Midterm2

Chronotropic drugs may change the heart rate and rhythm by affecting the electrical conduction system of the heart and the nerves that influence it, such as by changing the rhythm produced by the sinoatrial node. 

• Positive chronotropes increase heart rate; negative chronotropes decrease heart rate.
• A dromotrope affects atrioventricular node (AV node) conduction. 
• A positive dromotrope increases AV nodal conduction, and a negative dromotrope decreases AV nodal conduction. 
• A lusitrope is an agent that affects diastolic relaxation.

Many positive inotropes affect preload and afterload.