Measurement of the approximate elapsed time of ventricular fibrillation and monitoring the response of the heart to therapy
US5077667A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 1990 |
| Grant date | Dec 31, 1991 |
| Priority date | — |
| Expiry date | Jun 13, 2010 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/7257
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The approximate elapsed time since the onset of ventricular fibrillation is detected from an analog electrocardiogram signal. The signal is digitized for a time interval of four seconds to obtain a data set of time domain samples. These time domain samples are Fourier transformed to a frequency domain spectrum and the median frequency which bisects the energy of the power spectrum is detected. That median frequency is then compared to a pattern of experimentally obtained median frequency data as represented by a mathematical algorithm to calculate the estimated time from the onset of ventricular fibrillation. This frequency parameter can also be used to evaluate the response to therapy during ventricular fibrillation and CPR, as well as estimate the most appropriate time to defibrillate a subject following various pharmacologic and mechanical intervention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.