Editing Tetralogy of Fallot (section)

=== Atrial septal defects ===
Atrial septal defects (ASDs) are a kind of congenital heart abnormality in which a tiny opening exists between the two atria of the heart.<ref name="Thorne_2011">{{Cite journal|date=October 2011| veditors = Thorne S, Clift P |title=Atrial septal defects (ASDs) |journal=Oxford Medicine Online| pages = 93–104 |doi=10.1093/med/9780199228188.003.0013|isbn=978-0-19-172592-0}}</ref><ref name="NORD" /> The burden on the right side of the heart is increased as a result of these abnormalities, as is the blood flow to the lungs.<ref name="Thorne_2011" /><ref name="NORD" /> This leads to excessive blood flow to the lungs and an increased workload on the right side of the heart.<ref name="Thorne_2011" /><ref name="NORD" /> Another common finding associated with ASDs is right ventricular hypertrophy, also known as enlargement of the right ventricle.<ref name="NORD" />