Incidence
On the basis of the New England Regional Infant Cardiac Program, those with isomeric atrial appendages can be inferred to account for just under one-twentieth of all infants with congenital cardiac malformations.26 The reported incidence in necropsy studies is around 3%, but no more than 1.5% in echocardiographic investigations.7,9-13,27 Isomerism is said to occur in approximately one out of every 5000-7000 live births with patients of Asian descent.9-13,27 Right isomerism is more frequently reported in necropsy studies compared to surgical series, reflecting the complexity of the cardiac anomalies, poor natural outcome, inoperability, and increased risk of sepsis.7,9-13,27