Heart rate variability analysis in Tibetan minipig. Control (Ctr, n = 4) and high-fat/cholesterol atherogenic diet minipigs (HFC, n = 6). (A) Heart rate, (B) standard deviation of all normal RR intervals (SDNN), (C) square root of the mean square successive differences between successive normal intervals (rMSSD), (D) total power (TP), (E) very low frequency (VLF) power, (F) low frequency (LF) power, (G) high frequency (HF) power, (H) LF/HF ratio, (I) graph of frequency domain analysis. Data are presented as mean ± SEM. a, P < 0.05 and b, P < 0.01 versus Ctr.