Impact of Short-Term Heart Rate Variability in Patients with STEMI Treated by Delayed versus Immediate Stent in Primary Percutaneous Coronary Intervention: A Prospective Cohort Study

Table 5

Heart rate variability of IS group after second angiography.

	None stent implantation group ()	Stent implantation group ()	value
Frequency-domain measures
VLF (ms^2)			0.416
LF (ms^2)			0.850
HF (ms^2)			0.063
5 min total power (ms^2)			0.872
LF/HF			0.256
Time-domain measures
SDNN (ms)			<0.001
SDANN (ms)			0.008
ASDNN (ms)			0.037
RMSSD (ms)			0.360
pNN50 (%)			0.006

VLF: very low frequency; LF: low frequency; HF: high frequency; NN interval: normal to normal interval; SDNN: standard deviation of all NN intervals; SDANN: standard deviation of the averages of NN intervals; ASDNN: average standard deviation of the mean of every 5 min NN interval; RMSSD: square root of the mean of the sum of the squared differences between adjacent NN; NN50: number of pairs of adjacent NN intervals differing by >50 ms; pNN50: NN50 divided by the total number of all NN interval.