Tissue characterization using intracardiac impedances with an implantable lead system
US8010196B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 2007 |
| Grant date | Aug 30, 2011 |
| Priority date | — |
| Expiry date | Sep 17, 2028 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3627
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An implantable system acquires intracardiac impedance with an implantable lead system. In one implementation, the system generates frequency-rich, low energy, multi-phasic waveforms that provide a net-zero charge and a net-zero voltage. When applied to bodily tissues, current pulses or voltage pulses having the multi-phasic waveform provide increased specificity and sensitivity in probing tissue. The effects of the applied pulses are sensed as a corresponding waveform. The waveforms of the applied and sensed pulses can be integrated to obtain corresponding area values that represent the current and voltage across a spectrum of frequencies. These areas can be compared to obtain a reliable impedance value for the tissue. Frequency response, phase delay, and response to modulated pulse width can also be measured to determine a relative capacitance of the tissue, indicative of infarcted tissue, blood to tissue ratio, degree of edema, and other physiological parameters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.