The part of the autonomic nervous system originating in the brain stem and the lower part of the spinal cord that, in general, inhibits or opposes the physiological effects of the sympathetic nervous system, as in tending to stimulate digestive secretions, slow the heart, constrict the pupils, and dilate blood vessels.
Paroxysmal supraventricular tachycardia (PSVT) Alternative names PSVT; Supraventricular tachycardia Definition: Paroxysmal supraventricular tachycardia (PSVT) is a rapid heart rate, which occurs from time to time (paroxysmal). PSVT starts with events taking place above the ventricles.
Supraventricular tachycardia (SVT) is a cardiac arrhythmia arising from improper electrical activity of the heart. It is a type of tachycardia (rapid heart rhythm) originating at or above the atrioventricular node. It can be contrasted with the potentially more dangerous ventricular tachycardias ârapid rhythms that originate within the ventricular tissue.