Pattern of Congenital Heart Defects in 22q11 Microdeletion Syndrome in India – A Tertiary Care Cardiac Hospital Based Study

The 22q11.2 microdeletion syndrome is one of the common microdeletion syndromes seen among children with Congenital Heart Defects. Population based studies have shown the prevalence of 22q11.2 microdeletion syndrome range from 1 in 4000 to 1 in 6000 live births.1,2 Over 80% of children with 22q11.2 microdeletion syndrome have Congenital Heart Defects.1,3,4 Diagnosis of 22q11.2 microdeletion syndrome among children with Congenital Heart Defects has an implication on medical & surgical management of Congenital Heart Defects. Since more than 30% of these children have associated major extracardiac anomalies (other than velopalatal anomalies) which may present late in life, it becomes important to look for them and follow them up.1 Thus, 22q11.2 microdeletion syndrome has major implications not only on the health of the affected child but also on the quality of life of other members in the family. The 22q11.2 microdeletion syndrome is characterized by variable clinical features consisting of Congenital Heart Defects, aplasia or hypoplasia of the thymus and/or parathyroid glands, immune functional abnormalities, palatal abnormalities, speech delay, learning difficulties, intellectual disability, facial dysmorphism, hypothyroidism, genitourinary malformations and so on.1,3,4 Main diagnostic clues to 22q11.2 microdeletion syndrome could be typical Congenital Heart Defects (conotruncal anomalies or aortic arch anomalies), characteristic phenotypic features and other extracardiac manifestations like hypocalcemia.3,4,5 However clinical features of 22q11.2 microdeletion syndrome are highly variable. Few children might have variable or subtle phenotypic features and might not have typical Congenital Heart Defects.