| 摘要 |
Cardiac performance is measured by measuring the left ventricular pressure, measuring the left ventricular volume, determining the product of the left ventricular pressure and the left ventricular volume as a function of time, determining the time derivative of said product; and determining the slope of the time derivative, as it rises thereby to provide an indication of the cardiac power index. In this invention, the left ventricular pressure is measured by measuring the arrival times of cardiac pressure pulses at a given site at a plurality of pressure values. Preferably, the largest number of pressure measurements is conducted in the interval during the early ejection phase. This method reliably measures cardiac performance under resting and/or exercise stress conditions to enable measurement of the cardiac power index.
|
