A 68-year-old man presents to the clinic with a 6-month history of severe daytime fatigue, non-restorative sleep, and frequent nighttime awakenings. His wife notes that his breathing during sleep is highly irregular, describing it as “stopping completely for almost a minute before starting up again with deep, loud breaths.” He denies snoring, choking, or gasping. His past medical history is significant for heart failure with reduced ejection fraction diagnosed 3 years ago following an anterior myocardial infarction. He is currently on guideline-directed medical therapy including a beta-blocker, an angiotensin receptor-neprilysin inhibitor, and a mineralocorticoid receptor antagonist. He denies the use of opioid medications or illicit drugs. He appears fatigued but is in no acute distress. His blood pressure is 112/70 mmHg, heart rate is 78 bpm, respiratory rate is 16 breaths per minute, and he is afebrile.