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.
1. Cats can sleep as much as 16 hours a day, and older cats spend even more time at rest â as much as 20 hours a day. That sleeping habit is a result of the catâs evolution, nutritional habits, and physiology.hey do, however, sleep deeply and even dream. The remaining quarter of catsâ sleeping hours is spent in deep sleep, but older cats might spend as much as 30 percent or 40 percent of the time at that level. Cats in deep sleep are usually curled up with their eyes tightly closed.