Coronary artery disease remains the leading cause of death globally, demanding more accurate, accessible, and patient-friendly diagnostic tools. This white paper presents VCAST, an AI-powered, non-invasive system that uses CT imaging and computational fluid dynamics (CFD) to deliver precise Fractional Flow Reserve (FFR) assessments without the need for catheterization. It explores the clinical rationale, technological foundation, and real-world validation of VCAST, highlighting how it enhances diagnostic accuracy, reduces healthcare costs, and improves patient experience.