Fig. 5.

Fiducial points to be identified and used for IBI estimation. The onset points represent the start and end for each cardiac cycle, the max slope point gives insight into the rate of change in blood pressure as the heart contracts, and the systolic peak is directly correlated to the maximum pressure of the blood flow through this region of the body after it is pumped from the heart. Each of these fiducial points are commonly used in the estimation of several physiological parameters, including IBI, HR, HRV, BP, RR, and others.