The Nadir Oxygen-Specific Heart Rate Response in Sleep Apnea Links With the Occurrence of Acute Myocardial Infarction

Little is known regarding the quantification of sleep apnea- and hypoxemia-elicited heart rate (HR) response and its prognostic significance of the cardiovascular risk. We sought to explore the impact of HR response and variability specific to obstructive sleep apnea (OSA) on the occurrence of a common cardiovascular event - acute myocardial infarction (AMI). Consecutive patients with suspected OSA were enrolled and underwent nocturnal respiratory study and electrocardiography monitoring. The minimal oxygen saturation (minSpO ) was determined from the oxygen saturation curve under a subject-specific search window. Primary HR metrics such as maximal HR in response to minSpO and respiratory event-specific HR variability were computed from the synchronized recordings. Multivariate regression analyses were conducted to analyze the associations between individualized HR metrics and the occurrence of AMI. Of 2,748 patients recruited, 39% ( = 1,071) had moderate-to-severe OSA (respiratory event index, REI ≥ 15), and 11.4% ( = 313) patients had AMI. Patients with AMI experienced severe OSA, severe minSpO , and greater HR reactions. Patients with minSpO 73 bpm) was significantly associated with AMI (OR 1.72, 95% CI: 1.32-2.23, < 0.001). Patients with both severe minSpO (