Intracardiac electrogram sensing in an arrhythmia control system
US5395393A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 22, 1992 |
| Grant date | Mar 7, 1995 |
| Priority date | — |
| Expiry date | Jun 22, 2012 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/39622
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An implantable cardioverter/defibrillator device having an improved sensing system for automatically and rapidly adjusting to changing amplitudes of intracardiac electrogram "ICEG" signals during transitions between normal sinus rhythm and ventricular tachycardia/ventricular fibrillation of a patient's heart is disclosed. ICEG signals are sensed, amplified and filtered to remove high frequency and low frequency noise and artifacts therefrom. Crossings of positive and negative threshold levels by the filtered signals are detected and corresponding positive and negative output signals representative thereof are provided. The positive and negative threshold levels are varied in accordance with corresponding variations of fractions of the levels of the filtered signals so that the positive and negative threshold levels move independently of one another in response to changes in the levels of the filtered signals; and, the positive and negative output signals generated during each heart beat are rationalized so that only one output signal is provided per heart beat.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.