Forward and inverse high-frequency electrocardiography
The high-frequency electrocardiogram (e.c.g.) contains useful clinical information about the heart condition that is not recorded in the conventional e.c.g. With simulated notches introduced in the heat dipole components and in the surface e.c.g., the forward and inverse problems of electrocardiography to correlate the standard 12-lead e.c.g. with the heart dipole were solved. It was shown that considerable notching activity in the heart dipole may be masked in the QRS complex of the body surface e.c.g. by large slopes or by cancellation effects. Furthermore, notches and slurs in the surface e.c.g. are observable even if the source (heart dipole) is notch-free. From theoretical analysis, the conclusion was reached that analysis of amplitudes and locations of notches and slurs in the vectorcardiogram can potentially be used clinically to obtain more information about the heart condition than the conventional technique of counting notches and slurs in the surface e.c.g. leads. The causes of notches are discussed and the sensitivity of each lead to notches is evaluated. Both homogeneous and inhomogeneous cases are examined.
KeywordsCardiac equivalent generator Dipole generator High fidelity electrocardiogram High frequency electrocardiogram Wideband electrocardiogram
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