dromotrop

Dromotropism refers to the effect of a substance on the velocity of conduction of an impulse through tissue, particularly cardiac tissue. It is often discussed in the context of pharmacology and electrophysiology, specifically concerning the heart's electrical activity. Positive dromotropism indicates an increase in the speed of conduction, while negative dromotropism signifies a decrease. This property is distinct from chronotropism, which relates to heart rate, and inotropism, which relates to contractility.

The sinoatrial (SA) node and the atrioventricular (AV) node are key areas where dromotropic effects are observed. The AV node, in particular, plays a crucial role in regulating the transmission of electrical signals from the atria to the ventricles. Medications that affect dromotropism can therefore influence the timing and coordination of heartbeats. For instance, drugs that block certain ion channels or neurotransmitter receptors can alter the speed at which electrical impulses travel through the AV node. Understanding dromotropic effects is important for the diagnosis and treatment of various cardiac arrhythmias and conduction disorders.