Heart rate variation analysis may not effectively detect sleep apnoeas in heart failure.

In a recent issue of the European Respiratory Journal, VAZIR et al. [1] demonstrated that spectral analysis of heart rate variations (HRV) may be useful as a ‘‘rule-out test’’ for sleep-disordered breathing (SDB) in patients with mild-to-moderate congestive heart failure (CHF). This is an interesting approach to the diagnosis of SDB in CHF patients without sleepiness. As CHF patients with Cheyne–Stokes respiration (CSR)/central sleep apnoea (CSA) are often asymptomatic, this noninvasive approach may be effective to rule out SDB in patients. However, we feel that there are a number of problems with the article by VAZIR et al. [1].