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Objective: To explore the cardiac structural and functional changes in obstructive sleep apnea-hypopnea syndrome (OSAHS) patients with heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF). Methods: This retrospective study included 336 OSAHS patients with HFpEF. They were divided into Groups A (without an AF history and no AF episodes during cardiac color ultrasound examination), B (an AF history but no AF episodes), and C (an AF history and AF episodes). They all received cardiac color ultrasound examinations. Cardiac structural and functional changes in ultrasonic cardiograms were compared between the three groups. Results: Compared with Groups A and B, Group C showed increased left atrial diameter (LAD), left atrial volume (LAV), right ventricular diameter at end-diastole (RV-D1), right ventricular diameter at end-systole (RV-D2), right ventricular outflow tract diameter (RVOT2), right atrial diameter at end-diastole (RA-D1), right atrial diameter at end-systole (RA-D2), and right atrial area (RAA) (p < 0.05). Compared with Group A, Group C showed decreased fractional shortening (FS), left ventricular ejection fraction (LVEF), deceleration time (DT), isovolumic relaxation time (IVRT), E/E' ratio, and peak filling velocity (FPV), as well as increased E and E' (p < 0.01). Compared with Group B, Group C showed decreased FS and increased E and FPV (p < 0.01). Conclusion: In OSAHS patients with HFpEF and AF, cardiac remodeling and AF incidence are increased with the severity of OSAHS. OSAHS patients with HFpEF combined with AF have a significantly higher abnormality rate in right heart structural indices rather than left heart, mainly in the right atrium. [ABSTRACT FROM AUTHOR]

Aims: Lower limb amputee veterans are at high risk of cardiovascular disease due to physical problems and depression after the accident caused by amputation. Aerobic and resistance training are effective interventions in improving heart structure and function. The purpose of this study is to compare the effect of 12 weeks of aerobic and combined upper body training on structural and functional heart indices of lower limb amputation veterans. Materials & Methods: In this semi-experimental study, 45 lower limb amputees were randomly divided into 3 groups of aerobic training, combined training and control. The training groups received three sessions every week for 12 weeks and with the overload in the duration, volume and intensity of the desired intervention. Measurements of body composition BP, HR and structural and functional variables of the heart (EDD, ESD, LVEF, LVS, PWT, EF) before and after the intervention. One-way analysis of variance, Tukey's post hoc test and paired T test were used for intragroup and intergroup comparisons. Findings: Significant improvement was observed in BMI, HR, BP, EDD, ESD, LVEF and EF in the aerobic and combined exercise groups compared to the control group (P=0.05). Only ESD index, a significant improvement was observed in the combined exercise group compared to the exercise group (P=0.044). There was no significant change in the thickness of the LVS and PWT of the left ventricle (P=0.05). Conclusion: For lower limb amputation veterans, aerobic and combined exercises can have many benefits to prevent cardiovascular diseases by improving the structure and function of the heart. [ABSTRACT FROM AUTHOR]

Neural crest cells (NCCs) are a vertebrate-specific, multipotent stem cell population that have the ability to migrate and differentiate into various cell populations throughout the embryo during embryogenesis. The heart is a muscular and complex organ whose primary function is to pump blood and nutrients throughout the body. Mammalian hearts, such as those of humans, lose their regenerative ability shortly after birth. However, a few vertebrate species, such as zebrafish, have the ability to self-repair/regenerate after cardiac damage. Recent research has discovered the potential functional ability and contribution of cardiac NCCs to cardiac regeneration through the use of various vertebrate species and pluripotent stem cell-derived NCCs. Here, we review the neural crest's regenerative capacity in various tissues and organs, and in particular, we summarize the characteristics of cardiac NCCs between species and their roles in cardiac regeneration. We further discuss emerging and future work to determine the potential contributions of NCCs for disease treatment. [ABSTRACT FROM AUTHOR]

This study is to analyze the evaluation of CT imaging and clinical related factors of cardiac structure and function after coronary artery bypass grafting. 46 patients with coronary heart disease were included in the study. These patients underwent coronary artery bypass grafting. The improvement of EDV, ESV, SV and EF were observed by dual source CTA before and after operation, and these patients were divided into improved group and unimproved group. Gender, age, history of hypertension, history of diabetes, smoking rate, TC, TG, HDL-C, coronary stenosis and systolic wall thickening rate of lesion segments were compared between the two groups. The results showed that the proportion of diabetes and coronary artery stenosis in the EF unimproved group was higher than that in the improved group, but the ventricular wall thickening rate was lower than that in the improved group (P<0.05). The improvement of EF was negatively correlated with diabetes and coronary stenosis (P<0.05), and positively correlated with the systolic wall thickening rate of lesion segments (P<0.05), and the improvement of ESV was negatively correlated with TC and TG (P<0.05). Thus, the improvement of EF is related to diabetes, coronary artery stenosis and the systolic wall thickening rate of lesion segments. The improvement of ESV is related to TC and TG. [ABSTRACT FROM AUTHOR]

In this study we aimed to assess the effects of continuous formalin fixation on diffusion and relaxation metrics of the ex vivo porcine heart at 7 T. Magnetic resonance imaging was performed on eight piglet hearts using a 7 T whole body system. Hearts were measured fresh within 3 hours of cardiac arrest followed by immersion in 10% neutral buffered formalin. T2* and T2 were assessed using a gradient multi‐echo and multi‐echo spin echo sequence, respectively. A spin echo and a custom stimulated echo sequence were employed to assess diffusion time‐dependent changes in metrics of cardiac diffusion tensor imaging. SNR was determined for b = 0 images. Scans were performed for 5 mm thick apical, midcavity and basal slices (in‐plane resolution: 1 mm) and repeated 7, 15, 50, 100 and 200 days postfixation. Eigenvalues of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) decreased significantly (P < 0.05) following fixation. Relative to fresh hearts, FA values 7 and 200 days postfixation were 90% and 80%, while respective relative ADC values at those fixation stages were 78% and 92%. Statistical helix and sheetlet angle distributions as well as respective mean and median values showed no systematic influence of continuous formalin fixation. Similar to changes in the ADC, values for T2, T2* and SNR dropped initially postfixation. Respective relative values compared with fresh hearts at day 7 were 64%, 79% and 68%, whereas continuous fixation restored T2, T2* and SNR leading to relative values of 74%, 100%, and 81% at day 200, respectively. Relaxation parameters and diffusion metrics are significantly altered by continuous formalin fixation. The preservation of microstructure metrics following prolonged fixation is a key finding that may enable future studies of ventricular remodeling in cardiac pathologies. [ABSTRACT FROM AUTHOR]

Background: Empagliflozin (empa), a selective sodium–glucose cotransporter (SGLT)2 inhibitor, reduced cardiovascular mortality and hospitalization for heart failure in patients with type 2 diabetes at high cardiovascular risk independent of glycemic control. The cardiovascular protective effect of empa was evaluated in an experimental model of metabolic syndrome, the obese ZSF1 rat, and its' lean control. Methods: Lean and obese ZSF1 rats were either non-treated or treated with empa (30 mg/kg/day) for 6 weeks. Vascular reactivity was assessed using mesenteric artery rings, systolic blood pressure by tail-cuff sphygmomanometry, heart function and structural changes by echocardiography, and protein expression levels by Western blot analysis. Results: Empa treatment reduced blood glucose levels from 275 to 196 mg/dl in obese ZSF1 rats whereas normoglycemia (134 mg/dl) was present in control lean ZSF1 rats and was unaffected by empa. Obese ZSF1 rats showed increased systolic blood pressure, and blunted endothelium-dependent relaxations associated with the appearance of endothelium-dependent contractile responses (EDCFs) compared to control lean rats. These effects were prevented by the empa treatment. Obese ZSF1 rats showed increased weight of the heart and of the left ventricle volume without the presence of diastolic or systolic dysfunction, which were improved by the empa treatment. An increased expression level of senescence markers (p53, p21, p16), tissue factor, VCAM-1, SGLT1 and SGLT2 and a down-regulation of eNOS were observed in the aortic inner curvature compared to the outer one in the control lean rats, which were prevented by the empa treatment. In the obese ZSF1 rats, no such effects were observed. The empa treatment reduced the increased body weight and weight of lungs, spleen, liver and perirenal fat, hyperglycemia and the increased levels of total cholesterol and triglycerides in obese ZSF1 rats, and increased blood ketone levels and urinary glucose excretion in control lean and obese ZSF1 rats. Conclusion: Empa reduced glucose levels by 28% and improved both endothelial function and cardiac remodeling in the obese ZSF1 rat. Empa also reduced the increased expression level of senescence, and atherothrombotic markers at arterial sites at risk in the control lean, but not obese, ZSF1 rat. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND The average of multiple blood pressure (BP) readings (mean BP) independently predicts target organ damage (TOD). Observational studies have also shown an independent relationship between BP variability (BPV) and TOD, but there is limited longitudinal data. This study aimed to determine the effects of changes in mean BP levels compared with BPV on left ventricular mass index (LVMI) and aortic pulse wave velocity (aPWV). METHODS Mean BP levels (research-protocol clinic BP (clinic BP), 24-hour ambulatory BP, and 7-day home BP) and BPV were assessed in 286 patients with uncomplicated hypertension (mean age 64 ± 8 SD years, 53% women) over 12 months. Reading-to-reading BPV (from 24-hour ambulatory BP) and day-to-day BPV (from 7-day home BP) were assessed at baseline and 12 months, and visit-to-visit BPV (clinic BP) was assessed from 5 visits over 12 months. LVMI was measured by 3D echocardiography and aPWV with applanation tonometry. RESULTS The strongest predictors of the changes in LVMI (ΔLVMI) were the changes in mean 24-hour systolic BPs (SBPs) (P < 0.02). Similarly, the strongest predictors of the changes in aPWV (ΔaPWV) were the changes in mean 24-hour ambulatory SBPs (P < 0.01) and the changes in mean clinic SBP (P < 0.001). However, none of the changes in BPV were independently associated with ΔLVMI or ΔaPWV (P > 0.05 for all). CONCLUSIONS Changes in mean BP levels, but not BPV, were most relevant to changes in TOD in patients with uncomplicated hypertension. Thus, from this point of view, BPV appears to have limited clinical utility in this patient population. [ABSTRACT FROM AUTHOR]

Purpose Diffusion MRI requires acquisition of multiple diffusion-weighted images, resulting in long scan times. Here, we investigate combining compressed sensing and a fast imaging sequence to dramatically reduce acquisition times in cardiac diffusion MRI. Methods Fully sampled and prospectively undersampled diffusion tensor imaging data were acquired in five rat hearts at acceleration factors of between two and six using a fast spin echo (FSE) sequence. Images were reconstructed using a compressed sensing framework, enforcing sparsity by means of decomposition by adaptive dictionaries. A tensor was fit to the reconstructed images and fiber tractography was performed. Results Acceleration factors of up to six were achieved, with a modest increase in root mean square error of mean apparent diffusion coefficient (ADC), fractional anisotropy (FA), and helix angle. At an acceleration factor of six, mean values of ADC and FA were within 2.5% and 5% of the ground truth, respectively. Marginal differences were observed in the fiber tracts. Conclusion We developed a new k-space sampling strategy for acquiring prospectively undersampled diffusion-weighted data, and validated a novel compressed sensing reconstruction algorithm based on adaptive dictionaries. The k-space undersampling and FSE acquisition each reduced acquisition times by up to 6× and 8×, respectively, as compared to fully sampled spin echo imaging. Magn Reson Med 76:248-258, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine the influence of sodium fluoride (NaF) in different concentrations on morphological change, cell viability, cardiac arrest rate, and apoptosis in primary cardiomyocytes of neonatal rats. NaF at concentrations of 0, 2, 4, 8, and 16 mg/L was administered to cultured cardiomyocytes. The results showed that, NaF, in a concentration dependent-manner and even at the low concentration of 2 mg/L, changed the morphology of the cardiomyocytes, reduced cell viability, increased the cardiac arrest rate, and enhanced the levels of apoptosis. [ABSTRACT FROM AUTHOR]

Cardiomyocytes grow during heart maturation or disease-related cardiac remodeling. We present evidence that the intercalated disc (ID) is integral to both longitudinal and lateral growth: increases in width are accommodated by lateral extension of the plicate tread regions and increases in length by sarcomere insertion within the ID. At the margin between myofibril and the folded membrane of the ID lies a transitional junction through which the thin filaments from the last sarcomere run to the ID membrane and it has been suggested that this junction acts as a proto Z-disc for sarcomere addition. In support of this hypothesis, we have investigated the ultrastructure of the ID in mouse hearts from control and dilated cardiomyopathy (DCM) models, the MLP-null and a cardiac-specific β-catenin mutant, cΔex3, as well as in human left ventricle from normal and DCM samples. We find that the ID amplitude can vary tenfold from 0.2 μm up to a maximum of ~2 μm allowing gradual expansion during heart growth. At the greatest amplitude, equivalent to a sarcomere length, A-bands and thick filaments are found within the ID membrane loops together with a Z-disc, which develops at the transitional junction position. Here, also, the tops of the membrane folds, which are rich in αII spectrin, become enlarged and associated with junctional sarcoplasmic reticulum. Systematically larger ID amplitudes are found in DCM samples. Other morphological differences between mouse DCM and normal hearts suggest that sarcomere inclusion is compromised in the diseased hearts. [ABSTRACT FROM AUTHOR]

Mouse models are increasingly used to study the pathophysiology of myocardial infarction in vivo. In this area, MRI has become the gold standard imaging modality, because it combines high spatial and temporal resolution functional imaging with a large variety of methods to generate soft tissue contrast. In addition, (target-specific) MRI contrast agents can be employed to visualize different processes in the cascade of events following myocardial infarction. Here, the MRI sequence has a decisive role in the detection sensitivity of a contrast agent. However, a straightforward translation of clinically available protocols for human cardiac imaging to mice is not feasible, because of the small size of the mouse heart and its extremely high heart rate. This has stimulated intense research in the development of cardiac MRI protocols specifically tuned to the mouse with regard to timing parameters, acquisition strategies, and ECG- and respiratory-triggering methods to find an optimal trade-off between sensitivity, scan time, and image quality. In this review, a detailed analysis is given of the pros and cons of different mouse cardiac MR imaging methodologies and their application in contrast-enhanced MRI of myocardial infarction. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Despite the wide use of bisphenol A (BPA) in plastic and epoxy resin industries, its side effects have been a subject of controversy. Lycopene (a natural carotenoid) has a protective role in many cardiovascular diseases. This work aimed to study the biochemical and structural changes induced by BPA in the myocardium of adult rats and evaluate whether coadministration of lycopene could alter these effects.Twenty adult male albino rats were divided into four equal groups. Group I was the control. Group II received lycopene (4mg/kg body weight/day orally) for 8 weeks. Group III was given BPA (50mg/kg body weight/day orally) for 8 weeks. Group IV was given both BPA and lycopene in the same previous dose and for the same duration. At the end of the experiment, rats were anesthetized, and their hearts were taken and prepared for histological and biochemical studies. Area percentages of the collagen content and positive immune reaction for vimentin were morphometrically and statistically analyzed.Examination of group III revealed that some myocytes had a deeply acidophilic cytoplasm and were devoid of nuclei. Some myocytes appeared with pale vacuolated cytoplasm, and some had focal loss of myofibrils. Their sarcoplasm contained many distorted mitochondria and dilated T-tubules. Their nuclei were variable in shape. They were peripherally located, or deeply indented, or heterochromatic. Many interstitial cells, inflammatory cells, congested blood capillaries, and areas of edema were seen. A significant increase in collagen fibers and in the area percentage of positive immune reaction for vimentin compared with the control group was observed. Examination of group IV showed that the cardiac muscle cells had a normal architecture except for a few distorted muscle fibers and many congested blood capillaries. There was a significant decrease in the area percentage of positive immune reaction for vimentin in group IV compared with group III. The current study revealed significant increase in serum malondialdehyde, whereas tissue reduced glutathione and catalase showed significant decrease in group III compared with the control group. In contrast, in group IV, malondialdehyde showed significant decrease, and tissue reduced glutathione and catalase showed significant increase, compared with group III.Long-term exposure to BPA could induce structural and biochemical changes in rat cardiac muscle. This could be partially minimized by concomitant administration of lycopene. [ABSTRACT FROM AUTHOR]

Following fixation and MRI imaging a post-mortem human heart was sliced at the sagittal plane. Each anatomical section was then cut into smaller segments and each one was objected to classical histology process. The resulting microscopy slides were digitalized with a scanner. The histological section reconstruction was achieved using Adobe Photoshop CS2®. Using specific software, called FiberCad, the user can define and draw (with the assistance of optical microscope) those fibers that are parallel and those fibers that are vertical to the slides plane. To better align the histological 3D reconstruction, the software is equipped with an option that allows the user to make best possible fit between histological and MRI slices. We present the consequent sagittal sections of LV free wall (from epicardial to endocardial surface), whereby the clockwise rotation of the mean orientation of the fibers that are on the plane of sectioning is clearly evident. We present a post mortem analysis of the complete LV free wall of a human heart. [ABSTRACT FROM AUTHOR]

Copyright of Cardiologia Croatica is the property of Croatian Cardiac Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)