AMRINONE

Action

• Phosphodiesterase inhibitor: resulting in increased cAMP and therefore an increase in the calcium influx like that caused by beta- agonists resulting in increased inotropic effect

• Inotropic effect is synergistic with beta-agonists

• Inotropic effect may not be associated with increase myocardial oxygen consumption

• Also has a peripheral vasodilatory effect due to increased cAMP reducing afterload

Indication

• Heart failure; severe left ventricular dysfunction

• Advantage can be taken of the inotropic action without its vasodilatory activity by combining it with a alpha-adrenergic vasoconstrictor

Contraindication

• Thrombocytopaenia

Adverse effects

• Vasodilation

Dose

• 0.5 — 1.5/mg/kg iv bolus (slowly)

5 — 30 mcg/kg/min infusion