A simple ECG algorithm using only the R/S ratio in leads V1, V2, and aVF accurately localized accessory pathways with an overall sensitivity of 94% and specificity of 98%.
Observational (n=142)
Does a simple ECG algorithm using only the R/S ratio accurately localize accessory pathways in patients with Wolff-Parkinson-White syndrome?
A simple ECG algorithm using only the R/S ratio in leads V1, V2, and aVF provides high sensitivity and specificity for localizing accessory pathways in WPW syndrome.
Abstract Background Several algorithms for localizing accessory pathways (APs) are based on the delta wave morphology, R/S ratio, and QRS polarity. However, they are somewhat complicated, and an accurate determination of the delta wave morphology is occasionally difficult. The aims of this study were to develop a simple algorithm for localizing APs using only the R/S ratio, and to test the accuracy of the algorithm prospectively. Methods We studied 142 patients with a single anterogradely conducting AP on a 12‐lead ECG. R/S ratios were analyzed in leads V1, V2, and aVF (R/S‐V1, R/S‐V2, and R/S‐aVF). AP locations were divided into five regions based on fluoroscopic anatomy. Results A new algorithm was developed by correlating R/S‐V1, R/S‐V2, and R/S‐aVF with successful ablation sites in 88 initial consecutive patients. All 55 patients with left free wall APs showed R/S‐V1 ≥0.5, and 47 (98%) of 48 patients with left anterior or lateral APs showed R/S‐aVF ≥1. In contrast, all seven patients with left posterolateral or posterior APs showed R/S‐aVF <1. All nine patients with right‐and‐left midseptal or posteroseptal APs showed R/S‐V1 <0.5 and R/S‐V2 ≥0.5. Of 12 patients with right anterior, lateral or anteroseptal APs, 10 (83%) showed R/S‐V1 <0.5, R/S‐V2 <0.5 and R/S‐aVF ≥1. Finally, nine (75%) of 12 patients with right posterolateral or posterior APs showed R/S‐V1 <0.5, R/S‐V2 <0.5, and R/S‐aVF <1. Then this algorithm was tested prospectively in 54 patients. Overall, the sensitivity was 94%, and the specificity was 98%. Conclusions This ECG algorithm provides a simple and accurate way to identify the AP localization.
Taguchi et al. (Sun,) conducted a observational in Wolff-Parkinson-White syndrome (n=142). R/S ratio-based ECG algorithm vs. Fluoroscopic anatomy (successful ablation sites) was evaluated on Algorithm sensitivity and specificity for localizing accessory pathways. A simple ECG algorithm using only the R/S ratio in leads V1, V2, and aVF accurately localized accessory pathways with an overall sensitivity of 94% and specificity of 98%.