Paroxysmal, or sporadic, supraventricular tachycardia usually occurs without other symptoms. However, it may be associated with a number of medical conditions, such as the following:
Hardening of the arteries (atherosclerosis)
Heart failure
Thyroid disease
Chronic lung disease
Pneumonia
Pulmonary emboli, or blood clots migrating into the lung arteries from elsewhere in the body
Pericarditis
Certain drugs and social habits
Cocaine abuse
Alcohol abuse
Smoking
Drinking too much caffeine in coffee, tea, or soft drinks
Emotional stress
Structural abnormalities, such as Wolff Parkinson White syndrome, in which extra electrical tissue sets up abnormal electrical circuits
Supraventricular tachycardia may also be a side effect of medications such as digitalis, asthma medications, or cold remedies.
In some cases, the cause of supraventricular tachycardia is unknown.
Circulatory System
Circulatory System, or cardiovascular system, in humans, the combined function of the heart, blood, and blood vessels to transport oxygen and nutrients to organs and tissues throughout the body and carry away waste products. Among its vital functions, the circulatory system increases the flow of blood to meet increased energy demands during exercise and regulates body temperature.