Inotropic agent

Definition

An inotropic agent is a substance that alters the force or energy of cardiac muscle contractions. These agents are commonly used to manage heart failure and other cardiac emergencies.

5 Must Know Facts For Your Next Test

1. Positive inotropic agents increase the strength of heart muscle contractions, improving cardiac output.
2. Negative inotropic agents decrease the strength of heart muscle contractions and are less commonly used in emergency settings.
3. Common positive inotropic agents include digoxin, dopamine, and dobutamine.
4. Inotropic agents can affect both preload (volume of blood entering the heart) and afterload (resistance the heart must pump against).
5. Side effects of inotropic agents may include arrhythmias, hypertension, and increased myocardial oxygen demand.

Review Questions

• What is the primary purpose of positive inotropic agents?
• Name three common positive inotropic agents used in cardiac emergencies.
• What are potential side effects associated with the use of inotropic agents?

Related terms

Chronotropic agent: A substance that affects the heart rate.

Dromotropic agent: A substance that affects the conduction speed of electrical impulses through the heart.

Cardiac output: The volume of blood pumped by the heart per minute.