Oxygen therapy prevents ventricular arrhythmias in patients with congestive heart failure and sleep apnea

Background Although ventricular arrhythmia is critical for the prognosis of patients with severe congestive heart failure (CHF), it is difficult to control the arrhythmia using conservative therapies. However, many CHF patients also have sleep apnea syndrome (SAS) and oxygen supply improves their prognosis. The beneficial effects of oxygen treatment for ventricular arrhythmia have not yet been clarified, so the present study was designed to evaluate the effects of oxygen treatment for premature ventricular contraction (PVC). Methods and Results Patients with CHF and SAS were divided into 3 groups: (1) the "PVC declined" group that included patients who had frequent PVCs and oxygen treatment that suppressed the number of PVC; (2) the "PVC not affected" group that included patients who had frequent PVCs and oxygen treatment did not affect the number of PVC; and (3) the "few PVC" group that included patients who had no or few PVCs. The group I patients showed higher apnea-hypopnea index, standard deviation of all R-R intervals, left ventricular ejection fraction, and brain natriuretic peptide levels than the patients in group 2. Oxygen treatment in group 3 did not affect the PVC frequency. Conclusions Oxygen treatment may be useful for preventing ventricular arrhythmia in selected patients with CHFandSAS.