Introduction Patients with advanced aortic stenosis (AS) have a high risk of sleep-related breathing disorders (SRBD), yet prior research is limited to type III sleep apnea tests. Whereas the American Academy of Sleep Medicine recommends polysomnography for SRBD diagnosis in patients with significant cardiorespiratory disease, unattended studies are often more acceptable, especially to surgical candidates. We conducted this study to address the need for comprehensive sleep testing in patients with advanced AS. Methods We conducted unattended type II sleep tests in 23 adults aged 50 and older scheduled for surgical aortic valve replacement (SAVR) and not using positive airway pressure. We obtained demographics and medical history and administered Clinical Dementia Rating, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, and 9-item Patient Health Questionnaire. We characterize this pre-surgical sample and report SRBD prevalence. Results Average age of the sample was 68.3 ± 7.2 (mean ± SD), and 74% were male. Charlson comorbidity index was 2.0 ± 2.0. Three (13%) had a global CDR of 0.5, consistent with mild cognitive impairment. Mean PSQI scores were 7.0 ± 3.6, ESS 6.7 ± 4.0, and PHQ-9 4.6 ± 5.3. No subject had an AHI < 5: 7 had a score of 5–14, 8 of 15–29, and 8 of 30 or greater. Mean obstructive AHI was 25.3 ± 20.7, central AHI 1.9 ± 3.4, and respiratory arousal index 8.7 ± 6.2. Total sleep time 362.7 ± 82.6 min with sleep efficiency of 82.1% ± 8.6%. Sleep stage data to be presented. Conclusion All subjects in this sample not using positive airway pressure had an AHI ≥ 5. Sixteen subjects (70%) had an AHI ≥ 15, indicating moderate to severe sleep apnea due to predominantly obstructive events. These results strongly suggest that patients with severe AS, especially those undergoing SAVR, would benefit from evaluation for SRBD. Support (if any) This research was supported in part by the National Institute on Aging, K23AG072383. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Additional support provided by University of Rochester Medical Center funds through the Departments of Psychiatry and Cardiology/Cardiac Surgery.