Aims: Severe cardiac disorders predispose to central sleep apnoea (CSA). We sought to examine the relationship between severe aortic stenosis, sleep disordered breathing (SDB), and CSA before and after transcatheter aortic valve implantation (TAVI).
Methods and results: Twenty-nine patients (81±6 yrs, 41% male, LVEF 48±14%) with severe aortic stenosis and high surgical risk underwent polygraphy before and three months after TAVI. Patients with an apnoea-hypopnoea index (AHI) >5/hr were considered to have SDB. SDB with ≥50% absence of both airflow and ventilatory effort was defined as CSA. Twenty-one of 29 patients (72%) had SDB (6/6/9 mild, moderate, and severe, respectively), 12 (41%) with CSA (0/4/8) and 9 (31%) with obstructive sleep apnoea (7/2/0). There was a strong correlation of CSA with LVEDP before TAVI (r=0.74, p=0.024), but not with LVEF, systolic pulmonary artery pressure or NT pro-BNP. After TAVI, AHI improved significantly, particularly in the CSA group (from 43.5±17.5 to 19.4±12.9/hr, p<0.001). Prevalence and severity of SDB were reduced from 72% to 59% (6/6/9 to 7/8/2 patients), triggered by the significant improvement of CSA.
Conclusions: Patients with severe aortic stenosis display a high prevalence of SDB, particularly of CSA. Definitive treatment with TAVI greatly resolved SDB in the CSA subgroup.