Utility of automated template matching for the interpretation of pace mapping in patients ablated due to outflow tract ventricular arrhythmias.
OBJECTIVE
One of the disadvantages of classic pace mapping (PM) is the operator's subjective interpretation. The aim of this single-centre retrospective study was to evaluate the value of automated template matching (AMT) in patients ablated due to ventricular outflow tract arrhythmias (OTAs).


RESULTS
From an overall group of 105 patients with OTA who were scheduled for transcatheter ablation (TA), AMT was accessible in 42 patients [21 right ventricular outflow tract (RVOT), 21 left ventricular outflow tract (LVOT), 28 women, aged 51.5 ± 12.7 years]. We used AMT to compare spontaneous arrhythmia ORS (spontQRS) with paced QRS complexes during PM in sites where radiofrequency (RF) applications were successful and in sites where RF applications were unsuccessful. The concordance was presented in per cents as objective matching scores (OMS). Then, at the successful ablation sites, we examined the relationship between OMS and the visual interpretation of PM was presented as electrophysiologists matching scores (EMS). The OMS of PM at sites of successful ablation varied from 78 to 99% (mean 94.1 ± 3.8) and from 47 to 95% (mean 80.2 ± 12.6%) at sites of unsuccessful ablation. Pace mapping in unsuccessful RF sites was significantly less similar to spontQRS morphologies than in successful RF sites (P = 0.0001). There was a significant correlation between OMS and EMS (r = 0.82; P < 0.0001). The OMS that indicated optimal ablation site was 89% (sensitivity = 95%; specificity = 80%). The mean OMS for successful sites at RVOT (95.1 ± 1.8%) and LVOT (93.1 ± 4.9%) were not different (P = 0.0551).


CONCLUSIONS
This analysis revealed that AMT is a valuable technique for the interpretation of PM and for the identification of successful ablation sites in OTA.
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland rafalkuteszko@wp.pl.
Rafal
R
Kuteszko
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Mariusz
M
Pytkowski
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Michal M
MM
Farkowski
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Aleksander
A
Maciag
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Maciej
M
Sterlinski
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Agnieszka
A
Jankowska
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Ilona
I
Kowalik
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Dariusz
D
Zajac
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Bohdan
B
Firek
Department of Coronary and Structural Heart Diseases, Institute of Cardiology, Warsaw, Poland.
Marcin
M
Demkow
The Second Department of Coronary Artery Disease, Institute of Cardiology, 1 Spartanska Street, Warsaw 02-637, Poland.
Hanna
H
Szwed
D000328:Adult; D017115:Catheter Ablation / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010363:Pattern Recognition, Automated; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D017180:Tachycardia, Ventricular / Q000601:surgery*
Automated template matching; Catheter ablation; Pace mapping; Ventricular outflow tract; Ventricular tachycardia