In a cohort of patients with suspected myocardial ischemia undergoing sleep studies, the objectives of this study were:
1. To determine the association between various obstructive sleep apnea (OSA)-related nocturnal hypoxemia parameters and coronary microvascular dysfunction (CMD) in patients with suspected myocardial ischemia. 2. To compare the predictive value of nocturnal hypoxemia parameters versus the traditional Apnea-Hypopnea Index (AHI) for coronary microvascular dysfunction. 3. To evaluate the prognostic value of nocturnal hypoxemia parameters in predicting Major Adverse Cardiovascular Events (MACE) during the follow-up period. 4. To explore the potential mediating roles of inflammatory and oxidative stress biomarkers in the relationship between nocturnal hypoxemia parameters and coronary microvascular dysfunction.
Aged 18 to 80 years, of any gender.
Scheduled for elective coronary angiography due to symptoms or evidence of myocardial ischemia.
Agreed to and capable of completing overnight polysomnography (PSG) monitoring.
Provided written informed consent and were willing and able to comply with baseline assessments and long-term follow-up.
Presence of coronary chronic total occlusion (CTO), history of coronary artery bypass grafting (CABG), severe valvular heart disease, dilated or hypertrophic cardiomyopathy, congenital heart disease, or heart failure (NYHA functional class III-IV).
Sleep-disordered breathing with central sleep apnea (CSA) as the primary manifestation.
Severe hepatic insufficiency (Child-Pugh class C) or renal failure (eGFR < 30 mL/min/1.73 m²).
Pregnancy or lactation.