Implantable defibrillator system for generating a biphasic waveform with enhanced phase transition
US5913877A · kind A · utility
Inventors
Key dates
| Filing date | Aug 15, 1997 |
| Grant date | Jun 22, 1999 |
| Priority date | — |
| Expiry date | Aug 15, 2017 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3912
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A method and apparatus for generating biphasic waveforms uses an implantable cardioverter defibrillator (ICD) system having a phase transition enhancing capacitor system in addition to the capacitor system(s) which deliver the first and second phase of the biphasic countershock. Preferably, the ICD system has at least three capacitor systems and a capacitor switching network. The three capacitor systems include two primary capacitor systems and a third high voltage phase transition enhancing capacitor system having a time constant shorter than the time constant of the two primary capacitor systems. A first phase of the biphasic waveform preferably is produced by configuring the two primary capacitor systems to selectively discharge first in a parallel combination, and then in a series combination. The second phase of the biphasic waveform preferably is produced by reconfiguring the two primary capacitor systems to discharge in a parallel combination with reversed polarity. The phase transition enhancing capacitor system is selectively switched into the discharge of the biphasic waveform so as to effectively increase the voltage differential seen by the heart during the transition b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.