Noninvasive ventilation can modulate heart rate variability during high-intensity exercise in COPD-CHF patients

Objective: to assess the acute effects of non-invasive ventilation (NIV) during high-intensity exercise on heart rate variability (HRV) responses in chronic obstructive pulmonary disease (COPD) and Chronic heart failure (CHF) patients. Methods: This was randomized, double blinded and controlled study. Fourteen patients with COPD-HF diagnosis were evaluated. The subjects underwent to the following tests: (I) cardiopulmonary exercise testing (CPET) on a cycle ergometer ramp protocol; (II) 7 days after CPET, patients randomly underwent two constant-load exercise (CLE) with NIV or Sham ventilation until tolerance limit, with 80% of the CPET peak load. R-R intervals (RRi) were continuously collected during rest, exercise and in recovery. Time and frequency domain and nonlinear heart rate variability (HRV) indices were obtained. Results: NIV resulted in a decrease of Mean iRR, square root of the mean squared differences of successive RRi (rMSSD), RR tri index and high-frequency (HF), nu (p < 0.05) and increase of Mean HR, low-frequency (LF), nu and LF/HF (p < 0.05) during exercise when compared to rest. In addition, NIV during exercise induced lower rMSSD and Sample Entropy when compared with Sham (p < 0.05). Negative correlation was found between forced expiratory volume in 1 second (FEV1, L) vs HF (nu) during exercise with NIV (p = 0.04; r= -0.58). Furthermore, simple linear regression showed that the FEV1 (L) affected 30% of the HF (nu) response during the exercise with NIV. Conclusion: NIV during exercise produced enhanced heart rate and autonomic responses in COPD-CHF patients. Additionally, COPD severity is negatively associated with a higher vagal response during exercise with NIV. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

The study aimed to assess the acute effects of NIV during high-intensity exercise on HRV responses in COPD and CHF patients. The results showed that NIV led to changes in heart rate and autonomic responses, with COPD severity being negatively associated with vagal response during exercise with NIV.