Method and device for optimally altering stimulation energy to maintain capture of cardiac tissue
US6456879B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 5, 2000 |
| Grant date | Sep 24, 2002 |
| Priority date | — |
| Expiry date | Jan 25, 2021 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3712
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An improved system and method for performing automatic capture/threshold detection in an implantable cardiac stimulation device or any device capable of stimulating some body organ or tissue. Prior art systems determine the cardiac tissue's stimulation threshold by detecting an evoked response to a fixed duration stimulation pulse and then increasing the stimulation pulse's amplitude by a predetermined safety margin value. Such systems are inherently based upon a belief that the chronaxie of a particular patient's strength-duration curve is essentially fixed and that the rheobase is variable. While this may be true at some times during the patient's life, e.g., during the acute phase after lead implantation absent drug effects, it is reported that drugs alone may alter the chronaxie and it is believed that other factors may also affect the chronaxie either alone or in combination with the rheobase. Accordingly, the present invention compares the present stimulation pulse to at least two pulse duration regions and, if a loss-of capture criteria is met, alters the amplitude aid/or the duration of the stimulation pulse accordingly in order to take into account a rheobase and/or chrona…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.