Table 1 Description of the digital pulse wave analysis variables used in the study, revised from von Wowern et al. [5]

Pulse height (PH)

Circulation in small finger arteries, perfusion of finger tips

High BP, hyperthyroidism, fever, anemia, excessive blood volume, exercise, well-tuned athlete

Peripheral vaso-constriction, low BP, hypovolemia/dehydration, hypothyroidism, increased peripheral resistance

Peripheral vasodilatation

Peripheral vasoconstriction

Left ventricular ejection time compensated (ETc)

Represents systole, i.e. time from onset of the systolic upstroke limb to the closure of the aortic valve

Aortic valve stenosis, increased large artery compliance (low vascular tone)^a

LV failure, decreased preload, hypovolemia, decreased large artery compliance (high vascular tone) ^a

Increase in LV ejection time,

Decreased afterload, decreased SVR, increased preload ^a

Decrease in LV ejection time,

Increased afterload, increased SVR, decreased preload ^a

Cardiac ejection elasticity index (EEI)

Index for LV ejection capacity and compliance/elasticity of large arteries

Large artery vasodilatation, anemia, increased LV ejection power, hyperthyroidism, congested heart failure

Large artery vasoconstriction, arteriosclerosis, LV ejection insufficiency

Increase in LV ejection power, large artery vasodilatation

Decrease in LV ejection power, large artery vasoconstriction

Dicrotic index (DI)

Represents the peripheral circulation, indicates peripheral resistance

Small artery vasoconstriction

Small artery vasodilatation

Peripheral vasoconstriction

Peripheral vasodilatation

b/a

Early systolic PW peaks identified by second derivatives of the crude PW curve contour; indicates LV ejection capacity and large artery compliance/elasticity

Low large artery elasticity, increased cardiovascular risk, vasoconstriction, atherosclerosis, increases by age

Young persons, athletes

Large artery vasoconstriction, decreased LV ejection

Large artery vasodilatation, increased LV ejection

d/a

d is a late systolic PW peak identified by second derivative of the crude PW curve contour; mainly reflects the intensity of the tidal PW from small peripheral arteries

High small artery elasticity, young persons

A longer negative d peak develops by advancing age, indicating arterial stiffness, atherosclerosis

Small artery vasodilatation

Small artery vasoconstriction

Ageing index (AI)

AI = (b-c-d-e)/a, representing the global vascular stiffness, i.e. “vascular age”

Atherosclerosis, increases by age

Young persons, athletes

Global arterial vasoconstriction

Global arterial vasodilatation