Cardiac output detection by multiple frequency thermodilution
US4236527A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 1978 |
| Grant date | Dec 2, 1980 |
| Priority date | — |
| Expiry date | Oct 20, 1998 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/028
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Method and apparatus for measuring cardiac output in which a traceable signal in the form of thermal energy or an injectate is applied to the blood flow through the heart having a plurality of frequency components with the traceable signal detected at a heart output vessel and analyzed at the plural frequency components to provide cardiac output rate and ejection fraction information. The traceable signal is preferably heat energy applied as a very low frequency modulation of a high frequency signal at a fundamental and further harmonic or as a square wave in which multiple harmonics are present. At least two frequency components of the square wave are then separately analyzed. A multiple frequency system in addition to permitting analysis of previously undetectable heart output characteristics additionally permits determination of whether the source of the traceable signal is properly located within the heart such as in the ventricle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.