A Potential New Technique To Estimate the Origins of Focal Atrial Tachycardias From 12-lead Electrocardiograms - A Potential New Technique To Estimate the Origins of Focal Atrial Tachycardias From 12-lead Electrocardiograms - Open Access Pub

Background: This brief report presents a potential new technique for locating the sites of origin of focal atrial tachycardias from standard 12-lead electrocardiograms. Methods: Estimated P wave vector coordinates are derived from leads I, aVF, V1 and V2, and mapped to a three dimensional coordinate system in space. A simple graphical method is used to find the back projection of the P wave vector onto the surface of atrial muscle to estimate the most likely site of origin of the tachycardia. Results: Graphical back projection correctly identified foci of atrial tachycardias in 19 of 19 cases described in the most complete available published study. Conclusions: Clinical studies are indicated to validate this simple method for initial noninvasive evaluation of candidates for ablation therapy. This brief report presents a potential new technique for locating the sites of origin of focal atrial tachycardias from standard 12-lead electrocardiograms. Estimated P wave vector coordinates are derived from leads I, aVF, V1 and V2, and mapped to a three dimensional coordinate system in space. A simple graphical method is used to find the back projection of the P wave vector onto the surface of atrial muscle to estimate the most likely site of origin of the tachycardia. Graphical back projection correctly identified foci of atrial tachycardias in 19 of 19 cases described in the most complete available published study. Clinical studies are indicated to validate this simple method for initial noninvasive evaluation of candidates for ablation therapy. DOI10.14302/issn.2329-9487.jhc-16-931 Unifocal atrial tachycardia is an uncommon form of supraventricular tachycardia, often resistant to drug therapy, for which percutaneous radiofrequency catheter ablation is an effective treatment option.1, 2 Anatomic localization of the earliest activation site is important for effective targeting of ablation. Previous workers have proposed that analysis of P wave morphology in the standard 12-lead electrocardiogram may be a useful initial step in predicting the origin of an atrial tachycardia3, 4, 5, 6. The present study takes a fresh look at this problem to determine if better localization is possible when information from multiple electrocardiographic leads is combined in a spatial vector analysis7. Preliminary studies in computational models of impulse propagation in the atria and the resulting body surface electrocardiographic potentials were done, similar to previous work on ventricular pacing.8, 9 These studies suggested the following scheme for localizing initial atrial