[Effects of home oxygen therapy on patients with chronic heart failure]

Dyspnea on exertion and/or hypoxemia due to nocturnal respiratory disturbance may occur in patients with stable chronic congestive heart failure. Such patients with respiratory disorder during sleep have a poor prognosis. The effects of treatment with home oxygen therapy on patients with congestive heart failure are unclear when symptoms are stable at rest. This study investigated the effects of home oxygen therapy on patients with stable chronic congestive heart failure.

Thirty-three patients with stable chronic congestive heart failure(New York Heart Association functional class II-IV) and hypoxemia during exercise or sleep were treated with oxygen above the level of 90% SaO2. The following factors were compared before and after home oxygen therapy: Subjective minimal capacity on exercise(metabolic equivalents: METs) before and 1 month after patients first became aware of dyspnea on effort using the specific activity scale(SAS); SaO2 at rest before and 1 month after; and frequency of admission during 1 year due to deterioration of heart failure.

After home oxygen therapy, SAS improved from 2.5 +/- 0.9 to 3.3 +/- 1.0 METs(p < 0.0001), and SaO2 at rest improved from 92.8 +/- 2.5% to 96.3 +/- 1.6%(p < 0.0001). The frequency of admission was decreased from 1.3 +/- 1.2 to 0.8 +/- 1.2 times(p = 0.03).

Home oxygen therapy is effective for improving the symptoms and activity of daily life in patients with chronic heart failure. Home oxygen therapy may prevent the deterioration of heart failure.