[Periodic breathing Cheyne-Stokes type, predict excessively reduced exercise tolerance in patients with chronic heart failure].

Introduction: Periodic breathing (PB) is evident during exercise in some patients with chronic heart failure (CHF) and is accompanied by hyperventilation.

Aim: To determine whether the presence of PB predicts excessive reduced exercise capacity in patients with severe CHF relative to patient with CHF of similar severity but with no PB.

Methods: Sixty-one CHF patients underwent cardiopulmonary exercise from 2009 to 2011 as part of their evaluation for cardiac transplantation. From this data, we selected patients in which the term "periodic breathing" appeared in their report. Matching patients with CHF without PB were identified from the same pool.

Results: Fifteen CHF patients with PB and 18 patients with CHF with similar ejection fraction but without PB (control) were identified from the pool of 61 patients. The PB group had a lower peak oxygen uptake related to body weight (VO2/ kg] and anaerobic threshold [AT) than the control group, by 30 +/- 11 and 39 +/- 4%, respectively (p < 0.05). The ventilatory equivalent for CO2 production (VE/VCO2) at the AT was higher and the end tidal pressure of CO2 (PETCO2) was lower in the control group as compared with the PB group (p < 0.05]. VE/ VCO2 at the AT was inversely correlated with peak VO2/kg [r = -0.45, p < 0.05].

Discussion: PB in patients with severe CHF is associated with excessively reduced exercise capacity. Increased ventilatory requirement may enhance dyspnea and may add to exercise limitation in these patients.

Conclusion: Periodic breathing reflects the severity of CHF and is associated with excessively reduced exercise tolerance in patients with CHF.