Pharmacotherapeutics of Positive Inotropes | AORN Journal | Find ...
An inotrope is an agent that affects myocardial contractility. A positive inotrope causes increased contractility (eg, dobutamine), and a negative inotrope causes decreased contractility (eg, the beta-blocker metoprolol). A chronotrope is an agent that affects heart rate. Positive chronotropes cause an increase in heart rate (eg, epinephrine, isuprel). Negative chronotropes cause a decrease in the heart rate. Examples of negative chronotropes are beta-blockers and rate control calcium channel blockers (eg, diltiazem). A dromotrope affects atrial-ventricular (AV) node conduction. A positive dromotrope increases AV nodal conduction (eg, atropine sulfate), and a negative dromotrope slows AV nodal conduction (eg, lanoxin). A lusitrope is an agent that affects diastolic relaxation.