Diabetes mellitus and insulin resistance associate with left ventricular shape and torsion by cardiovascular magnetic resonance imaging in asymptomatic individuals from the multi-ethnic study of atherosclerosis

Myocardial transcriptomic analysis of diabetic patients with aortic stenosis: key role for mitochondrial calcium signaling

BACKGROUND

Type 2 diabetes (T2D) is a frequent comorbidity encountered in patients with severe aortic stenosis (AS), leading to an adverse left ventricular (LV) remodeling and dysfunction. Metabolic alterations have been suggested as contributors of the deleterious effect of T2D on LV remodeling and function in patients with severe AS, but so far, the underlying mechanisms remain unclear. Mitochondria play a central role in the regulation of cardiac energy metabolism.

OBJECTIVES

We aimed to explore the mitochondrial alterations associated with the deleterious effect of T2D on LV remodeling and function in patients with AS, preserved ejection fraction, and no additional heart disease.

METHODS

We combined an in-depth clinical, biological and echocardiography phenotype of patients with severe AS, with (n = 34) or without (n = 50) T2D, referred for a valve replacement, with transcriptomic and histological analyses of an intra-operative myocardial LV biopsy.

RESULTS

T2D patients had similar AS severity but displayed worse cardiac remodeling, systolic and diastolic function than non-diabetics. RNAseq analysis identified 1029 significantly differentially expressed genes. Functional enrichment analysis revealed several T2D-specific upregulated pathways despite comorbidity adjustment, gathering regulation of inflammation, extracellular matrix organization, endothelial function/angiogenesis, and adaptation to cardiac hypertrophy. Downregulated gene sets independently associated with T2D were related to mitochondrial respiratory chain organization/function and mitochondrial organization. Generation of causal networks suggested a reduced Ca2+ signaling up to the mitochondria, with the measured gene remodeling of the mitochondrial Ca2+ uniporter in favor of enhanced uptake. Histological analyses supported a greater cardiomyocyte hypertrophy and a decreased proximity between the mitochondrial VDAC porin and the reticular IP3-receptor in T2D.

CONCLUSIONS

Our data support a crucial role for mitochondrial Ca2+ signaling in T2D-induced cardiac dysfunction in severe AS patients, from a structural reticulum-mitochondria Ca2+ uncoupling to a mitochondrial gene remodeling. Thus, our findings open a new therapeutic avenue to be tested in animal models and further human cardiac biopsies in order to propose new treatments for T2D patients suffering from AS.

TRIAL REGISTRATION

URL: https://www.

CLINICALTRIALS

gov ; Unique Identifier: NCT01862237.

Effects of diabetes mellitus on left ventricular function and deformation in patients with restrictive cardiomyopathies: a 3.0T CMR feature tracking study

BACKGROUND

Diabetes mellitus (DM) is the most common metabolic disease worldwide and a major risk factor for adverse cardiovascular events, while the additive effects of DM on left ventricular (LV) deformation in the restrictive cardiomyopathy (RCM) cohort remain unclear. Accordingly, we aimed to investigate the additive effects of DM on LV deformation in patients with RCM.

MATERIALS AND METHODS

One hundred thirty-six RCM patients without DM [RCM(DM-)], 46 with DM [RCM (DM+)], and 66 age- and sex-matched control subjects who underwent cardiac magnetic resonance (CMR) scanning were included. LV function, late gadolinium enhancement (LGE) type, and LV global peak strains (including radial, circumferential, and longitudinal directions) were measured. The determinant of reduced LV global myocardial strain for all RCM patients was assessed using multivariable linear regression analyses. The receiver operating characteristic curve (ROC) was performed to illustrate the relationship between DM and decreased LV deformation.

RESULTS

Compared with the control group, RCM (DM-) and RCM(DM+) patients presented increased LV end-diastolic index and end-systolic volume index and decreased LV ejection fraction. LV GPS in all three directions and longitudinal PDSR progressively declined from the control group to the RCM(DM-) group to the RCM(DM+) group (all p < 0.05). DM was an independent determinant of impaired LV GPS in the radial, circumferential, and longitudinal directions and longitudinal PDSR (β =  - 0.217, 0.176, 0.253, and - 0.263, all p < 0.05) in RCM patients. The multiparameter combination, including DM, showed an AUC of 0.81(95% CI 0.75-0.87) to predict decreased LV GLPS and an AUC of 0.69 (95% CI 0.62-0.76) to predict decreased LV longitudinal PDSR.

CONCLUSIONS

DM may have an additive deleterious effect on LV dysfunction in patients with RCM, especially diastolic dysfunction in RCM patients, indicating the importance of early identification and initiation of treatment of DM in patients with RCM.

Assessment of Prevalence, Clinical Characteristics, and Risk Factors Associated With "Low Flow State" Using Cardiac Magnetic Resonance

Objective

To assess prevalence, clinical characteristics, and risk factors associated with low flow state (LFS) in a multiethnic population with normal left ventricular ejection fraction (LVEF).

Patients and Methods

The study included 4398 asymptomatic participants undergoing cardiac magnetic resonance from July 17, 2000, to August 29, 2002. Left ventricular (LV) mass, volume, and myocardial contraction fraction were assessed. Low flow state was defined as stroke volume index (SVi of <35 mL/m2). Clinical characteristics, cardiac risk factors, and cardiac magnetic resonance findings were compared between LFS and normal flow state (NFS) groups (NFS: SVi of ≥35 mL/m2).

Results

There were significant differences in the prevalence of LFS in different ethnic groups. Individuals with LFS were older (66±9.6 vs 61±10 years; P<.0001). The prevalence of LFS was 19% in the group aged older than 70 years. The logistic multivariable regression analysis found that age was independently associated with LFS. The LFS group had significantly higher prevalence of diabetes (30% vs 24%; P=.001), LV mass-volume ratio (1.13±0.22 vs 0.91±0.15; P<.0001), inflammatory markers, a lower LV mass index (59±10 vs 65±11 kg/m2; P<.001), lower myocardial contraction fraction (58.1±10.6% vs 75.7±13%; P<.001), and a lower left atrial size index (32.2±4.6 vs 36.7±5.9 mm/m2; P<.0001) than NFS.

Conclusion

Low flow state may be considered an under-recognized clinical entity associated with increasing age, multiple risk factors, increased inflammatory markers, a lower LV mass index, and suboptimal myocardial performance despite the presence of normal LVEF and absence of valvular disease.

Cardiac Magnetic Resonance Imaging in Appraising Myocardial Strain and Biomechanics: A Current Overview

Subclinical alterations in myocardial structure and function occur early during the natural disease course. In contrast, clinically overt signs and symptoms occur during late phases, being associated with worse outcomes. Identification of such subclinical changes is critical for timely diagnosis and accurate management. Hence, implementing cost-effective imaging techniques with accuracy and reproducibility may improve long-term prognosis. A growing body of evidence supports using cardiac magnetic resonance (CMR) to quantify deformation parameters. Tissue-tagging (TT-CMR) and feature-tracking CMR (FT-CMR) can measure longitudinal, circumferential, and radial strains and recent research emphasize their diagnostic and prognostic roles in ischemic heart disease and primary myocardial illnesses. Additionally, these methods can accurately determine LV wringing and functional dynamic geometry parameters, such as LV torsion, twist/untwist, LV sphericity index, and long-axis strain, and several studies have proved their utility in prognostic prediction in various cardiovascular patients. More recently, few yet important studies have suggested the superiority of fast strain-encoded imaging CMR-derived myocardial strain in terms of accuracy and significantly reduced acquisition time, however, more studies need to be carried out to establish its clinical impact. Herein, the current review aims to provide an overview of currently available data regarding the role of CMR in evaluating myocardial strain and biomechanics.

Triglyceride-glucose index in the development of heart failure and left ventricular dysfunction: analysis of the ARIC study

AIMS

We aimed to investigate whether the triglyceride-glucose (TyG) index, an easy-calculated and reliable surrogate of insulin resistance, was associated with the development of heart failure (HF) and left ventricular (LV) dysfunction.

METHODS AND RESULTS

A total of 12 374 participants (mean age: 54.1 ± 5.7 years, male: 44.7%) free of history of HF and coronary heart disease at baseline from the Atherosclerosis Risk in Communities study were included. The TyG index was calculated as ln[fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. The long-term TyG index was calculated as the updated cumulative average TyG index using all available TyG index from baseline to the events of HF or the end of follow-up. We evaluated the associations of both the baseline and the long-term TyG index with incident HF using Cox regression analysis. We also analysed the effect of the TyG index on LV structure and function among 4889 participants with echocardiographic data using multivariable linear regression analysis. There were 1958 incident HF cases over a median follow-up of 22.5 years. After adjusting for potential confounders, 1-SD (0.60) increase in the baseline TyG index was associated with a 15% higher risk of HF development [hazard ratio (HR): 1.15, 95% confidence interval (CI): 1.10-1.21]. Compared with participants in the lowest quartile of the baseline TyG index, those in the highest quartile had a greater risk of incident HF [HR (95% CI): 1.25 (1.08-1.45)]. In terms of LV structure and function, a greater baseline TyG index was associated with adverse LV remodelling and LV dysfunction. Similar results were found for the long-term TyG index.

CONCLUSION

In a community-based cohort, we found that a greater TyG index was significantly associated with a higher risk of incident HF and impaired LV structure and function.

Cardiovascular outcomes trials: a paradigm shift in the current management of type 2 diabetes

Cardiovascular disease (CVD) is the leading cause of mortality and morbidity in patients with type 2 diabetes (T2D). Historical concerns about cardiovascular (CV) risks associated with certain glucose-lowering medications gave rise to the introduction of cardiovascular outcomes trials (CVOTs). Initially implemented to help monitor the CV safety of glucose-lowering drugs in patients with T2D, who either had established CVD or were at high risk of CVD, data that emerged from some of these trials started to show benefits. Alongside the anticipated CV safety of many of these agents, evidence for certain sodium-glucose transporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have revealed potential cardioprotective effects in patients with T2D who are at high risk of CVD events. Reductions in 3-point major adverse CV events (3P-MACE) and CV death have been noted in some of these CVOTs, with additional benefits including reduced risks of hospitalisation for heart failure, progression of renal disease, and all-cause mortality. These new data are leading to a paradigm shift in the current management of T2D, with international guidelines now prioritising SGLT2 inhibitors and/or GLP-1 RAs in certain patient populations. However, clinicians are faced with a large volume of CVOT data when seeking to use this evidence base to bring opportunities to improve CV, heart failure and renal outcomes, and even reduce mortality, in their patients with T2D. The aim of this review is to provide an in-depth summary of CVOT data-crystallising the key findings, from safety to efficacy-and to offer a practical perspective for physicians. Finally, we discuss the next steps for the post-CVOT era, with ongoing studies that may further transform clinical practice and improve outcomes for people with T2D, heart failure or renal disease.

Effects of diabetes mellitus on left ventricular function and remodeling in hypertensive patients with heart failure with reduced ejection fraction: assessment with 3.0 T MRI feature tracking

BACKGROUND

Heart failure with reduced ejection fraction (HFrEF) is a major health burden worldwide with high morbidity and mortality. Comorbidities of HFrEF complicate treatment and lead to poor prognosis, among which hypertension (HTN) and diabetes mellitus (DM) are common and frequently cooccur. DM was found to have additive effects on cardiac function and structure in hypertensive patients, while its effects on the HFrEF cohort in the context of HTN remain unclear.

METHODS

A total of 171 patients with HFrEF were enrolled in our study, consisting of 51 HFrEF controls, 72 hypertensive HFrEF patients (HTN-HFrEF [DM-]) and 48 hypertensive HFrEF patients with comorbid DM (HTN-HFrEF [DM+]). Cardiac MRI-derived left ventricular (LV) strains, including global radial (GRPS), circumferential (GCPS) and longitudinal (GLPS) peak strain, and remodeling parameters were measured and compared among groups. The determinants of impaired LV function and LV remodeling in HFrEF patients were investigated by multivariable linear regression analyses.

RESULTS

Despite a similar LV ejection fraction, patients in the HTN-HFrEF (DM+) and HTN-HFrEF (DM-) groups showed a higher LV mass index and LV remodeling index than those in the HFrEF control group (all p < 0.05). Compared with the HTN-HFrEF (DM-) and HFrEF control groups, the HTN-HFrEF (DM+) group exhibited the most severe GLPS impairment (p < 0.001). After adjustment for covariates in HFrEF patients, DM was found to be an independent determinant of impaired LV strains in all three directions (GRPS [β = - 0.189; p = 0.011], GCPS [β = 0.217; p = 0.005], GLPS [β = 0.237; p = 0.002]). HTN was associated with impaired GLPS (β = 0.185; p = 0.016) only. However, HTN rather than DM was associated with LV remodeling in HFrEF patients in the multivariable regression analysis (p < 0.05).

CONCLUSIONS

DM aggravated LV longitudinal dysfunction in hypertensive HFrEF patients without further changes in LV remodeling, indicating that HFrEF patients with comorbid HTN and DM may have a hidden high-risk phenotype of heart failure that requires more advanced and personalized management.

Insulin resistance surrogates and left ventricular hypertrophy in normotensive obese children

BACKGROUND

The relationship between different surrogates of insulin resistance and left ventricular geometry in obese children is still unclear.

OBJECTIVE

We sought to explore the relationship between commonly used measures of insulin sensitivity/resistance (homeostatic model assessment index, serum uric acid, and triglycerides to high-density lipoprotein cholesterol ratio) and left ventricular geometry in normotensive obese children.

METHODS

In this cross-sectional study, 32 normotensive obese children were examined. Transthoracic echocardiography was used to measure left ventricular mass index and relative wall thickness. Homeostasis model assessment index, serum uric acid level, and a ratio of triglycerides to high-density lipoprotein cholesterol were used as markers of the insulin resistance. Simple and partial correlation analyses (to control for the effects of body mass index) were conducted to explore relationship between studied variables and left ventricular mass index or relative wall thickness as outcome variables.

RESULTS

We found positive correlations between homeostasis model assessment index and relative wall thickness (r = 0.47, p = 0.03) which remained significant after controlling for the effect of body mass index, z-score (r = 0.48, p = 0.03). The cutoff level of homeostasis model assessment index with the optimum sensitivity (Sn) and specificity (Sp) derived from the receiver operating characteristic (ROC) curves for predicting concentric remodelling was ≥5.51 with Sn = 83.33 and Sp = 68.75.

CONCLUSION

There is a positive relationship between homeostasis model assessment index and relative wall thickness of obese normotensive children which may help to distinguish at risk obese normotensive children for the development of concentric left ventricular remodelling.

Evaluation of the effects of glycated hemoglobin on cardiac function in patients with short-duration type 2 diabetes mellitus: A cardiovascular magnetic resonance study

AIMS

To investigate the association between glycated hemoglobin (HbA1c) and myocardial dysfunction and to determine whether its association is independent of myocardial perfusion.

METHODS

Sixty-four patients with type 2 diabetes mellitus (T2DM) were recruited. They were divided into groups according to their HbA1c level: the controlled T2DM group (HbA1c < 7%) and uncontrolled T2DM groups (HbA1c ≥ 7%). Meanwhile, 30 age-matched healthy volunteers were included. All patients with T2DM and healthy controls underwent cardiovascular magnetic resonance imaging to evaluate the myocardial mechanics and perfusion parameters.

RESULTS

The circumferential and longitudinal peak strain (PS) (p = 0.009 and 0.002 respectively) and global radial, circumferential, and longitudinal peak strain diastolic strain rates (PDSRs) (p = 0.002, 0.001, and 0.001 respectively) were lower in the uncontrolled T2DM group than in the controls without diabetes. In multivariable linear regression analysis, HbA1c was independently related to all directions of the PS and PDSR. The myocardial perfusion parameters were not independently associated with the PS or PDSR.

CONCLUSIONS

Cardiac function is impaired in Chinese T2DM patients with poor glucose control (HbA1c ≥ 7%), with preserved left ventricular (LV) ejection fraction, and disease duration <10 years. Poor blood glucose control is an independent predictor of LV myocardial dysfunction for patients with short-term T2DM.

The impact of visceral and general obesity on vascular and left ventricular function and geometry: a cross-sectional magnetic resonance imaging study of the UK Biobank

Aims 

We aimed to evaluate the associations of body fat distribution with cardiovascular function and geometry in the middle-aged general population.

Methods and results 

Four thousand five hundred and ninety participants of the UK Biobank (54% female, mean age 61.1 ± 7.2 years) underwent cardiac magnetic resonance for assessment of left ventricular (LV) parameters [end-diastolic volume (EDV), ejection fraction (EF), cardiac output (CO), and index (CI)] and magnetic resonance imaging for body composition analysis [subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT)]. Body fat percentage (BF%) was assessed by bioelectrical impedance. Linear regressions were performed to assess the impact of visceral (VAT) and general (SAT and BF%) obesity on cardiac function and geometry. Visceral obesity was associated with a smaller EDV [VAT: β −1.74 (−1.15 to −2.33)], lower EF [VAT: β −0.24 (−0.12 to −0.35), SAT: β 0.02 (−0.04 to 0.08), and BF%: β 0.02 (−0.02 to 0.06)] and the strongest negative association with CI [VAT: β −0.05 (−0.06 to −0.04), SAT: β −0.02 (−0.03 to −0.01), and BF% β −0.01 (−0.013 to −0.007)]. In contrast, general obesity was associated with a larger EDV [SAT: β 1.01 (0.72–1.30), BF%: β 0.37 (0.23–0.51)] and a higher CO [SAT: β 0.06 (0.05–0.07), BF%: β 0.02 (0.01–0.03)]. In the gender-specific analysis, only men had a significant association between VAT and EF [β −0.35 (−0.19 to −0.51)].

Conclusion 

Visceral obesity was associated with a smaller LV EDV and subclinical lower LV systolic function in men, suggesting that visceral obesity might play a more important role compared to general obesity in LV remodelling.

Imaging Interstitial Fibrosis, Left Ventricular Remodeling, and Function in Stage A and B Heart Failure

Myocardial interstitial fibrosis is part of the advanced disease stage of most cardiovascular pathologies. It has been characterized histologically in various disease settings from hypertensive heart disease and diabetic cardiomyopathy to severe aortic stenosis. It is also involved in the process of aging. In cardiovascular medicine, myocardial interstitial fibrosis is associated with several adverse outcomes, especially heart failure (HF) and sudden cardiac death. Until recently, clinical measures of interstitial fibrosis could only be made by invasive myocardial biopsy. The availability of cardiac magnetic resonance (CMR) T1 mapping techniques allows for the indirect measurement of interstitial space characteristics and extracellular volume size, which is closely correlated with collagen content and interstitial infiltration by amyloid and other molecules. There has been significant improvement in the accuracy and reproducibility of T1 acquisition sequences in the last decade; however, the correct use of this technique requires a solid CMR expertise in daily imaging practice. CMR has become the gold standard to assess left ventricular (LV) remodeling and functional features associated with interstitial fibrosis. These features can be detected in the early stages of HF. The main objective of this paper is to review the relevant results of preclinical and clinical observational studies that demonstrate the prognostic impact of interstitial fibrosis assessed by T1 mapping, as well as adverse left ventricular remodeling, as determinants of HF. Therefore, this review focuses on the pathological mechanisms underlying LV remodeling and interstitial fibrosis, in addition to the technical considerations involved in the assessment of interstitial LV fibrosis by CMR. It provides a thorough review of clinical evidence that demonstrates the association of interstitial fibrosis and other-CMR derived LV phenotypes with Stages A and B HF.

Metabolic syndrome and myocardium steatosis in subclinical type 2 diabetes mellitus: a 1H-magnetic resonance spectroscopy study

BACKGROUND

Metabolic syndrome (MetS) is a cluster of metabolic abnormalities that collectively cause an increased risk of type 2 diabetes mellitus (T2DM) and nonatherosclerotic cardiovascular disease. This study aimed to evaluate the role of myocardial steatosis in T2DM patients with or without MetS, as well as the relationship between subclinical left ventricular (LV) myocardial dysfunction and myocardial steatosis.

METHODS AND MATERIALS

We recruited 53 T2DM patients and 20 healthy controls underwent cardiac magnetic resonance examination. All T2DM patients were subdivide into two group: MetS group and non-MetS. LV deformation, perfusion parameters and myocardial triglyceride (TG) content were measured and compared among these three groups. Pearson's and Spearman analysis were performed to investigate the correlation between LV cardiac parameters and myocardial steatosis. The receiver operating characteristic curve (ROC) was performed to illustrate the relationship between myocardial steatosis and LV subclinical myocardial dysfunction.

RESULTS

An increase in myocardial TG content was found in the MetS group compared with that in the other groups (MetS vs. non-MetS: 1.54 ± 0.63% vs. 1.16 ± 0.45%; MetS vs. normal: 1.54 ± 0.63% vs. 0.61 ± 0.22%; all p < 0.001). Furthermore, reduced LV deformation [reduced longitudinal and radial peak strain (PS); all p < 0.017] and microvascular dysfunction [increased time to maximum signal intensity (TTM) and reduced Upslope; all p < 0.017)] was found in the MetS group. Myocardial TG content was positively associated with MetS (r = 0.314, p < 0.001), and it was independently associated with TTM (β = 0.441, p < 0.001) and LV longitudinal PS (β = 0.323, p = 0.021). ROC analysis exhibited that myocardial TG content might predict the risk of decreased LV longitudinal myocardial deformation (AUC = 0.74) and perfusion function (AUC = 0.71).

CONCLUSION

Myocardial TG content increased in T2DM patients with concurrent MetS. Myocardial steatosis was positively associated with decreased myocardial deformation and perfusion dysfunction, which may be an indicator for predicting diabetic cardiomyopathy.

Mechanisms underlying diabetic cardiomyopathy: From pathophysiology to novel therapeutic targets

Diabetic cardiomyopathy (DC) is defined as a clinical condition of cardiac dysfunction that occurs in the absence of coronary atherosclerosis, valvular disease, and hypertension in patients with diabetes mellitus (DM). Despite the increasing worldwide prevalence of DC, due to the global epidemic of DM, the underlying pathophysiology of DC has not been fully elucidated. In addition, the clinical criteria for diagnosing DC have not been established, and specific therapeutic options are not currently available. The current paradigm suggests the impaired cardiomyocyte function arises due to a number of DM-related metabolic disturbances including hyperglycemia, hyperinsulinemia, and hyperlipidemia, which lead to diastolic dysfunction and signs and symptoms of heart failure. Other factors, which have been implicated in the progression of DC, include mitochondrial dysfunction, increased oxidative stress, impaired calcium handling, inflammation, and cardiomyocyte apoptosis. Herein, we review the current theories surrounding the occurrence and progression of DC, and discuss the recent advances in diagnostic methodologies and therapeutic strategies. Moreover, apart from conventional animal DC models, we highlight alternative disease models for studying DC such as the use of patient-derived human induced pluripotent stem cells (hiPSCs) for studying the mechanisms underlying DC. The ability to obtain hiPSC-derived cardiomyocytes from DM patients with a DC phenotype could help identify novel therapeutic targets for preventing and delaying the progression of DC, and for improving clinical outcomes in DM patients.

Mitochondrial ROS Formation in the Pathogenesis of Diabetic Cardiomyopathy

Diabetic cardiomyopathy is a result of diabetes-induced changes in the structure and function of the heart. Hyperglycemia affects multiple pathways in the diabetic heart, but excessive reactive oxygen species (ROS) generation and oxidative stress represent common denominators associated with adverse tissue remodeling. Indeed, key processes underlying cardiac remodeling in diabetes are redox sensitive, including inflammation, organelle dysfunction, alteration in ion homeostasis, cardiomyocyte hypertrophy, apoptosis, fibrosis, and contractile dysfunction. Extensive experimental evidence supports the involvement of mitochondrial ROS formation in the alterations characterizing the diabetic heart. In this review we will outline the central role of mitochondrial ROS and alterations in the redox status contributing to the development of diabetic cardiomyopathy. We will discuss the role of different sources of ROS involved in this process, with a specific emphasis on mitochondrial ROS producing enzymes within cardiomyocytes. Finally, the therapeutic potential of pharmacological inhibitors of ROS sources within the mitochondria will be discussed.

Systemic ventricular strain and torsion are predictive of elevated serum NT-proBNP in Fontan patients: a magnetic resonance study

Background

This study aimed to investigate the associations between cardiac strain, cardiac torsion, ventricular volumes, and ventricular ejection fraction, with N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in Fontan patients who were age- and gender-matched with healthy control subjects.

Methods

Cardiovascular magnetic resonance (CMR) studies performed in 22 (15 male, 7 female) patients with single-ventricle physiology (all morphological left ventricles) palliated with Fontan and 17 (10 male, 7 female) age- and gender-matched healthy children volunteers were retrospectively analyzed. Serum NT-proBNP levels were obtained in Fontan subjects. Standard post-processing of CMR images included systemic ventricular end-diastolic and end-systolic volumes, stroke volume, cardiac mass, atrioventricular regurgitation, and ejection fraction. CMR tissue tracking (TT) software was used to quantify global longitudinal strain (GLS), global radial strain (GRS), and global circumferential strain (GCS) and torsion of the systemic ventricle. Pearson and Spearman correlation coefficients were used in comparisons of correlations between NT-proBNP and functional parameters in repair Fontan patients. Intra-observer and inter-observer variability of CMR strain and torsion values were determined from 10 randomly selected Fontan subjects and 10 randomly selected control subjects.

Results

GLS was significantly lower in Fontan patients than in control subjects (-15.19±2.94 vs. -19.97±1.70; P<0.001). GLS was not significantly different between normal NT-proBNP levels and high NT-proBNP levels in Fontan patients (-15.59±2.72 vs. -14.62±3.32; P=0.462). The GCS of repair Fontan patients was not significantly lower than that of the control group (-16.76±3.27 vs. -17.88±2.26; P=0.235). GCS was significantly different between normal and high NT-proBNP levels group in Fontan patients (-17.95±2.43 vs. -15.04±3.67; P=0.036). The peak systolic torsion and peak systolic torsion rates were significantly lower in Fontan patients than in control subjects (0.81±0.41 vs. 1.07±0.36, P=0.044; 7.36±3.41 vs. 9.85±2.61, P=0.017). Peak systolic torsion was significantly lower in Fontan patients with normal NT-proBNP levels than in high NT-proBNP subjects (0.67±0.43 vs. 1.01±0.29; P=0.036). GCS and torsion were more strongly correlated with NT-proBNP in the patient group (r=0.541 for GCS; r=0.588 for torsion, P<0.01). The parameters of strain and torsion could be reproduced with sufficient accuracy by intra-observer agreement(biases =0.04 for GLS; biases =0.66 for GCS; biases =1.03 for GRS; biases =0.04 for torsion) and inter-observer agreement (biases =0.32 for GLS; biases =0.85 for GCS; biases =1.52 for GRS; biases =0.18 for torsion).

Conclusions

GLS is an earlier marker of contractile dysfunction in repair Fontan patients. Peak systolic torsion may be a biomarker for determining subclinical dysfunction, as it is more strongly correlated with serum biomarkers of ventricular function than ventricular size or ejection fraction.

Journal of Cardiovascular Magnetic Resonance: 2017/2018 in review

There were 89 articles published in the Journal of Cardiovascular Magnetic Resonance (JCMR) in 2017, including 76 original research papers, 4 reviews, 5 technical notes, 1 guideline, and 3 corrections. The volume was down slightly from 2017 with a corresponding 15% decrease in manuscript submissions from 405 to 346 and thus reflects a slight increase in the acceptance rate from 25 to 26%. The decrease in submissions for the year followed the initiation of the increased author processing charge (APC) for Society for Cardiovascular Magnetic Resonance (SCMR) members for manuscripts submitted after June 30, 2018. The quality of the submissions continues to be high. The 2018 JCMR Impact Factor (which is published in June 2019) was slightly lower at 5.1 (vs. 5.46 for 2017; as published in June 2018. The 2018 impact factor means that on average, each JCMR published in 2016 and 2017 was cited 5.1 times in 2018. Our 5 year impact factor was 5.82.In accordance with Open-Access publishing guidelines of BMC, the JCMR articles are published on-line in a continuus fashion in the chronologic order of acceptance, with no collating of the articles into sections or special thematic issues. For this reason, over the years, the Editors have felt that it is useful for the JCMR audience to annually summarize the publications into broad areas of interest or themes, so that readers can view areas of interest in a single article in relation to each other and contemporaneous JCMR publications. In this publication, the manuscripts are presented in broad themes and set in context with related literature and previously published JCMR papers to guide continuity of thought within the journal. In addition, as in the past two years, I have used this publication to also convey information regarding the editorial process and as a "State of our JCMR."This is the 12th year of JCMR as an open-access publication with BMC (formerly known as Biomed Central). The timing of the JCMR transition to the open access platform was "ahead of the curve" and a tribute to the vision of Dr. Matthias Friedrich, the SCMR Publications Committee Chair and Dr. Dudley Pennell, the JCMR editor-in-chief at the time. The open-access system has dramatically increased the reading and citation of JCMR publications and I hope that you, our authors, will continue to send your very best, high quality manuscripts to JCMR for consideration. It takes a village to run a journal and I thank our very dedicated Associate Editors, Guest Editors, Reviewers for their efforts to ensure that the review process occurs in a timely and responsible manner. These efforts have allowed the JCMR to continue as the premier journal of our field. This entire process would also not be possible without the dedication and efforts of our managing editor, Diana Gethers. Finally, I thank you for entrusting me with the editorship of the JCMR as I begin my 4th year as your editor-in-chief. It has been a tremendous experience for me and the opportunity to review manuscripts that reflect the best in our field remains a great joy and highlight of my week!