Severe Mitral Valve Regurgitation due to Significant Coronary Artery Stenosis in a 14-month-old boy with Williams-Beuren Syndrome

Williams-Beuren syndrome (WBS) is characterized by a combination of cardiovascular malformations, typical dysmorphic stigmata, a moderate developmental delay and behavioral abnormalities. According to the literature the incidence is within a range from 1:20 000 to 1:7 500 (Yildiz O et al., World J Pediatr Congenit Heart Surg 2015; 6: 311–316). Microdeletion of chromosome region 7q11.23 is pathognomonic, affecting the elastin gene (von Beust G et al., Klin Padiatr 2000; 212: 299–307). Due to reduced elastin content elasticity in the media of the arterial vessel wall is reduced, resulting in a vasculopathy affecting preferentially the medium size and large arteries. As a characteristic feature supravalvular aortic and pulmonary artery stenosis is very common in patients with WBS. The supravalvular aortic stenosis may also affect the origin of the coronary arteries resulting in an increased risk of myocardial ischemia (Collins RT 2nd, Circulation 2013; 127: 2125–2134). We report the case of a little boy with ischemic mitral regurgitation due to stenosis of the left main coronary artery.