Hosts Mitsuaki Sawano, MD, and Shun Kohsaka, MD welcome Dr. Suguru Araki, MD and Dr. Satoshi Nakamura, MD (Mie University) to discuss their JACC: Cardiovascular Imaging study, “Validation of Ultra-Low-Dose Coronary Artery Calcium Scoring Using Photon-Counting Computed Tomography.” As cardiac CT becomes increasingly central to cardiovascular diagnosis and prevention, radiation exposure remains an important concern, especially in Japan, one of the world’s most CT-intensive countries. This episode explores how photon-counting CT, combined with Sn100 kVp high-pitch acquisition and 65 keV virtual monochromatic imaging, enabled coronary artery calcium scoring at nearly one-ninth the radiation dose of standard scanning while preserving Agatston score accuracy. The discussion highlights how ultra-low-dose CAC scanning may fit into future preventive cardiology, screening, and cardiac CT workflows while maintaining compatibility with established risk stratification methods.