title: Heart rate variations in chronic obstructive pulmonary disease.
abstract: Autonomic nervous system dysfunction proved in chronic obstructive pulmonary disease (COPD) patients might determine an elevated cardiovascular risk by heart rate alteration.
  
  
  OBJECTIVE
  To assess the particularities of heart rate as a possible cardiovascular risk factor in COPD patients.
  
  
  METHODS
  This prospective, case-control study comparatively analyzed the pulse rate continuously recorded with a polygraph in 32 COPD patients and 29 healthy subjects during rest (supine and sitting position) and during submaximal exercise (6-minute walk test). The relation between pulse rate and respiratory, functional or clinical alterations was analyzed in COPD patients.
  
  
  RESULTS
  The mean pulse rate was significantly higher during rest and exercise in COPD patients compared with the controls. However, the chronotropic response determined by exercise was similar in COPD and control groups: 55.19 beats/minute and 57.21 beats/minute, respectively (p=0.686). The mean pulse rate during exercise correlated with hypoxemia (r=-0.354, p=0.47) and with resting pulse rate (r=0.871, p<0.001 for supine position).
  
  
  CONCLUSIONS
  COPD associates elevated pulse rates during both rest and exercise. Hypoxemia and resting pulse rate are determinatives of chronotropic response during submaximal exercise in COPD patients.
authors: University of Medicine and Pharmacy Grigore T. Popa, lasi.
authors: M
authors: M
authors: Roca
authors: Discipline of Medical Semiology, University of Medicine and Pharmacy Grigore T. Popa, lasi.
authors: F
authors: F
authors: Mitu
authors: Discipline of Emergency Medicine, University of Medicine and Pharmacy Grigore T. Popa, lasi.
authors: Iulia-Cristina
authors: IC
authors: Roca
authors: Discipline of Pneumology, University of Medicine and Pharmacy Grigore T. Popa, lasi.
authors: T
authors: T
authors: Mihăescu
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D016022:Case-Control Studies; D003324:Coronary Artery Disease / Q000150:complications; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D012146:Rest; D018570:Risk Assessment; D012307:Risk Factors; D017678:Sex Distribution; D012907:Smoking / Q000009:adverse effects