Abstract
Background: Multiple factors (airflow limitation, hypoxemia, inflammation, arterial stiffness) may be associated with cardiac dysautonomia in patients with bronchiectasis. However, cardiac autonomic modulation has never been investigated in these patients.
Objective: To investigate if there is abnormal heart rate variability (HRV) in bronchiectasis patients.
Methods: Thirty-two patients with bronchiectasis (11 men,46±15 yrs, FEV1 60±20 %pred) and 9 age-matched healthy subjects (3 men,39±11 yrs, FEV1 99±15 %pred) were evaluated. The R-R interval was continuously recorded using a Polar® S-810i at rest (20') for HRV analysis (FFT). They underwent spirometry, shuttle walk test (SWT), cardiopulmonary exercise testing.
Results: Cadiac sympathovagal balance (LF/HF) was higher in cases than in control group [1.7(1.2−2.9) vs. 1.1(0.8−1.3), p=0.007] and LF as well. LF/HF showed a negative correlation with FEV1/FVC (r= -0.42,p=0.02). Patients with worst pulmonary function (FEV1 < 50%) showed higher LF/HF and heart rate (HR) at rest. A positive correlation was observed between LF/HF and HR at rest on SWT (r = 0.44,p=0.012), with recovery HR in the second minute of the SWT (r = 0.38, p = 0.036), and a trend with the delta of desaturation on SWT (r = -0.37, p = 0.09). There was a trend for a correlation between LF/HF and peak workload (%pred, r = -0.31,p = 0.086), and no correlation with other variables (VO2 and distance walked on ST).
Conclusion: Patients with bronchiectasis may present impaired cardiac autonomic modulation. Reduced lung function is related to sympathetic overactivity, suggesting increased cardiorespiratory risk. Future studies should evaluate the impact of these findings on morbidity and mortality in this population.
- Copyright ©ERS 2015