Intermittent preexcitation indicates "a low-risk" accessory pathway: Time for a paradigm shift?

2024 HRS expert consensus statement on arrhythmias in the athlete: Evaluation, treatment, and return to play

Youth and adult participation in sports continues to increase, and athletes may be diagnosed with potentially arrhythmogenic cardiac conditions. This international multidisciplinary document is intended to guide electrophysiologists, sports cardiologists, and associated health care team members in the diagnosis, treatment, and management of arrhythmic conditions in the athlete with the goal of facilitating return to sport and avoiding the harm caused by restriction. Expert, disease-specific risk assessment in the context of athlete symptoms and diagnoses is emphasized throughout the document. After appropriate risk assessment, management of arrhythmias geared toward return to play when possible is addressed. Other topics include shared decision-making and emergency action planning. The goal of this document is to provide evidence-based recommendations impacting all areas in the care of athletes with arrhythmic conditions. Areas in need of further study are also discussed.

"On-Off" phenomenon in a case of concealed left lateral atrio-ventricular accessory pathway - What is the mechanism?

We report a case of symptomatic supraventricular tachycardia who had absent VA conduction during electrophysiology study. The interesting finding was appearance of VA conduction only at a specific cycle length of ventricular pacing which reproducibly induced a sustained orthodromic re-entrant tachycardia (ORT). We review the literature and conclude that supernormal AP conduction can explain such phenomenon.

Risk assessment in patients with symptomatic and asymptomatic pre-excitation

AIMS

Controversy remains as to whether the exercise stress test (EST) is sufficient for risk evaluation in patients with pre-excitation. This study aims to clarify the usefulness of EST in risk stratification in both asymptomatic and symptomatic patients presenting with pre-excitation.

METHODS AND RESULTS

This prospective study includes consecutive asymptomatic and symptomatic patients with pre-excitation referred for risk assessment. All participants performed an incremental EST (bicycle) prior to an electrophysiology study (EPS). Primary data from the EST included loss of pre-excitation during exercise, and primary data from the EPS included the measurement of accessory pathway effective refractory period (APERP), shortest pre-excited RR interval (SPERRI), and inducible arrhythmia with the use of a beta-adrenergic receptor agonist if deemed necessary. One hundred and sixty-four patients (59 asymptomatic, 105 symptomatic) completed an EST and EPS. Forty-five patients (27%) demonstrated low-risk findings on EST, of which 19 were asymptomatic and 26 were symptomatic. Six patients with low-risk EST findings had SPERRI/APERP ≤ 250 ms at EPS, and two of them were asymptomatic. The sensitivity, specificity, positive predictive value, negative predictive value (NPV), and accuracy of low-risk EST for excluding patients with SPERRI/APERP ≤ 250 ms were 40, 91, 87, 51, and 60%, respectively. The number of patients with inducible arrhythmia at EPS was similar in the asymptomatic (36, 69%) and symptomatic (73, 61%) groups.

CONCLUSION

Sudden loss of pre-excitation during EST has a low NPV in excluding high-risk APs. The EPS with the use of isoproterenol should be considered to accurately assess the risk of patients with pre-excitation regardless of symptoms (ClinicalTrials.gov Identifier: NCT03301935).

Intermittent ventricular pre-excitation in symptomatic adults: Always a marker of low risk?

BACKGROUND

Intermittent ventricular pre-excitation was considered a low-risk marker for sudden death. However, to date, some studies do not exclude the existence of accessory pathways (APs) with high-risk intermittent antegrade conductive properties. According to current European Guidelines, high-risk features of APs are antegrade pathway conduction ≤250 ms in baseline or during the adrenergic stimulus, inducibility of atrioventricular reciprocating tachycardias (AVRT), inducibility of pre-excited atrial fibrillation (AF), and presence of multiple APs. For all of these transcatheter ablation is recommended. The aim of our study was to evaluate the existence of differences in risk characteristics between patients with intermittent pre-excitation (IPX) and those with persistent pre-excitation (PPX), from a sample of adults with ventricular pre-excitation and symptoms like palpitations.

METHODS

293 adults [IPX: 51 (17.4%); PPX: 242 (82.6%)] underwent electrophysiological study and then catheter ablation of their APs if arrhythmia inducibility (AVRT/AF) was noted, or, conversely, if it was appreciated a fast AP antegrade conduction, in baseline or during intravenous isoproterenol infusion, or if multiple APs were detected.

RESULTS

There were no statistically significant differences in demographic characteristics (age and gender), AVRT/AF inducibility, antegrade conductive properties, the prevalence of multiple APs, and APs locations between IPX and PPX patients.

CONCLUSIONS

In our study, patients with IPX did not show significant differences in clinical and electrophysiological features versus PPX patients.

Management of Young Athletes with Asymptomatic Preexcitation-A Review of the Literature

INTRODUCTION

The management of young athletes with asymptomatic preexcitation remains a challenge, regardless of the progress we have made in understanding the basis of condition and developing catheter ablation procedures. The risk of sudden death, however small, yet definite, being the first symptom is determining our approach. The aim of the study was to establish the current state of knowledge regarding the management of young athletes diagnosed with asymptomatic preexcitation, by conducting a literature review.

MATERIAL AND METHODS

A comprehensive literature review was completed in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search was limited to English language publications using the following search terms: "asymptomatic" or "incidental" and "pre-excitation" or "Wolff-Parkinson-White" or "delta wave" and "athlete" or "sport". The search was supplemented by hand review of the bibliographies of previous relevant systematic reviews.

RESULTS

The search resulted in 85 of abstracts, and the manual search of the bibliographies resulted in 24 additional papers. After careful analysis 10 publications were included in the review. In all but one of the presented papers, the authors used non-invasive methods and then either trans-esophageal or invasive EPS as a way to risk stratify asymptomatic patients. Evidence of rapid conduction through the accessory pathway was considered high risk and prompted sport disqualification. In the analysed reports there were combined: 142 episodes of the life-threatening events (LTE)/sudden death (SCD), of which 56 were reported to occur at rest, 61 during activity and no data were available for 25.

CONCLUSIONS

athletic activity may impose an increased risk of life-threatening arrhythmias in patients with asymptomatic preexcitation; hence, a separate approach could be considered, especially in patients willing to engage in high-intensity, endurance and competitive sports.

What Have We Learned from the European Society of Cardiology 2019 Guidelines on Supraventricular Tachycardia

Supraventricular tachycardias (SVTs) are common arrhythmic conditions in clinical practice. Increased knowledge and experience on SVTs and some unclear situations in clinical practice led the European Society of Cardiology (ESC) team to write a new guideline. In this review, we touch upon the important points in the new ESC 2019 SVT guidelines and present changing approaches and suggestions. By providing a general review on SVTs, we also mention the basic mechanism, epidemiology, and clinical presentation of SVTs, approaching narrow and wide QRS tachycardias, SVTs in special patient groups, and treatment of SVTs.

Intermittent preexcitation indicates "a low-risk" accessory pathway: Time for a paradigm shift?

We report three patients with intermittent loss of the preexcitation pattern in the ECG that had undergone an electrophysiological study. Despite apparently poorly conducting accessory pathway (AP), in each case a fast anterograde conduction, either during spontaneous atrial fibrillation or during incremental atrial pacing (on isoproterenol) was documented; shortest preexcited RR intervals of 200-240 ms were observed. We review the literature and conclude that intermittent preexcitation observed on resting 12-lead ECG lacks sufficient specificity for the diagnosis of an AP with long refractory period and cannot be considered a substitute for electrophysiological study in patients with this electrocardiographical phenomenon.