Percutaneous coronary intervention (PCI) is safer than ever, yet coronary hematoma remains an underrecognized cause of early ischemic complications. In this episode, Host Mitsuaki Sawano, MD welcome Takunori Tsukui, MD and Akiko Maehara, MD to discuss their JACC: Cardiovascular Interventions study comparing 22 event-causing hematomas with 80 event-free hematomas identified from more than 3,000 IVUS-guided PCI procedures. The conversation explores how IVUS can distinguish high-risk from low-risk post-PCI hematomas, the imaging features associated with progression, and how these findings may help operators decide when additional stenting is necessary—and when careful observation may be the better strategy.

Pediatric heart transplantation is one of medicine's scarcest resources, where every allocation decision can mean the difference between life and death. But does the current system truly prioritize the children at greatest risk? Hosts Mitsuaki Sawano, MD, and Satoshi Shoji, MD welcome Kazunari Sasaki, MD (Stanford University) to discuss his JACC study, Status Exceptions and Misalignment of Medical Urgency in U.S. Pediatric Heart Transplantation. Using the national OPTN registry of more than 6,000 children awaiting heart transplantation, the study examines whether "status exceptions"—special requests to elevate transplant priority—accurately reflect medical urgency and whether the National Heart Review Board has improved the fairness of organ allocation. The episode explores why well-intentioned exception requests may unintentionally disadvantage the sickest children, how waiting-list mortality varies dramatically within the highest priority category, and why objective measures of medical urgency may be needed to improve equity in donor heart allocation. Dr. Sasaki also shares insights into the evolution of the U.S. transplant system, emerging innovations such as ex vivo heart perfusion, and how data-driven policy can shape the future of pediatric transplantation.

Premature atrial complexes (PACs) are among the most common arrhythmias encountered in daily practice and are often dismissed as benign. But are they truly harmless—or could some represent the earliest stage of atrial fibrillation (AF)? Hosts Mitsuaki Sawano, MD, and Hiroyuki Sato, MD welcome Satoshi Higuchi, MD (Tokyo Women's Medical University) to discuss his JACC: Clinical Electrophysiology study, Atrial Effective Refractory Periods in Patients With Frequent Premature Atrial Complexes: Implications for Atrial Fibrillation. Building on translational work from experimental models, the study compares atrial effective refractory periods (AERP) in patients with frequent PACs, paroxysmal AF, and persistent AF to better define the electrophysiologic substrate underlying these conditions. The episode explores how electrical remodeling differs between PACs and AF, why pulmonary vein AERP shortens before more diffuse atrial remodeling develops, and what these findings reveal about the progression from atrial ectopy to sustained arrhythmia. The discussion also examines the emerging concept of PAC-induced atrial cardiomyopathy, the challenge of distinguishing "benign" from potentially malignant PACs, and the future of risk stratification and preventive intervention before AF becomes established.