Concealed Entrainment
A pacing technique where overdrive pacing from within a reentrant circuit produces concealed fusion, confirming circuit participation.
Full Definition
Concealed entrainment is an electrophysiologic phenomenon observed when pacing from within a protected corridor of a reentrant circuit. The paced impulses travel orthodromically through the circuit while simultaneously conducting antidromically to collide with the returning wavefront, creating concealed fusion. Surface ECG morphology remains unchanged during pacing, but the return cycle equals the pacing cycle length. This technique is crucial for identifying critical components of reentrant circuits and distinguishing true circuit participation from bystander regions. Concealed entrainment mapping is fundamental to modern ablation strategies for complex arrhythmias.
Usage
Usage note: Use as a compound term; avoid separating 'concealed' and 'entrainment' with other words.
In Context
- "Concealed entrainment confirmed this site as part of the critical VT isthmus." — EP study report
- "The finding of concealed entrainment validated the substrate mapping approach." — Research publication