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Background: In patients with hypertrophic cardiomyopathy (HCM), impaired augmentation of stroke volume and diastolic dysfunction contribute to exercise intolerance. Systolic–diastolic (S‐D) coupling characterizes how systolic contraction of the left ventricle (LV) primes efficient elastic recoil during early diastole. Impaired S‐D coupling may contribute to the impaired cardiac response to exercise in patients with HCM. Methods: Patients with HCM (n = 25, age = 47 ± 9 years) and healthy adults (n = 115, age = 49 ± 10 years) underwent a cardiopulmonary exercise testing (CPET) and echocardiogram. S‐D coupling was defined as the ratio of LV longitudinal excursion of the mitral annulus during early diastole (EDexc) and systole (Sexc) and compared between groups. Peak oxygen uptake (peak V̇O2) (Douglas bags), cardiac index (C2H2 rebreathe), and stroke volume index (SVi) were assessed during CPET. Linear regression was performed between S‐D coupling and peak V̇O2, peak cardiac index, and peak SVi. Results: S‐D coupling was lower in HCM (Controls: 0.63 ± 0.08, HCM: 0.56 ± 0.10, p < 0.001). Peak V̇O2 and stroke volume reserve were lower in patients with HCM (Peak VO2 Controls: 28.5 ± 5.5, HCM: 23.7 ± 7.2 mL/kg/min, p < 0.001, SV reserve: Controls 39 ± 16, HCM 30 ± 18 mL, p = 0.008). In patients with HCM, S‐D coupling was associated with peak V̇O2 (r = 0.47, p = 0.018), peak cardiac index (r = 0.60, p = 0.002), and peak SVi (r = 0.63, p < 0.001). Conclusion: Systolic–diastolic coupling was impaired in patients with HCM and was associated with fitness and the cardiac response to exercise. Inefficient S‐D coupling may link insufficient stroke volume generation, diastolic dysfunction, and exercise intolerance in HCM. [ABSTRACT FROM AUTHOR]

Patients with hypertrophic cardiomyopathy (HCM) often have reduced exercise capacity, and it is unclear whether cardiovascular regulation during exercise is intact in these patients. We aimed to determine the relationship between cardiac output (Q̇c) and oxygen uptake (V̇o2), and stroke volume (SV) reserve in HCM compared with healthy participants and participants with left ventricular hypertrophy (LVH) but not HCM. Sixteen patients with HCM (48 ± 7 yr, 44% female), 16 participants with LVH (49 ± 5 yr, 44% female), and 61 healthy controls (CON: 52 ± 5 yr, 52% female) completed submaximal steady-state treadmill exercise followed by a maximal exercise test. V̇o2, Q̇c, SV, and arteriovenous oxygen difference were measured during rest and exercise, and Q̇c/V̇o2 slopes were constructed, The Q̇c/V̇o2 slope was blunted in HCM compared with CON and LVH [HCM 4.9 ± 0.7 vs. CON 5.5 ± 1.0 (P = 0.027) vs. LVH 6.0 ± 1.0 AU (P = 0.002)] and participants with HCM had a lower SV reserve (HCM 53 ± 33%, controls 83 ± 33%, LVH 82 ± 22%; HCM vs. controls P = 0.002; HCM vs. LVH P = 0.015). Despite a blunted Q̇c/V̇o2 slope, 75% of patients with HCM achieved ≥80% predicted V̇o2max by augmenting a-vo2 difference at maximal exercise (16.0 ± 0.8 mL/100 mL vs. 13.8 ± 2.7 mL/100 mL, P = 0.021). Patients with HCM do not appropriately match Q̇c to metabolic demand, primarily due to inadequate stroke volume augmentation. Despite this central limitation, many patients achieve normal exercise capacities by significantly increasing peripheral oxygen extraction. NEW & NOTEWORTHY Through state-of-the-art hemodynamic and oxygen uptake methodologies, this study found the cardiac output response to increasing metabolic demand is blunted among patients with hypertrophic cardiomyopathy (HCM), primarily due to a reduced stroke volume reserve. Many patients with HCM augment their peripheral oxygen extraction during maximal exercise to achieve normal exercise capacity and overcome ineffective matching of cardiac output. Peripheral adaptations that compensate for cardiac limitations may contribute to the heterogeneity of functional limitations observed within this patient population. [ABSTRACT FROM AUTHOR]

Background: Excess adipose tissue has been implicated in the pathogenesis of insulin resistance and atherosclerosis and is a key risk factor for blood pressure (BP) elevation. However, circulating levels of adiponectin, a protein produced by adipose tissue and widely implicated in the pathogenesis of insulin resistance and atherosclerosis, are inversely proportional to adiposity. The relationship between adiponectin and incident hypertension has not been determined in the general US population.Methods: Normotensive participants (n = 1233) enrolled in the Dallas Heart Study, a multiethnic, probability-based population sample of Dallas County adults were followed for median of 7 years. Retroperitoneal, intraperitoneal, visceral, and subcutaneous adipose tissue were measured at baseline by magnetic resonance imaging. Liver fat content was measured by 1 H-magnetic resonance spectroscopy. Relative risk regression was used to determine the association of adiponectin with incident hypertension after adjustment for age, race, sex, BMI, smoking, diabetes, baseline systolic BP, total cholesterol, and regional fat depot.Results: Of the 1233 study participants (median age 40 years, 40% black, and 56% women), 391 (32%) had developed hypertension over a median follow-up of 7 years. Adiponectin levels were associated with reduced risk of incident hypertension (RR 0.81, 95% CI [0.68-0.96]) in the fully adjusted model, which included liver fat. Similar results were observed after adjustment for subcutaneous or visceral fat depots when tested individually or simultaneously in the model.Conclusion: Our study suggested a protective role of adiponectin against incident hypertension independent of body fat distribution. [ABSTRACT FROM AUTHOR]

More than 1 in 10 US adolescents have prediabetes or diabetes, and elevated glycosylated haemoglobin (HbA1C) in youth is associated with increased risk of death before the age of 55 years. We conducted a prospective, cross-sectional study of 31,546 consecutive volunteer blood donors, 16–19 years of age, who donated blood during school blood drives between 1 September 2011 and 21 December 2012 in Texas. In the overall cohort, the prevalence of elevated HbA1C was 11.5%, including 11.0% in the prediabetes range (HbA1C 5.7%–6.4%) and 0.5% in the diabetes range (HbA1C ⩾ 6.5%). The prevalence of elevated HbA1C was higher in boys compared with girls (15.7% vs 7.9%, p < 0.001) and was especially high in racial/ethnic minorities (Blacks 32.7%, Asians 19.7%, Hispanics 13.1%) compared with Whites (8.0%, p < 0.001). There was a significant increase in total cholesterol and blood pressure across categories of increasing HbA1C in the overall cohort and stratified by sex and race/ethnicity. Blood donation programmes can serve as unique portals for health screening with potential for intervention in adolescents. [ABSTRACT FROM AUTHOR]

Objective: To determine whether increases in cardiac work lead to alterations in the plasma metabolome and whether such changes arise from the heart or peripheral organs. Background: There is growing evidence that the heart influences systemic metabolism through endocrine effects and affecting pathways involved in energy homeostasis. Methods: Nineteen patients referred for cardiac catheterization were enrolled. Peripheral and selective coronary sinus (CS) blood sampling was performed at serial timepoints following the initiation of pacing, and metabolite profiling was performed by liquid chromatography-mass spectrometry (LC-MS). Results: Pacing-stress resulted in a 225% increase in the median rate·pressure product from baseline. Increased myocardial work induced significant changes in the peripheral concentration of 43 of 125 metabolites assayed, including large changes in purine [adenosine (+99%, p = 0.006), ADP (+42%, p = 0.01), AMP (+79%, p = 0.004), GDP (+69%, p = 0.003), GMP (+58%, p = 0.01), IMP (+50%, p = 0.03), xanthine (+61%, p = 0.0006)], and several bile acid metabolites. The CS changes in metabolites qualitatively mirrored those in the peripheral blood in both timing and magnitude, suggesting the heart was not the major source of the metabolite release. Conclusions: Isolated increases in myocardial work can induce changes in the plasma metabolome, but these changes do not appear to be directly cardiac in origin. A number of these dynamic metabolites have known signaling functions. Our study provides additional evidence to a growing body of literature on metabolic ‘cross-talk’ between the heart and other organs. [ABSTRACT FROM AUTHOR]

Background: Aggregation of metabolic risk factors- i.e., elevated plasma triglyceride (TG), reduced high-density lipoprotein cholesterol (HDL-C), elevated blood pressure, and raised plasma glucose-convey increased risk for atherosclerotic cardiovascular disease and type 2 diabetes. Methods: This study was carried out to determine the association of waist girth, ethnicity, and gender with susceptibility for metabolic risk. Included were 1671 adult women (50.7% black) and 1339 men (46.5% black) enrolled in the Dallas Heart Study. Subjects were stratified into three categories by waist girth-low, intermediate, and high, corresponding to BMI ranges of <25 kg/m2, 25-29.9 kg/m2, and ≥30 kg/m2. Results: Risk factor prevalence rose progressively through each waist-girth category. However, even among those with high waist-girth, prevalence of three or more risk factors was less than 50%. Several differences among the ethnic groups were noted; for example, Hispanic men had a higher prevalence of elevated TG compared to whites; black men, on the other hand, had a lower frequency of high TG. There were also fewer black men with low HDL-C than in the other groups. Black and Hispanic men had a higher prevalence of elevated glucose and updated homeostasis model assessment of insulin resistance (HOMA2-IR) than whites. More black men had elevated blood pressure than other groups. These differences were less pronounced among ethnic groups of women. Conclusion: Although ethnic and gender differences in risk factor prevalence may exist, it is notable that the majority of subjects, even when obese, did not have elevated risk factors. This finding points to the need to focus largely on subjects with metabolic risk factors when implementing therapeutic interventions. [ABSTRACT FROM AUTHOR]

Objective: Visceral (VAT) and abdominal subcutaneous (SAT) adipose tissues contribute to obesity but may have different metabolic and atherosclerosis risk profiles. We sought to determine the associations of abdominal VAT and SAT mass with markers of cardiac and metabolic risk in a large, multiethnic, population-based cohort of obese adults. Design and Methods: Among obese participants in the Dallas Heart Study, we examined the cross-sectional associations of abdominal VAT and SAT mass, assessed by magnetic resonance imaging (MRI) and indexed to body surface area (BSA), with circulating biomarkers of insulin resistance, dyslipidemia, and inflammation ( n = 942); and with aortic plaque and liver fat by MRI and coronary calcium by computed tomography ( n = 1200). Associations of VAT/BSA and SAT/BSA were examined after adjustment for age, sex, race, menopause, and body mass index. Results: In multivariable models, VAT significantly associated with the homeostasis model assessment of insulin resistance (HOMA-IR), lower adiponectin, smaller LDL and HDL particle size, larger VLDL size, and increased LDL and VLDL particle number ( p < 0.001 for each). VAT also associated with prevalent diabetes, metabolic syndrome, hepatic steatosis, and aortic plaque ( p < 0.001 for each). VAT independently associated with C-reactive protein but not with any other inflammatory biomarkers tested. In contrast, SAT associated with leptin and inflammatory biomarkers, but not with dyslipidemia or atherosclerosis. Associations between SAT and HOMA-IR were significant in univariable analyses but attenuated after multivariable adjustment. Conclusion: VAT associated with an adverse metabolic, dyslipidemic, and atherogenic obesity phenotype. In contrast, SAT demonstrated a more benign phenotype, characterized by modest associations with inflammatory biomarkers and leptin, but no independent association with dyslipidemia, insulin resistance, or atherosclerosis in obese individuals. These findings suggest that abdominal fat distribution defines distinct obesity sub-phenotypes with heterogeneous metabolic and atherosclerosis risk. [ABSTRACT FROM AUTHOR]

This study examines intercorrelations among waist circumference (WC), intraperitoneal fat (IPF), and subcutaneous abdominal fat (SAF) in ethnically diverseDallasHeart Study consisting of 1538 women and 1212men (50% Black). Correlations between fat depots and triglyceride or HOMA2-IR, biomarkers of metabolic syndrome, are also reported. Total abdominal fat (TAF), ASF, and IPF masses were measured by magnetic resonance imaging.The highest correlations withWC according to ethnicity and gender were noted for TAF (R2 = 0.81 - 0.88) with progressively lower correlations with ASF (0.65 - 0.82) and IPF (0.29 - 0.85).The percentage of IPF relative to TAF was not significantly correlated withWC. For allWC categories, higher IPF/ASF ratios were associated with higher triglyceride levels. In contrast, differences in ratios had little or no association with HOMA2-IR. However, when all data were pooled, IPF was positively correlated with both triglyceride (r = 0.358 (men) and 0.363 (women)) and HOMA2-IR (r = 0.480 (men) and 0.517 (women)); after adjustment for ASF, IPF was still correlated with triglyceride (r = 0.353 (men) and 0.348 (women)) andHOMA2-IR (r = 0.290 (men) and 0.221 (women)).WC measures TAF reliably, but its association with IPF depends on IPF/ASF ratios that vary by gender and ethnicity. [ABSTRACT FROM AUTHOR]

The article discusses the long term outcome of bariatric surgery. It reports that sustained weight loss, lower incidences of cardiovascular diseases, diabetes and cancer are some of the benefits from bariatric surgery. The study was conducted in obese controlled Swedish subjects. During a follow up of 20 years following the bariatric procedure, the surgery patients used a 54 mean cumulative hospital days against the 40 days of the control group at a confidence interval (C.I.) of 95 percent. However, the study highlights that the drug costs from the seventh year were lower for patients who underwent the surgery than control patients.

Aim The presence of septal hypertrophy in hypertrophic cardiomyopathy (HCM) is common. To date, there has been no accepted classification of septal morphology in HCM. Furthermore, the possible relationship between septal morphology and clinical features of HCM is undefined. Methods and results Seventy-five consecutive adult patients with HCM were enrolled. Septal morphologies were retrospectively categorized into one of four patterns of hypertrophy based on transthoracic echocardiography. Left ventricular diastolic function by Doppler echocardiography and late gadolinium enhancement (LGE) by magnetic resonance imaging were assessed in all patients. Patients were followed for a mean of 45 ± 32 months. Catenoid septum was the most common morphologic subtype (46 of 75, 61%), followed by simple sigmoid (22 of 75, 29%), neutral (4 of 75, 5%), and apical (3 of 75, 4%). Inter-observer reproducibility of septal classifications was high (κ = 0.95). Patients with the catenoid subtype presented at a younger age, had worse diastolic function, and high rates of LGE. The presence of catenoid septal morphology was independently associated with LGE in multivariable logistic regression analysis. Implantable cardioverter-defibrillator implantation for prevention of sudden cardiac death occurred only in patients with this septal morphology. Conclusion We propose a simple, reproducible classification system of patterns of septal hypertrophy in HCM. These patterns of hypertrophy are associated with significant differences in clinical, haemodynamic, and myocardial characteristics. Further studies are needed to evaluate the relationship between septal morphology and outcome or response to therapies in HCM. [ABSTRACT FROM AUTHOR]