Portable Smartphone-Based Thermal Imaging for Real-Time Assessment of Coronary Artery Bypass Grafting Graft Patency and Cardioplegia Distribution: A Feasibility Case Series

INTRODUCTION: Intraoperative assessment of graft patency and cardioplegia distribution during coronary artery bypass grafting (CABG) is essential for surgical success but remains challenging in resource-limited settings. Conventional tools such as flow measurement or intraoperative angiography are often unavailable in public hospitals, where evaluation relies mainly on clinical judgment. METHODS: We conducted a prospective observational case series of 10 CABG patients operated between February and July 2025 at a public university hospital. Myocardial temperature distribution during cardioplegia infusion and after grafting was monitored with a portable smartphone-based thermal camera (FLIR One Pro). RESULTS: Thermal imaging documented cardioplegia distribution and graft patency in all cases. In one patient, heterogeneous distribution in the lateral wall was identified, leading to a change in surgical sequence and improved myocardial protection. All patients were weaned from bypass with stable rhythm, showed expected postoperative troponin kinetics, and had no new wall motion abnormalities on echocardiography. CONCLUSION: Portable thermal imaging is a feasible, safe, and inexpensive method for real-time intraoperative evaluation of cardioplegia distribution and graft patency in CABG. It may represent a valuable adjunct in resource-limited environments. Larger studies are needed to confirm these findings.