Impact of obstructive sleep apnea severity on coronary plaque complexity and ventricular function in patients with suspected coronary artery disease

Background Obstructive sleep apnea (OSA) is a multifaceted sleep disorder that triggers systemic inflammation and oxidative stress, potentially accelerating coronary atherosclerosis. While its role as a risk factor is established, the direct correlation between OSA-related hypoxic burden and the anatomical complexity of coronary lesions remains under-researched. This study evaluated whether OSA severity independently predicts high-risk coronary anatomy as defined by the SYNTAX score. Methods We prospectively enrolled 103 patients (mean age 68 years) referred for invasive coronary angiography. All participants underwent Type III respiratory polygraphy during hospitalization. The Apnea-Hypopnea Index (AHI), Oxygen Desaturation Index (ODI), and mean oxygen desaturation were recorded. Coronary lesion complexity was quantified using the SYNTAX score. Detailed echocardiography assessed left ventricular ejection fraction (LVEF) and diastolic parameters (E' septal/lateral). Results Significant coronary artery disease (CAD) was diagnosed in 74.8% of patients. These individuals showed significantly higher median AHI (18.8 vs 13.5; p=0.003) and ODI (19.3 vs 12.9; p=0.003) compared to those without significant CAD. Severe OSA was observed in 36.4% of the CAD group vs only 3.8% in the non-CAD group (p=0.003). LVEF was significantly reduced in the CAD group (55% vs 61%; p=0.002). Multivariate linear regression confirmed AHI as a robust independent predictor of higher SYNTAX scores (β=0.376; p=0.005) after adjusting for sex, age, and systemic inflammation (hsCRP). Additionally, a STOP-BANG score >3 points was associated with a 3.27-fold increase in the likelihood of significant CAD (OR 3.27, 95% CI 1.27–8.43, p=0.014). Conclusions Increased OSA severity is independently associated with higher anatomical complexity of CAD and impaired left ventricular function. These findings suggest that sleep-disordered breathing may serve as a marker for high-burden coronary atherosclerosis. Systematic screening using the STOP-BANG tool in cardiology departments may identify patients who require intensive cardiovascular risk management and OSA therapy to potentially mitigate further plaque progression.