The only normal rhythm of the heart, is a normal sinus rhythm. Usually from 60 to 100 beats per minutes.
Any deviation from normal rate, is considered abnormal and is called Arrhythmia..
The most common way to categorize arrythmias are: bradyarrhythmia and tachyarrhythmia.
Bradyarrhythmia are slow heart rate, fewer than 60 beats per minute,
and tachyarrhythmia are fast heart beat. with a heart rate higher than 100 beat per minute.
Tachyarrhythmia and tachycardia are synonyms.
While it is common to have tachycardia as a physiological response to exercise or stress, it causes concern when it occurs at rest. Babies and kids have naturally fast heart rate.
In many cases, Tachycardia has no symptoms, but if left untreated it can have long term complications. Sometimes it can be fatal.
There are many different types of tachycardia.
Sinus tachycardia is The most Common form of untreated tachycardia, refers to a typical increase in the heart rate often caused by exercise or stress. Such tachycardias commonly aren’t treated because most of them are temporary and physiological.
Atrial fibrillation – is the most common Treated arrythmia. Chaotic, irregular electrical signals in the upper chambers of the heart, which is called atria. causes a fast heartbeat.
Some people who have atrial fibrillation, don’t know they have it and don’t have any symptoms. Others may experience one or more of the following symptoms:
Irregular heartbeat. Heart palpitations feelings of having a fast-beating, fluttering or pounding heart.
Lightheadedness, Extreme fatigue, Shortness of breath, Chest pain
Risk factors for Atrial fibrillation include:
Advancing age, High blood pressure, Obesity, Diabetes. Heart failure and Ischemic heart disease.
The main goals of treatment are to prevent circulatory instability and stroke. Rate or rhythm control is used to achieve the former, whereas anticoagulation is used to decrease the risk of the latter. If cardiovascular unstable due to uncontrolled tachycardia, immediate cardioversion is indicated.
Ventricular Tachycardia
Ventricular tachycardia is a fast heart rate that starts in the heart’s lower chambers (ventricles). This type of arrhythmia may be life-threatening, requiring immediate diagnosis and treatment.
Symptoms include:
Symptoms for ventricular tachycardia vary. Common symptoms include:

Dizziness, Palpitations, Shortness of breath, Nausea, Lightheadedness, Falling unconscious,
Cardiac arrest in extreme cases.
Ventricular tachycardia is most often associated with disorders that interfere with the heart’s electrical conduction system. These disorders can include:
Lack of coronary artery blood flow, depriving oxygen to heart tissue
Cardiomyopathy distorting the heart’s structure
Medication side effects
Illicit drugs such as cocaine
Sarcoidosis (an inflammatory disease affecting skin or body tissues)

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