Implantable cardiac stimulator with capture detection and impedance based autotuning of capture detection
US5718720A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 13, 1996 |
| Grant date | Feb 17, 1998 |
| Priority date | — |
| Expiry date | Dec 13, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3712
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An implantable cardiac stimulator for detecting capture or adjusting the strength or duration of pacing pulses by using an evoked response detector and periodically tuning the evoked response detector. When the electric evoked response detector is to be tuned, capture is verified by detecting the mechanical evoked response. As the magnitude of the stimulating pulse is adjusted to isolate the threshold as detected by the mechanical response detector. At the same time, the electrical evoked response is also monitored. The difference between the detected electrical signal following capture as detected by the mechanical response detector and the signal following non-capture is used to tune the electrical evoked response detection apparatus and algorithm. The energy of the pacing pulse can then be optimized by adjusting both strength and duration. A very small safety margin is needed since capture is continuously monitored by the electrical evoked response apparatus and a safety pulse is immediately applied if capture is lost. The safety pulse can be applied in the same cardiac cycle so that the heart beat remains controlled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.