Spatial resolution of catheter-based ventricular pace activation mapping by cross-correlation of signal-averaged electrograms

Prior work suggests resolution of ventricular pace mapping by ECG is 20 mm. Experimental pacing was performed in a swine model and computer-based signal processing algorithms were used to enhance 2-point spatial resolution of ventricular endocardial pace activation mapping. Unipolar sites in swine right ventricle (RV) and left ventricle (LV) were paced using multipolar catheters of known spacing. Up to 25 LV endocardial signals were recorded with a basket catheter. Catheter stability was assessed by fluoroscopy. A difference metric was calculated from changes in electrogram morphology and time shifts in signals generated from two different pacing sites. Receiver operating characteristics were calculated using this difference metric for pacing sites separated by 0-17.5 mm. Pacing sites in swine L V and RV can be distinguished when separated by >2.5 mm with good sensitivity and specificity