Accurate pre-procedural planning is crucial for successful ventricular tachycardia ablation in patients with structural heart disease. This study, presented at ESC Congress 2025, compared standard 12-lead ECG and noninvasive electrocardiographic imaging (ECGi) for predicting VT exit sites and isthmuses.

Seventeen patients (median age 71 years, 88% male) undergoing left ventricular VT ablation were included. ECGs were interpreted by general cardiologists and electrophysiologists using a validated 17-segment algorithm, while ECGi utilized a 252-electrode 3D mapping system.

Physicians correctly identified the VT exit site in 48% of cases, with electrophysiologists outperforming general cardiologists. In contrast, ECGi achieved an overall accuracy of 88% and correctly identified the exact VT exit site segment in 82% of patients. Interoperator concordance was also higher with ECGi.

When physician predictions were inaccurate, errors were most often apical rather than basal. These findings suggest ECGi offers a reliable, noninvasive tool to improve pre-procedural mapping, optimize ablation strategies, and enhance outcomes in structural heart disease patients undergoing VT ablation.