Definition of rector for English Language Learners. : 1  a priest or minister who is in charge of a church or parish. : 2  a person who is in charge of a university or school.
Cardiac Cycle. in Physiology. Cardiac events appearing from the beginning of one heart beat to the beginning of next heart beat and repeating themselves successively. â¢ Cardiac cycle time (H.Rate = 75/min) : 0.8 sec. Systole: 0.27 sec. Diastole: 0.53 sec.
While heart rate focuses on the average beats per minute, heart rate variability (HRV) measures the specific changes in time (or variability) between successive heart beats. The time between beats is measured in milliseconds (ms) and is called an âR-R intervalâ or âinter-beat interval (IBI).â.