decremental conduction
A conduction property where increasing stimulation frequency results in progressively slower conduction velocity and longer refractory periods.
Full Definition
Decremental conduction is an intrinsic property of certain cardiac tissues, most notably the AV node, where increasing the frequency of stimulation results in progressively slower conduction velocity and longer effective refractory periods. This rate-dependent behavior serves as a protective mechanism, preventing excessively rapid ventricular rates during atrial tachyarrhythmias. The phenomenon is also observed in accessory pathways and areas of diseased myocardium. Understanding decremental conduction is essential for interpreting AV conduction patterns during atrial fibrillation and for distinguishing different types of supraventricular tachycardia during electrophysiologic testing.
Usage
Usage note: Distinguish from Wenckebach periodicity, which is a specific pattern of decremental conduction.
In Context
- "The accessory pathway demonstrated decremental conduction properties during rapid atrial pacing." — Electrophysiology study report
- "Decremental conduction through the AV node explained the irregular ventricular response during atrial fibrillation." — ECG interpretation