Definition:

Ventricular septal defect (VSD) is the most common type of cardiovascular developmental anomaly and is an important risk factor for the substantially increased morbidity and mortality in newborns. Congenital heart disease (CHD) is divided into more than 30 subtypes based on the cardiac or vascular abnormalities, of which VSD, atrial septal defect (ASD) [DS:H00546], tetralogy of Fallot (TOF) [DS:H00549], and Holt-Oram syndrome (HOS) [DS:H00433] are clinically the most common. VSDs can exist in isolation, can be complicated by additional intracardiac lesions, or can be part of more complex combinations, such as TOF, double outlet right ventricle [DS:H00918], or functionally univentricular hearts [DS:H01787]. Congenital VSDs arise from perturbations of cardiac development during embryogenesis and both environmental and genetic risk factors have been implicated in VSDs. Growing evidence highlights the key role of several transcription factors, including GATA4, in septogenesis.