inotrope
Pronunciation: in-OH-trohp
Medication that alters the force of cardiac muscle contraction, either increasing (positive) or decreasing (negative) contractility.
Full Definition
An inotrope is a pharmacological agent that modifies the contractile strength of the heart muscle. Positive inotropes, such as dobutamine, dopamine, and milrinone, increase myocardial contractility and are used in acute heart failure or cardiogenic shock to improve cardiac output. Negative inotropes, including beta-blockers and some calcium channel blockers, decrease contractility and are used to reduce myocardial oxygen demand in conditions like hypertrophic cardiomyopathy or angina. The mechanism typically involves modulation of intracellular calcium availability or cyclic adenosine monophosphate levels.
Usage
Usage note: Specify whether referring to positive or negative inotropic effect; commonly confused with 'ionotrope' (incorrect spelling).
In Context
- "The patient required high-dose inotrope support with dobutamine and norepinephrine for cardiogenic shock." — ICU progress note
- "Negative inotrope therapy with metoprolol improved symptoms in this patient with obstructive cardiomyopathy." — Cardiology consultation