Central Chemoreflex Sensitivity and Parasympathetic Nervous Activity in patients with Heart Failure

Although some studies point towards exacerbated central chemoreflex sensitivity (CCS) and reduced parasympathetic nervous activity (PNA) in patients with heart failure (HF), others dispute this finding by indicating their unchanging condition. The aim of this study is to compare CCS and PNA between patients with HF and healthy individuals. Eighteen patients with HF and 14 healthy individuals participated in the study. CCS was assessed through 7% CO2 rebreathing test for 4 minutes. PNA was determined based on Fast Fourier Transformation using the high-frequency component of heart rate variability. CCS was not different between HF patients [MD: 0.83 (0.49 to 1.54) l.min.mmHg] and healthy individuals [MD: 0.88 (0.16 to 2.56) l.min.mmHg]. PNA in HF patients [MD: 288 (266 to 1188) ms] also did not differ from healthy individuals [MD: 299 (81 to 1099) ms]. In conclusion, HF patients subjected to adequate clinical management may present preservation of CCS and PNA.