Dysfonction cardiaque autonome dans la maladie pulmonaire obstructive chronique. Récupération de la fréquence cardiaque après un exercice: facteur prédictif de mortalité dans la maladie pulmonaire obstructive chronique
Background. A delayed heart rate recovery (HRR = peak exercise heart rate (HR) – HR at 1-minute recovery) reflects cardiac autonomic dysfunction, which is associated with a poor prognosis. Purpose. To compare HRR between patients with chronic obstructive pulmonary disease (COPD) and controls; to compare survival in patients with COPD according to HRR; to evaluate survival influence of HRR modification following pulmonary rehabilitation. Methods and results. HRR was compared between 147 COPD patients and 25 controls (11±9 vs 19±9 beats, p<0.0001). In patients with COPD, abnormal HRR (?14 beats) was associated with a 5.12 mortality hazard ratio (CI 95% [1.54-17.00]). After pulmonary rehabilitation (n=77), persistent abnormal HRR represented a higher mortality risk (8.12; CI 95% [2.12-31.02]). Conclusions. HRR is decreased in COPD and, when abnormal, is linked with decreased survival. Persistent abnormal HRR after rehabilitation is associated with a poor prognosis.
Advisor:Maltais, François; Poirier, Paul
School Location:Canada - Quebec / Québec
Source Type:Master's Thesis
Date of Publication:04/01/2005