voltage mapping
An electrophysiologic technique that measures local electrogram amplitude to identify areas of myocardial scar and healthy tissue.
Full Definition
Voltage mapping is an electrophysiologic technique that systematically measures the amplitude of local bipolar electrograms throughout the cardiac chamber to create a three-dimensional map distinguishing healthy myocardium from scar tissue. Normal myocardium typically generates electrograms with amplitudes >1.5 mV, while dense scar shows very low voltage (<0.5 mV). Intermediate voltages (0.5-1.5 mV) represent border zones that may harbor slow conduction channels critical for reentrant arrhythmias. Voltage mapping guides ablation strategies in patients with structural heart disease, helping identify substrate for ventricular tachycardia and areas suitable for ablation while avoiding damage to healthy tissue.
Usage
Usage note: Essential for substrate-based ablation approaches; voltage thresholds may vary by mapping system.
In Context
- "Voltage mapping revealed an extensive low-voltage area in the inferior left ventricle consistent with prior myocardial infarction." — Electrophysiology study findings
- "The border zone identified by voltage mapping between normal and scarred myocardium was targeted for substrate ablation." — Ablation procedure plan