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Background Primates represent a unique object for biomedical research, in particular in the field of physiology and pathology of the cardiovascular system. Echocardiography is the most important non-invasive method for the intravital study of the heart structure and function, intracardiac and systemic haemodynamics. The available data on reference values of echocardiographic parameters in primates are limited. Methods We determined and described 29 structural and functional parameters in echocardiographic examination using B-mode (two-dimensional scanning), M-mode (one-dimensional scanning) and in various Doppler modes together with blood pressure in 17 male cynomolgus macaques with an average age of 5.7 ± 0.6 years. We compared available literature data on reference values of echocardiography in this species. Results and conclusions Echocardiographic values in cynomolgus macaques depend on age, sex composition and the anaesthesia method. There is lack of presentation in the published studies of complete list of parameters that can be obtained by echocardiographic examination.

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.

This paper is the outcome of the fourth UC Davis Systems Approach to Understanding Cardiac Excitation-Contraction Coupling and Arrhythmias Symposium, a biannual event that aims to bring together leading experts in subfields of cardiovascular biomedicine to focus on topics of importance to the field. The theme of the 2016 symposium was 'K+ Channels and Regulation'. Experts in the field contributed their experimental and mathematical modelling perspectives and discussed emerging questions, controversies and challenges on the topic of cardiac K+ channels. This paper summarizes the topics of formal presentations and informal discussions from the symposium on the structural basis of voltage-gated K+ channel function, as well as the mechanisms involved in regulation of K+ channel gating, expression and membrane localization. Given the critical role for K+ channels in determining the rate of cardiac repolarization, it is hardly surprising that essentially every aspect of K+ channel function is exquisitely regulated in cardiac myocytes. This regulation is complex and highly interrelated to other aspects of myocardial function. K+ channel regulatory mechanisms alter, and are altered by, physiological challenges, pathophysiological conditions, and pharmacological agents. An accompanying paper focuses on the integrative role of K+ channels in cardiac electrophysiology, i.e. how K+ currents shape the cardiac action potential, and how their dysfunction can lead to arrhythmias, and discusses K+ channel-based therapeutics. A fundamental understanding of K+ channel regulatory mechanisms and disease processes is fundamental to reveal new targets for human therapy.

Accurate age- and sex-related normal reference values of ventricular structure and function are important to determine the level of dysfunction in patients. The aim of this study therefore was to document normal age range sex-related measurements of LV structural and functional measurements to serve such purpose.We evaluated left ventricular structure and function in 293 healthy subjects between 20 and 90 years with equally distributed gender. Doppler echocardiography was used including measure of both systolic and diastolic functions.Due to systolic LV function, only long axis function correlated with age (r = 0·55, P0·01) and the correlation was stronger in females. Concerning diastolic function, there was a strong age correlation in all parameters used (r = 0·40-0·74, P0·001). Due to LV structural changes over age, females showed a larger reduction in end-diastolic volumes, but no or trivial difference in wall thickness after the age of 60 years.Age is associated with significant normal changes in left ventricular structure and function, which should be considered when deciding on normality. These changes are related to systemic arterial changes as well as body stature, thus reflecting overall body ageing process. Furthermore, normal cardiac ageing in females might partly explain the higher prevalence of heart failure with preserved ejection in females.

Background Chronic inflammation is linked to age-associated declines in heart structure and function that contribute to increased risks for cardiovascular mortality and frailty, a state of high vul...

Undernutrition during development increases the risk for adult cardiovascular disease. To determine if PUN alters heart structure function, and maximal exercise capacity in adulthood, newborn control mouse pups were fostered to dams fed a control (CON; 20% protein) or a protein-restricted diet (PUN; 8% protein; n=7-10 litters/treatment). At 21 d (PN21) pups were fed the CON diet ad lib. At PN70 a maximal treadmill test was performed to determine VO2peak; maximal vertical work was calculated for the final 30 sec. At PN80 cardiac function was evaluated by echocardiography. VO2peak was the same in CON and PUN mice and higher in males than females (249 + 9 and 169 + 6 ml/hr, respectively, P