The term ''dromotropic'' derives from the Greek word δρόμος ''drómos'', meaning "running", a course, a race. A dromotropic agent is one which affects the conduction speed (in fact the magnitude of delay) in the
AV node, and subsequently the rate of electrical impulses in the heart.
Positive dromotropy increases
conduction velocity (e.g.
epinephrine stimulation), negative dromotropy decreases velocity (e.g.
vagal stimulation).
Non-dihydropyridine
calcium channel blockers such as
verapamil block the slow inward calcium current in cardiac tissues, thereby having a negatively dromotropic, chronotropic and inotropic effect. This (and other) pharmacological effect makes these drugs useful in the treatment of
angina pectoris. Conversely, they can lead to symptomatic disturbances in cardiac conduction and
bradyarrhythmias, and may aggravate
left ventricular failure.
See also
*
Bathmotropic
*
Inotrope
*
Catecholamines
References
{{Cardiovascular physiology
Cardiovascular physiology