Santoro G et al. (2005) Similar cardiac remodelling after transcatheter atrial septal defect closure in children and young adults. Heart [doi:10.1136/hrt.2005.070169]

Atrial septal defect (ASD) can cause chronic right chamber volume overload, leading to arrhythmias and impaired left ventricular function. ASD closure has been shown to be less effective after long-term volume overload, leading to the belief that early intervention is best, even in asymptomatic patients. The procedure is associated with risks, however, especially in the very young. Santoro et al. suggest that up to early adulthood, age does not affect the extent of cardiac remodeling following percutaneous ASD closure, and that the benefits of delayed closure could outweigh any potential risks.

In this nonrandomized study, 46 asymptomatic patients with ASD diameter >20 mm, an invasively measured pulmonary to systemic circulation flow ratio (Qp:Qs) of >1.5:1, or both, underwent transcatheter closure between March 2000 and March 2004 (25 aged <16 years [median 8 years], and 21 aged >16 years [median 38 years]). In both age-groups, right chamber size reduced to normal size within just a few weeks. At 6 months there were no significant differences between the two age-groups in either time course or extent of cardiac remodeling. Both groups displayed increases in left ventricular transverse diameter (P <0.05) and reductions in right atrial volume, right ventricular transverse diameter and right ventricular : left ventricular diameter ratio (P <0.001 for all). Left atrial volume and left ventricular ejection fraction did not change significantly in either group.

The authors conclude that positive cardiac remodeling begins very soon after percutaneous closure of large ASD, and is unaffected by the magnitude and duration of volume overload. Additional, longer-term studies are needed, with larger patient populations and more-specific endpoints.