Improved treatment options in paediatric cardiology and congenital heart surgery have resulted in an ageing population of patients with cyanotic congenital heart disease (CCHD). The risk of acquired heart disease such as atherosclerosis increases with age.Previous studies have speculated whether patients with CCHD are protected against atherosclerosis. Results have shown that the coronary arteries of patients with CCHD are free from plaques and stenosis. Decreased carotid intima-media thickness and low total plasma cholesterol may indicate a reduced risk of later development of atherosclerosis. However, the evidence is still sparse and questionable, and a reasonable explanation for the decreased risk of developing atherosclerosis in patients with CCHD is still missing.This review provides an overview of what is known about the prevalence and potential causes of the reduced risk of atherosclerosis in patients with CCHD.