血压变异性(blood pressure variability,BPV)是指一段时间内血压变化的程度[1]。根据观察时间的长短,血压变异可分为心动周期间变异、短时变异和长期变异三类[2]。心动周期间变异是不同心动周期之间的血压差异,例如血压高低与呼吸周期有关。临床上更为关注的是血压的短时变异和长期变异。 Blood pressure variability (BPV) is the degree of change in blood pressure over a period of time [1]. According to the length of observation time, blood pressure variation can be divided into cardiac cycle variation, short-term variation and long-term variation in three categories [2]. Variation during cardiac cycle is the difference in blood pressure between different cardiac cycles, for example, the level of blood pressure is related to the respiratory cycle. More clinically concerned are short-term and long-term variations in blood pressure.