Influence of age on the potential risk of sudden death in asymptomatic Wolff-Parkinson-White syndrome

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.

Evolution of Clinical and Electrophysiological Data in Children with a Preexcitation Syndrome

BACKGROUND

With ablation, the follow-up of preexcitation syndrome now is difficult to assess. The purpose was to collect data of children with a preexcitation syndrome studied on two separate occasions within a minimal interval of 1 year.

METHODS

This is a retrospective chart review of 47 children initially aged 12 ± 4 years, who underwent two or more invasive electrophysiological studies (EPS) within 1-25 years of one another (6.3 ± 4.8) for occurrence of symptoms or new evaluation.

RESULTS

Among initially symptomatic children (n = 25), four (19%) became asymptomatic and one presented life-threatening arrhythmia. Among asymptomatic children (n = 22), five became symptomatic (22.7%). Anterograde conduction disappeared in seven of 23 children with initially long accessory pathway-effective refractory period, but four of six had still induced atrioventricular reentrant tachycardia (AVRT). AVRT was induced at second EPS in three of 13 asymptomatic preexcitation syndrome with negative initial EPS. There were no spontaneous adverse events in the five children with criteria of malignancy at initial EPS; signs of malignancy disappeared in two. At multivariate analysis, AVRT at initial EPS was the only independent factor of symptomatic AVRT during follow-up. Absence of induced AVRT at initial EPS was the only factor of absence of symptoms and a negative study at the second EPS.

CONCLUSIONS

There were no significant changes of data in children after 6.3 ± 4.8 years of follow-up. Most children with spontaneous/inducible AVRTs at initial EPS had still inducible AVRT at second EPS. Induced AF conducted with high rate has a relatively low prognostic value for the prediction of adverse events.

Influence of advancing age on clinical presentation, treatment efficacy and safety, and long-term outcome of pre-excitation syndromes: a retrospective cohort study of 961 patients included over a 25-year period

OBJECTIVES

There are very little data on pre-excitation syndrome (PS) in the elderly. We investigated the influence of advancing age on clinical presentation, treatment and long-term outcome of PS.

SETTING

Single-centre retrospective study of patient files.

PARTICIPANTS

In all, 961 patients (72 patients ≥60 years (mean 68.5±6), 889 patients <60 years (mean 30.5±14)) referred for overt pre-excitation and indication for electrophysiological study (EPS) were followed for 5.3±5 years. Usual care included 24 h Holter monitoring, echocardiography and EPS. Patients underwent accessory pathway (AP) ablation if necessary.

PRIMARY AND SECONDARY OUTCOME MEASURES

Occurrence of atrial fibrillation (AF) or procedure-induced adverse event.

RESULTS

Electrophysiological data and recourse to AP ablation (43% vs 48.5%, p=0.375) did not significantly differ between the groups. Older patients more often had symptomatic forms (81% vs 63%, p=0.003), history of spontaneous AF (8% vs 3%, p=0.01) or adverse presentation (poorly tolerated arrhythmias: 18% vs 7%, p=0.0009). In multivariable analysis, patients ≥60 years had a significantly higher risk of history of AF (OR=4.2, 2.1 to 8.3, p=0.001) and poorly tolerated arrhythmias (OR=3.8, 1.8 to 8.1, p=0.001). Age ≥60 years was associated with an increased major AP ablation complication risk (10% vs 1.9%, p=0.006). During follow-up, occurrence of AF (13.9% vs 3.6%, p<0.001) and incidence of poorly tolerated tachycardia (4.2% vs 0.6%, p=0.001) were more frequent in patients ≥60 years, although frequency of ablation failure or recurrence was similar (20% vs 15.5%, p=0.52). In multivariable analysis, patients ≥60 years had a significantly higher risk of AF (OR=2.9, 1.2 to 6.8, p≤0.01).

CONCLUSIONS

In this retrospective monocentre study, patients ≥60 years referred for PS work up appeared at higher risk of AF and adverse presentation, both prior and after the work up. These results suggest that, in elderly patients, the decision for EPS and AP ablation should be discussed in light of their suspected higher risk of events and ablation complications. However, these findings should be further validated in future prospective multicentre studies.

Risk Stratification for Arrhythmic Events in Patients With Asymptomatic Pre-Excitation: A Systematic Review for the 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia

Objective—

To review the literature systematically to determine whether noninvasive or invasive risk stratification, such as with an electrophysiological study of patients with asymptomatic pre-excitation, reduces the risk of arrhythmic events and improves patient outcomes.

Methods—

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (all January 1, 1970, through August 31, 2014) were searched for randomized controlled trials and cohort studies examining noninvasive or invasive risk stratification in patients with asymptomatic pre-excitation. Studies were rejected for low-quality design or the lack of an outcome, population, intervention, or comparator of interest or if they were written in a language other than English.

Results—

Of 778 citations found, 9 studies met all the eligibility criteria and were included in this paper. Of the 9 studies, 1 had a dual design—a randomized controlled trial of ablation versus no ablation in 76 patients and an uncontrolled prospective cohort of 148 additional patients—and 8 were uncontrolled prospective cohort studies (n=1594). In studies reporting a mean age, the range was 32 to 50 years, and in studies reporting a median age, the range was 19 to 36 years. The majority of patients were male (range, 50% to 74%), and <10% had structural heart disease. In the randomized controlled trial component of the dual-design study, the 5-year Kaplan-Meier estimates of the incidence of arrhythmic events were 7% among patients who underwent ablation and 77% among patients who did not undergo ablation (relative risk reduction: 0.08; 95% confidence interval: 0.02 to 0.33; P <0.001). In the observational cohorts of asymptomatic patients who did not undergo catheter ablation (n=883, with follow-up ranging from 8 to 96 months), regular supraventricular tachycardia or benign atrial fibrillation (shortest RR interval >250 ms) developed in 0% to 16%, malignant atrial fibrillation (shortest RR interval ≤250 ms) in 0% to 9%, and ventricular fibrillation in 0% to 2%, most of whom were children in the last case.

Conclusions—

The existing evidence suggests risk stratification with an electrophysiological study of patients with asymptomatic pre-excitation may be beneficial, along with consideration of accessory-pathway ablation in those deemed to be at high risk of future arrhythmias. Given the limitations of the existing data, well-designed and well-conducted studies are needed.

[The electrophysiology of Wolff-Parkinson-White in the asymptomatic patient with activity or with high professional risk]

OBJECTIVE

Describe the electrophysiological characteristics in subjects with asymptomatic Wolff-Parkinson-White with sports activities or high professional responsibility.

METHODS

Nineteen subjects, mean age 33 ± 13 years (group A). The electrophysiological characteristics were compared with a matched group with symptomatic WPW (group B).

RESULTS

At baseline the anterograde refractory period and the anterograde conduction 1:1 over the accessory pathway were longer in group A (300 ± 48 ms vs 262 ± 32 ms, p < 0.05 and 355 ± 108 ms vs 307 ± 86 ms, p < 0.05), respectively. None of group A had a anterograde refractory period< 250 ms and 58% showed absence of retrograde conduction over the accessory pathway vs 4% of group B (p < 0.001). Induction of tachycardia was significantly less in group A (5%) than in group B (92%) (p < 0.001). Atrial fibrillation was induced in only one of group A vs 32% of group B (p < 0.001).

CONCLUSION

We confirm the benign electrophysiological characteristics in asymptomatic compared to symptomatic subjects. Poor anterograde conduction along with absence of retrograde conduction explains the low frequency of tachyarrhythmias and would not support the routine investigation of all asymptomatic subjects. But, due to possible consequences, remains the systematic indication for preventive ablation in the subgroup of asymptomatic subjects with sporting activities or high professional responsibility.

[Transesophageal electrophysiological study in non sedated children younger than 11 years with a Wolff-Parkinson-White syndrome]

The electrophysiological evaluation of Wolff-Parkinson-White syndrome (WPW) is recommended in children aged more than five years to detect a risk of life-threatening arrhythmia. The purposes of the study were to determine the feasibility of transesophageal EPS in a child between six and 10 years in out-patient clinic.

METHODS

Electrophysiological study (EPS) was indicated in 22 children, aged six to 10 years, with a manifest WPW either for no documented tachycardia (n=7), unexplained dizziness (n=2) or for a sportive authorization in 10 asymptomatic children. Two of the last children had a history of permanent tachycardia after the birth but were asymptomatic since the age of one year without drugs.

RESULTS

EPS was performed in all children. The main difficulty lied in passing the catheter through the mouth. Programmed stimulation at cycle length of 380 ms was performed in all children to avoid high rates of pacing when the conduction through the accessory pathway (AP) and normal AV system was evaluated. Isoproterenol was not required in five children, because they developed a catecholaminergic sinus tachycardia. The AP refractory period was determined in all children between 200 and 270 ms. Orthodromic reentrant tachycardia (RT) was induced in 11 children, three asymptomatic children (27%), seven complaining of tachycardia and one with syncope. Rapid antidromic tachycardia was induced in this last child with dizziness. Atrial fibrillation was never induced.

CONCLUSIONS

Esophageal EPS can be performed without sedation in a young child six to 10-year-old with a shortened protocol of stimulation, which was capable to clearly evaluate the WPW-related risks.

[Relationships between age and accessory pathway location in Wolff-Parkinson-White syndrome]

BACKGROUND

Radiofrequency ablation of atrioventricular accessory pathway (AP) which is currently used, remains associated with a risk of complete AV block in the case of anteroseptal (AS) location and its indication remains debatable. The purpose of the study was to evaluate the frequency of AS location in Wolff-Parkinson-White syndrome (WPW) and the clinical and electrophysiological data of these patients.

METHODS

Electrophysiologic study (EPS) was performed in 503 pts aged from six to 85 years (35+/-17), 297 men, 206 women, recruited for a patent WPW syndrome. The location of AP was determined on a 12 lead ECG during atrial pacing at maximal preexcitation according to classical criteria. The location was confirmed at EPS. Eleven pts were excluded because the location remained not clearly defined. EPS was indicated for suspected or documented tachycardias (n=264), syncope (n=68) or was systematic in asymptomatic patients (n=171).

RESULTS

AS AP location was identified in 34 patients aged eight to 48 years (7%). Their mean age was younger than the age of remaining population (25+/-13 versus 36+/-17, p<0.001). According to the age, the prevalence of AS location was significantly higher in children and adolescents (14%) than after 40 years (3%) (p<0.01). There was no AS location among 108 patients aged more than 50 years. The maximal rate conducted over AP was lower in patients with AS location than in other locations either in control state (174+/-60 per minute versus 197+/-63 per minute) (p<0.01) or after isoproterenol (206+/-71 versus 248+/-69) (p<0.01). The number of induced reciprocating tachycardia (47% versus 57.5%), atrial fibrillation (15% versus 21%) and malign forms (12% versus 17%) did not differ significantly in patients with AS location and in other patients. Anterograde conduction disappeared spontaneously in three of six patients followed 8+/-1.5 years, and significantly increased in two other patients.

CONCLUSIONS

AS AP location in WPW syndrome was more frequent in children than in adults. The maximal rate conducted over the AP was lower than in other locations. The incidence decreased after 40 years. AS AP location was never noted after 50 years in our population. This disappearance with age should be taken into account for the indications of AS AP ablation.

Wolff-Parkinson-White syndrome in the elderly: clinical and electrophysiological findings

BACKGROUND

Screening for Wolff-Parkinson-White (WPW) syndrome is recommended in children and young adults. The aim of this study was to evaluate the clinical and electrophysiological characteristics of patent WPW syndrome in subjects > or =60 years of age.

METHODS

Four-hundred and fifty-nine consecutive patients with WPW syndrome, aged 8-80 years, were recruited; 32 (7%) of these patients were > or =60 years of age. The clinical, electrophysiological and therapeutic data for these patients were evaluated.

RESULTS

Sixteen men and 16 women, aged 60-81 years (67+/-4.5), were admitted for resuscitated sudden death (1), rapid atrial fibrillation (4), syncope (4), or junctional tachycardia (13); 10 patients were asymptomatic (10). Left lateral bundles of Kent were detected more frequently in patients over 60 years (56%) than in those<60 years of age (40.5%). Reciprocal tachycardia was induced in 58% of subjects<60 years of age and 53% of those > or =60 years old (difference not significant); atrial fibrillation was more frequent in subjects > or =60 years of age (37.5% vs. 19%) (p<0.05). The incidence of malignant forms of WPW syndrome was identical in older and younger subjects. Ablation of the accessory pathway was indicated 18 times; effective ablation of a left bundle of Kent required a second intervention more often in patients > or =60 years of age (22% vs. 5%) (p<0.05).

CONCLUSION

WPW syndrome is not uncommon in subjects over 60 years of age (7%). Left lateral accessory pathways, that have similar conduction properties to those in much younger subjects, are common. Ablation of the bundle of Kent is often difficult but is indicated in symptomatic subjects or those with more serious forms of WPW syndrome.

[Respective interest of two techniques of electrophysiological study in patient without heart disease]

Electrophysiologic study (EPS) frequently is required to assess the prognosis of asymptomatic Wolff-Parkinson-White syndrome (WPW) or to prove the nature of no documented tachycardia. EPS usually is performed by intracardiac route and hospitalization is required. Similar data are given by an EPS performed by oesophageal route during a consultation. The purpose of the study was to evaluate the cost of both techniques in France. Transesophageal EPS was performed during a consultation in 100 patients with asymptomatic WPW syndrome and 100 patients with no heart disease, complaining of no documented tachycardias with abrupt beginning and end, suggesting a paroxysmal junctional re-entrant tachycardia (PJRT). The cost of transesophageal study including isoproterenol infusion is 127.75 euros. The cost of intracardiac EPS is at least 1460 euros, cost of hospitalization during only one day.

RESULTS

In patients with WPW syndrome, 15 had a potentially malignant form with the induction of a tachycardia conducted through the accessory pathway at a high rate (> 240/min in control state, > 300/min with isoproterenol); radiofrequency catheter ablation was indicated in a second time. In the group with no documented tachycardia, PJRT was induced in 30 patients and indication of ablation was discussed. In other 155 patients with either a benign form of WPW syndrome or with a tachycardia unrelated to a PJRT, hospitalization was not required; in these patients, intracardiac study performed during one day of hospitalization would have costed 226,300 Euros. The cost for the esophageal EPS and a similar diagnosis was 19,801 Euros, with a save money of 206,499 Euros. In 45 patients in whom hospitalization was indicated in a second time to perform catheter ablation of the arrhythmia, the cost related to esophageal EPS was 5749 Euros. In the total group, considering the final diagnosis and the need of hospitalization in 45 patients, the save money related to the use of esophageal EPS was 206,499 E-5749 E = 200,750 euros.

CONCLUSIONS

We should take into account the cost studies, when various techniques could be used for a similar diagnosis. There are important differences in the cost of diagnostic methods and it is easy to decrease this cost.

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.

Electrophysiological evaluation of asymptomatic ventricular pre-excitation in children and adolescents

BACKGROUND

Diagnostic assessment and treatment have been described in detail in symptomatic WPW syndrome, but little information exists about significance and prognosis of an incidentally found ventricular pre-excitation (VPE) in asymptomatic children. The aim of the study was to evaluate, retrospectively, the role of electrophysiological study (EPS) in the assessment of the arrhythmic risk in asymptomatic patients with VPE.

MATERIAL AND METHODS

Sixty-two asymptomatic children and adolescents (38 M/24 F, aged 9.8+/-5.1 years) referred to our Division between 1996 and 2002 for an incidentally found VPE underwent an EPS for arrhythmic risk stratification. The following parameters were examined: anterograde effective refractory period of the accessory pathway (AP), the 1-to-1 conduction over the AP, the inducibility of atrio-ventricular re-entrant tachycardia (AVRT) and the inducibility of atrial fibrillation (AF) with measurement of minimal RR between two consecutive preexcitated QRS complexes, the average RR interval of all cycles, and the percentage of preexcitated QRS complexes.

RESULT

During the EPS, 36 patients (58.1%) experienced sustained SVT. The tachycardia was initiated in the basal state in 22 patients and after isoproterenol in the other 14. Orthodromic AVRT (cycle length 305.9+/-48.5 ms) was recorded in 29 patients. In three patients, both orthodromic and antidromic AVRT were recorded, with different cycle length (CL). Antidromic AVRT alone (CL 239.5+/-13.7 ms) was recorded in four patients. AF was recorded in nine patients: in six patients, it was recorded after the induction of orthodromic or antidromic AVRT, in the other three cases AF was the first and only arrhythmic event. The minimal RR between two consecutive pre-excitated QRS ranged between 250-230 ms (mean 237.5+/-9.6 ms). In the 26 patients who presented no induced sustained tachycardia in the EPS, the 1:1 conduction over the AP ranged between 210 and 600 ms (mean 279.6+/-75.2 ms).

CONCLUSIONS

Electrophysiological evaluation remains the gold standard for assessing risk of life-threatening arrhythmias in patients with VPE. However, a high proportion of healthy children and adolescents with VPE can experience sustained AVRT and/or AF during EPS. These results raise questions about the necessity of an aggressive treatment approach to prevent those "rare" cases of sudden death.

Influence of age on atrial fibrillation inducibility

The prevalence of AF is known to increase in the elderly. Some electrophysiological changes were reported in these patients, but the effects of age on AF inducibility and other electrophysiological signs associated with atrial vulnerability are unknown. The purpose of the study was to evaluate the effects of age on atrial vulnerability and AF induction. The study consisted of 734 patients (age 16-85 years, mean 61 +/- 15 years) without spontaneous AF who were admitted for electrophysiological study. Study was indicated for dizziness or ventricular tachyarrhythmia. Programmed atrial stimulation was systematically performed. One and two extrastimuli were delivered in sinus rhythm and atrial driven rhythms (600, 400 ms). Univariate and multivariate analysis of several clinical and electrophysiological data were performed. AF inducibility, defined as the induction of an AF lasting > 1 minute, was paradoxically and significantly decreased in elderly (> 70 years) patients compared to younger patients (< 70 years) (P < 0.01). AF inducibility was present in 40% of 62 patients < 40 years, 39% of 99 patients age 40-50 years, 37% of 130 patients age 50-60 years, 38% of 222 patients age 60-70 years, and only 28% of 221 patients > 70 years. There was no significant correlation with the sex, the presence of dizziness, the presence or not of an underlying heart disease, the left ventricular ejection fraction, and the presence of salvos of atrial premature beats on 24-hour Holter monitoring. There was a significant correlation with a longer atrial effective refractory period in the elderly (226 +/- 41 ms) than in younger patients (208 +/- 31 ms) (P < 0.001). Other electrophysiological parameters of atrial vulnerability did not change significantly. Increased atrial refractory period and age >70 years were independent factors of decreased AF inducibility. Programmed atrial stimulation should be interpreted cautiously before the age of 70 years. AF induction is facilitated by the presence of a short atrial refractory period in these patients. Surprisingly, AF inducibility decreases in patients > 70 years because their atrial refractory period increases. Therefore, increased AF prevalence in these patients should be explained by nonelectrophysiological causes.

Atrial fibrillation with a very rapid ventricular response as the first clinical arrhythmia in a 76-year-old man

The interest of electrohysiological study for the prognostic evaluation of asymptomatic Wolff-Parkinson-White (WPW) syndrome remains controversial. We report the case of an asymptomatic 67-year-old man without heart disease in whom a type A WPW syndrome was noted. Because the WPW was unchanged during exercise testing, transesophageal EPS was performed. In basal state, 1/1 conduction through the Kent bundle was noted up to a rate of 210 beats/min. After infusion of 30 microg of isoproterenol, atrial pacing was associated with a 1/1 conduction throughout the Kent bundle at a rate at 300 beats/min and induced rapid atrial fibrillation which was stopped by flecainide. No treatment was indicated. Nine years later, at age 76, the patient developed syncope related to rapid atrial fibrillation requiring cardioversion. In conclusion, the occurrence of a potentially lethal supraventricular tachyarrhythmia in a previously asymptomatic patient with WPW syndrome might be encountered in elderly patients. Transesophageal electrophysiological evaluation is a useful means to predict this risk.

Usefulness of invasive electrophysiologic testing to stratify the risk of arrhythmic events in asymptomatic patients with Wolff-Parkinson-White pattern: results from a large prospective long-term follow-up study

OBJECTIVES

The aim of this study was to assess in a large cohort of asymptomatic subjects with Wolff-Parkinson-White (WPW) pattern the usefulness of invasive electrophysiologic testing (EPT) in predicting the occurrence of arrhythmic events over a five-year follow-up.

BACKGROUND

Sudden death may be the first clinical manifestation of the WPW syndrome in previously asymptomatic patients. Serial EPTs have been proposed to identify patients at risk.

METHODS

A total of 212 consecutive asymptomatic WPW patients were enrolled after a baseline EPT; patients were followed for five years, and 162 patients (115 noninducible and 47 inducible) patients underwent a second EPT.

RESULTS

After a mean follow-up of 37.7 months, 33 patients became symptomatic. Of the 115 noninducible patients, 18.2% lost anterograde accessory pathway (AP) conduction, 30% retrograde AP conduction, and only 4 (3.4%) developed symptomatic supraventricular tachycardia (SVT). Of the 47 inducible patients, 25 with sustained atrioventricular reciprocating tachycardia (AVRT) and atrial fibrillation (AF), and 4 with nonsustained AVRT and AF became symptomatic for SVT (n = 21) and AF (n = 8). They were younger, had shorter AP anterograde refractory periods, and multiple APs compared to patients who remained asymptomatic (for all comparisons, p < 0.0001). Of the eight patients with symptomatic episodes of AF and inducible sustained AF, two had a resuscitated cardiac arrest and one died suddenly; all three patients were inducible for AVRT and AF and had multiple APs.

CONCLUSIONS

In asymptomatic WPW subjects, EPT may be a valuable tool to stratify the risk of symptomatic and fatal arrhythmic events.