Method and apparatus utilizing heart sounds for determining pressures associated with the left atrium
US5921935A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 2, 1997 |
| Grant date | Jul 13, 1999 |
| Priority date | — |
| Expiry date | Sep 2, 2017 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/037
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Non-invasive apparatus and method for obtaining a quantitative determination of mean left atrial transmural pressure or otherwise obtaining a quantitative determination of a left atrial pressure value. A balloon is inserted by means of a catheter into the esophagus and positioned adjacent the left atrium. The balloon is gradually inflated. A tracing of mean balloon pressure is obtained as the balloon is inflated. In addition, a tracing of balloon pressure on a steady baseline and with low frequency oscillations due to respiration filtered out is obtained whereby the tracing represents balloon pressure oscillations effected by left atrial pressure. In accordance with the oscillometric principle the mean balloon pressure is measured when the intensity of a sound wave, after its transmission through the balloon, is at a peak. This mean balloon pressure, after adjustment for the effect, if any, of heart weight, is indicative of approximate mean left atrial pressure. Mean left atrial transmural pressure may be determined by adjusting for the effects of heart weight and intrapleural pressure on mean pressure at peak sound intensity by subtracting therefrom the balloon pressure at which b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.