title: Spectral analysis related to bare-metal and drug-eluting coronary stent implantation.
abstract: BACKGROUND
  The autonomic nervous system plays a central role in cardiovascular regulation; sympathetic activation occurs during myocardial ischemia.
  
  
  OBJECTIVE
  To assess the spectral analysis of heart rate variability during stent implantation, comparing the types of stent.
  
  
  METHODS
  This study assessed 61 patients (mean age, 64.0 years; 35 men) with ischemic heart disease and indication for stenting. Stent implantation was performed under Holter monitoring to record the spectral analysis of heart rate variability (Fourier transform), measuring the low-frequency (LF) and high-frequency (HF) components, and the LF/HF ratio before and during the procedure.
  
  
  RESULTS
  Bare-metal stent was implanted in 34 patients, while the others received drug-eluting stents. The right coronary artery was approached in 21 patients, the left anterior descending, in 28, and the circumflex, in 9. As compared with the pre-stenting period, all patients showed an increase in LF and HF during stent implantation (658 versus 185 ms2, p = 0.00; 322 versus 121, p = 0.00, respectively), with no change in LF/HF. During stent implantation, LF was 864 ms2 in patients with bare-metal stents, and 398 ms2 in those with drug-eluting stents (p = 0.00). The spectral analysis of heart rate variability showed no association with diabetes mellitus, family history, clinical presentation, beta-blockers, age, and vessel or its segment.
  
  
  CONCLUSIONS
  Stent implantation resulted in concomitant sympathetic and vagal activations. Diabetes mellitus, use of beta-blockers, and the vessel approached showed no influence on the spectral analysis of heart rate variability. Sympathetic activation was lower during the implantation of drug-eluting stents.
authors.affiliation: Faculdade de Medicina da UFMG, Divinópolis, MG, Brazil.
authors.forename: Rose Mary Ferreira Lisboa da
authors.initials: RM
authors.lastname: Silva
authors.affiliation: Faculdade de Medicina da UFMG, Divinópolis, MG, Brazil.
authors.forename: Carlos Augusto Bueno
authors.initials: CA
authors.lastname: Silva
authors.affiliation: Hospital São João de Deus, Divinópolis, MG, Brazil.
authors.forename: Otaviano José
authors.initials: OJ
authors.lastname: Greco
authors.affiliation: Faculdade de Medicina da UFMG, Divinópolis, MG, Brazil.
authors.forename: Maria da Consolação Vieira
authors.initials: Mda C
authors.lastname: Moreira
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005583:Fourier Analysis; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000601:surgery*; D062645:Percutaneous Coronary Intervention / Q000379:methods*; D011446:Prospective Studies; D012016:Reference Values; D018709:Statistics, Nonparametric; D015607:Stents; D013564:Sympathetic Nervous System / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome