Review in coronary functional evaluation methods: applications of computational fluid dynamics and artificial intelligence in the context of coronary artery disease

Coronary artery disease, driven by the progressive accumulation of atherosclerotic plaque within the epicardial coronary arteries, remains a leading cause of myocardial ischemia and global morbidity. A fundamental challenge in the clinical management of the disease has been the reliance on anatomic stenosis severity alone, a metric that frequently dissociates from the hemodynamic significance of a lesion and thus offers limited guidance for optimal revascularization. The advent of invasive measurements marked a transformative paradigm shift, enabling the development of a diverse functional indices for the evaluation of coronary physiology. Recently, the development of computational science and artificial intelligence has accelerated the translation of these physiological assessments into the non-invasive domain, primarily through high-fidelity numerical simulations and efficient machine learning algorithms. This review systematically examines the evolution of coronary functional assessment across several pivotal frontiers. It begins by contextualizing the diagnostic landscape prior to the widespread adoption of functional indices, where clinical decisions were predominantly informed by imaging-derived anatomical parameters. Subsequently, it traces the historical evolution of invasive coronary functional indices, critically evaluating the comparative effectiveness of pressure-derived metrics against flow-derived metrics in the detection of hemodynamically significant ischemia. Furthermore, a critical evaluation of emerging artificial intelligence methodologies for the non-invasive evaluation of functional significance were employed. By synthesizing these technological methodologies, this review aims to elucidate the appropriate clinical application of each functional index, thereby providing a road-map for clinicians to achieve precise, individualized ischemia evaluation and guide therapeutic decision-making in the contemporary era of precision cardiovascular medicine.