

What happened to the left ventricular non-compaction cardiomyopathy? to be or not to be: This is the question.

For several years, left ventricular non-compaction (LVNC) was considered as a true cardiomyopathy and several definitions have followed one another. Particularly, LVNC was characterized by prominent left ventricular trabeculae separated from deep intertrabecular recesses. Several echocardiographic criteria and cardiac magnetic resonance imaging (CMR) criteria have been used to diagnose LVNC, leading to overestimate the diagnosis of LVNC in patients with other diseases and/or physiological conditions. Left ventricular hypertrabeculation (LVH) can be present in several cardiac diseases and physiological conditions: heart failure with reduced ejection fraction, thalassemia and other hematological diseases, pregnancy, athlete's heart. Thus, the presence of LVH does not necessarily indicate the presence of an LVNC. In addition, the great heterogeneity of clinical manifestations has raised concerns regarding the existence of a true LVNC as a cardiomyopathy. In fact, LVNC ranges from genetic to acquired and even transient conditions, isolated forms or forms associated with other cardiomyopathies, congenital heart diseases or syndromes with a very different prognosis. Thus, considering LVH as a manifestation of various diseases and physiological conditions, the recent 2023 ESC guidelines on cardiomyopathies did not include LVNC among cardiomyopathies, but they suggested using the term "LVH" rather than LVNC, to describe this phenotype especially when it is transient or of adult-onset. In this review, we aimed to make an excursion on LVNC, from its initial description to the present day, to understand why current guidelines decided to consider LVH as a phenotypic trait rather than a distinct cardiomyopathy.