The RICCADSA Legacy: Two Decades of Research on Obstructive Sleep Apnea, Coronary Artery Disease, and CPAP Therapy

Abstract Purpose of Review Obstructive sleep apnea (OSA) is highly prevalent among patients with coronary artery disease (CAD) and has been implicated in adverse cardiovascular outcomes through multiple pathophysiological pathways. The Randomized Intervention with Continuous Positive Airway Pressure in Coronary Artery Disease and Sleep Apnea (RICCADSA) project was initiated to investigate the prevalence, clinical significance, and treatment implications of OSA in patients with revascularized CAD. This review summarizes the major scientific contributions of the RICCADSA project over the past two decades and discusses their impact on contemporary cardiovascular sleep medicine. Recent Findings RICCADSA demonstrated that OSA is highly prevalent among participants with CAD and provided important mechanistic insights linking OSA to systemic inflammation, myocardial dysfunction, autonomic dysregulation, endothelial and vascular biology, and adverse cardiovascular outcomes. Although the primary randomized trial did not demonstrate a significant reduction in cardiovascular events with routine continuous positive airway pressure (CPAP) treatment in nonsleepy participants, subsequent analyses identified treatment-responsive subgroups based on adherence, excessive daytime sleepiness, physiological traits, autonomic responses, hypoxic burden, and endothelial phenotypes. More recent investigations have highlighted the limitations of conventional severity metrics such as the apnea–hypopnea index and supported the emerging role of biological and physiological phenotyping in cardiovascular risk stratification. Summary Over the past twenty years, the RICCADSA project has evolved from a randomized clinical trial into a comprehensive research platform that has helped shape current understanding of OSA and cardiovascular disease. Its findings have contributed to a transition from an AHI-centered approach toward precision sleep cardiology, emphasizing the biological heterogeneity of OSA and the need for individualized treatment strategies to optimize cardiovascular outcomes.