The effect of mandibular advancement device on pharyngeal airway dimension in patients with congestive heart failure treated for sleep apnoea.

Continues positive airway pressure (CPAP) is recommended for treatment of sleep apnoea (SA) in patients with congestive heart failure (CHF) but is not easily tolerated resulting in poor patient compliance. Mandibular advancement device (MAD) is designed to inhibit pharyngeal airway (PAW) obstruction and may be a valuable alternative. It has been proposed that MAD exerts its effect by increasing PAW dimensions. This has not, however, been clearly demonstrated. The aim of this study was to examine the effect of MAD on PAW dimensions and SA in patients with CHF. Seventeen CHF-patients with mild to moderate heart failure, aged 68 +/- 6 years, (mean +/- SD), range 54-75 years, with sleep apnoea-hypopnea index (AHI) > or = 10 were evaluated. PAW dimensions were studied with and without the MAD, using lateral radiographs in supine position. Nocturnal breathing patterns were studied using a portable polysomnographic device during a single night with and without MAD. A reduction of AHI > or = 30% (arbitrary level) for each individual was regarded as a successful treatment. Mean AHI was reduced from 25.1 +/- 9.4 to 14.7 +/- 9.7 (p = 0.003). The PAW increased in its inferior section in 13 patients (p = 0.0001). AHI decreased > or = 30% in 9 patients (p = 0.003) of whom 8 showed increased PAW dimensions. Reduction of AHI was not significantly related to increased PAW dimensions. In conclusion MAD increased PAW dimensions and reduced SA in patients with CHF. The results may indicate that MAD reduces SA by other mechanism than increasing PAW dimensions.