Derivation of an optimal lead set for measuring ectopic atrial activation from the pulmonary veins by using body surface mapping

Atrial fibrillation is often initiated by atrial premature beats originatin g in the pulmonary veins. Non-invasive localization of these ectopic beats would be of significant value in guiding therapy. Body surface potential ma pping was performed in nine patients undergoing invasive electrophysiologic study. Signals were recorded from 62 electrodes during pace mapping from e ach of the pulmonary veins. optimal electrodes for localizing pulmonary vei n activation were sequentially chosen. Seven optimal electrodes (6 anterior , 1 posterior) for recording ectopic atrial activation originating in the p ulmonary veins were selected. The seven optimal electrode set performed bet ter than the standard 9 electrode ECG at estimating the full body surface m ap (correlation 97 vs. 95.7%; p < 0.05). Seven optimally selected electrode s can estimate the body surface potential distribution during ectopic atria l activation originating from the pulmonary veins. The ability of this elec trode configuration to discriminate the site of origin of ectopic atrial be ats requires prospective evaluation.