The study of human cardiovascular activity is one of the main methods for assessing the health of the human. It is performed in clinical conditions via electrocardiographic devices and in the daily life of a individuals through Holter monitoring. An important diagnostic parameter that can be determined by an electrocardiogram, taking into account the difference between successive heartbeat is heart rate variability – a widely used non-invasive method of measuring heart rate. This parameter makes it possible to assess the risk of various cardiac diseases such as angina, cardiac infarction, life-threatening arrhythmias, etc. This chapter presents the morphological bases of the cardio records, heart rate variability, and its impact on the healthy status of the individual. It describes the created cardiology base of prolongated Holter recordings for the purposes of scientific research project. Presented are internationally approved standards to provide web accessibility to internet-based data bases and other resources for people with disabilities.
TopIntroduction
The work on this Chapter is closely related to work of a team of young scientists on tasks of a scientific project: “Investigation of Mathematical Techniques of Analysis of Physiological Data with Functionality for People with Visual Deficit”, funded by Fund for Scientific Research at Ministry of Education and Science of Republic of Bulgaria.
Two of team's tasks for given project, which are presented in Chapter, are following:
- 1.
The main task of this project is study the modern mathematical technologies for processing and analysis of prolonged time sequences of physiological data (specifically cardiological data). The investigations will be performed on real patient prolonged data by conducting holter monitoring of patients' cardiac activity.
- 2.
Тhe second task is to explore the possibilities of modern information technologies to provide resources, conditions, ways in this scientific activity can include people with visual deficits - ie. people with visual deficits can participate in research itself - they themselves research data, they analyze data, they use data processing software and analyze data. The assignment of such a task results from the fact that in project team has involved participant with visual deficit, who conducts scientific activity.
In this Chapter (in order to accomplish the first task), the morphological bases of cardiological data (basic elements in an electrocardiogram and its graphic appearance) are presented, the means for obtaining these patient data are described, and mathematical technologies for their analysis are examined.
The two main ways of obtaining cardiological data are described: via standard stationary device of the human body and by conducting Holter monitoring in which one performs his usual work.
In this Chapter concept of Heart Rate Variability (reflecting the variability of cardiac intervals over the time) is presented, the way it is received and studied, and the methods for its evaluation. Both types of Heart Rate Variability (HRV) are shown graphically: normal and abnormal.
One of the tasks assigned to the project team is to inform the public in Bulgaria and around the world on the issues of accessibility of data bases in Web (e.g. information bases of cardiological data that are being studied using modern mathematical technologies). The goal is to give publicity of problems encountered by People with Visual Deficit (as well all people with special needs), accessing information resources on the web, and showing ways and methods to address these issues. This Chapter examines established international Standards designed to help developers of web-based information resources and shows how to implement them.
The guidance given in the latest version of the internationally accepted Web Accessibility Standard will be used in the design, creation and maintenance of information databases containing annotated prolonging cardiological data and software programs for data analysis.
TopBackground
Cardiovascular diseases throughout the world continue to increase over the last decades, despite remarkable advances in their prophylaxis and treatment. They are the number one cause of death among European populations. Bulgaria is among the countries in the European Union with the highest morbidity and mortality from cardiovascular diseases. According to data from the Bulgarian Cardiology Society, 60% of mortality in Bulgaria is the result of heart disease. These diseases are also a major factor in disabling the population, which leads to a decrease in the quality of life. Research studies in this area indicate that cardiovascular disease can be reduced by early detection, prognosis and prevention.
Electrocardiography is one of leading medical non-invasive methods to study the condition of the cardiovascular system of the human body. The electrocardiogram (ECG) is a linear graphic recording of electrical activity of heart muscle during cardio cycles and is a standard procedure in medicine. The first human ECG was published in 1887 by British physiologist Waleer, and the first ECG record on paper was carried out in 1903 by the Dutch physiologist Willem Einthoven. The development of methods of processing, analysis and compression of cardiological data goes through several stages during years and continues to be improved in Nowdays. In the study of long-term electrocardiogram data are generates a huge amount of data, and therefore it is preferable to use automated processing and analysis methods.
Currently there are a number of directions for research, processing and analysis of cardiological data (signals):