pace mapping
An electrophysiologic technique that compares the QRS morphology during pacing with that during clinical ventricular tachycardia to localize arrhythmia origin.
Full Definition
Pace mapping is an electrophysiologic technique used to localize the origin of ventricular tachycardia by comparing QRS morphologies. During the procedure, pacing is performed from multiple ventricular sites at a cycle length similar to the clinical ventricular tachycardia. The QRS morphology during pacing is compared to that recorded during the clinical arrhythmia across all 12 ECG leads. A perfect pace map (12/12 lead match) suggests that the pacing site is very close to the ventricular tachycardia exit site. This technique is particularly valuable when the clinical arrhythmia is not inducible or not hemodynamically tolerated during the electrophysiology study.
Usage
Usage note: Complementary to activation mapping; particularly useful when VT is not inducible or sustained.
In Context
- "Pace mapping from the right ventricular outflow tract showed a 12/12 lead match with the clinical ventricular tachycardia morphology." — Mapping procedure report
- "The inferior lead QRS morphology during pace mapping helped distinguish between right and left ventricular outflow tract origins." — Differential diagnosis assessment