Background: Spectrum analysis of heart rate variability (HRV) is a noninvasive procedure that provides information on sympathetic and parasympathetic controls. Reduced HRV may indicate cardiac autonomic dysfunction and susceptibility to hemodynamic instability during anesthesia, after myocardial infarction or cardiac operations. Aim: This study was designed to investigate the effects of cardiopulmonary bypass on HRV variability in children with congenital heart disease and if HRV is turning to the normal in postoperative period and when, as well as the duration of the process. Methods: HRV data were obtained from 29 pediatric patients with congenital heart disease, who underwent elective cardiac surgery. Electrocardiographic data were collected with PC-based ECG acquisition system (PC-ECG 1200). ECG results were obtained by assessing 200 heart beats that recorded in supine position. Clinical data including age, type of cardiac lesion, type of surgical procedure, cardiopulmonary bypass (CPB) time, cross clamp time were recorded. Results: 16 male and 13 female patients mean aged 8.08±3.8 (1-15), 27 had an acyanotic heart disease, 2 of them had a cyanotic heart disease. Standard deviation of all normal RR intervals (SDNN) (p=0.048) and HRV triangular index (p=0.017) were significantly lower in the postoperative first month than preoperatively. There were no significant preoperative differences in other time or frequency domain measures of HRV between the preoperative recordings and postoperative for the first month. SDNN, low and high frequency were found significantly low when compared between the postoperative first and third month, although HF was decreased in the first postoperative month, but did not reach statistical significance. Conclusion: Our findings showed that decreased HRV is a nonspecific marker of cardiovascular stress just after the cardiac operations, reflecting an alteration in autonomic nervous system input to the heart and turning to the normal in the third month.
Murat Özeren, Olgu HallIo Lu, Khatuna Makharoblidze, Handan AnkaralI, Heart Rate Variability in Children with Congenital Heart Disease Before and After Open Heart Surgery Journal of the Hong Kong College of Cardiology 2009;17(2) https://doi.org/10.55503/2790-6744.1091