Method and apparatus to correct for electric field non-uniformity in conductance catheter volumetry
US5971933A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 27, 1997 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Aug 27, 2017 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2562/043
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A method of determining cardiac volume including the steps of positioning a catheter in a blood-filled chamber of a patient's heart. The catheter comprises an elongated body having a distal end, a proximal end, a plurality of spaced electrodes arrayed on the outer surface of the catheter and spaced apart a predetermined distance from each other to define a distal electrode, a proximal electrode and a plurality of pairs of adjacent electrodes between the distal and proximal electrodes to define volume segments within the chamber. The method includes the steps of providing a constant alternating current to the distal and proximal electrodes, measuring the potential between pairs of electrodes located between a distal and proximal electrodes while the distal and proximal electrodes are energized with the constant amplitude alternating current; determining a set of correction factors from the measured raw segmental volumes and catheter curvature; and correcting for field non-uniformity by multiplying the raw volumes by the set of correction factors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.