Unlike other methods
work on the pressure wave, the method analyses and identifies all
the pressure profile points during one heart cycle (systolic phase +
diastolic phase of a heart beat).
The Stroke Volume (SV [ml]) is obtained directly from the
relationship between the total area and the impedance of the
cardiocirculatory system without any other parameters that are
pre-calculated or obtained by means of CO calibration using other
techniques.
The SV is the relationship between the total area underneath the
pressure curve (diastolic-dichrotic) and the total impedance of the
system: the results are therefore the “sum” of a “prevalently
pulsatory” contribution superimposed on a “prevalently continuous”
contribution for both the area and the impedance.
Contributing to this impedance are all the profile points of a heart
cycle (in both the systolic and diastolic phase).
The pressure points thus obtained allow for estimating the total
impedance of the cardiocirculatory system, and are in fact assessed
and weighed in a different manner depending on the morphology of the
pressure wave. In this way it is possible to identify all the
impedance components contributing to the SV (Patent 1999, Patent
Pending USA).