DESIGN, , FABRICATION AND APPLICATION OF VECTORCARDIOGRAPH

Abstract

The dissertation describes the design and application of the vectorcardiograrn — which is the manifestation of the electrical activity of the heart in the horizontal, sagittal and transverse planes of the body. In the introduction the dipole concept to describe the electrical activity of the heart has been introduced. Some general definitions are also given in the same chapter. Chapter 2 contains a description of the various vectorcardiographic lead systems. A short review of the uncorrected systemsused earlier is given along with a comparison between the vectorcardio_ graphic loops obtained using various lead systems. Design of the system to pick up the electrical signal from the body and to process i.t is contained in chap ter-3. Chapter-4 deals with the application of the vectorcardiograph. The use of the derived vectorcardio_ gram to solve the "inverse problem!' is discussed in detail. A review of some mathematical models of the heart, as a generator, proposed previously has been done and a new model assuming the body to be a homoge-neous, spherical conductor, has been proposed. Appendix 'A' deals with the mathematical analysis of 3 op_.Amp differential amplifier, Appendix 'B' with the derivation of surface potential due to the heart dipole and kv) Appendix IC' with is.:igner's and Abildskov and . Wilkinson's two reference frames_ used to derive the scalar ECG.s of the limb and precorclial leads from the frontal and transverse plane vectorcarcdiograrns