The purpose of this study is to evaluate a novel non-invasive cardiac electric imaging methodology for localizing and imaging cardiac electrical activity from body surface electrocardiographic recordings in patients with ventricular tachycardia (VT). Using non-invasive means will increase our ability to correctly diagnose cardiac abnormalities, and aid ablation of cardiac arrhythmias, offering enhanced performance to what currently exists.

Specific Aims

1. Use non-invasive cardiac electric imaging to provide information as to the sites of origin of arrhythmias and sequence of cardiac activation and repolarization.

Methods and Procedures Approximately 8 patients with recorded Premature Ventricular Contractions (PVC), Wolff-Parkinson-White (WPW) or other ventricular tachycardia cases which need Ensite/Carto endocardial mapping and radiofrequency ablation treatment will be enrolled.

One day before catheterization and ablation, patients will undergo approximately 30 minutes of Body Surface Potential Mapping (BSPM) recordings with about 200 surface electrodes arranged in 20 strips, attached on his/her front and back. BSPMs will be recorded in the baseline resting rhythm.

On the day of ablation, before catheterization in the surgical room, the BSPM recording procedure will be carried out with the patient using the same technique used during the first BSPM study.

Clinical endocardial mapping data may also be obtained concurrently with BSPM recordings before the ablation procedure.

Another BSPM recording will be made 30-60 minutes after successful ablation with the patient still in normal sinus rhythm if possible. Patients will be followed up 1 month after ablation with the same method of BSPM recorded at the baseline resting rhythm.

Any patient undergoing ablation.