Y THE TIME the patient with acute myocardial infarction is first examined, his electrocardiogram may already show changes in the RS-T segment alone, in the T wave alone, in the QRS complex alone, or in any combination of the three. Changes in any of these portions of the ventricular complex and particularly in the QRS may not appear for hours or days. Some never show distinctive electrocardiogr...

background: various techniques are used in diagnosing cardiac diseases. the electrocardiogram is one of these tools in common use. in this study vectorcardiogram ) vcg ( signals are used as a tool for detection of cardiac ischemia. methods: vcg signals used in this study were obtained form 60 patients suspected to have ischemia disease and 10 normal candidates. verification of the ischemia had ...

The amount of data available greatly increases every year and information can be quite valuable in the right hands. The existing mechanisms for selling goods, such as VCG, cannot handle sharable goods, such as information. To alleviate this limitation, in this paper, we study mechanisms for selling goods that can be shared or copied. We present and analyze theoretically and experimentally effic...

For a realistic biophysical model, a linear deformation of the myocardium lead to a linear transformation of the orthogonal electrocardiosignals under the condition of topological invariability of the depolarization and repolarization processes in the myocardium. Certain relationships have been found between the linear transformations in the physical and functional spaces. Several practically i...

A new method for extracting respiratory signals from the ECG/VCG is presented. The method is based on the alignment of an observed VCG loop to a reference loop with respect to the transformations of rotation and time synchronisation. The resulting series of estimated rotation angles reflects respiratory-induced changes in the electrical axis of the heart. The respiratory frequency is estimated ...

It is usual for various investigators to use their own system of vectorcardiography. Such a system is characterized by the place of the electrodes and the way in which the vectorcardiogram is deduced from the potential differences obtained. At present the system according to Duchosal and Sulzer (1949) and the one proposed by Wilson et al. (1947) are much in use. The equilateral tetrahedron prop...