Estimating cardiac output and ejection fraction using blood pressure signal

Cardiac output (CO) is a cardinal parameter of cardiovascular system, and a fundamental determinant of global oxygen delivery. Also, Left ventricular ejection fraction (EF) which is the ratio of the stroke volume to the end-diastolic volume of the left ventricle, is widely recognized as one of the most clinically significant indices of cardiac function. Current methods for measuring both of them are invasive methods but by using arterial blood pressure which may be measured continuously with little or no invasion, we can calculate CO and EF. In this paper, we have estimated CO and EF based on Windkessel model and using arterial blood pressure (ABP). We have used system identification (ARX method) to reconstruct the ABP signal and Windkessel model to estimate cardiovascular indices such as CO, EF, SV, EDV and ESV.