Ventricular septal defects are the most common congential cardiac malformations, and often occur as part of more complex abnormalities, such as tetralogy of Fallot or transposition.
Prenatal diagnosis should be straightforward using a long axis view of the ventricles, followed by a short axis sweep from apex to base.
Many isolated small VSDs, especially of the muscular type, will close spontanteously in utero, or in infancy.
Significant VSDs that contribute to failure to thrive, or those associated with increased pulmonary vascular flow, should be surgically repaired by 6 months of age.
Recent advances in minimally invasive transcatheter septal occlusion devices hold great promise as an alternative to open surgical repair with cardiopulmonary bypass.
Ventricular septal defect (VSD) refers to a congenital malformation in the development of the interventricular septum. VSDs can occur in the muscular or membranous portions of the septum. Muscular VSDs may be further subdivided into inlet, trabecular, or infundibular defects (Soto et al., 1980; Minette and Sahn, 2006). VSDs may also be classified as being either subvalvular or muscular (Capelli et al., 1983). Subvalvular VSDs are directly related to the atrioventricular or semilunar valves, without interposed muscle between the defect and the valve cusps. Such subvalvular defects may be further subclassified as inlet, subtricuspid, subaortic, subpulmonary, or double-committed subarterial, in which the defect is below the pulmonary and aortic valves. Muscular VSDs are bordered on all sides by muscle and are not directly related to the valves. Such defects may be further subclassified as being apical, central, or outlet in location. Most of these VSD types can be defined by echocardiography, although it is important to realize that small muscular defects can be missed by sonography during both the prenatal and the postnatal periods (Capelli et al., 1983).
VSDs usually cause no hemodynamic effects in utero because of the similarity in pressures between the right and left sides of the heart during prenatal life. Most VSDs are also asymptomatic immediately following birth. If the VSD persists after birth, it may allow for the development of a left to-right shunt, which can result in congestive heart failure or pulmonary hypertension.
VSDs are the most common single congenital cardiac malformation, accounting for 26% of all structural cardiac abnormalities (Ferencz et al., 1987). In an earlier population series, the incidence of VSD was 2 in 10,000 total births (Mitchell et al., 1971). However, with the increasing use of prenatal and neonatal echocardiography, the birth incidence of VSDs seems to be much higher than previously suggested (Minette and Sahn, 2006). In one series, 5% of all newborns were found to have an isolated muscular VSD (Roguin et al., 1995). The most accurate estimate of birth prevalence of VSD is 3.5 per 1000 livebirths ...