Method and apparatus for vector analysis of ECG arrhythmias
US4136690A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 1977 |
| Grant date | Jan 30, 1979 |
| Priority date | — |
| Expiry date | Oct 31, 1997 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/7264
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
ECG signals from two approximately orthogonal leads are combined in a rectangular-to-polar coordinate converter to obtain signals representing the magnitude and angle of the vector. The vector angle existing at the instant the magnitude of the QRS vector reaches its peak is first identified, and a voltage corresponding to the vector angle is sampled and stored for later use. Secondly, the vector angle existing at the instant the magnitude of the T-wave vector reaches its peak later in the cardiac cycle, is identified, and a voltage corresponding to this second vector angle is sampled and stored. The voltages representing the QRS and the T-wave vector angles are then applied to a differential amplifier to obtain a difference voltage representing the angular difference existing between the two maximal vectors. This angular difference possesses certain characteristics which are diagnostically significant. A classifying circuit determines which one of a number of angular ranges the angular difference falls into. A counter is provided for each angular range to accumulate over successive heartbeats the number of differences which have fallen into each of the angular ranges, and the cumul…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.