Method and apparatus for termination of ventricular tachycardia and ventricular fibrillation
US5224475A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1991 |
| Grant date | Jul 6, 1993 |
| Priority date | — |
| Expiry date | Nov 20, 2011 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3918
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An implantable defibrillator provided with a plurality of defibrillation electrodes, which may be reconfigured to define a plurality of defibrillation pathways. The device is capable of measuring the impedance along a selected defibrillation pathway, during delivery of an impedance pulse, and monitoring the success or failure of the pulse to accomplish defibrillation or cardioversion. In response to a detected failure to accomplish cardioversion in conjunction with a measured change of impedance of greater than a predetermined amount, a new defibrillation pathway is selected, which may employ some or all of the electrodes employed to define the original impedance pathway. The device also includes apparatus for varying the relative amplitude of defibrillation pulses applied to individual electrodes used in sequential or simultaneous, multiple electrode pulse regimens, in order to equalize current distribution, in response to measured pathway impedances.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.