Arsenic trioxide = (As)2(O)3
Physiologic effects of arsenic trioxide:
(1) prolongation of the QTc interval
(2) prolongation of the action potential
Arrhythmias that may occur:
(1) torsades de pointes
(2) non-sustained ventricular tachycardia
(3) ventricular premature contractions
(4) nonsustained supraventricular tachycardia
(5) sinus tachycardia
Risk factors for arrhythmias:
(1) high dose of the arsenic trioxide
(2) concurrent therapy with other drugs prolonging the QTc interval
(3) conditions associated with delayed cardiac repolarization (bradycardia, hypomagnesemia, hypokalemia)
