the relationship between arrhythmia density observed during ambulatory monitoring , left ventricular ejection fraction ( ef ) , and response to antiarrhythmic drug therapy was evaluated in 94 patients presenting with ventricular fibrillation ( vf ) ( n = 20 ) or ventricular tachycardia ( vt ) ( n = 74 ) .
C0003811
arrhythmia
C0042510
ventricular fibrillation