ACE and endothelial dysfunction: Pekdemir et al. demonstrated, with intravascular ultrasonography, decreasing fractional flow reserve in the coronary arteries in patients with CSF due to diffuse atherosclerosis.4 Tanriverdi et al. reported that the ACE I/D polymorphism correlated with carotid intima–media thickness, which is a sign of subclinical atherosclerosis.11 These findings suggest that endothelial dysfunction and diffuse atherosclerosis may play a role in the pathogenesis of CSF.