Abstract: Methods, systems and apparatus for monitoring equivalent inner diameter of arteriole-like blood vessels and related cardiovascular parameters, where by measuring a time difference between signals from larger blood vessels, like arteries (excluding arterioles), and smaller blood vessels, similar to arterioles by their physiologic properties, also taking concurrent heart rate value into account. In case the signal from larger blood vessels is measured geometrically relatively far from such a signal from smaller, arteriole-like blood vessels, said measured time difference may be evaluated by several ways in order to separate a PWTT component of time differences, obtained from said measured signals, from transient time component, including information about changes of diameter in arteriole-like vessels. It also may be effective defining more correctly the role of blood viscosity in monitored vascular condition of patient.

Abstract: Methods for monitoring equivalent inner diameter of arterioles by measuring blood pressure wave transient time from small arteries to arterioles and calculating, from the transient time and concurrently measured heart rate values, an equivalent inner diameter of arterioles.

Abstract: Methods, systems and apparatus for monitoring equivalent inner diameter of arteriole-like blood vessels and related cardiovascular parameters, where by measuring a time difference between signals from larger blood vessels, like arteries (excluding arterioles), and smaller blood vessels, similar to arterioles by their physiologic properties, also taking concurrent heart rate value into account. In case the signal from larger blood vessels is measured geometrically relatively far from such a signal from smaller, arteriole-like blood vessels, said measured time difference may be evaluated by several ways in order to separate a PWTT component of time differences, obtained from said measured signals, from transient time component, including information about changes of diameter in arteriole-like vessels. It also may be effective defining more correctly the role of blood viscosity in monitored vascular condition of patient.

Abstract: The present invention relates to a system, method and apparatus for measuring vascular parameters and, more particularly, but not exclusively, to a system, method and apparatus for monitoring changes in the equivalent inner diameter of small branching arteries and arterioles. An aspect of some embodiments of the invention concerns finding a measure of a blood flow dependent parameters in small arteries, and in arterioles that branch off them, and using them and differences between them to find information about the equivalent inner diameter of said arterioles, and/or about changes in said diameter of the arterioles.