Resumo

GUTIERREZ SOTELO, Oswaldo. Variabilidad de la frecuencia cardíaca en individuos sanos costarricenses. Rev. costarric. cardiol [online]. 2000, vol.2, n.1, pp.2-10. ISSN 1409-4142.

Introduction. Heart rate variability analysis evaluate the autonomic influence over the heart and therefore, is a predictive tool of mortality. It consists in the analysis of the variations in RR intervals. This study assessed heart rate variability in healthy costarrican people. Materials and Methods. We included adult healthy volunteers. For data adquisition we used a single electrocardiographic lead and calculate time and frequency domain variables. We compared results between 5 minutes versus 10 minutes samples and between age groups: 18 to 29 years old, versus 30 to 39 versus 40 or < 25 years old versus 25. Results. We studied 48 subjects, 25 women and 23 men (range 18 y 53). We do not obtained differences between time of data adquisition samples but find differences between 18-29 vs 40 and <25 vs 25 age groups in NN50 (231.432 vs 34.500, p = 0.004 in the fisrt group, 237.250 vs 53.250, p<0.001, the second, %NN50 (30.732 vs 5.2, p=0.003 and 31.444 vs 9.742, p=0.001 respectively, LF (457.338 vs 173.393, p=0.045 and 466.816 vs 259.361, p=0.042 respectively) and HF (750.667 vs 239.865, p=0.068 and 766.834 vs 248.436, p=0.010 respectively). Conclusions. This study support reference values for comparision or to individual autonomic tone evaluation. Differences between distant age groups suggest that aging increases progressively simpathetic tone over parasimpathetic tone or a decrease in bands of the spectrum. This hypotesis need further investigation.

Palavras-chave : Autonomic Tone; Heart Rate Variability; Aging.