New algorithm for accessory pathway localization focused on screening septal pathways in pediatric patients with Wolff-Parkinson-White syndrome

A Novel ECG Algorithm for Accurate Localization of Manifest Accessory Pathways in Both Children and Adults: SMART-WPW

BACKGROUND

Accessory pathway (AP) ablation is an established therapy for patients with Wolff-Parkinson-White (WPW) syndrome. An accurate 12-lead electrocardiogram (ECG) based identification of the AP location is crucial for an optimized risk assessment and ablation.

OBJECTIVE

This study aimed to develop and validate a simplified 12-lead ECG algorithm for accurate localization of AP in WPW syndrome, to improve procedural risk assessment, ablation planning, and outcomes.

METHODS

In this multicenter study, 260 patients with a single manifest AP undergoing WPW ablation enrolled. The SMART-WPW algorithm was developed and prospectively tested and compared to established Pambrun and Arruda algorithms. The novel SMART-WPW algorithm allows for a stepwise localization of 12 ablation targets, which are displayed on a clock representation.

RESULTS

SMART-WPW algorithm correctly identified the AP in 253 of 260 patients (97%) (mean age 34±19 years; 51% female), with a sensitivity of 96%, specificity of 100%, PPV of 95%, and NPV of 100%. High accuracy was achieved for right-sided APs between 4-8 o'clock (100% sensitivity and specificity) and for left-sided APs between 5-8 o'clock (100% sensitivity and specificity). The SMART-WPW algorithm outperformed the Pambrun (97% vs. 90%, p=0.015) and Arruda algorithms (97% vs. 73%, p<0.001). In a subgroup of children under 18 (n=76; mean age 14±3 years; 61% female), the algorithm showed higher accuracy than the Arruda algorithm (97% vs. 62%, p<0.001).

CONCLUSION

The SMART-WPW algorithm is an accurate, efficient, and reproducible tool for 12-lead ECG-based AP localization. Its use may enhance preprocedural assessment and ablation planning in WPW syndrome.

Risk stratification and management of arrhythmias in patients with Wolff-Parkinson-White syndrome

Wolff-Parkinson-White (WPW) syndrome is a cardiac disorder characterized by an accessory pathway known as the bundle of Kent, which bypasses the atrioventricular node and predisposes patients to tachyarrhythmias, including supraventricular tachycardia and atrial fibrillation. The prevalence of WPW syndrome ranges from 0.1% to 0.5% globally, with a higher incidence in males and diagnosis typically occurring between ages 10 and 30. Although many individuals remain asymptomatic, WPW presents a risk of life-threatening arrhythmias, including sudden cardiac death, particularly when atrial fibrillation progresses to ventricular fibrillation (VF). Effective risk stratification is essential for managing WPW syndrome; this involves evaluating symptomatic presentation, accessory pathway properties, and underlying cardiac conditions using clinical, electrocardiographic, and electrophysiological data. Recent advances in risk stratification models enable clinicians to identify better patients at high risk for arrhythmia recurrence or sudden death, informing treatment strategies such as catheter ablation. This study emphasizes the importance of personalized risk assessment in guiding therapeutic decisions, minimizing unnecessary interventions, and improving outcomes. This review's novel contribution lies in its updated analysis of risk stratification models, which incorporates new research on the genetic and epidemiological factors influencing WPW syndrome. This analysis emphasizes the evolving role of catheter ablation as a first-line treatment for high-risk patients, demonstrating its potential to provide long-term arrhythmia control with minimal complications. Our findings underscore the necessity for ongoing post-ablation surveillance to monitor for recurrence and to optimize patient care, ultimately improving clinical outcomes.

Characteristics of Right-Sided Accessory Pathways Associated With Right Cardiac Veins

BACKGROUND

The anatomy of myocardial fibers around the right cardiac veins (RCVs) and their roles in accessory pathways (APs) are rarely reported.

METHODS

Six RCV-APs were identified from 566 patients with right-sided APs. Mapping of retrograde atrial activation was performed using CARTO 3 system under orthodromic tachycardia or right ventricular pacing. Venography of RCVs was acquired at the earliest retrograde atrial activation.

RESULTS

Patients enrolled had a median age of 30 (11-51) years, 5 of them were male. Venography of RCVs could be classified into 3 distinct patterns based on the identified ventricular branches, right marginal vein only (type I; n=3), both right marginal vein and anterior cardiac veins (type II; n=2), and anterior cardiac vein only (type III; n=1). Patients with type I venography had rS QRS pattern in lead V1, negative delta wave in lead III and negative or isoelectric delta wave in lead aVF. However, patients with type II and III venography had QS QRS patterns in lead V1 and variable patterns of delta wave in inferior leads. Earliest retrograde atrial activation was found at a median of 16.75 (14.60-20.00) mm away from the tricuspid annulus, all with A larger than V. At the earliest retrograde atrial activation, far-field ventricular electrogram was found 30 ms later than QRS onset in 1 patient under sinus rhythm. AP conduction was eliminated by mechanical pressure in 2 and by radiofrequency ablation in 4 at the ostium of the veins colocalizing with the earliest retrograde activation of the right atrium. No recurrence was observed during 36 (10-60) months follow-up.

CONCLUSIONS

The RCV-AP is a rare form of right-sided APs characterized by atrial insertions distant from the annulus. ECG-speculated ventricular insertion sites conformed to the location of identified RCVs.

Wolf-Parkinson-White Syndrome: Diagnosis, Risk Assessment, and Therapy-An Update

Wolf-Parkinson-White (WPW) syndrome is a disorder characterized by the presence of at least one accessory pathway (AP) that can predispose people to atrial/ventricular tachyarrhythmias and even sudden cardiac death. It is the second most common cause of paroxysmal supraventricular tachycardia in most parts of the world, affecting about 0.1-0.3% of the general population. Most patients with WPW syndrome have normal anatomy, but it may be associated with concomitant congenital heart disease or systemic diseases. Although many individuals are asymptomatic, during supraventricular arrhythmia episodes, they may experience severe symptoms, including syncope or even sudden cardiac death (mainly due to pre-excited atrial fibrillation over rapidly conducting AP). In addition to arrhythmia-related symptoms, for some specific locations of the APs with overt anterograde conduction, there might be a reduction in exercise capacity mediated by a reduction in LV systolic performance due to anomalous LV depolarization. Although it is typically diagnosed through electrocardiography (ECG), additional tests are necessary for risk assessment. Management of WPW syndrome may be quite challenging and can vary from only acknowledging the presence of the accessory pathway to pharmacological treatment or radiofrequency ablation. Early diagnosis, risk assessment, and appropriate treatment are critical steps in the management of WPW syndrome, aiming to improve the quality of life and reduce the risk of life-threatening arrhythmias.

Diagnosis and treatment of fetal and pediatric age patients (0-12 years) with Wolff-Parkinson-White syndrome and atrioventricular accessory pathways

Overt or concealed accessory pathways are the anatomic substrates of ventricular preexcitation (VP), Wolff-Parkinson-White syndrome (WPW) and paroxysmal supraventricular tachycardia (PSVT). These arrhythmias are commonly observed in pediatric age. PSVT may occur at any age, from fetus to adulthood, and its symptoms range from none to syncope or heart failure. VP too can range from no symptoms to sudden cardiac death. Therefore, these arrhythmias frequently need risk stratification, electrophysiologic study, drug or ablation treatment. In this review of the literature, recommendations are given for diagnosis and treatment of fetal and pediatric age (≤12 years) WPW, VP, PSVT, and criteria for sport participation.

The Wolff-Parkinson-White pattern in neonates: results from a large population-based cohort study

AIMS

Wolff-Parkinson-White (WPW) syndrome is a conduction disorder characterized by an accessory electrical pathway between the atria and ventricles, which may predispose to supraventricular tachycardia (SVT) and sudden cardiac death. It can be seen as an isolated finding or associated with structural heart disease. Our aims were to determine the prevalence of a WPW pattern in a large and unselected cohort of neonates and to describe the electro- and echocardiographic characteristics as well as the natural history during early childhood.

METHODS AND RESULTS

Electrocardiograms and echocardiograms of neonates (aged 0-30 days) from a large, prospective, population-based cohort study were included. Neonates with a WPW pattern were identified and matched 1:4 to controls. Localization of the accessory pathway was assessed by different algorithms. Among 17 489 neonates, we identified 17 (76% boys) with a WPW pattern consistent with a prevalence of 0.1%. One neonate had moderate mitral regurgitation while other echocardiographic parameters were similar between cases and controls (all P > 0.05). The accessory pathways were primarily predicted to be left-sided. At follow-up (available in 14/17 children; mean age 3.2 years) the pre-excitation pattern persisted in only four of the children and none of the children had experienced any episodes of SVT.

CONCLUSION

The prevalence of a WPW pattern in our cohort of unselected neonates was 0.1%. The WPW pattern was more frequent in boys and generally not associated with structural heart disease, and the accessory pathways were primarily left-sided. At follow-up, the WPW pattern had disappeared in most of the children suggesting either an intermittent nature or that normalization occurs.

CLINICAL TRIAL REGISTRATION

Copenhagen Baby Heart, NCT02753348.

Accuracy of Algorithms Predicting Accessory Pathway Localization in Pediatric Patients with Wolff-Parkinson-White Syndrome

We aimed to assess the accuracy of determining accessory pathway (AP) localization from 12 lead ECG tracings by applying 12 different algorithms in pediatric patients diagnosed with Wolff-Parkinson-White syndrome. We compared algorithm accuracy in electrophysiologic study ECG tracings with full preexcitation and resting ECG tracings. The assessing pediatric cardiologists were blinded regarding EP study results on AP localization. For exact AP location, the algorithms published by D'Avila et al. and Boersma et al. yielded the highest accuracy (58%). Distinguishing laterality, the median accuracy for predicting left or right-sided APs was 74%, while for septal APs it was 68%. We conclude that algorithms predicting AP location in pediatric patients with Wolff-Parkinson-White syndrome show low accuracy for exact AP localization. For laterality, however, accuracy was significantly higher.

EASY-WPW: a novel ECG-algorithm for easy and reliable localization of manifest accessory pathways in children and adults

AIMS

Accessory pathway (AP) ablation is a standard procedure for the treatment of Wolff-Parkinson-White syndrome (WPW). Twelve-lead electrocardiogram (ECG)-based delta wave analysis is essential for predicting ablation sites. Previous algorithms have shown to be complex, time-consuming, and unprecise. We aimed to retrospectively develop and prospectively validate a new, simple ECG-based algorithm considering the patients' heart axis allowing for exact localization of APs in patients undergoing ablation for WPW.

METHODS AND RESULTS

Our multicentre study included 211 patients undergoing ablation of a single manifest AP due to WPW between 2013 and 2021. The algorithm was developed retrospectively and validated prospectively by comparing its efficacy to two established ones (Pambrun and Arruda). All patients (32 ± 19 years old, 47% female) underwent successful pathway ablation. Prediction of AP-localization was correct in 197 patients (93%) (sensitivity 92%, specificity 99%, PPV 96%, and NPV 99%). Our algorithm was particularly useful in correctly localizing antero-septal/-lateral (sensitivity and specificity 100%) and posteroseptal (sensitivity 98%, specificity 92%) AP in proximity to the tricuspid valve. The accuracy of EASY-WPW was superior compared to the Pambrun (93% vs. 84%, P = 0.003*) and the Arruda algorithm (94% vs. 75%, P < 0.001*). A subgroup analysis of children (n = 58, 12 ± 4 years old, 55% female) revealed superiority to the Arruda algorithm (P < 0.001*). The reproducibility of our algorithm was excellent (ϰ>0.8; P < 0.001*).

CONCLUSION

The novel EASY-WPW algorithm provides reliable and accurate pre-interventional ablation site determination in WPW patients. Only two steps are necessary to locate left-sided AP, and three steps to determine right-sided AP.

Is there a need for a novel algorithm for accessory pathways localization?

Wolff Parkinson White Syndrome (WPW) affects between 0.1% and 0.2% of the population, causes morbidity due to supraventricular tachycardia (SVT) and can lead to sudden cardiac arrest [1-3]. This article is protected by copyright. All rights reserved.