摘要 |
This invention is a non-invasive apparatus and method, which need not require a physician for use thereof, for obtaining quantitative determinations of left atrial pressure values. A balloon (24) is inserted by means of a catheter (22) into the esophagus and positioned adjacent the left atrium. The balloon (24) is gradually inflated. 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 (24), 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 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 balloon volume begins to increase greatly relative to the increase in balloon pressure.
|