Severe aortic valve stenosis in the elderly: high prevalence of sleep-related breathing disorders

Aortic valve stenosis is common in the elderly, with a prevalence of nearly 3% in patients aged 75 years or older. Despite the fact that sleep-related breathing disorders (SRBD) are thought to be associated with cardiac disease, little is known about their prevalence in this patient cohort. The purpose of this study was to evaluate the prevalence of SRBD in older patients with aortic valve stenosis admitted for transcatheter aortic valve implantation.

Forty-eight consecutive patients (mean age 81±6 years; 37.5% male) with symptomatic aortic valve stenosis and considered for transcatheter aortic valve replacement were screened for SRBD. Sleep studies were performed by in-hospital unattended cardiorespiratory polygraphy measuring nasal air flow, chest and abdominal efforts, as well as oxygen saturation and body position. The patients were divided in subgroups dependent on the documented apnea-hypopnea index (AHI; no SRBD was defined as an AHI of <5 events/hour; mild SRBD as AHI 5-15 events/hour, and moderate to severe SRBD as AHI ≥15 events/hour).

Thirty-seven patients (77%) had SRBD defined as an AHI of ≥5 events/hour. Eleven patients had an unremarkable investigation, with AHI <5 events/hour (mean 3.0±1.3 events/hour). Among patients with sleep apnea, 19 patients had mild SRBD, with an AHI of 5-15 events/hour (mean 9.9±3.4 events/hour) and 18 patients had moderate to severe SRBD (mean 26.6±11.3 events/hour). Mainly, obstructive apneas were found. Subgroups were not different regarding EuroSCORE (European System for Cardiac Operative Risk Evaluation) or aortic valve area. Also, no correlations were found between AHI and the additive or logistic EuroSCORE or aortic valve area. Significant correlations were found for AHI and N-terminal of the prohormone brain natriuretic peptide (r=0.53; P=0.003) and for AHI and glomerular filtration rate (r = -0.39; P=0.007).

SRBD is common in elderly patients with symptomatic aortic valve stenosis admitted for transcatheter aortic valve replacement. Interestingly, this finding is not reflected by the currently used risk scores. Further randomized studies are needed to evaluate the clinical significance of concomitant SRBD in the management of severe aortic stenosis.