Method and apparatus for monitoring heart activity, detecting abnormalities, and cardioverting a malfunctioning heart
US4202340A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 1978 |
| Grant date | May 13, 1980 |
| Priority date | — |
| Expiry date | Feb 15, 1998 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3987
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Disclosed is a method and an apparatus for monitoring heart activity, for indicating or detecting abnormalities in such activity, and for taking corrective measures to return an arrhythmic heart to normal sinus rhythm. In one embodiment, monitoring and detecting are accomplished by developing a probability density function from ECG signals, or by sampling at least two portions of a probability density function. In another embodiment, a phase lock loop circuit is utilized to indicate fibrillation by the loop's inability to lock onto R--R interval signals. And in still another embodiment, cardiac electrodes are used to sense pulsatile impedance changes, absent in the presence of fibrillation. Also disclosed is a two-stage detector whose second stage is brought out of a stand-by state only after an arrhythmic condition is indicated by the first stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.