An interactive digital platform for arterial wave intensity analysis

Background: Wave intensity analysis (WIA) is a technique that is used for the evaluation of the working condition of the heart and the arterial system. Simultaneous measurements of blood pressure (P) and velocity (U) are required for calculating wave intensity (dI), which can also be determined non-invasively using U and diameter (D) of the vessel at the measurement site. The technique allows for the separation of P, U, D and WI into their forward and backward directions. Aim: This paper describes the development of an interactive digital platform that can be used to analyse arterial waves, determine WI, providing a range of cardiac and arterial indices. Methods and results: The platform is developed in Matlab, and operates interactively by allowing the user to select the data and the type of analysis based on the availability of the acquired signals. The user chooses to visualise the analysis of the raw signals or part of, and decide which set of results would be saved either in excel or '.txt' jiles, together with all the automatically generated graphs and tables. The wave speed is calculated using the PU-Loop or InDU-Loop techniques, automatically taking into consideration the possible lag between the velocity and pressure, or diameter using linear regression techniques. Also, the platform shows the separation of the forward and backward waves, whose meaningful indices are tabulated interactively with variations of wave speed. The platform is designed for batch analysis of large data-sets, and has been used for investigating signals taken in vivo of dogs which have undergone diferent hemodynamic manipulations. The results are in good agreement with those processed manually. Conclusion: The proposed platform is easy to use, saves computational time and effort for the assessment of a cardiac performance and arterial stiffness.