Bouts of rapid, regular heart beating that originate in the upper chamber of the heart (atrium). Abbreviated PAT. PAT is caused by abnormalities in the atrioventricular (AV) node that lead to rapid firing of electrical impulses from the atrium that bypass the AV node under certain conditions, including excess alcohol consumption, stress, caffeine use, overactive thyroid or excessive thyroid hormone intake, and use of certain drugs. PAT is an example of an arrhythmia in which the abnormality is in the electrical system of the heart, while the heart muscle and valves may be normal. Also known as paroxysmal supraventricular tachycardia.
- Paroxysmal sleep
A neurological disorder marked by a sudden recurrent uncontrollable compulsion to sleep. Also known as narcolepsy. The disorder is often associated with cataplexy (a sudden loss of muscle tone and paralysis of voluntary muscles associated with a strong emotion), sleep paralysis (immobility of the body that occurs in the transition from sleep to wakefulness), what […]
- Parrot fever (psittacosis)
An infectious disease due to a bacteria (Chlamydia psittaci) contracted from psittacine birds, especially caged birds like parrots, parakeets, and lovebirds and also in turkey processing plants. The bacteria enter the human body by inhalation of air that contains it or by a bite from an infected bird. The incubation period is 1 to 3 […]
- Parry's disease
Toxic multinodular goiter. Named for the English physician Caleb Hillier Parry (1755-1822). also called Plummer’s disease.
Development of a germ cell without fertilization. A form of nonsexual ‘reproduction.
- Partial hysterectomy
Surgical removal of the uterus but not the cervix. Also known as subtotal hysterectomy.