The most significant experimental data about the formation of a uniform rhythm of the sinoatrial unit of the heart for both the intact sinoatrial unit of the heart and cardiomyocytes in cellular structures are presented. The basic mathematical models for studying the processes of synchronization in the sinoatrial unit of the heart are described, including equations of Noble, Bonhoffer, and van der Pol and modified axiomatic models. The basic results obtained using the mathematical models are presented. The major reasons influencing the formation of a uniform rhythm were revealed: the form of a potential pacemaker in the phase of slow diastolic depolarization, its porosity, the force of connection between pacemaker and electric capacity of pacemakers. A study of rhythmogenisis on the basis of the modified axiomatic model was carrud out. The method allows one to calculate the uniform rhythm of the sinoatrial unit of the heart in view of the mutual influence of pacemaker cells, including the force of connection, electric capacity of cells, their possible clusterization. It was shown that generally the uniform rhythm of the sinoatrial unit of the heart is formed on an intermediate level of all pacemaker cells.
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Front Genet
May 2024
Department of Cardiology, The Affiliated Children's Hospital of Xiangya School of Medicine, Central South University (Hunan Children's Hospital), Changsha, China.
Objective: The aim of this study was to analyze the diagnosis, treatment, and follow-up of six cases of complex arrhythmias associated with gene mutations in children.
Method: A retrospective analysis was conducted on six children diagnosed with complex arrhythmias associated with gene mutations. The study included an analysis of the age of onset, initial symptoms, electrocardiographic characteristics, genetic results, treatment course, and follow-up outcomes.
Nurs Crit Care
June 2024
McMaster University and Population Health Research Institute, Hamilton, Ontario, Canada.
Background: Cardiovascular failure is recognized as a common final pathway at the end of life but there is a paucity of data describing terminal arrhythmias.
Aim: We aimed to describe arrhythmias recorded peri-mortem in critically ill patients.
Study Design: We enrolled intensive care unit patients admitted to two tertiary Canadian medico-surgical centres.
Anat Sci Int
May 2024
Unit of Anatomy, Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal.
Several studies reported anatomical variations in the sinoatrial node artery (SANa). Here, we report a rare variation in the origin of the SANa on a human adult male cadaver. During dissection, we identified the SANa originating from a large atrial branch of the right coronary artery (RCA).
View Article and Find Full Text PDFStem Cell Res Ther
May 2024
Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Indonesia-National Heart Center Harapan Kita, Jakarta, 10430, Indonesia.
J Clin Med
April 2024
Department of Intensive Care, Hôpital Erasme, Université Libre de Bruxelles, 1070 Brussels, Belgium.
In patients with septic shock, compensatory tachycardia initially serves to maintain adequate cardiac output and tissue oxygenation but may persist despite appropriate fluid and vasopressor resuscitation. This sustained elevation in heart rate and altered heart rate variability, indicative of autonomic dysfunction, is a well-established independent predictor of adverse outcomes in critical illness. Elevated heart rate exacerbates myocardial oxygen demand, reduces ventricular filling time, compromises coronary perfusion during diastole, and impairs the isovolumetric relaxation phase of the cardiac cycle, contributing to ventricular-arterial decoupling.
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