Stiffness of Elastic

Stelari > Start is a new arterial stiffness index, independent of the influence of arterial pressure at the time of measurement, based on the theory of reversible ruptures during fluid movement in an extended space bounded by elastic walls, as well as the fundamental laws of conservation of momentum and mass. The Stelari Start stiffness index is not tied to a specific device and can be used to correct the effect of high blood pressure on the assessment of vascular stiffness by the pulse wave velocity measured by any device on any part of the arterial bed.

Authors: Igor Bakholdin, DrSci (Phys.-Math.), Viktor Milyagin, DrSci (Med), Med Inn LLC / Santens Group

Publication of RU2796752C1;  Stelari Start — ТМ №910488

How it works

Nonlinear equations were used in the calculation and the Stelari Start index better describes the elastic walls of the vessel with a large difference in systolic and diastolic pressure. The stiffness index is not tied to a specific device and can be used to correct the effect of high blood pressure on the pulse wave velocity obtained on any devices in any part of the arterial bed.

The Start index is always calculated for a specific section of the arterial bed based on its inherent pulse wave velocity.

The name of the index reflects the conditional letter designation of this section of the riverbed. For example, baStart, haStart, estStart and so on.

Taking into account the special clinical significance of the assessment of arterial stiffness in the plastic area (for example, carotid-femoral), for the elStart index (cfStart) we will introduce a special designation Stelari (Stiffness of elastic arteries index).

Stelari is an index based on the calculation of which is the speed of the «gold standard» — cfPWV, measured on verified devices

Example of haStart calculation for haPWV Vasera

рис. 1

We calculated haPWV based on the initial data of studies on Vasera VS1500n for more than 400 patients, and also took into account BP data at the time of measurement. We obtained haStart and compared it with the CAVI (cardio-ankle vascular index) calculated by Vasera and the classical stiffness index β calculated on the same data in the same patients.


«Comparison of the novel START vascular stiffness index with the CAVI index, assessment of their values and correlations with clinical parameters» — )


We saw a fairly high correlation of the ha Start, CAVI and β indices. This, taking into account completely different approaches to the methods of calculating Start and the stiffness index β, as well as the CAVI index derived from it, allows us to talk about the preliminary value of the new Start index and conclude about the mutual confirmation of Start and β as methods of eliminating the influence of blood pressure on the pulse wave velocity.

fig. 2

Calculate the Arterial Stiffness index Stelari > Start

To calculate, you will need a minimum of data: Ps, Pd, PWV.


If you want to process data from a single study, use the N1 method. If you have a large data set, use the N2 method.


Enter the data in the fields:

Your result:


Attach your data file in the format.xls or .csv*
* Sample file (click, to see the whole)
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Publication of RU2796752C1; Stelari Start — ТМ №910488

It is allowed to freely use the results of calculating the index using a calculator for scientific and research purposes.

The results of the calculation cannot be used to make a diagnosis or prescribe treatment. 

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