Accessory pathway localization with probabilistic density maps generated
by a mobile application: Validation of a full preexcitation net-vector
method
Abstract
Introduction. Precise electrocardiographic localization of
accessory pathways (AP) can be challenging. Seminal AP localization
studies were limited by complexity of algorithms and sample size.We
aimed to create a non-algorithmic method for AP localization based on
color-coded maps of AP distribution generated by a web-based
application. Methods. APs were categorized into 19
regions/types based on invasive electrophysiologic mapping. Preexcited
QRS complexes were categorized into 6 types based on polarity and
notch/slur. For each QRS type in each lead the distribution of APs was
visualized on a gradient map. The principle of common set was used to
combine the single lead maps to create the distribution map for AP with
any combination of QRS types in several leads. For the validation phase,
a separate cohort of APs was obtained. Results. A total of 804
patients with overt APs were studied. The application used the
exploratory dataset of 552 consecutive APs and the corresponding QRS
complexes to generate AP localization maps for any possible combination
of QRS types in 12 leads. Optimized approach (on average 3 steps) for
evaluation of preexcited ECG was developed. The area of maximum
probability of AP localization was pinpointed by providing the QRS type
for the subsequent leads. The exploratory dataset was validated with the
separate cohort of APs (n = 260); p = 0.23 for difference in AP
distribution. Conclusions. In the largest dataset of APs
to-date, a novel probabilistic and semi-automatic approach to
electrocardiographic localization of APs was highly predictive for
anatomic localization.