Inotropes
Understand the detailed pharmacology of inotropes
and vasopressors
Inotropes are agents which alter myocardial contractility.
- Positive inotropes increase contractility
- Negative inotropes decrease contractility
Classes of Positive Inotrope
Classes | Class I: Increase Intracellular Calcium | Class II: Calcium Sensitisers | Class III: Metabolic/Endocrine |
---|---|---|---|
Examples | Adrenaline, milrinone, glucagon, digoxin | Levosimendan | T3, Insulin |
General Mechanism of Action | Increase intracellular Ca2+ by a variety of different pathways | Increase sensitivity of actomyosin to Ca2+ | Variable. T3 potentiates the effect (or increases expression of) cardiac β1 receptors |
References
- Leslie RA, Johnson EK, Goodwin APL. Dr Podcast Scripts for the Primary FRCA. Cambridge University Press. 2011.
- Tielens ET, Forder JR, Chatham JC, Marrelli SP, Ladenson PW. Acute L-triiodothyronine administration potentiates inotropic responses to P-adrenergic stimulation in the isolated perfused rat heart. Cardiovascular Research 32 (1996) 306-310.