PURPOSE: Invasively measured fractional flow reserve (FFR) is associated with outcome in heart transplant (HTx) patients. Non-invasive coronary computed tomography angiography (CCTA)-derived FFR (FFRct) provides additional functional information from anatomical CT images. The anatomical model of the coronary arteries derived from CCTA is used to calculate the FFRct values at each point in the coronary arteries. We describe the first use of FFRct in a cohort of HTx patients. METHODS: HTx patients underwent CCTA with FFRct as part routine follow-up to screen for cardiac allograft vasculopathy (CAV). FFRct was performed off-site by a company. FFRct was measured distal to each coronary stenosis >30% and at the most distal location of each of the 3 major coronary arteries (right, left anterior descending and circumflex coronary artery). Overal distal FFRct was calculated as the mean of 3 vessels per patient. During 90-day follow-up, performance of additional tests for coronary assessment and revascularization were recorded. RESULTS: 73 patients (age 56 (42-65) years, 63% males) at 11 (8-16) years after HTx were included. In the 54 patients without a hemodynamically significant focal FFRct stenosis (FFRct >0.80), the distal left anterior descending artery FFRct was <0.90 in 72% of patients and 9 (17%) patients had ≥1 coronary artery with a distal FFRct ≤0.8, including 1 patient with a distal FFRct ≤0.8 in all coronary vessels. Overall distal FFRct values were 0.88 (0.86-0.91) (median, 25 - 75 percentile), 0.87 (0.86-0.90), and 0.89 (0.86-0.91) at 5-9, 10-14 or ≥15 years after transplantation, respectively (p=0.89). Additional tests were performed in 12 (16%) patients, which resulted in revascularization in 7 (10%) patients. CONCLUSION: FFRct was successfully performed on CCTA scans of HTx patients and demonstrated that more than a quarter of patients had a focal coronary stenosis with FFRct ≤0.8. Even in the absence of a focal stenosis FFRct values are often abnormal in HTx patients.

doi.org/10.1016/j.healun.2020.01.1259, hdl.handle.net/1765/127514
The Journal of Heart and Lung Transplantation
Department of Radiology

Budde, R.P.J, Nous, F.M.A, Roest, S, Constantinescu, A.A, Nieman, K, Brugts, J.J, … Manintveld, O.C. (2020). Non-Invasive Functional Coronary Artery Evaluation by CT-Derived Fractional Flow Reserve (FFRct) in Heart Transplant Patients. The Journal of Heart and Lung Transplantation, 39(4). doi:10.1016/j.healun.2020.01.1259