Ventricular tachycardia

An abnormally rapid heart rhythm that originates from a ventricle, one of the lower chambers of the heart. Although the beat is regular, ventricular tachycardia is life-threatening because it can lead to a dreaded condition, ventricular fibrillation. In ventricular fibrillation, the ventricles beat rapidly in a chaotic, purposeless fashion. The heart cannot pump blood effectively to the body. If untreated, ventricular fibrillation can be fatal within minutes, or even seconds. An estimated 250,000 Americans die in this way each year. Ventricular tachycardia is most commonly associated with heart attacks or scarring of the heart muscle from a previous heart attack.

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ventricular tachycardia n tachycardia that is associated with the generation of electrical impulses within the ventricles and is characterized by an electrocardiogram having a broad QRS complex abbr. VT,{{}}V-tach

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a dangerously fast beating of the heart stemming from an abnormal focus of electrical activity in the ventricle. The electricity does not pass through the heart along the usual channels and as a result the contraction of the heart muscle is often not as efficient as normal, which can result in a sudden drop in blood pressure or even cardiac arrest. Left untreated it will prove ultimately fatal. See also arrhythmia.

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(VT) an abnormally rapid ventricular rhythm with aberrant ventricular excitation (wide QRS complexes), usually in excess of 150 per minute, which is generated within the ventricle and is most commonly associated with atrioventricular dissociation. Minor irregularities of rate may also occur. Evidence implicates a reentrant pathway as the usual cause.