Pulseless Ventricular Tachycardia
Abstract
Pulseless ventricular tachycardia is a life-threatening cardiac arrhythmia in which coordinated ventricular contractions are replaced by very rapid but ineffective contractions, leading to insufficient organ perfusion and heart failure. Pulseless ventricular tachycardia is a medical emergency.
Due to rapid ventricular contractions, the ventricular filling decreases markedly, leading to a dramatic decrease in cardiac output. As a result, a pulse is absent. Electrophysiology identifying factors for pulseless ventricular tachycardia include; tachycardia (>100 bpm), wide QRS complexes (> 120 milliseconds), atrioventricular (AV) dissociation, presence of fusion or capture beats and an electrical axis between -90 to -180. There are several scoring systems to differentiate ventricular tachycardia from a wide complex supraventricular tachycardia, but 90% of wide complex tachycardia cases will be ventricular tachycardia.
The ventricular arrhythmia can be characterized as either monomorphic (no variation of the QRS from beat to beat) or polymorphic (changing or multiform QRS from beat to beat). The most common cause of pulseless ventricular tachycardia is cardiac ischemia.