Evaluation of epicardial coronary resistance using computed tomography angiography

Abstract Aims Fractional flow reserve (FFR) pullback allows to assess the distribution of pressure loss along the coronary vessels. FFR derived from CT (FFRCT) provides a virtual pullback curve that may also aid in the assessment of the distribution of epicardial coronary resistance in the non-invasive setting. The present study aims to determine the accuracy of the virtual FFRCT pullback curve using a motorized invasive FFR pullback as reference in patients with stable coronary artery disease. Methods and results FFR values were extracted from coronary vessels at approximately 1 mm to generate pullback curves. Invasive motorized FFR pullbacks were acquired using a dedicated device at a speed of 1 mm/s. A total of 3172 matched FFRCT and FFR values were obtained in 24 vessels. The correlation coefficient between FFRCT and FFR was 0.76 (95%CI 0.75 to 0.78; p  Conclusion The evaluation of epicardial coronary resistance using coronary CT angiography with FFRCT was feasible. FFRCT virtual pullback appears to be accurate for the evaluation of pressure gradients. Lesions gradients were overestimated by FFRCT. FFRCT has the potential to identify the physiological pattern of coronary artery disease in the non-invasive setting.