RESUMEN
OBJECTIVES: To evaluate computed tomography fractional flow reserve (FFRCT) values in distal parts of the coronaries in an asymptomatic cohort of marathon runners without any coronary stenosis for potentially false-positive values. METHODS: Ninety-eight asymptomatic male marathon runners (age 53 ± 7 years) were enrolled in a prospective monocentric study and underwent coronary computed tomography angiography (CCTA). CCTA data were analyzed for visual coronary artery stenosis. FFRCT was evaluated in 59 participants without coronary artery stenosis in proximal, mid, and distal coronary sections using an on-site software prototype. RESULTS: In participants without coronary artery stenosis, abnormal FFRCT values ≤ 0.8 in distal segments were found in 22 participants (37%); in 19 participants in the LAD; in 5 participants in the LCX; and in 4 participants in the RCA. Vessel diameters in participants with FFRCT values > 0.80 compared to ≤ 0.80 were 1.6 ± 0.3 mm versus 1.5 ± 0.3 mm for distal LAD (p = 0.025), 1.8 ± 0.3 mm versus 1.6 ± 0.5 mm for distal LCX (p = 0.183), and 2.0 ± 0.4 mm versus 1.5 ± 0.2 mm for distal RCA (p < 0.001). CONCLUSIONS: Abnormal FFRCT values of ≤ 0.8 frequently occurred in distal coronary segments in subjects without any anatomical coronary artery stenosis. This effect is only to some degree explainable by small distal vessel diameters. Therefore, the validity of hemodynamic relevance evaluation using FFRCT in distal coronary artery segment stenosis is reduced. KEY POINTS: ⢠Abnormal FFRCT values (≤ 0.8) occurred in over a third of the subjects in the distal LAD despite the absence of coronary artery stenosis.. ⢠Therefore, the validity of hemodynamic relevance evaluation in distal coronary artery segment stenosis is reduced. ⢠Decision-making based on abnormal FFRCT values in distal vessel sections should be performed with caution and only in combination with visual assessment of the grade of stenosis..