Can Fractional Flow Reserve-Computed Tomography (FFR-CT) Overestimate the Severity of Coronary Stenoses in the Presence of High Calcium Burden?

Non-invasive diagnostic methods such as coronary artery calcium (CAC) scoring, computed tomography angiography (CTA), and fractional flow reserve-computed tomography (FFR-CT) are useful to predict the presence of coronary artery stenosis, but may provide false positive results as well. This case describes a man in his mid-60s with significant cardiac history who presented to the emergency department with chest pain. Extensive workup included CTA, which demonstrated severe coronary artery calcification and abnormal FFR-CT suggestive of severe three-vessel disease. Urgent invasive coronary angiography was performed due to his high likelihood of flow-limiting stenosis; however, it revealed only mild-to-moderate non-obstructive (<50%) stenoses. This report highlights the potential of CAC, CTA, and FFR-CT to overestimate the severity of coronary artery disease.