Method and apparatus for rate-responsive cardiac pacing
US5562711A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1994 |
| Grant date | Oct 8, 1996 |
| Priority date | — |
| Expiry date | Nov 30, 2014 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/36585
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A body-implantable rate-responsive cardiac pacemaker is provided with circuitry for sensing a plurality of physiologic parameters known to be indicative of a patient's metabolic demand for increased cardiac output. In one embodiment, a rate-responsive pacemaker is provided with an activity sensor for detecting the patient's level of physical activity, and is further provided with an impedance sensing circuit for detecting the patient's level of minute ventilation by monitoring cardiac impedance. A rate-response transfer function, implemented by the pacemaker's control circuitry, periodically computes a rate-responsive pacing rate as a function of the outputs from both physiologic sensing circuits. The pacemaker's pacing rate is variable within a rate range defined by predetermined (programmable) upper and lower limits. In the preferred embodiment, the influence of activity sensing and minute ventilation parameters varies in accordance with the current pacing rate. In particular, the influence of activity sensing in rate determination in accordance with the rate-response function is greater than that of minute ventilation, for slower pacing rates, while the influence of minute venti…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.