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.
ADVERTISEMENT. Cats sleep an average of fifteen hours a day, and some can sleep up to twenty hours in a twenty-four hour period.Which raises the question: Why do cats sleep so much?DVERTISEMENT. Cats sleep an average of fifteen hours a day, and some can sleep up to twenty hours in a twenty-four hour period. Which raises the question: Why do cats sleep so much?