Exercise training and cardiac autonomic function following coronary artery bypass grafting: a systematic review and meta-analysis

The Egyptian Heart Journal

Table 2 An outline of all pooled data analysis for HRV and HRR measures

ANS measures	Studies included	No. of participants		SMD (95% CI)
ANS measures	Studies included	Exercise	Control	SMD (95% CI)
HRV
Time domain
SDNN	4	107	105	SMD 0.44 (0.17, 0.71), p = 0.002
SDANN	3	87	80	SMD 1.84 (− 0.11, 3.79), p = 0.07
RMSSD	3	57	55	SMD 0.68 (0.28, 1.08), p = 0.0008
Frequency domain
LF	3	79	80	SMD − 1.50 (− 1.10, 0.10), p = 0.10
HF	4	92	95	SMD 0.58 (0.18, 0.98), p = 0.005
LF/HF	3	79	80	SMD − 0.34 (− 0.65, − 0.02), p = 0.03
HRR₁	3	83	83	SMD 0.71 (0.39, 1.02), p < 0.0001