SNIP1 and hypoplastic left heart syndrome: Other clinical features associated with SNIP1-related disorder include a variable spectrum of congenital cardiac defects (60% of individuals), including hypoplastic left heart syndrome, aortic stenosis and bicuspid aortic valve, aortic coarctation, aortic root dilatation, atrial septal defect (ASD), ventricular septal defect (VSD), patent ductus arteriosus (PDA), pulmonary artery stenosis and mitral valve regurgitation, 12% of affected individuals developed cardiomyopathy (left ventricular noncompaction).