Atrial septal defect. (Redirected from Patent foramen ovale) Atrial septal defect (ASD) is a congenital heart defect in which blood flows between the atria (upper chambers) of the heart. Normally, the atria are separated by a dividing wall, the interatrial septum.
If you think your cat is sleeping a lot, youâre not off base. Cats tend to sleep in some form or another for anywhere from 16 to 20 hours a day.
In sleep, as in all things, cats are highly individual. Some cats sleep less than 16 hours a day and some sleep more; some spend as much as thirty or forty percent of their sleep time in a deep sleep cycle (this is particularly true of older cats).