Sinus tachycardia

Sinus tachycardia (also colloquially known as sinus tach or sinus tachy) is a physiological mechanism occurring appropriately in response to sympathetic activation and/or parasympathetic withdrawal, such as during exercise, anxiety, pain, hypovolemia, orthostatic hypotension, fever, infections, heart failure, pericarditis, diabetes-related autonomic dysfunction, drug abuse, catecholamine infusions, anticholinergic drugs, tobacco, caffeine, alcohol and beta-blocking agent withdrawal.

It is a sinus rhythm with an elevated rate of impulses, defined as a rate greater more than 100 beats/min (bpm) in an average adult. The normal resting heart rate in the average adult ranges from 60–100 bpm.

Inappropriate sinus tachycardia is a form of focal atrial tachycardia originating along the superior aspect of the crista terminalis in the “sinus node region” at rates above physiologic range, without relation to metabolic or physiologic demands. Sinus tachycardia is inappropriate when there is no known cause for the sinus tachycardia, Inappropriate sinus tachycardia occurs usually in young females in their 30s.
Sinus tachycardia

What is arrhythmia?

Arrhythmias are defined as any cardiac rhythm other than the normal sinus rhythm.  It is a disturbance of the normal heart rhythm. Cardiac arrhythmias were first noted in antiquity, when physicians began to palpate the arterial pulse.

Hippocrates noted that a slow pulse in elderly men heralded sudden death, and Galen predicted the impending death of an apparently healthy physician who had observed that his pulse was irregular. From an electrocardiographic point of view, arrhythmias may be divided into two different types
*Active arrhythmias
*Passive arrhythmias

Normal resting heart rate is 60 to 100 beats/min. A heartbeat that is too low or too fast can interfere with normal heart function and produce symptoms that can be minor or life threatening.

The incidence of the majority of arrhythmias increases with age progressively and arrhythmias are not frequent in children.

Patent may be asymptomatic or may experience the following:
*Fatigue, weakness
*Dizziness
*Light-headedness
*Fainting or near fainting
*Shortness or breadth.
What is arrhythmia?