This study evaluated the influence of coronary artery bypass grafting on heart rate turbulence (HRT) parameters assessed during 1-year follow-up in patients with coronary artery disease. HRT and heart rate variability (HRV) parameters significantly worsened 3 months after surgery. After 1 year, HRV parameters and turbulence onset returned to preoperative values, whereas turbulence slope remained significantly attenuated. Our results show that there is a marked attenuation of HRT parameters in the early postoperative period, indicating an impairment of baroreflex sensitivity after coronary artery bypass grafting. Concomitant depression of HRV parameters points to dysfunction of the autonomic nervous system, provoked by perioperative attenuation, as a potential underlying cause of impaired baroreflex response.