Sleep-disordered breathing and severe aortic stenosis

Abstract

Background

Aortic stenosis (AS) has been associated with sleep-disordered breathing (SDB), obstructive sleep apnea (OSA), and central sleep apnea (CSA). In patients undergoing transcatheter aortic valve implantation (TAVI), CSA may contribute to sudden cardiac death. Knowledge regarding complications and management of patients with TAVI and CSA is limited. This review defines the clinical manifestations of SDB, especially CSA, associated with AS and TAVI therapy. Prevalence, mechanisms, risk factors, and treatment options are reported.

Methods

Pubmed, Medline, and the Cochrane Database of Systematic Reviews were searched for prospective and retrospective studies, as well as case reports, in which SDB in AS was confirmed by polysomnography. Apnea was defined as a >90% reduction of airflow from baseline for >10 s; hypopnea as a >30% reduction in airflow with ≥4% O₂ desaturation; apnea–hypopnea index (AHI) as the number of apnea and hypopnea episodes/h of sleep. AHI >5/h defined SDB. If the recording showed more than 50% central apnea events, this was defined as CSA; otherwise as OSA.

Results

Five studies reporting on 299 patients were included. Patients with severe AS had a high prevalence of SDB (235/299; 78.6%). In AS patients, CSA had a prevalence of 105/251 (41.8%) and OSA of 93/248 (37.5%). Studies reported a strong association with SDB severity. TAVI for severe aortic valve stenosis improved CSA in two studies but had no impact on OSA. Positive airway pressure therapy appears the best treatment for CSA in patients with TAVI. Continuous positive airway pressure (CPAP) may be ineffective in eliminating central apnea or even increase CSA. Adaptive servo ventilation (ASV) and bilevel positive airway pressure (BPAP) ventilation are alternative treatments.

Conclusion

The prevalence of SDB in AS patients ranges from 71 to 95%. The most important risk factor for higher CSA severity in AS patients was heart failure (HF). ASV and CPAP have demonstrated efficacy in treating SDB in patients with HF. Limited data and clinical experience are available for ASV treatment of patients with AS-associated SDB. Prospective studies on quality life and ASV treatment in these patients are needed.

http://ift.tt/2pzdOGR