Tachycardia overview
|
Tachycardia Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Tachycardia overview On the Web |
|
American Roentgen Ray Society Images of Tachycardia overview |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-In-Chief: M.Umer Tariq [2]
Overview
Tachycardia is a form of cardiac arrhythmia which refers to a rapid beating of the heart. By convention the term refers to heart rates greater than 100 beats per minute in the adult patient. Tachycardia may be a perfectly normal physiological response to stress. However, depending on the mechanism of the tachycardia and the health status of the patient, tachycardia may be harmful, and require medical treatment. In extreme cases, tachycardia can be life threatening.
Tachycardia can be harmful in three ways. Firstly, if the heart is pumping too fast for an extended period of time it will change the balance of oxygen and carbon dioxide in the hemoglobin in the blood; this is normal during exercise but when resting this is quite dangerous. Second, when the heart beats too rapidly, it may pump blood less efficiently. Thirdly, the faster the heart beats, the more oxygen and nutrients the heart requires. This may leave patients feeling out of breath or cause angina. This can be especially problematic for patients suffering from ischemic heart disease.
Diagnosis
Electrocardiogram
Tachycardia is defined as heart rate more than 100 beats per minute and it can be sinus tachycardia, ventricular tachycardia or supraventricular tachycardia. Ventricular tachycardia can be distinguished by broad QRS complexes on an ECG.