061: Short- and long-term effects of nocturnal oxygen therapy on sleep apnea in chronic heart failure

Abstract

To study short- and long-term effects of nocturnal oxygen therapy (NOT) on sleep apnea (SA) in chronic heart failure (CHF). In 51 consecutive stable CHF patients, NYHA II/III, left ventricular ejection fraction (LVEF) ≤45%, baseline nocturnal ventilation polygraphy identified 33 SA patients (apnea-hypopnea index (AHI) ≥15 events/h) who were randomized to receive NOT 3 L/min (n=19) or no NOT (n=14). NOT was applied for 6 months with a home concentrator, the first night with polygraphy. Sixteen patients with NOT and 14 without NOT had polygraphy after 6 months. In patients without NOT, there was no significant difference between baseline and the sixth month. In NOT patients, a marked AHI reduction was observed between baseline versus the first night and the sixth month, respectively, 36.8±2.6 versus 20.8±3.0 and 18.3±2.4 events/h (p<0.0001) and related to a central AHI decrease, respectively, 23.3±2.8 versus 8.3±1.6 and 6.1±1.4 events/h (p<0.0001). The oxygen desaturation index (ODI) evolved similarly: 33.0±5.2 versus 7.5±0.5 and 9.3±2.6 events/h (p<0.0001). NOT had no effects on obstructive and mixed AHI. In NOT patients versus those without, respectively, AHI decreased by 49.0±6.0% versus increased by 2.0±14.0% (p<0.0001), ODI decreased by 59.0±9.4% versus 6.4±14.7% (p=0.004), SaO 2 <90% time decreased by 61.4±9.9% versus increased by 60.0±68.4% (p=0.1) and LVEF increased by 14.5±10.2% versus 5.6±16.1% (p=0.6). In stable CHF patients, NOT significantly reduced central AHI and ODI, with acute effects being sustained over time and impacting neither obstructive and mixed AHI nor daytime LVEF.