-
5
-
Vr
Vr
Vf
Vf
P1
P1
P2
P2
Differential
Pulse
Pulse
Pt
dPt
dt
Youngsters
Arteries Stiffening by Aging
Oldsters
AVI = (Vr/Vf) x 20
•
API (Arterial Pressure Volume Index)
API is a new vascular index that developed jointly by AIST and Shisei Datum in Japan.
Principle: The more elastic the arteries are, the more drastic the arterial volume changes when
the cuff pressure decreases. The blood vessel stiffness is converted into numerical values using
the gradient of the curve as an index. The higher the value is, the higher risk of upper-arm arterial
stiffness it represents. The cuff pressure-artery volume curve is firstly measured by a cuff with a
decreasing working pressure, then the curve is fitted with an arctan function (A*arctan(B*X+C)+D).
Finally, API is defined as the reciprocal of coefficient B (API=1/B).
CSBP
(
Estimated Value
)
& CAPP
(
Estimated Value
)
•
CSBP (Central Systolic Blood Pressure,
estimated value
)
It is cobtained by taking age, radial artery systolic pressure, pulse pressure, arterial velocity pulse
index, arterial pressure volume index and other parameters as independent variables.
CSBP (Estimated Value) = 0.0447*age + 0.8392*PSBP + 0.1793*PDBP + 0.2718*AVI + 0.2881*API +
2.3339
•
CAPP (Central Aortic Pulse Pressure,
estimated value
)
It is cobtained by taking age, radial artery systolic pressure, pulse pressure, arterial velocity pulse
index, arterial pressure volume index and other parameters as independent variables.
CAPP (Estimated Value) = 0.1613*age + 0.0923*PSBP + 0.8192*PPP + 0.2024*AVI + 0.2537*API -
13.1126