Elsevier

Heart Rhythm

Volume 18, Issue 11, November 2021, Pages 1959-1965
Heart Rhythm

Clinical
Ventricular Tachycardia
Reappraisal of electrocardiographic criteria for localization of idiopathic outflow region ventricular arrhythmias

https://doi.org/10.1016/j.hrthm.2021.08.003Get rights and content

Background

Electrocardiographic (ECG) criteria have been proposed to localize the site of origin of outflow region ventricular arrhythmias (VAs). Many factors influence the QRS morphology of VAs and may limit the accuracy of these criteria.

Objective

The purpose of this study was to assess the accuracy of ECG criteria that differentiate right from left outflow region VAs and localize VAs within the aortic sinus of Valsalva (ASV).

Methods

One hundred one patients (mean age 52 ± 16 years; 55 [54%] women) undergoing catheter ablation of right ventricular outflow tract (RVOT) or ASV VAs with a left bundle branch block, inferior axis morphology were studied. ECG measurements including V2 transition ratio, transition zone index, R-wave duration index, R/S amplitude index, V2S/V3R index, V1–3 QRS morphology, R-wave amplitude in the inferior leads were tabulated for all VAs. Comparisons were made between the predicted site of origin using these criteria and the successful ablation site.

Results

Patients had successful ablation of 71 RVOT and 38 ASV VAs. For the differentiation of RVOT from ASV VAs, the positive predictive values and negative predictive values for all tested ECG criteria ranged from 42% to 75% and from 71% to 82%, respectively, with the V2S/V3R index having the largest area under the curve of 0.852. Morphological QRS criteria in leads V1 through V3 did not localize ASV VAs. The maximum R-wave amplitude in the inferior leads was the sole criterion demonstrating a significant difference between right ASV, right-left ASV commissure, and left ASV sites.

Conclusion

ECG criteria for differentiating right from left ventricular outflow region VAs and for localizing ASV VAs have a limited accuracy.

Introduction

The right ventricular outflow tract (RVOT) and left ventricular (LV) outflow region are common sites of origin (SOOs) for idiopathic ventricular arrhythmias (VAs)1 that can be successfully treated using catheter ablation.2,3 Multiple electrocardiographic (ECG) criteria to differentiate between VAs that arise from the RVOT and the LV outflow region have been described.4, 5, 6, 7, 8, 9, 10, 11 Additional ECG features have also been reported to localize VAs to a specific aortic sinus of Valsalva (ASV) or the right-left ASV commissure.12, 13, 14 ECG-guided localization of outflow region VAs has important procedural implications with regard to vascular access, catheter selection, anticoagulation administration, procedure time, and complication risks.4,15, 16, 17 The accuracy of ECG criteria may be limited by factors including the attitudinal position of the outflow regions in the chest cavity, lead position, chest wall deformities, and preferential conduction.6,18,19 In this study, we sought to reappraise previously reported ECG criteria and determine their accuracy in predicting the successful site of ablation of idiopathic VAs with a left bundle branch block (LBBB), inferior axis morphology.

Section snippets

Study population

The subjects of this retrospective study comprised 101 patients who had undergone catheter ablation of idiopathic VAs (85 [84%] presenting as premature ventricular complexes (PVCs) and 17 [16%] as sustained or nonsustained focal ventricular tachycardia) arising from the RVOT or ASV with a LBBB, inferior axis morphology at a single institution between June 2014 and June 2018. Baseline demographic data were collected by chart abstraction. The study was approved by the Institutional Review Board

Clinical characteristics

One hundred one patients (mean age 52 ± 16 years; range 22–90 years; 54 women [53%]) who underwent successful CA of 109 idiopathic outflow region VAs comprised the study population. Of the 109 VAs, 38 (35%) were successfully ablated from the ASV and 71 (65%) were successfully ablated from the RVOT. Among the 71 patients in the RVOT group, ablation was most commonly performed below the pulmonic valve (77%). Ablation above the pulmonic valve and on both sides of the valve was performed in 7% and

Discussion

In this study, we report the utility of reported ECG criteria for localization of idiopathic outflow region VAs with a LBBB, inferior axis morphology. The main findings of this study include the following: (1) the current published ECG criteria to differentiate ASV from RVOT VAs have limited discriminative ability, with positive predictive values ranging between 42% and 75%; (2) among the ECG criteria assessed, the V2S/V3R index had the largest ROC AUC; and (3) morphological criteria for

Conclusion

Our study of previously reported ECG criteria to differentiate the SOO of VAs between the ASV and the RVOT and localize ASV VAs to a particular sinus suggests that these criteria have a limited accuracy. Many factors such as variability in the proximity of the RVOT and ASV, attitudinal position of the outflow regions in the chest cavity, ablation approach, and ECG lead positioning contribute to the limitations of the ECG to precisely localize the SOO of outflow region VAs.

References (30)

  • T. Yamada et al.

    Prevalence and clinical, electrocardiographic, and electrophysiologic characteristics of ventricular arrhythmias originating from the noncoronary sinus of Valsalva

    Heart Rhythm

    (2013)
  • J. Acosta et al.

    Impact of earliest activation site location in the septal right ventricular outflow tract for identification of left vs right outflow tract origin of idiopathic ventricular arrhythmias

    Heart Rhythm

    (2015)
  • Y. Tahara et al.

    Evaluation of the electrocardiographic transitional zone by cardiac computed tomography

    J Electrocardiol

    (1991)
  • J.W. Cheung et al.

    Catheter ablation of arrhythmias originating from the left ventricular outflow tract

    JACC Clin Electrophysiol

    (2019)
  • R.D. Anderson et al.

    Modified precordial lead R-wave deflection Interval predicts left- and right-sided idiopathic outflow tract ventricular arrhythmias

    JACC Clin Electrophysiol

    (2020)

    • Cited by (0)

    Funding sources: The authors have no funding sources to disclose.

    Disclosures: Dr Cheung has received consulting fees from Abbott and Boston Scientific and fellowship grant support from Abbott, Biosense, and Boston Scientific. The rest of the authors report no conflicts of interest.

    View full text
    © 2021 Heart Rhythm Society. All rights reserved.