Algorithms to Identify Accessory Pathways' Location on the 12-Lead Electrocardiogram

摘要

In 1945, Rosenbaum and colleagues were the first to differentiate left- and right-sided accessory pathways (AP) using the surface electrocardiogram (ECG). The early precordial leads' major QRS polarity was either positive (left sided; type A) or negative (right sided; type B). The basis of their study remains central to all subsequent algorithms in that the delta-wave polarity is negative on the ECG lead at the AP ventricular insertion. With advances in surgical ablation, the ECG characteristics of pathways were localized to more specific sites, with variable success. Endovascular ablation techniques enabled more precise localization, because the extent of surgical dissection along the annuli was no longer required. These algorithms were then developed further with the pinpoint accuracy of electroanatomic mapping. The ability to predict AP location shortens mapping time and enables prepreprocedural planning including transseptal access, angiography/venography, choice of ablation catheter, and informs risk estimate for the patient as part of the consent process. Herein, we provide an overview of selected AP localization algorithms. We also distil the findings of these studies in a simplified topographic algorithm (STA), with the interventional electrophysiologist in mind.