Stress and pharmacologic tests as methods to identify patients with Wolff-Parkinson-White syndrome at risk of sudden death

Recommendations for participation in leisure-time physical activity and competitive sports in patients with arrhythmias and potentially arrhythmogenic conditions: Part 1: Supraventricular arrhythmias. A position statement of the Section of Sports Cardiology and Exercise from the European Association of Preventive Cardiology (EAPC) and the European Heart Rhythm Association (EHRA), both associations of the European Society of Cardiology

Symptoms attributable to arrhythmias are frequently encountered in clinical practice. Cardiologists and sport physicians are required to identify high-risk individuals harbouring such conditions and provide appropriate advice regarding participation in regular exercise programmes and competitive sport. The three aspects that need to be considered are: (a) the risk of life-threatening arrhythmias by participating in sports; (b) control of symptoms due to arrhythmias that are not life-threatening but may hamper performance and/or reduce the quality of life; and (c) the impact of sports on the natural progression of the underlying arrhythmogenic condition. In many cases, there is no unequivocal answer to each aspect and therefore an open discussion with the athlete is necessary, in order to reach a balanced decision. In 2006 the Sports Cardiology and Exercise Section of the European Association of Preventive Cardiology published recommendations for participation in leisure-time physical activity and competitive sport in individuals with arrhythmias and potentially arrhythmogenic conditions. More than a decade on, these recommendations are partly obsolete given the evolving knowledge of the diagnosis, management and treatment of these conditions. The present document presents a combined effort by the Sports Cardiology and Exercise Section of the European Association of Preventive Cardiology and the European Heart Rhythm Association to offer a comprehensive overview of the most updated recommendations for practising cardiologists and sport physicians managing athletes with supraventricular arrhythmias, and provides pragmatic advice for safe participation in recreational physical activities, as well as competitive sport at amateur and professional level. A companion text on recommendations in athletes with ventricular arrhythmias, inherited arrhythmogenic conditions, pacemakers and implantable defibrillators is published as Part 2 in Europace.

Sports Activity and Arrhythmic Risk in Cardiomyopathies and Channelopathies: A Critical Review of European Guidelines on Sports Cardiology in Patients with Cardiovascular Diseases

The prediction and prevention of sudden cardiac death is the philosopher’s stone of clinical cardiac electrophysiology. Sports can act as triggers of fatal arrhythmias and therefore it is essential to promptly frame the athlete at risk and to carefully evaluate the suitability for both competitive and recreational sports activity. A history of syncope or palpitations, the presence of premature ventricular complexes or more complex arrhythmias, a reduced left ventricular systolic function, or the presence of known or familiar heart disease should prompt a thorough evaluation with second level examinations. In this regard, cardiac magnetic resonance and electrophysiological study play important roles in the diagnostic work-up. The role of genetics is increasing both in cardiomyopathies and in channelopathies, and a careful evaluation must be focused on genotype positive/phenotype negative subjects. In addition to being a trigger for fatal arrhythmias in certain cardiomyopathies, sports also play a role in the progression of the disease itself, especially in the case arrhythmogenic right ventricular cardiomyopathy. In this paper, we review the latest European guidelines on sport cardiology in patients with cardiovascular diseases, focusing on arrhythmic risk stratification and the management of cardiomyopathies and channelopathies.

Clinical Approach to Symptomatic and Asymptomatic Patients with Ventricular Pre-excitation

Despite extensive knowledge of the physiopathology of ventricular pre-excitation, management of asymptomatic patients with this condition remains controversial.

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.

Comparison of Electrophysiologic Profiles in Pediatric Patients with Incidentally Identified Pre-Excitation Compared with Wolff-Parkinson-White Syndrome

The rising utilization of screening electrocardiograms has resulted in increased incidental identification of ventricular pre-excitation in pediatric patients. We compared accessory pathways of incidentally identified pre-excitation to Wolff-Parkinson-White Syndrome (WPW) with the aim to identify factors important in preprocedural counseling and planning. This single-center, retrospective study of patients ≤18 years without congenital heart disease identified 227 patients diagnosed with pre-excitation and referred for invasive electrophysiology study between 2008 and 2017. WPW Syndrome was diagnosed in 178 patients, while 49 patients had incidental identification of pre-excitation. Anterograde conduction of incidentally identified accessory pathways was not clinically different between the two cohorts at baseline or upon isoproterenol infusion. However, the proportion of accessory pathways meeting high-risk criteria was significantly lower than in patients diagnosed with WPW, 12% versus 28% (p < 0.05). Retrograde conduction at baseline of incidentally diagnosed accessory pathways was slower with a median block cycle length 365 milliseconds (IQR 260 to 450) versus 290 milliseconds (IQR 260 to 330, p < 0.01). In the incidentally identified cohort, right-sided, paraHisian, and fascicular pathways were more common with fewer attempted ablations (71% vs 94%, p < 0.001) and lower success rate (91% vs 97%, p < 0.001). A binomial logistic regression analysis further indicated patients incidentally identified with pre-excitation were associated with having lower rates of inducible supraventricular tachycardia, atrial fibrillation, and ablations performed, in addition, to having right-sided pathways. In conclusion, as patients with incidentally identified pre-excitation present more frequently for consideration of invasive electrophysiology study, these results impact procedural approaches, technical considerations, patient counseling, and outcome expectations.

Asymptomatic Ventricular Pre-excitation: Between Sudden Cardiac Death and Catheter Ablation

Debate about the best clinical approach to the management of asymptomatic patients with ventricular pre-excitation and advice on whether or not to invasively stratify and ablate is on-going. Weak evidence about the real risk of sudden cardiac death and the potential benefit of catheter ablation has probably prevented the clarification of action in this not infrequent and sometimes conflicting clinical situation. After analysing all available data, real evidence-based medicine could be the alternative strategy for managing this group of patients. According to recent surveys, most electrophysiologists invasively stratify. Based on all accepted risk factors - younger age, male, associated structural heart disease, posteroseptal localisation, ability of the accessory pathway to conduct anterogradely at short intervals of ≤250 milliseconds and inducibility of sustained atrioventricular re-entrant tachycardia and/or atrial fibrillation - a shared decisionmaking process on catheter ablation is proposed.

Wolff-Parkinson-White syndrome: a single exercise stress test might be misleading

Risk stratification of patients with Wolff-Parkinson-White syndrome for sudden death is a complex process, particularly in understanding the utility of the repeat exercise stress test. We report a case of an 18-year-old patient who was found to have a high-risk pathway by both invasive and exercise stress testing after an initial exercise stress test showing beat-to-beat loss of pre-excitation.

Wolff-Parkinson-White syndrome: lessons learnt and lessons remaining

The Wolff-Parkinson-White pattern refers to the electrocardiographic appearance in sinus rhythm, wherein an accessory atrioventricular pathway abbreviates the P-R interval and causes a slurring of the QRS upslope - the "delta wave". It may be asymptomatic or it may be associated with orthodromic reciprocating tachycardia; however, rarely, even in children, it is associated with sudden death due to ventricular fibrillation resulting from a rapid response by the accessory pathway to atrial fibrillation, which itself seems to result from orthodromic reciprocating tachycardia. Historically, patients at risk for sudden death were characterised by the presence of symptoms and a shortest pre- excited R-R interval during induced atrial fibrillation <250 ms. Owing to the relatively high prevalence of asymptomatic Wolff-Parkinson-White pattern and availability of catheter ablation, there has been a need to identify risk among asymptomatic patients. Recent guidelines recommend invasive evaluation for such patients where pre-excitation clearly does not disappear during exercise testing. This strategy has a high negative predictive value only. The accuracy of this approach is under continued investigation, especially in light of other considerations: Patients having intermittent pre-excitation, once thought to be at minimal risk may not be, and the role of isoproterenol in risk assessment.

Recommendations for participation in leisure-time physical activity and competitive sports in patients with arrhythmias and potentially arrhythmogenic conditions Part I: Supraventricular arrhythmias and pacemakers

This document by the Study Group on Sports Cardiology of the European Society of Cardiology extends on previous recommendations for sports participation for competitive athletes by also incorporating guidelines for those who want to perform recreational physical activity. For different supraventricular arrhythmias and arrhythmogenic conditions, a description of the relationship between the condition and physical activity is given, stressing how arrhythmias can be influenced by exertion or can be a reflection of the (patho)physiological cardiac adaptation to sports participation itself. The following topics are covered in this text: sinus bradycardia; atrioventricular nodal conduction disturbances; pacemakers; atrial premature beats; paroxysmal supraventricular tachycardia without pre-excitation; pre-excitation, asymptomatic or with associated arrhythmias (i.e. Wolff-Parkinson-White syndrome); atrial fibrillation; and atrial flutter. A related document discusses ventricular arrhythmias, channelopathies and implantable cardioverter defibrillators.

The Wolf-Parkinson-White ECG Pattern - Assessing the Mortality Risk

The presence of a Wolf-Parkinson-White (WPW) pattern is not uncommonly discovered on a life insurance applicant's ECG. How does one determine the appropriate mortality risk in this population? This article will discuss the risk of sudden cardiac death (SCD), the interpretation of electrophysiology testing results, and risk-stratification both for asymptomatic individuals and those who have had ablation treatment.

Exercise testing in children with Wolff-Parkinson-White syndrome: what is its value?

This study was conducted to evaluate the accuracy of exercise testing for predicting accessory pathway characteristics in children with Wolff-Parkinson-White (WPW) syndrome. The study enrolled 37 children with WPW syndrome and candidates for invasive electrophysiologic study (EPS). Exercise testing was performed for all the study participants before the invasive study. Data from the invasive EPS were compared with findings from the exercise testing. The sudden disappearance of the delta (Δ) wave was seen in 10 cases (27 %). No significant correlation was found between the Δ wave disappearance and the antegrade effective refractory period of the accessory pathway (AERP-AP) or the shortest pre-excited RR interval (SPERRI). The sensitivity, specificity, and positive and negative predictive values of Δ wave disappearance, based on AERP-AP as gold standard, were respectively 29.4, 80, 71.4, and 40 %. The corresponding values with SPERRI as the gold standard were respectively 23.8, 71.4, 71.4 and 23.8 %. Exercise testing has a medium to low rate of accuracy in detecting low-risk WPW syndrome patients in the pediatric age group.

Electrophysiologic Profile and Results of Invasive Risk Stratification in Asymptomatic Children and Adolescents With the Wolff–Parkinson–White Electrocardiographic Pattern

Background—

Data on the results and clinical effect of an invasive risk stratification strategy in asymptomatic young patients with the Wolff–Parkinson–White electrocardiographic pattern are scarce.

Methods and Results—

Eighty-five consecutive patients aged <18 years with a Wolff–Parkinson–White pattern and persistent preexcitation at maximum exercise undergoing invasive risk stratification were retrospectively studied. Adverse accessory pathway (AP) properties were defined according to currently consented criteria as any of the following: shortest preexcited RR interval during atrial fibrillation/rapid atrial pacing ≤250 ms (or antegrade effective refractory period ≤250 ms if shortest preexcited RR interval was not available) or inducible atrioventricular re-entrant tachycardia. Age at evaluation was median 14.9 years. Eighty-two patients had a structurally normal heart and 3 had hypertrophic cardiomyopathy. A single manifest AP was present in 80, 1 manifest and 1 concealed AP in 4, and 2 manifest APs in 1 patient. Adverse AP properties were present in 32 of 85 patients (37.6%) at baseline and in additional 16 of 44 (36.4%) after isoproterenol. Ablation was performed in 41 of these 48 patients. Ablation was deferred in the remaining 7 for pathway proximity to the atrioventricular node. In addition, 18 of the low-risk patients were ablated based on patient/parental decision.

Conclusions—

Adverse AP properties at baseline were exhibited by 37.6% of the evaluated patients with an asymptomatic Wolff–Parkinson–White preexcitation persisting at peak exercise. Isoproterenol challenge yielded additional 36.4% of those tested at higher risk. Ablation was performed in a total of 69.4% of patients subjected to invasive risk stratification.

Differentiating fasciculoventricular pathway from Wolff-Parkinson-White syndrome by electrocardiography

BACKGROUND

In school-based cardiovascular screening programs in Japan, Wolff-Parkinson-White (WPW) syndrome is diagnosed based on the presence of an electrocardiographic (ECG) delta wave without differentiation from the fasciculoventricular pathway (FVP), although the risk of sudden death is associated only with the former.

OBJECTIVE

The purpose of this study was to differentiate FVP patients among children diagnosed with WPW syndrome by ECG.

METHODS

Children who were diagnosed with WPW syndrome through school screening between April 2006 and March 2008 and had QRS width ≤120 ms were included. Patients with asthma and/or coronary heart disease were excluded. FVP and WPW syndrome were differentiated based on ECG responses to adenosine triphosphate (ATP) injection. Age, PR interval, QRS width, and Rosenbaum classification were compared among patients.

RESULTS

Thirty patients (median age 12.7 years, range 6.5-15.7 years) participated in the study. FVP was diagnosed in 23 patients (76.7%), and WPW syndrome in 7 (23.3%). In Rosenbaum type A patients, all six patients had WPW syndrome, whereas FVP was diagnosed in 23 of 24 and WPW syndrome was diagnosed in 1 of 24 of type B patients. Age, PR interval, and QRS width were not significantly different between the two conditions.

CONCLUSION

ATP stress test was reliable in differentiating FVP from WPW syndrome. Although FVP is considered rare, the results of our study indicate that many WPW syndrome patients with QRS width ≤120 ms may actually have FVP. Patients categorized as type B are more likely to have FVP, whereas type A patients are most likely to have WPW syndrome.

Relation of the utility of exercise testing for risk assessment in pediatric patients with ventricular preexcitation to pathway location

The gradual loss of ventricular preexcitation during exercise stress testing (EST) has an unclear risk of an association with life-threatening arrhythmia and could be related to the accessory pathway (AP) location. We compared the loss of preexcitation during EST with the risk assessment during invasive electrophysiology testing and determined whether the loss of preexcitation correlates with the AP location. We retrospectively reviewed patients aged ≤21 years with ventricular preexcitation who had undergone both EST and an electrophysiology study. The patients were divided into 3 groups: sudden loss (SL), gradual loss (GL), or no loss (NL) of preexcitation during EST. A total of 76 patients were included, with 11 (14%) in the SL group, 18 (24%) in the GL group, and 47 (62%) in the NL group. The SL group demonstrated a longer cycle length with 1-to-1 conduction by way of the AP during incremental atrial pacing compared with the NL group (375 ± 135 ms vs 296 ± 52 ms, p = 0.002), with no difference between the GL and NL groups (325 ± 96 vs 296 ± 52 ms, p = NS). Of the patients with 1-to-1 AP conduction of <270 ms, none (0 of 11) were in the SL group compared to 18 of 47 in the NL group (p = 0.0017), with no significant difference in the GL group (5 of 18) compared to the NL group (p = NS). The patients in the GL group were more likely to have a left-sided AP (14 of 18) than the NL group (17 of 47, p = 0.002) and the SL group (3 of 11, p = 0.002). In conclusion, a sudden loss of preexcitation during an EST predicted a long cycle length with 1-to-1 conduction by way of the AP. Also, the AP conduction characteristics in patients with GL compared to those with NL did not differ, and the GL of preexcitation was more frequently seen in patients with a left-sided AP.

The Wolff–Parkinson–White electrocardiogram pattern in athletes: how and when to evaluate the risk for dangerous arrhythmias. The opinion of the paediatric cardiologist

Although diagnostic assessment and treatment have been described in detail in patients with symptomatic Wolff-Parkinson-White (WPW) syndrome, the management of asymptomatic subjects remains controversial. Usually they are assumed to have a benign prognosis, although they do very occasionally present with ventricular fibrillation (VF) as the first manifestation of the syndrome. Discovering a WPW pattern in a previously asymptomatic athlete on a routine electrocardiogram (ECG) identifies the necessity for more accurate screening tests. However, non-invasive methods (Holter monitoring, exercise treadmill testing) seem to be relatively incomplete for risk stratification, especially for athletes. Current guidelines do not always recommend a routine electrophysiological study (EPS) in patients with an asymptomatic WPW ECG pattern, especially in children younger than 12 years. Individuals who engage in high-risk occupations or those patients who have a pre-excitation pattern which precludes them from following their chosen career or activities may be exceptions. The presence of inducible reciprocating tachycardia during EPS, especially when it triggers atrial fibrillation with short RR interval, can represent a specific risk marker of dangerous arrhythmias.

Role of invasive and noninvasive testing in risk stratification of sudden cardiac death in children and young adults: an electrophysiologic perspective

Sudden cardiac death is a rare, but devastating, event in the young population. Arrhythmia is the mechanism of death in many cases. In addition to clinical history, noninvasive and invasive tests can be used to identify patients who are at risk. Although these tools are not perfect, they can prove valuable if used in proper clinical circumstances. An overview of these tests is presented.

Human clade B serpins (ov-serpins) belong to a cohort of evolutionarily dispersed intracellular proteinase inhibitor clades that protect cells from promiscuous proteolysis

Serpins are unique among the various types of active site proteinase inhibitors because they covalently trap their targets by undergoing an irreversible conformational rearrangement. Members of the serpin superfamily are present in the three major domains of life (Bacteria, Archaea and Eukarya) as well as several eukaryotic viruses. The human genome encodes for at least 35 members that segregate evolutionarily into nine (A-I) distinct clades. Most of the human serpins are secreted and circulate in the bloodstream where they reside at critical checkpoints intersecting self-perpetuating proteolytic cascades such as those of the clotting, thrombolytic and complement systems. Unlike these circulating serpins, the clade B serpins (ov-serpins) lack signal peptides and reside primarily within cells. Most of the human clade B serpins inhibit serine and/or papain-like cysteine proteinases and protect cells from exogenous and endogenous proteinase-mediated injury. Moreover, as sequencing projects expand to the genomes of other species, it has become apparent that intracellular serpins belonging to distinct phylogenic clades are also present in the three major domains of life. As some of these serpins also guard cells against the deleterious effects of promiscuous proteolytic activity, we propose that this cytoprotective function, along with similarities in structure are common features of a cohort of intracellular serpin clades from a wide variety of species.

Should patients with asymptomatic wolff-parkinson-white pattern undergo a catheter ablation?

Many individuals with the Wolff-Parkinson-White electrocardiographic pattern are asymptomatic. Optimal management of these individuals is still a matter of debate. On the one hand, sudden cardiac death from ventricular fibrillation is a rare yet possible outcome in these individuals. On the other hand, there is a low risk of serious complication from electrophysiologic study and ablation. Given that the risk of these competing strategies is comparable, the decision needs to be individualized with considerable patient input.

Propafenone: an effective agent for the management of supraventricular arrhythmias

Propafenone is a sodium channel blocking antiarrhythmic drug. It also has beta-adrenergic, potassium channel, and weak calcium channel blocking activity. The drug is metabolized in the liver with rates dependent on the debrisoquin phenotype. The saturable metabolism results in nonlinear pharmacokinetics. The metabolites retain sodium channel blocking activity but little beta-adrenergic blocking activity. Both controlled and noncontrolled studies have documented its efficacy in a variety of supraventricular arrhythmias. Intravenous propafenone is effective in converting atrial fibrillation to normal sinus rhythm. Chronic oral administration decreases the frequency of recurrence of atrial fibrillation and paroxysmal supraventricular tachycardia. The drug is particularly effective in the Wolff-Parkinson-White syndrome. The drug may produce SA block in patients with underlying sinus node dysfunction. Propafenone has comparatively few noncardiac side effects. It is a useful primary drug or an alternative to more commonly used drugs used for the treatment of supraventricular arrhythmias.

Reversible protective effect of propafenone or flecainide during atrial fibrillation in patients with an accessory atrioventricular connection

In 34 patients with a symptomatic accessory atrioventricular connection the reversible protective effect of orally administered flecainide (300 mg/day) and of propafenone (900 mg/day) in control of ventricular response during atrial fibrillation by exercise was assessed. The study consisted of three sections of 1 week each: an initial treatment phase during which propafenone or flecainide was administered, a drug-free phase, and a period of crossover to treatment with the other drug. At the end of each phase, transesophageal stimulation was performed during physical exercise to induce atrial fibrillation episodes: the goal was to control the persistence of drug effectiveness. At rest, the mean and shortest R-R interval during the period of induced atrial fibrillation in patients who were treated with flecainide or propafenone increased significantly as compared with the drug-free period. On the other hand, at maximum exercise levels no difference in both shortest and mean R-R intervals during atrial fibrillation was observed between patients who were treated with flecainide and those who were treated with propafenone, as well as between flecainide treatment and the drug-free period, whereas a slightly significant difference persisted with propafenone treatment (p less than 0.05). In addition, at maximum exercise levels no significant difference in the number of preexcited QRS complexes among the three treatments was noted. The data from this study suggests that a reversible protective effect against rapid ventricular rate as the result of an episode of atrial fibrillation exists during exercise in patients with a symptomatic accessory atrioventricular connection who are treated with flecainide or propafenone.

Patients with supraventricular tachycardia presenting with aborted sudden death: incidence, mechanism and long-term follow-up

A total of 13 (4.5%) of 290 patients with aborted sudden death had either documented (7; 54%) or strong presumptive evidence of supraventricular tachycardia that deteriorated into ventricular fibrillation. Six (46%) of the 13 had an accessory conduction pathway and either atrial fibrillation (5 patients) or paroxysmal atrioventricular (AV) reentrant tachycardia (1 patient) that deteriorated into ventricular fibrillation. Three patients with AV node reentrant tachycardia and four with atrial fibrillation and enhanced AV node conduction presented with supraventricular arrhythmias that deteriorated into ventricular fibrillation. Patients were treated with medical, surgical or catheter ablative procedures designed to prevent recurrences of supraventricular arrhythmias. Four patients received an implanted automatic defibrillator, but none had an appropriate device discharge. Over a follow-up period of 41.6 +/- 33.6 months, 12 patients are alive without symptomatic arrhythmias. One patient died because of severe chronic lung disease and heart failure. Supraventricular tachycardia was the cause of aborted sudden death in approximately 5% of patients referred for evaluation of sudden cardiac death. Treatment directed at prevention of supraventricular tachycardia was associated with an excellent prognosis. Current treatment techniques appear to obviate the need for automatic defibrillator therapy in these patients.