Impact of gender on the myocardial metabolic response to obesity

Vasodilator reactive oxygen species ameliorate perturbed myocardial oxygen delivery in exercising swine with multiple comorbidities

Multiple common cardiovascular comorbidities produce coronary microvascular dysfunction. We previously observed in swine that a combination of diabetes mellitus (DM), high fat diet (HFD) and chronic kidney disease (CKD) induced systemic inflammation, increased oxidative stress and produced coronary endothelial dysfunction, altering control of coronary microvascular tone via loss of NO bioavailability, which was associated with an increase in circulating endothelin (ET). In the present study, we tested the hypotheses that (1) ROS scavenging and (2) ETA+B-receptor blockade improve myocardial oxygen delivery in the same female swine model. Healthy female swine on normal pig chow served as controls (Normal). Five months after induction of DM (streptozotocin, 3 × 50 mg kg-1 i.v.), hypercholesterolemia (HFD) and CKD (renal embolization), swine were chronically instrumented and studied at rest and during exercise. Sustained hyperglycemia, hypercholesterolemia and renal dysfunction were accompanied by systemic inflammation and oxidative stress. In vivo ROS scavenging (TEMPOL + MPG) reduced myocardial oxygen delivery in DM + HFD + CKD swine, suggestive of a vasodilator influence of endogenous ROS, while it had no effect in Normal swine. In vitro wire myography revealed a vasodilator role for hydrogen peroxide (H2O2) in isolated small coronary artery segments from DM + HFD + CKD, but not Normal swine. Increased catalase activity and ceramide production in left ventricular myocardial tissue of DM + HFD + CKD swine further suggest that increased H2O2 acts as vasodilator ROS in the coronary microvasculature. Despite elevated ET-1 plasma levels in DM + HFD + CKD swine, ETA+B blockade did not affect myocardial oxygen delivery in Normal or DM + HFD + CKD swine. In conclusion, loss of NO bioavailability due to 5 months exposure to multiple comorbidities is partially compensated by increased H2O2-mediated coronary vasodilation.

Myocardial Metabolic Reprogramming in HFpEF

Heart failure (HF) caused by structural or functional cardiac abnormalities is a significant cause of morbidity and mortality worldwide. While HF with reduced ejection fraction (HErEF) is well understood, more than half of patients have HF with preserved ejection fraction (HFpEF). Currently, the treatment for HFpEF primarily focuses on symptom alleviation, lacking specific drugs. The stressed heart undergoes metabolic switches in substrate preference, which is a compensatory process involved in cardiac pathological remodeling. Although metabolic reprogramming in HF has gained attention in recent years, its role in HFpEF still requires further elucidation. In this review, we present a summary of cardiac mitochondrial dysfunction and cardiac metabolic reprogramming in HFpEF. Additionally, we emphasize potential therapeutic approaches that target metabolic reprogramming for the treatment of HFpEF.

Cardiac Molecular Analysis Reveals Aging-Associated Metabolic Alterations Promoting Glycosaminoglycans Accumulation Via Hexosamine Biosynthetic Pathway

Age is a prominent risk factor for cardiometabolic disease, and often leads to heart structural and functional changes. However, precise molecular mechanisms underlying cardiac remodeling and dysfunction resulting from physiological aging per se remain elusive. Understanding these mechanisms requires biological models with optimal translation to humans. Previous research demonstrated that baboons undergo age-related reduction in ejection fraction and increased heart sphericity, mirroring changes observed in humans. The goal of this study was to identify early cardiac molecular alterations that precede functional adaptations, shedding light on the regulation of age-associated changes. We performed unbiased transcriptomics of left ventricle (LV) samples from female baboons aged 7.5-22.1 years (human equivalent ~30-88 years). Weighted-gene correlation network and pathway enrichment analyses were performed to identify potential age-associated mechanisms in LV, with histological validation. Myocardial modules of transcripts negatively associated with age were primarily enriched for cardiac metabolism, including oxidative phosphorylation, tricarboxylic acid cycle, glycolysis, and fatty-acid β-oxidation. Transcripts positively correlated with age suggest upregulation of glucose uptake, pentose phosphate pathway, and hexosamine biosynthetic pathway (HBP), indicating a metabolic shift towards glucose-dependent anabolic pathways. Upregulation of HBP commonly results in increased glycosaminoglycan precursor synthesis. Transcripts involved in glycosaminoglycan synthesis, modification, and intermediate metabolism were also upregulated in older animals, while glycosaminoglycan degradation transcripts were downregulated with age. These alterations would promote glycosaminoglycan accumulation, which was verified histologically. Upregulation of extracellular matrix (ECM)-induced signaling pathways temporally coincided with glycosaminoglycan accumulation. We found a subsequent upregulation of cardiac hypertrophy-related pathways and an increase in cardiomyocyte width. Overall, our findings revealed a transcriptional shift in metabolism from catabolic to anabolic pathways that leads to ECM glycosaminoglycan accumulation through HBP prior to upregulation of transcripts of cardiac hypertrophy-related pathways. This study illuminates cellular mechanisms that precede development of cardiac hypertrophy, providing novel potential targets to remediate age-related cardiac diseases.

Emerging Medical Therapies for the Treatment of Obesity in Women with Cardiovascular Diseases

PURPOSE OF REVIEW

In this review, the impact of obesity on cardiovascular disease in women and emerging anti-obesity pharmacologic treatments are discussed.

RECENT FINDINGS

Robust evidence demonstrates the burden of obesity across the lifespan in women and links obesity to a diverse set of cardiovascular diseases. Female-specific risk factors including sex hormones and pregnancy factors intersect with obesity and cardiovascular risk. Sustained weight loss has potential for cardiovascular benefits. Recent trials demonstrate cardiovascular benefits of emerging agents with weight loss effects including GLP-1 RA and SGLT2 inhibitors in women. Treatment and prevention strategies for cardiovascular disease in obese women should include integration of weight management strategies including the targeted use of emerging pharmacologic therapies.

Current status and emerging trends of cardiac metabolism from the past 20 years: A bibliometric study

Background

Abnormal cardiac metabolism is a key factor in the development of cardiovascular diseases. Consequently, there has been considerable emphasis on researching and developing drugs that regulate metabolism. This study employed bibliometric methods to comprehensively and objectively analyze the relevant literature, offering insights into the knowledge dynamics in this field.

Methods

The data source for this study was the Web of Science Core Collection (WoSCC), from which the collected data were imported into bibliometric software for analysis.

Results

The United States was the leading contributor, accounting for 38.33 % of publications. The University of Washington and Damian J. Tyler were the most active institution and author, respectively. The American Journal of Physiology-Heart and Circulatory Physiology, Journal of Molecular and Cellular Cardiology, Cardiovascular Research, Circulation Research, and American Journal of Physiology-Endocrinology and Metabolism were highly influential journals that published numerous high-quality articles on cardiac metabolism. Common keywords in this research area included heart failure, insulin resistance, skeletal muscle, mitochondria, as well as topic words such as cardiac metabolism, fatty acid oxidation, glucose metabolism, and myocardial metabolism. Co-citation analysis has shown that research on heart failure and in vitro modeling of cardiovascular disease has gained prominence in recent years and making it a research hotspot.

Conclusion

Research on cardiac metabolism is steadily growing, with a specific focus on heart failure and the interplay between mitochondrial dysfunction, insulin resistance, and cardiac metabolism. An emerging trend in this field involves the enhancement of maturation in human induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) through the manipulation of cardiac metabolism.

Cardiometabolic sex differences in adults born small for gestational age

Aim

This study aimed to assess the cardiometabolic sex similarities and differences in adults born small for gestational age.

Methods

This study was an ambispective cohort study from a birth registry in Barcelona, Spain, including 523 adult participants (20-40 years-old) subdivided as born small for gestational age (SGA, if birth weight <10th centile) or adequate fetal growth for gestational age (AGA). Cardiometabolic health was assessed by echocardiography, electrocardiogram, blood pressure measurement, vascular ultrasound, anthropometric measurements, and serum glycemia and lipid profile. Stratified analyses by sex were performed by estimation of adjusted absolute difference (AAD) using inverse probability weighting.

Results

Compared with AGA, the stratified analyses by sex showed a more pronounced reduction in ejection fraction [AAD: female -1.73 (95% CI -3.2 to -0.28) vs. male -1.33 (-3.19 to 0.52)] and increment in heart rate [female 3.04 (0.29-5.8) vs. male 2.25 (-0.82 to 5.31)] in SGA females compared with SGA males. In contrast, a more pronounced reduction in PR interval [female -1.36 (-6.15 to 3.42) vs. male -6.61 (-11.67 to -1.54)] and an increase in systolic blood pressure [female 0.06 (-2.7 to 2.81) vs. male 2.71 (-0.48 to 5.9)] and central-to-peripheral fat ratio [female 0.05 (-0.03 to 0.12) vs. male 0.40 (0.17-0.62)] were mainly observed in SGA male compared with SGA female.

Conclusions

Sex differences were observed in the effect of SGA on cardiometabolic endpoints with female being more prone to cardiac dysfunction and male to electrocardiographic, vascular, and metabolic changes. Future research including sex-stratification data is warranted.

Association between changes in predicted body composition and occurrence of heart failure: a nationwide population study

Background

Large population-based studies on the association between changes in body composition and the occurrence of heart failure (HF) are rare. We aimed to determine the association between changes in body composition, including the predicted body fat mass index (pBFMI), predicted appendicular skeletal muscle mass index (pASMI), and predicted lean body mass index (pLBMI), and the occurrence of HF.

Methods

For present study, 2,036,940 people who consecutively underwent national health examinations from 2010~2011 (baseline period) to 2012~2013 (follow-up period) were included. The pBFMI, pASMI, and pLBMI were indirectly investigated using validated anthropometric prediction equations from the Korean National Health and Nutrition Examination Survey cohort. The outcome was defined as at least two or more claims of HF.

Results

During a median of 7.59 years of follow-up, 22,172 participants (event rate, 1.09%) with HF were observed. Decreased changes in the pASMI and pLBMI were associated with the occurrence of HF among males (hazard ratio [HR] 0.966, 95% confidence interval (CI) [0.944-0.988]; HR 0.939, 95%CI [0.923-0.955], respectively) and females (HR 0.924, 95%CI [0.900-0.947]; HR 0.951, 95%CI [0.939-0.963], respectively). An increased change in the pBFMI was associated with the occurrence of HF in males (HR 1.017, 95%CI [1.001-1.034]). However, paradoxically, a change in the pBFMI was associated with the occurrence of HF in females (HR 0.925, 95%CI [0.909-0.942]).

Conclusion

Decreased skeletal muscle mass was related to the occurrence of HF. However, the relationship between a change in fat mass and the occurrence of HF was different and even paradoxical depending on sex.

Myocardial Work in Middle-Aged Adults with Overweight and Obesity: Associations with Sex and Central Arterial Stiffness

We explored global myocardial work index (GWI), a novel measure of myocardial function that integrates left ventricular (LV) hemodynamic load, in relation to sex and increased body mass index (BMI). We used data from 467 individuals (61% women, average age 47 ± 9 years and BMI 31.2 kg/m2) without known cardiac disease. Central arterial function was analysed by applanation tonometry. GWI was calculated from global longitudinal strain (GLS) and post-echocardiography supine blood pressure (BP). Covariables of GWI were identified in linear regression analyses. Women had higher BMI, aortic augmentation pressure (12 ± 7 vs. 8 ± 6 mmHg), LV GLS (20.0 ± 2.8 vs. 18.8 ± 2.8%), and GWI (2126 ± 385 vs. 2047 ± 389 mmHg%) than men (all p < 0.05). In univariable analyses, higher GWI was associated with female sex, higher age, systolic BP, LV wall stress, LV ejection fraction, left atrial size, LV ejection time, and with lower waist circumference (all p < 0.05). In multivariable analysis, adjusting for these correlates, female sex remained independently associated with higher GWI (β = 0.13, p = 0.007). After additional adjustment for aortic augmentation pressure or central pulse pressure, this association became non-significant. In conclusion, the higher GWI in women compared to men was mainly explained by increased LV workload due to higher aortic augmentation pressure in women.

Sex matters: the frequently overlooked importance of considering sex in computational models

Personalised medicine and the development of a virtual human or a digital twin comprises visions of the future of medicine. To realise these innovations, an understanding of the biology and physiology of all people are required if we wish to apply these technologies at a population level. Sex differences in health and biology is one aspect that has frequently been overlooked, with young white males being seen as the "average" human being. This has not been helped by the lack of inclusion of female cells and animals in biomedical research and preclinical studies or the historic exclusion, and still low in proportion, of women in clinical trials. However, there are many known differences in health between the sexes across all scales of biology which can manifest in differences in susceptibility to diseases, symptoms in a given disease, and outcomes to a given treatment. Neglecting these important differences in the development of any health technologies could lead to adverse outcomes for both males and females. Here we highlight just some of the sex differences in the cardio-respiratory systems with the goal of raising awareness that these differences exist. We discuss modelling studies that have considered sex differences and touch on how and when to create sex-specific models. Scientific studies should ensure sex differences are included right from the study planning phase and results reported using sex as a biological variable. Computational models must have sex-specific versions to ensure a movement towards personalised medicine is realised.

Oxidative stress and inflammation distinctly drive molecular mechanisms of diastolic dysfunction and remodeling in female and male heart failure with preserved ejection fraction rats

Heart failure with preserved ejection fraction (HFpEF) is a complex cardiovascular insufficiency syndrome presenting with an ejection fraction (EF) of greater than 50% along with different proinflammatory and metabolic co-morbidities. Despite previous work provided key insights into our understanding of HFpEF, effective treatments are still limited. In the current study we attempted to unravel the molecular basis of sex-dependent differences in HFpEF pathology. We analyzed left ventricular samples from 1-year-old female and male transgenic (TG) rats homozygous for the rat Ren-2 renin gene (mRen2) characterized with hypertension and diastolic dysfunction and compared it to age-matched female and male wild type rats (WT) served as control. Cardiomyocytes from female and male TG rats exhibited an elevated titin-based stiffness (F_passive), which was corrected to control level upon treatment with reduced glutathione indicating titin oxidation. This was accompanied with high levels of oxidative stress in TG rats with more prominent effects in female group. In vitro supplementation with heat shock proteins (HSPs) reversed the elevated F_passive indicating restoration of their cytoprotective function. Furthermore, the TG group exhibited high levels of proinflammatory cytokines with significant alterations in apoptotic and autophagy pathways in both sexes. Distinct alterations in the expression of several proteins between both sexes suggest their differential impact on disease development and necessitate distinct treatment options. Hence, our data suggested that oxidative stress and inflammation distinctly drive diastolic dysfunction and remodeling in female and male rats with HFpEF and that the sex-dependent mechanisms contribute to HF pathology.

Myocardial Metabolomics of Human Heart Failure With Preserved Ejection Fraction

BACKGROUND

The human heart primarily metabolizes fatty acids, and this decreases as alternative fuel use rises in heart failure with reduced ejection fraction (HFrEF). Patients with severe obesity and diabetes are thought to have increased myocardial fatty acid metabolism, but whether this is found in those who also have heart failure with preserved ejection fraction (HFpEF) is unknown.

METHODS

Plasma and endomyocardial biopsies were obtained from HFpEF (n=38), HFrEF (n=30), and nonfailing donor controls (n=20). Quantitative targeted metabolomics measured organic acids, amino acids, and acylcarnitines in myocardium (72 metabolites) and plasma (69 metabolites). The results were integrated with reported RNA sequencing data. Metabolomics were analyzed using agnostic clustering tools, Kruskal-Wallis test with Dunn test, and machine learning.

RESULTS

Agnostic clustering of myocardial but not plasma metabolites separated disease groups. Despite more obesity and diabetes in HFpEF versus HFrEF (body mass index, 39.8 kg/m2 versus 26.1 kg/m2; diabetes, 70% versus 30%; both P<0.0001), medium- and long-chain acylcarnitines (mostly metabolites of fatty acid oxidation) were markedly lower in myocardium from both heart failure groups versus control. In contrast, plasma levels were no different or higher than control. Gene expression linked to fatty acid metabolism was generally lower in HFpEF versus control. Myocardial pyruvate was higher in HFpEF whereas the tricarboxylic acid cycle intermediates succinate and fumarate were lower, as were several genes controlling glucose metabolism. Non-branched-chain and branched-chain amino acids (BCAA) were highest in HFpEF myocardium, yet downstream BCAA metabolites and genes controlling BCAA metabolism were lower. Ketone levels were higher in myocardium and plasma of patients with HFrEF but not HFpEF. HFpEF metabolomic-derived subgroups were differentiated by only a few differences in BCAA metabolites.

CONCLUSIONS

Despite marked obesity and diabetes, HFpEF myocardium exhibited lower fatty acid metabolites compared with HFrEF. Ketones and metabolites of the tricarboxylic acid cycle and BCAA were also lower in HFpEF, suggesting insufficient use of alternative fuels. These differences were not detectable in plasma and challenge conventional views of myocardial fuel use in HFpEF with marked diabetes and obesity and suggest substantial fuel inflexibility in this syndrome.

Western Diet Causes Heart Failure With Reduced Ejection Fraction and Metabolic Shifts After Diastolic Dysfunction and Novel Cardiac Lipid Derangements

Western diet (WD) impairs glucose tolerance and cardiac lipid dynamics, preceding heart failure with reduced ejection fraction (HFrEF) in mice. Unlike diabetic db/db mice with high cardiac triglyceride (TG) and rapid TG turnover, WD mice had high TG but slowed turnover, reducing lipolytic PPAR⍺ activation. WD deranged cardiac TG dynamics by imbalancing synthesis and lipolysis, with low cardiac TG lipase (ATGL), low ATGL co-activator, and high ATGL inhibitory peptide. By 24 weeks of WD, hearts shifted from diastolic dysfunction to diastolic dysfunction with HFrEF with decreases in GLUT4 and exogenous glucose oxidation and elevated β-hydroxybutyrate dehydrogenase 1 without increasing ketone oxidation.

Aldose reductase inhibition alleviates diabetic cardiomyopathy and is associated with a decrease in myocardial fatty acid oxidation

BACKGROUND

Cardiovascular diseases, including diabetic cardiomyopathy, are major causes of death in people with type 2 diabetes. Aldose reductase activity is enhanced in hyperglycemic conditions, leading to altered cardiac energy metabolism and deterioration of cardiac function with adverse remodeling. Because disturbances in cardiac energy metabolism can promote cardiac inefficiency, we hypothesized that aldose reductase inhibition may mitigate diabetic cardiomyopathy via normalization of cardiac energy metabolism.

METHODS

Male C57BL/6J mice (8-week-old) were subjected to experimental type 2 diabetes/diabetic cardiomyopathy (high-fat diet [60% kcal from lard] for 10 weeks with a single intraperitoneal injection of streptozotocin (75 mg/kg) at 4 weeks), following which animals were randomized to treatment with either vehicle or AT-001, a next-generation aldose reductase inhibitor (40 mg/kg/day) for 3 weeks. At study completion, hearts were perfused in the isolated working mode to assess energy metabolism.

RESULTS

Aldose reductase inhibition by AT-001 treatment improved diastolic function and cardiac efficiency in mice subjected to experimental type 2 diabetes. This attenuation of diabetic cardiomyopathy was associated with decreased myocardial fatty acid oxidation rates (1.15 ± 0.19 vs 0.5 ± 0.1 µmol min-1 g dry wt-1 in the presence of insulin) but no change in glucose oxidation rates compared to the control group. In addition, cardiac fibrosis and hypertrophy were also mitigated via AT-001 treatment in mice with diabetic cardiomyopathy.

CONCLUSIONS

Inhibiting aldose reductase activity ameliorates diastolic dysfunction in mice with experimental type 2 diabetes, which may be due to the decline in myocardial fatty acid oxidation, indicating that treatment with AT-001 may be a novel approach to alleviate diabetic cardiomyopathy in patients with diabetes.

The Association of Leptin with Left Ventricular Hypertrophy in End-Stage Kidney Disease Patients on Dialysis

Left ventricular hypertrophy (LVH) is a common cardiovascular complication in end-stage kidney disease (ESKD) patients. We aimed at studying the association of LVH with adiponectin and leptin levels, cardiovascular stress/injury biomarkers and nutritional status in these patients. We evaluated the LV mass (LVM) and calculated the LVM index (LVMI) in 196 ESKD patients on dialysis; the levels of hemoglobin, calcium, phosphorus, parathyroid hormone, albumin, adiponectin, leptin, N-terminal pro B-type natriuretic peptide (NT-proBNP) and growth differentiation factor (GDF)-15 were analyzed. ESKD patients with LVH (n = 131) presented higher NT-proBNP and GDF-15, lower hemoglobin and, after adjustment for gender, lower leptin levels compared with non-LVH patients. LVH females also showed lower leptin than the non-LVH female group. In the LVH group, LVMI presented a negative correlation with leptin and a positive correlation with NT-proBNP. Leptin emerged as an independent determinant of LVMI in both groups, and NT-proBNP in the LVH group. Low hemoglobin and leptin and increased calcium, NT-proBNP and dialysis vintage are associated with an increased risk of developing LVH. In ESKD patients on dialysis, LVH is associated with lower leptin values (especially in women), which are negatively correlated with LVMI, and with higher levels of biomarkers of myocardial stress/injury. Leptin and NT-proBNP appear as independent determinants of LVMI; dialysis vintage, hemoglobin, calcium, NT-proBNP and leptin emerged as predicting markers for LVH development. Further studies are needed to better understand the role of leptin in LVH in ESKD patients.

Obesity and heart failure with preserved ejection fraction: new insights and pathophysiological targets

Obesity and heart failure with preserved ejection fraction (HFpEF) represent two intermingling epidemics driving perhaps the greatest unmet health problem in cardiovascular medicine in the 21st century. Many patients with HFpEF are either overweight or obese, and recent data have shown that increased body fat and its attendant metabolic sequelae have widespread, protean effects systemically and on the cardiovascular system leading to symptomatic HFpEF. The paucity of effective therapies in HFpEF underscores the importance of understanding the distinct pathophysiological mechanisms of obese HFpEF to develop novel therapies. In this review, we summarize the current understanding of the cardiovascular and non-cardiovascular features of the obese phenotype of HFpEF, how increased adiposity might pathophysiologically contribute to the phenotype, and how these processes might be targeted therapeutically.

Relationship of body mass index to clinical outcomes after percutaneous coronary intervention

BACKGROUND

Elevated body mass index (BMI) demonstrates lower all-cause and cardiovascular mortalities compared with normal-weight or lean patients in chronic diseases. This study investigated relationships between BMI and clinical outcomes following percutaneous coronary intervention (PCI) in coronary artery disease (CAD) patients, together with the sex-specific impacts of BMI on mortality.

METHODS

We reviewed 1104 CAD patients who underwent PCI between 2006 and 2015. Patients were divided by BMI into three groups: lean, <18.5 kg/m² ; normal, 18.5-24.9 kg/m² ; and overweight/obese, ≥25 kg/m² . The primary endpoint was all-cause mortality, and the secondary endpoint was 3-point major adverse cardiovascular events (MACE).

RESULTS

Kaplan-Meier survival analysis demonstrated risks of all-cause death, and 3-point MACE were higher in lean patients compared with normal-weight and overweight/obese subjects (log-rank p < .001). Cox proportional hazard modelling showed overweight/obese was significantly associated with all-cause death (hazard ratio (HR) 0.68, 95% confidence interval (CI) 0.48-0.95; p = .03), and lean was significantly associated with 3-point MACE (HR 2.02, 95% CI 1.15-3.53; p = .01). Cox proportional hazard analysis with restricted cubic spline showed non-linear associations between BMI and both all-cause mortality and 3-point MACE (p for effect = .002 and = .003, respectively). No significant interaction was evident between sex and BMI for all-cause mortality (p for interaction = .104) or 3-point MACE (p for interaction =0.122).

CONCLUSIONS

Lean category was associated with adverse outcomes among CAD patients. An obesity paradox regarding the independent association of elevated BMI with reduced mortality after PCI is evident in both males and females.

A Deep Learning Algorithm for Detecting Acute Pericarditis by Electrocardiogram

(1) Background: Acute pericarditis is often confused with ST-segment elevation myocardial infarction (STEMI) among patients presenting with acute chest pain in the emergency department (ED). Since a deep learning model (DLM) has been validated to accurately identify STEMI cases via 12-lead electrocardiogram (ECG), this study aimed to develop another DLM for the detection of acute pericarditis in the ED. (2) Methods: This study included 128 ECGs from patients with acute pericarditis and 66,633 ECGs from patients visiting the ED between 1 January 2010 and 31 December 2020. The ECGs were randomly allocated based on patients to the training, tuning, and validation sets, at a 3:1:1 ratio. We used raw ECG signals to train a pericarditis-DLM and used traditional ECG features to train a machine learning model. A human–machine competition was conducted using a subset of the validation set, and the performance of the Philips automatic algorithm was also compared. STEMI cases in the validation set were extracted to analyze the DLM ability of differential diagnosis between acute pericarditis and STEMI using ECG. We also followed the hospitalization events in non-pericarditis cases to explore the meaning of false-positive predictions. (3) Results: The pericarditis-DLM exceeded the performance of all participating human experts and algorithms based on traditional ECG features in the human–machine competition. In the validation set, the pericarditis-DLM could detect acute pericarditis with an area under the receiver operating characteristic curve (AUC) of 0.954, a sensitivity of 78.9%, and a specificity of 97.7%. However, our pericarditis-DLM also misinterpreted 10.2% of STEMI ECGs as pericarditis cases. Therefore, we generated an integrating strategy combining pericarditis-DLM and a previously developed STEMI-DLM, which provided a sensitivity of 73.7% and specificity of 99.4%, to identify acute pericarditis in patients with chest pains. Compared to the true-negative cases, patients with false-positive results using this strategy were associated with higher risk of hospitalization within 3 days due to cardiac disorders (hazard ratio (HR): 8.09; 95% confidence interval (CI): 3.99 to 16.39). (4) Conclusions: The AI-enhanced algorithm may be a powerful tool to assist clinicians in the early detection of acute pericarditis and differentiate it from STEMI using 12-lead ECGs.

Repository Describing the Anatomical, Physiological, and Biological Changes in an Obese Population to Inform Physiologically Based Pharmacokinetic Models

Background

Obesity is associated with physiological changes that can affect drug pharmacokinetics. Obese individuals are underrepresented in clinical trials, leading to a lack of evidence-based dosing recommendations for many drugs. Physiologically based pharmacokinetic (PBPK) modelling can overcome this limitation but necessitates a detailed description of the population characteristics under investigation.

Objective

The purpose of this study was to develop and verify a repository of the current anatomical, physiological, and biological data of obese individuals, including population variability, to inform a PBPK framework.

Methods

A systematic literature search was performed to collate anatomical, physiological, and biological parameters for obese individuals. Multiple regression analyses were used to derive mathematical equations describing the continuous effect of body mass index (BMI) within the range 18.5–60 kg/m² on system parameters.

Results

In total, 209 studies were included in the database. The literature reported mostly BMI-related changes in organ weight, whereas data on blood flow and biological parameters (i.e. enzyme abundance) were sparse, and hence physiologically plausible assumptions were made when needed. The developed obese population was implemented in Matlab^® and the predicted system parameters obtained from 1000 virtual individuals were in agreement with observed data from an independent validation obese population. Our analysis indicates that a threefold increase in BMI, from 20 to 60 kg/m², leads to an increase in cardiac output (50%), liver weight (100%), kidney weight (60%), both the kidney and liver absolute blood flows (50%), and in total adipose blood flow (160%).

Conclusion

The developed repository provides an updated description of a population with a BMI from 18.5 to 60 kg/m² using continuous physiological changes and their variability for each system parameter. It is a tool that can be implemented in PBPK models to simulate drug pharmacokinetics in obese individuals.

Metformin and high-sensitivity cardiac troponin I and T trajectories in type 2 diabetes patients: a post-hoc analysis of a randomized controlled trial

BACKGROUND

Metformin has favorable effects on cardiovascular outcomes in both newly onset and advanced type 2 diabetes, as previously reported findings from the UK Prospective Diabetes Study and the HOME trial have demonstrated. Patients with type 2 diabetes present with chronically elevated circulating cardiac troponin levels, an established predictor of cardiovascular endpoints and prognostic marker of subclinical myocardial injury. It is unknown whether metformin affects cardiac troponin levels. The study aimed to evaluate cardiac troponin I and T trajectories in patients with diabetes treated either with metformin or placebo.

METHODS

This study is a post-hoc analysis of a randomized controlled trial (HOME trial) that included 390 patients with advanced type 2 diabetes randomized to 850 mg metformin or placebo up to three times daily concomitant to continued insulin treatment. Cardiac troponin I and T concentrations were measured at baseline and after 4, 17, 30, 43 and 52 months. We evaluated cardiac troponin trajectories by linear mixed-effects modeling, correcting for age, sex, smoking status and history of cardiovascular disease.

RESULTS

This study enrolled 390 subjects, of which 196 received metformin and 194 received placebo. In the treatment and placebo groups, mean age was 64 and 59 years; with 50% and 58% of subjects of the female sex, respectively. Despite the previously reported reduction of macrovascular disease risk in this cohort by metformin, linear mixed-effects regression modelling did not reveal evidence for an effect on cardiac troponin I and cardiac troponin T levels [- 8.4% (- 18.6, 3.2), p = 0.150, and - 4.6% (- 12, 3.2), p = 0.242, respectively]. A statistically significant time-treatment interaction was found for troponin T [- 1.6% (- 2.9, - 0.2), p = 0.021] but not troponin I concentrations [- 1.5% (- 4.2, 1.2), p = 0.263].

CONCLUSIONS

In this post-hoc analysis of a 4.3-year randomized controlled trial, metformin did not exert a clinically relevant effect on cardiac troponin I and cardiac troponin T levels when compared to placebo. Cardioprotective effects of the drug observed in clinical studies are not reflected by a reduction in these biomarkers of subclinical myocardial injury. Trial registration ClinicalTrials.gov identifier NCT00375388.

Myocardial perfusion by CMR coronary sinus flow shows sex differences and lowered perfusion at stress in patients with suspected microvascular angina

Background

Methods

Results

Conclusions

Myocardial efficiency in patients with different aetiologies and stages of heart failure

AIMS

Myocardial external efficiency (MEE) is the ratio of cardiac work in relation with energy expenditure. We studied MEE in patients with different aetiologies and stages of heart failure (HF) to discover the role and causes of deranged MEE. In addition, we explored the impact of patient characteristics such as sex, body mass index (BMI), and age on myocardial energetics.

METHODS AND RESULTS

Cardiac energetic profiles were assessed with 11C-acetate positron emission tomography (PET) and left ventricular ejection fraction (LVEF) was acquired with echocardiography. MEE was studied in 121 participants: healthy controls (n = 20); HF patients with reduced (HFrEF; n = 25) and mildly reduced (HFmrEF; n = 23) LVEF; and patients with asymptomatic (AS-asymp; n = 38) and symptomatic (AS-symp; n = 15) aortic stenosis (AS). Reduced MEE coincided with symptoms of HF irrespective of aetiology and declined in tandem with deteriorating LVEF. Patients with AS-symp and HFmrEF had reduced MEE as compared with controls (22.2 ± 4.9%, P = 0.041 and 20.0 ± 4.2%, P < 0.001 vs. 26.1 ± 5.8% in controls) and a further decline was observed in patients with HFrEF (14.7 ± 6.3%, P < 0.001). Disproportionate left ventricular hypertrophy was a major cause of reduced MEE. Female sex (P < 0.001), a lower BMI (P = 0.001), and advanced age (P = 0.03) were associated with a lower MEE.

CONCLUSION

MEE was reduced in patients with HFrEF, HFmrEF, and HF due to pressure overload and MEE may therefore constitute a treatment target in HF. Patients with LVH, advanced age, female sex, and low BMI had more pronounced reduction in MEE and personalized treatment within these patient subgroups could be relevant.

Sex-specific pattern of left ventricular hypertrophy and diastolic function in patients with type 2 diabetes mellitus

AIMS

Few prospective studies have evaluated sex-specific pattern, natural progression of left ventricular (LV) remodelling, and diastolic dysfunction in patients with type 2 diabetes (T2DM). The aim of this study was to study the sex-specific prevalence, longitudinal changes of LV remodelling, and diastolic dysfunction in patients with T2DM. Further, the prognostic value of diastolic function in women and men was also evaluated.

METHODS AND RESULTS

A total of 350 patients with T2DM (mean age 61 ± 11 years; women, 48.3%) was recruited. Detailed echocardiography was performed at baseline and after 25 months. A major adverse cardiovascular event (MACE) was defined as cardiovascular death, heart failure hospitalization, or myocardial infarction. Despite a similar age, prevalence of hypertension and body mass index, women had a higher prevalence of LV hypertrophy and diastolic dysfunction at baseline and follow-up compared with men. A total of 21 patients developed MACE (5 cardiovascular death, 9 hospitalization for heart failure, and 7 myocardial infarction) during a median follow-up of 56 months. Women with diastolic dysfunction had a higher incidence of MACE than those with normal diastolic function but this association was neutral in men. Multivariable Cox-regression analysis indicated that diastolic dysfunction was associated with MACE in women [hazard ratio = 6.30; 95% confidence interval (CI) = 1.06-37.54; P < 0.05] but not men (hazard ratio = 2.29, 95% CI = 0.67-7.89; P = 0.19).

CONCLUSION

LV hypertrophy and diastolic dysfunction, both at baseline and follow-up, were more common in women than men. Pre-clinical diastolic dysfunction was independently associated with MACE only in women with T2DM but was neutral in men.

Series of myocardial FDG uptake requiring considerations of myocardial abnormalities in FDG-PET/CT

Distinct from cardiac PET performed with preparation to control physiological FDG uptake in the myocardium, standard FDG-PET/CT performed with 4-6 h of fasting will show variation in myocardial FDG uptake. For this reason, important signs of myocardial and pericardial abnormality revealed by myocardial FDG uptake tend to be overlooked. However, recognition of possible underlying disease will support further patient management to avoid complications due to the disease. This review demonstrates the mechanism of FDG uptake in the myocardium, discusses the factors affecting uptake, and provides notable image findings that may suggest underlying disease.

Pathophysiologic importance of visceral adipose tissue in women with heart failure and preserved ejection fraction

AIMS

Central obesity is a major risk factor for heart failure with preserved ejection fraction (HFpEF), particularly in women, but the mechanisms remain unclear. We hypothesized that sex-specific differences in visceral adipose tissue (VAT) content would differentially relate to haemodynamic severity of HFpEF in women and men.

METHODS AND RESULTS

Abdominal computed tomography (CT) and invasive haemodynamic exercise testing were performed in 105 subjects with HFpEF (63 women) and 105 age-, sex-, and body mass index-matched controls. Visceral adipose tissue area was quantified by CT. As compared with control women, VAT area was 34% higher in women with HFpEF (186 ± 112 vs. 139 ± 72 cm2, P = 0.006), while VAT area was not significantly different in men with or without HFpEF (294 ± 158 vs. 252 ± 92 cm2, P = 0.1). During exercise, pulmonary capillary wedge pressure (PCWP) increased markedly and to similar extent in both men and women with HFpEF. Women with increased VAT area displayed 33% higher PCWP during exercise compared with women with normal VAT area (28 ± 10 vs. 21 ± 10 mmHg, P = 0.001), whereas exercise PCWP was similar in men with or without excess VAT (24 ± 9 vs. 25 ± 6, P = 0.89). In women, each 100 cm2 increase in VAT area was associated with a 4.0 mmHg higher PCWP (95% CI 2.1, 6.0 mmHg; P < 0.0001), but there was no such relationship in men (interaction P = 0.009).

CONCLUSIONS

These data suggest that accumulation of excess VAT plays a distinct and important role in the pathophysiology of HFpEF preferentially in women. Further research is needed to better understand the mechanisms and treatment implications for visceral fat in HFpEF.

FoxO1 inhibition alleviates type 2 diabetes-related diastolic dysfunction by increasing myocardial pyruvate dehydrogenase activity

Type 2 diabetes (T2D) increases the risk for diabetic cardiomyopathy and is characterized by diastolic dysfunction. Myocardial forkhead box O1 (FoxO1) activity is enhanced in T2D and upregulates pyruvate dehydrogenase (PDH) kinase 4 expression, which inhibits PDH activity, the rate-limiting enzyme of glucose oxidation. Because low glucose oxidation promotes cardiac inefficiency, we hypothesize that FoxO1 inhibition mitigates diabetic cardiomyopathy by stimulating PDH activity. Tissue Doppler echocardiography demonstrates improved diastolic function, whereas myocardial PDH activity is increased in cardiac-specific FoxO1-deficient mice subjected to experimental T2D. Pharmacological inhibition of FoxO1 with AS1842856 increases glucose oxidation rates in isolated hearts from diabetic C57BL/6J mice while improving diastolic function. However, AS1842856 treatment fails to improve diastolic function in diabetic mice with a cardiac-specific FoxO1 or PDH deficiency. Our work defines a fundamental mechanism by which FoxO1 inhibition improves diastolic dysfunction, suggesting that it may be an approach to alleviate diabetic cardiomyopathy.

Sex differences in acute cardiovascular care: a review and needs assessment

Despite significant progress in the care of patients suffering from cardiovascular disease, there remains a persistent sex disparity in the diagnosis, management, and outcomes of these patients. These sex disparities are seen across the spectrum of cardiovascular care, but, are especially pronounced in acute cardiovascular care. The spectrum of acute cardiovascular care encompasses critically ill or tenuous patients with cardiovascular conditions that require urgent or emergent decision-making and interventions. In this narrative review, the disparities in the clinical course, management, and outcomes of six commonly encountered acute cardiovascular conditions, some with a known sex-predilection will be discussed within the basis of underlying sex differences in physiology, anatomy, and pharmacology with the goal of identifying areas where improvement in clinical approaches are needed.

Sex Differences in Heart Failure With Preserved Ejection Fraction

Background

The female preponderance in heart failure with preserved ejection fraction (HFpEF) is a distinguishing feature of this disorder, but the association of sex with degree of diastolic dysfunction and clinical outcomes among individuals with HFpEF remains unclear.

Methods and Results

We conducted a prospective, multicenter, observational study of patients with HFpEF (PURSUIT‐HFpEF [Prospective Multicenter Observational Study of Patients with Heart Failure with Preserved Ejection Fraction]: UMIN000021831). Between 2016 and 2019, 871 patients were enrolled from 26 hospitals (follow‐up: 399±349 days). We investigated sex‐related differences in diastolic dysfunction and postdischarge clinical outcomes in patients with HFpEF. The echocardiographic end point was diastolic dysfunction according to American Society of Echocardiography/European Association of Cardiovascular Imaging criteria. The clinical end point was a composite of all‐cause death and heart failure readmission. Women accounted for 55.2% (481 patients) of the overall cohort. Compared with men, women were older and had lower prevalence rates of hypertension, coronary artery disease, and chronic kidney disease. Women had diastolic dysfunction more frequently than men (52.8% versus 32.0%, P<0.001). The incidence of the clinical end point did not differ between women and men (women 36.1/100 person‐years versus men 30.5/100 person‐years, P=0.336). Female sex was independently associated with the echocardiographic end point (adjusted odds ratio, 2.839; 95% CI, 1.884–4.278; P<0.001) and the clinical end point (adjusted hazard ratio, 1.538; 95% CI, 1.143–2.070; P=0.004).

Conclusions

Female sex was independently associated with the presence of diastolic dysfunction and worse clinical outcomes in a cohort of elderly patients with HFpEF. Our results suggest that a sex‐specific approach is key to investigating the pathophysiology of HFpEF.

Registration

URL: https://upload.umin.ac.jp; Unique identifier: UMIN000021831.

Left ventricular myocardial oxygen demand and subclinical dysfunction in patients with severe obesity referred for bariatric surgery

BACKGROUND AND AIMS

Increased myocardial oxygen (O₂) demand carries higher cardiovascular risk in hypertension. We hypothesized that myocardial O₂ demand is increased in severe obesity and linked to early left ventricular (LV) dysfunction.

METHODS AND RESULTS

Baseline data from 106 severely obese subjects referred for gastric bypass surgery (42 ± 11 years, 74% women, body mass index [BMI] 41.9 ± 4.8 kg/m², 32% with hypertension) in the prospective FatWest (Bariatric Surgery on the West Coast of Norway) study was used. LV systolic function was assessed by biplane ejection fraction (EF), midwall shortening (MWS) and endocardial global longitudinal strain (GLS), and LV diastolic function by mitral annular early diastolic velocity (e'). Myocardial O₂ demand was estimated from the LV mass-wall stress-heart rate product (high if > 1.62 × 10⁶/2.29 × 10⁶ g kdyne/cm² bpm in women/men). High myocardial O₂ demand was found in 33% and associated with higher BMI and high prevalence of low GLS (65%) and low MWS (63%) despite normal EF. In ROC analyses, higher myocardial O₂ demand discriminated between patients with low vs. normal MWS and GLS (area under curve 0.71 and 0.63, p < 0.05). In successive multiple regression analyses, higher myocardial O₂ demand was associated with lower LV MWS, GLS and average e', respectively, independent of age, gender, BMI, pulse pressure, diabetes mellitus, and EF (all p < 0.05).

CONCLUSION

In obese patients without known heart disease and with normal EF referred for bariatric surgery, high myocardial O₂ demand is associated with lower myocardial function whether assessed by GLS or MWS independent of confounders. CLINICALTRIALS.

GOV IDENTIFIER

NCT01533142.

Sex-specific associations of obesity with exercise capacity and diastolic function in Koreans

BACKGROUND AND AIMS

Women with obesity are highly predominant among patients with heart failure with preserved ejection fraction (HFpEF). We aimed to elucidate sex-specific associations of obesity with exercise capacity and diastolic function.

METHODS AND RESULTS

Healthy individuals without known cardiovascular diseases undergoing cardiopulmonary exercise test and echocardiography (n = 736) were included and categorized into 4 groups according to their sex and obesity. Exercise capacity was lower in women than men. Obesity was associated with a lower exercise capacity in women (23.5 ± 7.3 vs. 21.3 ± 5.4 ml/kg/min, p < 0.05) but not in men (28.2 ± 7.8 vs. 28.0 ± 6.6 ml/kg/min, p > 0.10). Overall, women had a higher E/e' than men. Women without obesity had a similar E/e' to men with obesity (8.2 ± 1.8 vs. 8.4 ± 2.1, p > 0.10), and women with obesity had the highest E/e'. Among 5 risk factors (aging, obesity, elevated blood pressure, elevated heart rate, and elevated fasting glucose), obesity was a significant determinant of exercise intolerance in women but not men. Furthermore, obesity was associated with a greater risk of diastolic dysfunction in women than men (women, adjusted odds ratio 4.35 [95% confidence interval 2.44-7.74]; men, adjusted odds ratio 2.91 [95% confidence interval 1.42-5.95]).

CONCLUSION

Obesity had a more deleterious effect on exercise capacity and diastolic function in women than men, even in a healthy cohort. These subclinical changes might contribute to the development of a female predominance among HFpEF patients, particularly among individuals with obesity.

The GLP-1 Receptor Agonist Liraglutide Increases Myocardial Glucose Oxidation Rates via Indirect Mechanisms and Mitigates Experimental Diabetic Cardiomyopathy

BACKGROUND

Type 2 diabetes (T2D) increases risk for cardiovascular disease. Of interest, liraglutide, a therapy for T2D that activates the glucagon-like peptide-1 receptor to augment insulin secretion, reduces cardiovascular-related death in people with T2D, though it remains unknown how liraglutide produces these actions. Notably, the glucagon-like peptide-1 receptor is not expressed in ventricular cardiac myocytes, making it likely that ventricular myocardium-independent actions are involved. We hypothesized that augmented insulin secretion may explain how liraglutide indirectly mediates cardioprotection, which thereby increases myocardial glucose oxidation.

METHODS

C57BL/6J male mice were fed either a low-fat diet (lean) or were subjected to experimental T2D and treated with either saline or liraglutide 3× over a 24-hour period. Mice were subsequently euthanized and had their hearts perfused in the working mode to assess energy metabolism. A separate cohort of mice with T2D were treated with either vehicle control or liraglutide for 2 weeks for the assessment of cardiac function via ultrasound echocardiography.

RESULTS

Treatment of lean mice with liraglutide increased myocardial glucose oxidation without affecting glycolysis. Conversely, direct treatment of the isolated working heart with liraglutide had no effect on glucose oxidation. These findings were recapitulated in mice with T2D and associated with increased circulating insulin levels. Furthermore, liraglutide treatment alleviated diastolic dysfunction in mice with T2D, which was associated with enhanced pyruvate dehydrogenase activity, the rate-limiting enzyme of glucose oxidation.

CONCLUSIONS

Our data demonstrate that liraglutide augments myocardial glucose oxidation via indirect mechanisms, which may contribute to how liraglutide improves cardiovascular outcomes in people with T2D.

Impact of Obesity-Related Inflammation on Cardiac Metabolism and Function

This review focuses on the role of adipose tissue in obese individuals in the development of metabolic diseases, and their consequences for metabolic and functional derangements in the heart. The general idea is that the expansion of adipocytes during the development of obesity gives rise to unhealthy adipose tissue, characterized by low-grade inflammation and the release of proinflammatory adipokines and fatty acids (FAs). This condition, in turn, causes systemic inflammation and elevated FA concentrations in the circulation, which links obesity to several pathologies, including impaired insulin signaling in cardiac muscle and a subsequent shift in myocardial substrate oxidation in favor of FAs and reduced cardiac efficiency. This review also argues that efforts to prevent obesity-related cardiometabolic disease should focus on anti-obesogenic strategies to restore normal adipose tissue metabolism.

Sex-Specific Associations of Risks and Cardiac Structure and Function With Microalbumin/Creatinine Ratio in Diastolic Heart Failure

Background: Heart failure with preserved ejection fraction (HFpEF) affects women more frequently than men. However, data on sex-specific associations of adverse health outcomes and left ventricular structure and function and with microalbuminuria in patients with HFpEF are scarce. Methods: In 1,334 participants enrolled in the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) Trial, we estimated the sex-specific multivariable-adjusted risk and LV traits with urine microalbumin/creatine ratio (ACR), using Cox or linear regression. Results: In total, 604 (45.3%) were women. In multivariable-adjusted analyses, a doubling of ACR in both men and women was associated with higher posterior (+0.014 cm, p = 0.012/+0.012 cm, p = 0.033) wall thickness and left ventricular mass index (+2.55 mg/m2, p = 0.004/+2.45 mg/m2, p = 0.009), whereas was also associated with higher septal (+0.018 cm, p = 0.002) and left atrial volume index (+1.44 mL/m2, p = 0.001) in men. ACR was a key predictor of all-cause (HR, 1.11; p = 0.006) and cardiovascular (HR, 1.17; p = 0.002) death in women, whereas in men ACR was associated with HF hospitalization (HR, 1.23; p < 0.001), any hospitalization (HR, 1.06; p = 0.006), and myocardial infarction (HR, 1.19; p = 0.017). The interactions of sex with ACR were significant for hospitalization for heart failure and any hospitalization (p ≤ 0.034). Conclusions: Outcomes and cardiac structure and function in patients with HFpEF appear to be influenced by ACR that vary according to sex. In men, ACR was significant associated with LV diastolic function, hospitalization, and myocardial infarction, whereas in women was associated with mortality.

Females have higher myocardial perfusion, blood volume and extracellular volume compared to males - an adenosine stress cardiovascular magnetic resonance study

Knowledge on sex differences in myocardial perfusion, blood volume (MBV), and extracellular volume (ECV) in healthy individuals is scarce and conflicting. Therefore, this was investigated quantitatively by cardiovascular magnetic resonance (CMR). Healthy volunteers (n = 41, 51% female) underwent CMR at 1.5 T. Quantitative MBV [%] and perfusion [ml/min/g] maps were acquired during adenosine stress and at rest following an intravenous contrast bolus (0.05 mmol/kg, gadobutrol). Native T1 maps were acquired before and during adenosine stress, and after contrast (0.2 mmol/kg) at rest and during adenosine stress, rendering rest and stress ECV maps. Compared to males, females had higher perfusion, ECV, and MBV at stress, and perfusion and ECV at rest (p < 0.01 for all). Multivariate linear regression revealed that sex and MBV were associated with perfusion (sex beta −0.31, p = 0.03; MBV beta −0.37, p = 0.01, model R² = 0.29, p < 0.01) while sex and hematocrit were associated with ECV (sex beta −0.33, p = 0.03; hematocrit beta −0.48, p < 0.01, model R² = 0.54, p < 0.001). Myocardial perfusion, MBV, and ECV are higher in female healthy volunteers compared to males. Sex is an independent contributor to perfusion and ECV, beyond other physiological factors that differ between the sexes. These findings provide mechanistic insight into sex differences in myocardial physiology.

Gender-specific association between body mass index and all-cause mortality in patients with atrial fibrillation

Background

Elevated body mass index (BMI) is related with reduced mortality in various cardiovascular diseases.

Hypothesis

Gender‐specific association between BMI and mortality exists in atrial fibrillation (AF).

Methods

In this multicenter observational study with a mean follow‐up of 1 year, a total of 1991 AF patients were enrolled and divided into two groups based on the gender. The primary endpoint was all‐cause mortality while the secondary endpoints were defined as cardiovascular mortality, stroke, and major adverse events during 1‐year follow‐up. Cox regression was performed to identify the association between BMI and clinical outcomes according to gender.

Results

Female patients with AF tended to be older (P = .027) and thinner (P < .001) than male patients with AF. They were more likely to have heart failure, hyperthyroidism, and valvular AF (all P < .05), but less likely to have coronary artery disease and prior myocardial infarction (all P < .01). Multivariate analysis revealed that overweight (HR(95%CI): 0.55(0.41‐0.75), P < .001) and obese patients (HR(95%CI): 0.56(0.34‐0.94), P = .028) were associated with significant lower all‐cause mortality compared with normal weight patients for the entire cohort. Similar association between elevated BMI and reduced all‐cause mortality were only identified in female patients with AF (overweight vs normal weight: HR(95%CI): 0.43(0.27‐0.70); obesity vs normal weight: HR(95%CI): 0.46(0.22‐0.97)), but not in male patients with AF.

Conclusion

This study indicates that overweight and obesity were related with improved survival in patients with AF. The association between elevated BMI and reduced mortality was dependent on gender, which was only significant in female patients, rather than male patients.

Myocardium Metabolism in Physiological and Pathophysiological States: Implications of Epicardial Adipose Tissue and Potential Therapeutic Targets

The main energy substrate of adult cardiomyocytes for their contractility are the fatty acids. Its metabolism generates high ATP levels at the expense of high oxygen consumption in the mitochondria. Under low oxygen supply, they can get energy from other substrates, mainly glucose, lactate, ketone bodies, etc., but the mitochondrial dysfunction, in pathological conditions, reduces the oxidative metabolism. In consequence, fatty acids are stored into epicardial fat and its accumulation provokes inflammation, insulin resistance, and oxidative stress, which enhance the myocardium dysfunction. Some therapies focused on improvement the fatty acids entry into mitochondria have failed to demonstrate benefits on cardiovascular disorders. Oppositely, those therapies with effects on epicardial fat volume and inflammation might improve the oxidative metabolism of myocardium and might reduce the cardiovascular disease progression. This review aims at explain (a) the energy substrate adaptation of myocardium in physiological conditions, (b) the reduction of oxidative metabolism in pathological conditions and consequences on epicardial fat accumulation and insulin resistance, and (c) the reduction of cardiovascular outcomes after regulation by some therapies.

Waist circumference is associated with major adverse cardiovascular events in male but not female patients with type-2 diabetes mellitus

BACKGROUND

Although studies have shown that waist circumference (WC) is positively associated with an increased risk of cardiovascular diseases among the normal population, few studies have investigated WC in patients with type-2 diabetes mellitus (T2DM).

METHODS

This was a post hoc analysis of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study. The Cox proportional hazards models was used to investigate the relationship between WC and major adverse cardiovascular events (MACEs) in T2DM patients with cardiovascular disease (CVD) or high risk factors of CVD.

RESULTS

A total of 10,251 T2DM patients (6299 men [61.4%], 3952 women [38.6%]) were included in our analysis. The mean age was 64.0 ± 7.53 years. After a mean follow-up at 9.2 ± 2.4 years later, 1804 patients (event rate of 23 per 1000 person-years) had developed MACEs. MACEs rates in men and women were 18.0 and 26.0 events per 1000 person-years, respectively. After multivariable adjustment, each increase in WC of 1 SD increased the risk of MACEs (HR: 1.10, 95% CI 1.04-1.17; P < 0.01) in men, with a non-significant increase in MACEs (HR: 1.04, 95% CI 0.95-1.13; P = 0.40) in women. Compared with those in the first quartile of WC, male patients in the fourth quartile of WC had a hazard ratio (HR) of 1.24 (95% CI 1.05-1.46) for MACEs; female patients in the fourth quartile of WC had an HR of 1.22 (95% CI 0.96-1.56) for MACEs.

CONCLUSIONS

Higher WC is associated with increased risks of MACEs in male but not female T2DM patients. Trial registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000620).

Dietary Restrictions and Nutrition in the Prevention and Treatment of Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of death in many developed countries and remains one of the major diseases strongly affected by the diet. Nutrition can affect CVD directly by contributing to the accumulation of vascular plaques and also indirectly by regulating the rate of aging. This review summarizes research on nutrition and CVD incidence based on a multipillar system that includes basic research focused on aging, epidemiological studies, clinical studies, and studies of centenarians. The relevant research linking nutrition and CVD with focus on macronutrients and aging will be highlighted. We will review some of the most relevant studies on nutrition and CVD treatment, also focusing on interventions known to delay aging. We will discuss both everyday dietary compositions, as well as intermittent and periodic fasting interventions with the potential to prevent and treat CVD.

Sex Differences in Cardiovascular Pathophysiology: Why Women Are Overrepresented in Heart Failure With Preserved Ejection Fraction

Consistent epidemiological data demonstrate that patients with heart failure with preserved ejection fraction (HFpEF) are more likely to be women than men. Exploring mechanisms behind this sex difference in heart failure epidemiology may enrich the understanding of underlying HFpEF pathophysiology and phenotypes, with the ultimate goal of identifying therapeutic approaches for the broader HFpEF population. In this review we evaluate the influence of sex on the key domains of cardiac structure and function, the systemic and pulmonary circulation, as well as extracardiac factors and comorbidities that may explain the predisposition of women to HFpEF. We highlight the potential role of factors exclusive to or more prevalent in women such as pregnancy, preeclampsia, and iron deficiency. Finally, we discuss existing controversies and gaps in knowledge, as well as the clinical importance of known sex differences in the context of the potential need for sex-specific diagnostic criteria, improved risk stratification models, and targeted therapies.

Body mass index and outcomes of cardiac resynchronization with implantable cardioverter-defibrillator therapy in older patients with heart failure

AIMS

To assess the association of body mass index (BMI) with heart failure (HF) outcomes after cardiac resynchronization therapy with defibrillator (CRT-D) implantation.

METHODS AND RESULTS

Medicare beneficiaries with HF aged ≥ 65 years (n = 18 922) undergoing first-time CRT-D from the National Cardiovascular Data Registry (NCDR) Implantable Cardioverter-Defibrillator Registry between 2010 and 2013, were followed for 3 years post-implantation. Survival curves and covariate adjusted hazard ratio (aHR) or odds ratio were used to assess the risks for death, readmission, and device-related complications by BMI status. Of 18 922 HF patients receiving CRT-D, 5265 (27.8%) were normal weight, 6896 (37%) were overweight, 6318 (33.4%) were obese, and 353 (1.8%) were underweight. Compared to those of normal weight (BMI 18.5-24.9 kg/m² ), underweight patients had a higher 3-year post-device implantation risk of death [aHR: 1.34 (95% confidence interval 1.09-1.65); P < 0.001] and of readmission [sub-aHR: 1.25 (1.09-1.42); P < 0.001]. The corresponding 3-year aHRs for death were 0.83 (0.77-0.89) for overweight, 0.74 (0.67-0.82) for obesity class I (BMI 30-34.9 kg/m² ), 0.78 (0.68-0.90) for obesity class II (BMI 35-39.9 kg/m² ), and 0.75 (0.60-0.93) for obesity class III (BMI ≥ 40 kg/m² , P for all categories < 0.001). Individuals with class III obesity had a higher risk of readmission [sub-aHR: 1.17 (1.06-1.30)]. There were no differences in rates of device-related complications within 90 days across BMI categories.

CONCLUSION

Most elderly patients with HF receiving CRT-D were overweight or obese. While being underweight was associated with greater risks of death and hospitalization, overweight and obese patients were at lower risk of death after CRT-D.

Skeletal muscle mass in acute coronary syndrome prognosis: Gender-based analysis from Hellenic Heart Failure cohort

BACKGROUND AND AIMS

Predictive and prognostic ability of muscle mass in CVD settings is increasingly discussed. The gender-specific effect of skeletal muscle mass index (SMI) on 10-year recurrent fatal/non fatal cardiovascular disease (CVD) event of acute coronary syndrome (ACS) patients was evaluated.

METHODS AND RESULTS

In 2006-2009, n = 1000 consecutive patients (n = 222 women), hospitalized at the First Cardiology Clinic of Athens with ACS diagnosis and with symptoms and left ventricular function indicative of heart failure were selected. SMI was created to reflect skeletal muscle mass through appendicular skeletal muscle mass (indirectly calculated through population formulas) divided by body mass index (BMI). In the 10-year follow-up (2016), 55% of ACS patients experienced recurrent fatal/non fatal CVD events (53% in women vs.62% in men, p = 0.04). Patients in the 2nd SMI tertile (mostly overweight) had 10% lower risk for CVD recurrence (women:men rate ratio = 0.87) over their counterparts in the 1st (mostly normalweight) and 3rd tertile (mostly obese). Multivariate analysis revealed that ACS patients in the 2nd SMI tertile presented 46% and 85% lower CVD event risk over their counterparts in the 1st tertile (Hazard Ratio (HR) = 0.54, 95% Confidence Interval (95% CI) 0.30, 0.96, p = 0.002) and 3rd tertile (HR = 1.85, 95%CI 1.05, 2.94, p = 0.03). Gender-based analysis revealed that this trend remained significant only in women. Inflammatory markers had strong confounding effect.

CONCLUSION

A U-shape association between SMI and 10-year CVD event especially in women was highlighted. This work reveals gender-specific remarks for "obesity-lean paradox" in secondary prevention, implying that high muscle mass accompanied by obesity and excess adiposity may not guarantee better prognosis.

Sex differences in the 1H NMR metabolic profile of serum in cardiovascular risk patients

Personalized diagnosis and risk stratification of cardiovascular diseases would allow optimizing therapeutic strategies and lifestyle changes. Metabolomics is a promising technique for personalized diagnosis and prognosis; however, various physiological parameters, including sex, influence the metabolic profile thus hampering its translation to the clinic. Knowledge of the variation in the metabolic profile associated with sex would facilitate metabolomic translation to the clinic. The objective of the present work was to investigate the possible differences in the metabolic ¹H NMR profile associated to sex beyond lipoproteins. ¹H NMR spectra from whole serum and methanol deproteinized samples from 39 patients (22 males, 17 females) between 55–70 years old with suspected coronary artery disease that underwent a stress test that was considered negative where included. Deproteinized serum could be used to differentiate sex based on higher levels of lactate and glucose in women. Lipoprotein region was the most variable area of the spectra between individuals, but spectra of whole serum were able to differentiate sex based on lipoproteins. There are sex-related differences in the ¹H NMR metabolic profile of individuals with suspected cardiovascular disease beyond lipoproteins. These findings may help the translation of metabolomics to the clinic.

Combination GLP-1 and Insulin Treatment Fails to Alter Myocardial Fuel Selection vs. Insulin Alone in Type 2 Diabetes

CONTEXT

It is unclear if effects of glucagon-like peptide-1 (GLP-1) and clinically available GLP-1 agonists on the heart occur at clinical doses in humans, possibly contributing to reduced cardiovascular disease risk.

OBJECTIVE

To determine whether liraglutide, at clinical dosing, augments myocardial glucose uptake (MGU) alone or combined with insulin compared with insulin alone in metformin-treated type 2 diabetes mellitus (T2D).

DESIGN

In a randomized clinical trial of patients with T2D treated with metformin plus oral agents or basal insulin, myocardial fuel use was compared after 3 months of treatment with insulin detemir, liraglutide, or combination detemir plus liraglutide added to background metformin.

MAIN OUTCOME MEASURES

Myocardial blood flow (MBF), fuel selection, and rates of fuel use were evaluated using positron emission tomography, powered to demonstrate large effects.

RESULTS

MBF was greater in the insulin-treated groups [median (25th, 75th percentile): detemir, 0.64 mL/g/min (0.50, 0.69); liraglutide, 0.52 mL/g/min (0.46, 0.58); detemir plus liraglutide, 0.75 mL/g/min (0.55, 0.77); P = 0.035 comparing three groups, P = 0.01 comparing detemir groups to liraglutide alone]. There were no evident differences among groups in MGU [detemir, 0.040 µmol/g/min (0.013, 0.049); liraglutide, 0.055 µmol/g/min (0.019, 0.105); detemir plus liraglutide, 0.037 µmol/g/min (0.009, 0.046); P = 0.68 comparing three groups]. There were no treatment-group differences in measures of myocardial fatty acid uptake or handling, and no differences in total oxidation rate.

CONCLUSION

These observations argue against large effects of GLP-1 agonists on myocardial fuel metabolism as mediators of beneficial treatment effects on myocardial function and ischemia protection.

Higher plasma leptin levels are associated with reduced left ventricular mass and left ventricular diastolic stiffness in black women: insights from the Genetic Epidemiology Network of Arteriopathy (GENOA) study

Our previous experimental animal data suggest a beneficial effect of leptin on LV structure and function. We hypothesized that leptin levels are associated with lower LV mass and myocardial stiffness which are important risk factors for the development of heart failure with preserved ejection fraction (HFpEF). We evaluated 1172 blacks, in which the prevalence of HFpEF is quite high, with preserved LV ejection fraction (EF > 50%) from the Genetic Epidemiology Network of Arteriopathy Study (mean age 62.9 years, 72% women), a community-based study to identify genes influencing blood pressure and target organ damage due to hypertension. Associations between leptin levels and indices of LV structure and function were evaluated using generalized estimating equations accounting for clustering in siblings. LV myocardial stiffness was evaluated using diastolic wall strain (DWS) measured by echocardiography. Analyses were stratified by sex because leptin levels were three times higher in women than men (p < 0.001). After adjustment for confounders, higher leptin levels were associated with lower LV mass (coefficient for 1 s.d. increase of leptin level: -5.825 g, 95% CI: -9.755 to -1.895 g, P = 0.004) and higher DWS (lower LV stiffness) (coefficient for 1 s.d. increase of leptin level: 0.009, 95% CI: 0.002-0.015, P = 0.007) in women. There were no statistically significant associations in men. In women, there were interactions between leptin levels and body mass index quartiles on LV mass and stiffness (p < 0.05 for both). Higher leptin levels were associated with lower LV mass and stiffness in obese but not lean black women.

Sex differences in murine myocardium are not exclusively regulated by gonadal hormones

We investigated sex differences in cardiac protein patterns of intact and castrated mice using proteomics and 1D and 2D immunoblotting. To exclude differences concerning developmental aspects gonadectomy was conducted in mature mice at the age of three months. The main sex-related regulation in the protein pattern of the myocardium occurred for proteins involved in metabolic processes whereas only few proteins involved in other pathways underwent a regulation. Many regulated proteins (2/3) displayed a characteristic V form, which means that these proteins are up- or down-regulated in sexually mature compared to young mice and are back-regulated after castration, emphasizing a direct regulation by gonadal hormones. Several other spots (1/3) showed the same male/female regulation or a drastic increase in male/female spot intensity ratio after castration, suggesting either a regulation independent of sex hormones or a removal of an inhibiting feedback mechanism by gonadectomy. Technically, we found that it cannot be expected that a single spot contains only one protein species and that one protein is present in only one spot. We thus propose for proteomic investigations to identify/quantify all spots of a 2-DE pattern to obtain information about protein speciation and its potential importance for function and pathology.

BIOLOGICAL SIGNIFICANCE

Sex related differences in cardiovascular disease, including risk factors, disease manifestation and outcomes, are far from being well understood, and improved biological understanding of these differences in the healthy myocardium is of great importance. We investigated sex related changes of myocardial protein pattern in intact and castrated mice at different ages and found metabolic proteins to be highly regulated, some of which independently from gonadal hormones.

Gender-specific contribution of cardiometabolic index and lipid accumulation product to left ventricular geometry change in general population of rural China

Background

Despite current interest in the unfavorable impact of cardiometabolic index (CMI) and lipid accumulation product (LAP) on diabetes and cardiovascular risk, information regarding the relation of CMI and LAP to left ventricular (LV) geometry has not been specifically addressed. We aimed to examine the hypothesis: (1) CMI and LAP represent an independent determinant of LV remodeling in general population of rural China; (2) there are gender differences in obesity-related alterations in terms of LV morphology.

Methods

The sample for this cross-sectional analysis included 11,258 participants (mean age 53.9 years; 54.0% females) who underwent assessment of basic metabolic and anthropometric parameters in rural areas of northeast China. Comprehensive echocardiography-defined LV geometric pattern was determined according to left ventricular mass index and relative wall thickness.

Results

The prevalence rate of eccentric and concentric LV hypertrophy (LVH) presented a proportional increase with elevated quartiles of CMI and LAP in a dose-response manner (all P < 0.005). When CMI and LAP were entered as a continuous variable in multivariable adjusted model, we observed the independent effect of 1 SD increment in CMI and LAP with the probability of eccentric and concentric LVH, while this relationship was more pronounced in females than in males. Likewise, the odds ratio comparing the top versus bottom quartiles of CMI were 2.105 (95%CI:1.600–2.768) for eccentric LVH and 2.236 (95%CI:1.419–3.522) for concentric LVH in females. Males in the highest CMI quartile exhibited a nearly doubled (OR:1.724, 95%CI:1.287–2.311) and 1.523-fold (95%CI:1.003–2.313) greater risk of eccentric and concentric LVH, respectively. Increasing LAP entailed a higher possibility of eccentric LVH by a factor of 3.552 and 1.768 in females and males, respectively. In contrast to females, where LAP fourth quartile and concentric LVH were positively associated (OR:2.544, 95%CI:1.537–4.209), higher LAP did not correlate with concentric LVH in males (OR:1.234, 95%CI:0.824–1.849).

Conclusions

CMI and LAP give rise to a new paradigm of accounting for gender difference in obesity-related abnormal LV geometry, an effect that was substantially greater in females. These two indices, acting in concert, may also be advantageous prognostically for refining cardiovascular risk stratification in individuals with LV remodeling.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0798-0) contains supplementary material, which is available to authorized users.