Ischemic tolerance and cardiac repair in the spiny mouse (Acomys)

Ischemic heart disease and by extension myocardial infarction is the primary cause of death worldwide, warranting regenerative therapies to restore heart function. Current models of natural heart regeneration are restricted in that they are not of adult mammalian origin, precluding the study of class-specific traits that have emerged throughout evolution, and reducing translatability of research findings to humans. Here, we present the spiny mouse (Acomys spp.), a murid rodent that exhibits bona fide regeneration of the back skin and ear pinna, as a model to study heart repair. By comparing them to ordinary mice (Mus musculus), we show that the acute injury response in spiny mice is similar, but with an associated tolerance to infarction through superior survivability, improved ventricular conduction, and near-absence of pathological remodeling. Critically, spiny mice display increased vascularization, altered scar organization, and a more immature phenotype of cardiomyocytes, with a corresponding improvement in heart function. These findings present new avenues for mammalian heart research by leveraging unique tissue properties of the spiny mouse.

Effect of Resistance Exercise and Training and Principles of Prescribing it for Cardiovascular Patients

Introduction: The importance and necessity of preventing the occurrence of these diseases in order to maintain and promote health, has attracted the attention of many researchers to methods of preventing the occurrence of cardiovascular injury. Metabolic effects of muscle mass loss due to the natural aging process are caused by decreased muscle activity and lead to high prevalence of obesity, insulin resistance, type 2 diabetes, hyperlipidemia and cardiovascular disease. These risk factors cause disorders in the cardiovascular structure such as myocardial infarction, arterial stiffness and endothelial dysfunction, etc. Research also has shown that muscle strength is inversely related to all causes of death and the prevalence of metabolic syndrome. Therefore, the aim of this study was to provide safe resistance training methods for cardiovascular patients. Conclusion Resistance exercise is effective in preventing or reversing the functional, morphological and structural changes of the heart. Research shows that resistance training prevents the reduction of skeletal muscle mass and its function. This can also compensate for the functional decline caused by aging and disease. Because the methods of resistance training are various and are associated with many methodological problems, the study of the effect of exercise and resistance training in cardiovascular patients has always been controversial. This article reviews the findings of previous research examining the effects of the interaction between acute exercise and training in cardiovascular patients, and concludes the principles of prescribing resistance training in these patients. Overall, this study suggests that resistance training is beneficial even for the patients with CHF.

Resting ECG measurements can identify abnormalities in children with catecholaminergic polymorphic ventricular tachycardia

Background Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is a rare inherited disease characterized by exercise- or emotionally-triggered life-threatening ventricular arrhythmias. The resting ECG is considered to be normal and diagnosis has depended on exercise testing that is difficult acutely post-arrest or in young children. Purpose To identify resting ECG abnormalities in children with CPVT through assessment of measurement matrix parameters compared to a cohort of normal children. Methods A discovery cohort of 65 CPVT patients from the Electrophysiology program were identified. After excluding those on antiarrhythmics or in an arrhythmia at the time of their baseline ECG, 31 cases were matched 3:1 by age and sex with 93 healthy controls. Each individual had baseline ECG parameters and 180 machine-derived ECG amplitudes and durations (measurement matrix) measured. Statistical differences between ECG measures were assessed using Student's T-Test adjusted with a False Detection Rate of 1%. Significant measures were processed in a machine-learning algorithm to derive a Tree Model to differentiate individuals with and without CPVT. Results No significant differences were detected between CPVT patients who had and did not have a cardiac arrest. Comparing the CPVT and control cohorts, significant repolarization differences were seen in the amplitudes of lateral (I, negative aVR, V5, V6) and anterior leads (V2, V3, V4) at the J-point, ST midpoint, ST endpoint, and T-wave. Specifically, individuals with CPVT had significantly lower mean amplitudes in all aforementioned leads except aVR where the mean amplitudes were higher. These data were then used to create a Tree Model of the discovery cohort displayed in Figure 1 with a resulting R2 of 0.74, sensitivity of 0.81, and specificity of 0.98. Conclusions Baseline differences in repolarization are detectable in the left and anterior chest leads using machine-derived measurements of baseline ECGs in patients with CPVT, which may guide clinical suspicion when evaluating the resting ECG. These results warrant further analysis including testing of the Tree Model with a validation cohort. FUNDunding Acknowledgement Type of funding sources: Other. Main funding source(s): Scholar Award from the Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada to Trainee Dr. Taraneh TofighiCanadian Institute for Health Research Figure 1. CPVT Tree Model

Echocardiography in diagnosis of cardiovascular complications in patients who have undergone COVID-19, and echocardiographic study algorithm for this category of patients

The authors analyzed, classified and outlined the experience of working with patients who had suffered from COVID-19 disease to varying degrees of severity. Evaluated the possibilities of modern echocardiography in the diagnosis of complications of this infection from the heart, proposed the algorithm of ultrasound heart research in this category of patients. This year, the Recommendations of the European Association of Cardiology on the diagnosis and treatment of cardiovascular diseases in patients with coronavirus infection were published. These recommendations clearly describe the risk groups of complications of this pathology because COVID affects not the lungs but also the heart. The most vulnerable were patients with chronic diseases such as diabetes, blood diseases, chronic renal failure, cancer pathology, COPD. It is in these categories of patients that complications of infection from the lungs and heart were most common.

Emerging role of VCP/p97 in cardiovascular diseases: novel insights and therapeutic opportunities

Valosin-containing protein (VCP/p97) is a member of the conserved type II AAA+ (ATPases associated with diverse cellular activities) family of proteins with multiple biological functions, especially in protein homeostasis. Mutations in VCP/p97 are reportedly related to unique autosomal dominant diseases, which may worsen cardiac function. Although the structure of VCP/p97 has been clearly characterized, with reports of high abundance in the heart, research focusing on the molecular mechanisms underpinning the roles of VCP/p97 in the cardiovascular system has been recently undertaken over the past decades. Recent studies have shown that VCP/p97 deficiency affects myocardial fibers and induces heart failure, while overexpression of VCP/p97 eliminates ischemia/reperfusion injury and relieves pathological cardiac hypertrophy caused by cardiac pressure overload, which is related to changes in the mitochondria and calcium overload. However, certain studies have drawn opposing conclusions, including the mitigation of ischemia/reperfusion injury via inhibition of VCP/p97 ATPase activity. Nevertheless, these emerging studies shed light on the role of VCP/p97 and its therapeutic potential in cardiovascular diseases. In other words, VCP/p97 may be involved in the development of cardiovascular disease, and is anticipated to be a new therapeutic target. This review summarizes current findings regarding VCP/p97 in the cardiovascular system for the first time, and discusses the role of VCP/p97 in cardiovascular disease.

Research on Segmentation and Classification of Heart Sound Signals Based on Deep Learning

The heart sound signal is one of the signals that reflect the health of the heart. Research on the heart sound signal contributes to the early diagnosis and prevention of cardiovascular diseases. As a commonly used deep learning network, convolutional neural network (CNN) has been widely used in images. In this paper, the method of analyzing heart sound through using CNN has been studied. Firstly, the original data set was preprocessed, and then the heart sounds were segmented on U-net, based on the deep CNN. Finally, the classification of heart sounds was completed through CNN. The data from 2016 PhysioNet/CinC Challenge was utilized for algorithm validation, and the following results were obtained. When the heart sound segmented, the overall accuracy rate was 0.991, the accuracy of the first heart sound was 0.991, the accuracy of the systolic period was 0.996, the accuracy of the second heart sound was 0.996, and the accuracy of the diastolic period was 0.997, and the average accuracy rate was 0.995; While in classification, the accuracy was 0.964, the sensitivity was 0.781, and the specificity was 0.873. These results show that deep learning based on CNN shows good performance in the segmentation and classification of the heart sound signal.

Ischemic tolerance and cardiac repair in the African spiny mouse

Ischemic heart disease and by extension myocardial infarction is the primary cause of death worldwide, necessitating regenerative therapies to restore heart function. Current models of heart regeneration are restricted in that they are not of adult mammalian origin, precluding the study of class-specific traits that have emerged throughout evolution, and reducing translatability of research findings to humans. Here, we overcome those restrictions by introducing the African spiny mouse (Acomys spp.), a murid rodent that has recently been found to exhibit bona fide regeneration of the back skin and ear pinna. We show that spiny mice exhibit tolerance to myocardial infarction through superior survivability, improved ventricular conduction, smaller scar size, and near-absence of cardiac remodeling. Critically, spiny mice display increased vascularization and cardiomyocyte expansion, with an associated improvement in heart function. These findings present new avenues for mammalian heart research by leveraging unique tissue properties of the spiny mouse.