Cardiac Imaging for the Assessment of Left Atrial Mechanics Across Heart Failure Stages

The left atrium (LA) is emerging as a key element in the pathophysiology of several cardiac diseases due to having an active role in contrasting heart failure (HF) progression. Its morphological and functional remodeling occurs progressively according to pressure or volume overload generated by the underlying disease, and its ability of adaptation contributes to avoid pulmonary circulation congestion and to postpone HF symptoms. Moreover, early signs of LA dysfunction can anticipate and predict the clinical course of HF diseases before the symptom onset which, particularly, also applies to patients with increased risk of HF with still normal cardiac structure (stage A HF). The study of LA mechanics (chamber morphology and function) is moving from a research interest to a clinical application thanks to a great clinical, prognostic, and pathophysiological significance. This process is promoted by the technological progress of cardiac imaging which increases the availability of easy-to-use tools for clinicians and HF specialists. Two-dimensional (2D) speckle tracking echocardiography and feature tracking cardiac magnetic resonance are becoming essential for daily practice. In this context, a deep understanding of LA mechanics, its prognostic significance, and the available approaches are essential to improve clinical practice. The present review will focus on LA mechanics, discussing atrial physiology and pathophysiology of main cardiac diseases across the HF stages with specific attention to the prognostic significance. Imaging techniques for LA mechanics assessment will be discussed with an overlook on the dynamic (under stress) evaluation of the chamber.

Disease Classification Using ECG Signals Based on R-Peak Analysis With ABC and ANN

ECG feature extraction has an important role in identifying a number of cardiac diseases. Lots of work has been done in this field but the most important challenges faced in previous work are the selection of proper R-peaks and R-R intervals due to the lack of appropriate pre-processing steps like decomposition, smoothing, filtering, etc., and the optimization of the features for proper classification. In this article, DWT-based pre-processing and ABC is used for optimization of features which helps to achieve better classification accuracy. It is utilized for initial diagnosis of abnormalities. The signals are taken from MIT-BIH arrhythmia database for the analysis. The aim of the research is to classification of six diseases; Normal, Atrial, Paced, PVC, LBBB, RBBB with an ABC optimization algorithm and an ANN classification algorithm on the basis of the extracted features. Various parameters, like, FAR, FRR, and accuracy are measured for the execution. Comparative analysis is shown of the proposed and the existing work to depict the effectiveness of the work.

Invasive hemodynamic assessment of patients with cardiomyopathies

Invasive hemodynamic assessment of cardiac diseases has become an important diagnostic tool in recent decades. Non-invasive methods are the main techniques used to assess cardiac function, due to their wider availability. Cardiac catheterization is useful when there are diagnostic problems that cannot be solved with routine methods. Cardiac catheterization should be individualized according to the specific problems of the patient and based on the results from non-invasive methods. Invasive diagnostics is used in the assessment of patients with various cardiovascular diseases, including cardiomyopathies. In this review, we consider the role of cardiac catheterization, its advantages and disadvantages as part of the overall assessment of patients with cardiomyopathies.  

The Incidence of Dysarrhythmias, Their Types and Outcomes in Patients Hospitalized with COVID -19

Background: COVID-19 infection started in China and became a pandemic, the SARS-CoV-2 virus mainly affects the respiratory system but can insult the cardiovascular system as well, higher rate of cardiac arrhythmias noted during the pandemic, and many studies showed that COVID-19 (especially hospitalized patients) can develop different types of arrhythmias which cause higher mortality rate. Objective: To assess the incidence of dysrhythmias and their types and outcomes in hospitalized patients with COVID-19 in Erbil city. Patients and Methods: Patients with documented COVID-19 infection admitted in Erbil Teaching Hospital respiratory care unit and coronary care unit from 1-8-2020 to 30-10-2020 had been included (255 patients) in this cross-sectional study, demographic data, and outcomes were reported, the ECG analyzed by cardiologists and the type of arrhythmia documented. Results: Mean age was 47±12 years, 61% of the patients were male, 25% of them had previous cardiac diseases, 20% diabetes, 16% multiple comorbidities, 8% hypertension, 8% obesity and 23% had no comorbidities, 20.7% of in-hospital patients developed dysrhythmias, 5.9% of them developed sinus tachycardia, 4.7% atrial fibrillation, 3.9% ventricular premature contractions, 2% ventricular fibrillation, 1.9% ventricular tachycardia and 1.9% heart blocks. Most of the patients who developed ventricular arrhythmias, atrial fibrillation, and heart block had previous comorbidities 82%, 62%, and 80% respectively. Arrhythmias caused a higher in-hospital mortality rate (39.6% versus 21.7%) especially among male patients (mortality rate in male patients 43% compared with female patients 33%). Conclusion: Most of the admitted cases were male. Most of them had comorbidities especially previous cardiac diseases. Sinus tachycardia, atrial fibrillation, and ventricular extra-systoles were the most frequent arrhythmias. The mortality rate was increased by arrhythmias mainly in male patients. Keywords: COVID-19, Dysrhythmias, Outcomes, Pandemic

The Potential of Hsp90 in Targeting Pathological Pathways in Cardiac Diseases

Heat shock protein 90 (Hsp90) is a molecular chaperone that interacts with up to 10% of the proteome. The extensive involvement in protein folding and regulation of protein stability within cells makes Hsp90 an attractive therapeutic target to correct multiple dysfunctions. Many of the clients of Hsp90 are found in pathways known to be pathogenic in the heart, ranging from transforming growth factor β (TGF-β) and mitogen activated kinase (MAPK) signaling to tumor necrosis factor α (TNFα), Gs and Gq g-protein coupled receptor (GPCR) and calcium (Ca2+) signaling. These pathways can therefore be targeted through modulation of Hsp90 activity. The activity of Hsp90 can be targeted through small-molecule inhibition. Small-molecule inhibitors of Hsp90 have been found to be cardiotoxic in some cases however. In this regard, specific targeting of Hsp90 by modulation of post-translational modifications (PTMs) emerges as an attractive strategy. In this review, we aim to address how Hsp90 functions, where Hsp90 interacts within pathological pathways, and current knowledge of small molecules and PTMs known to modulate Hsp90 activity and their potential as therapeutics in cardiac diseases.

A Review on Cardioprotective Mechanism of Chemical Constituents of Medicinal Plants

Plants are the major source of human living. Since the beginning of the era, plants have been used for medicinal purposes. There is dire to explore the mechanism of chemical constituents in plants and particularly saponins, cardiac glycosides, and flavonoids due to their mechanism to save damaged cells in cardiac muscle. Databases like Google Scholar, Medline, PubMed, and the Directory of Open Access Journals were searched to find the articles describing the cardioprotective mechanism of medicinal plants. Saponin, flavonoids, glycoside, steroid, alkaloids, tannin, phenol, phlorotannin, terpenoids, and anthraquinone are chemical constituents in plants that enhance cardioprotection activity and decreases cardiac abnormalities. The current review article provides data on the use of medicinal plants, specifically against cardiac diseases, as well as an investigation of molecules/phytoconstituents as plant secondary metabolites for their cardioprotective potential.

The Potential of Gamma Secretase as a Therapeutic Target for Cardiac Diseases

Heart diseases are some of the most common and pressing threats to human health worldwide. The American Heart Association and the National Institute of Health jointly work to annually update data on cardiac diseases. In 2018, 126.9 million Americans were reported as having some form of cardiac disorder, with an estimated direct and indirect total cost of USD 363.4 billion. This necessitates developing therapeutic interventions for heart diseases to improve human life expectancy and economic relief. In this review, we look into gamma-secretase as a potential therapeutic target for cardiac diseases. Gamma-secretase, an aspartyl protease enzyme, is responsible for the cleavage and activation of a number of substrates that are relevant to normal cardiac development and function as found in mutation studies. Some of these substrates are involved in downstream signaling processes and crosstalk with pathways relevant to heart diseases. Most of the substrates and signaling events we explored were found to be potentially beneficial to maintain cardiac function in diseased conditions. This review presents an updated overview of the current knowledge on gamma-secretase processing of cardiac-relevant substrates and seeks to understand if the modulation of gamma-secretase activity would be beneficial to combat cardiac diseases.

Insights to Heart Development and Cardiac Disease Models Using Pluripotent Stem Cell Derived 3D Organoids

Medical research in the recent years has achieved significant progress due to the increasing prominence of organoid technology. Various developed tissue organoids bridge the limitations of conventional 2D cell culture and animal models by recapitulating in vivo cellular complexity. Current 3D cardiac organoid cultures have shown their utility in modelling key developmental hallmarks of heart organogenesis, but the complexity of the organ demands a more versatile model that can investigate more fundamental parameters, such as structure, organization and compartmentalization of a functioning heart. This review will cover the prominence of cardiac organoids in recent research, unpack current in vitro 3D models of the developing heart and look into the prospect of developing physiologically appropriate cardiac organoids with translational applicability. In addition, we discuss some of the limitations of existing cardiac organoid models in modelling embryonic development of the heart and manifestation of cardiac diseases.