Indications for surgical closure of a ventricular septal defect in childhood include congestive cardiac failure, pulmonary hypertension, severe aortic insufficiency and prior bacterial endocarditis. It is unlikely that a significant ventricular septal defect will be missed in childhood and therefore ventricular septal defects seen in adulthood tend to be small and isolated. In a small number of patients with Eisenmenger syndrome, i.e. ventricular septal defect with established pulmonary vascular disease, no intervention is possible.

The natural history of small congenital ventricular septal defects was thought to be favourable but longer follow up has demonstrated that 25% of adults with small ventricular septal defects may suffer from complications over longer periods of time. The complications documented were: infective endocarditis, aortic regurgitation, arrhythmias and myocardial dysfunction. Whilst closure of a ventricular septal defect protects against infective endocarditis, there are no data to suggest a protective effect against the development of late arrhythmias, sudden death or ventricular dysfunction.

The risk of bacterial endocarditis in patients with a ventricular septal defect is low (14.5 per 10,000 patient years). Prior or recurrent endocarditis on a ventricular septal defect would be deemed an indication for surgical closure even though the risks of endocarditis are low.

Whilst the majority of congenital ventricular septal defects are in the perimembranous or trabecular septum, a small percentage are found in the doubly committed subarterial position. This small sub group may be complicated by aortic valve cusp prolapse into the defect with development of subsequent aortic regurgitation which may be progressive and severe. The detection of aortic regurgitation in such a defect is considered an indication for surgical closure in most centres.

The mortality for surgical closure of a post-infarction ventricular septal defect may be up to 50%. Cardiogenic shock is exacerbated by the acute left ventricular volume load from the shunt through the ventricular septal defect. There is a small but growing experience of transcatheter device closure of such defects which avoids the need for cardiopulmonary bypass.

In summary, the indications for closure of a ventricular septal defect in an adult include the presence of a significant left to right shunt in the absence of pulmonary vascular disease, progressive aortic valve disease, recurrent endocarditis and acute postinfarction rupture in patients with haemodynamic compromise. Currently there is no evidence that closure of a small ventricular septal defect would prevent the occurrence of arrhythmias and ventricular dysfunction in the long term. The presence of established pulmonary vascular disease (Eisenmenger syndrome) is a contraindication to surgical intervention.

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