EP WIRE
Sudden cardiac death stratification in asymptomatic ventricular preexcitation
1 Electrophysiology, Cardiovascular Department, Ospedali Riuniti di Bergamo, Largo Barozzi 1, 24128 Bergamo, Italy; 2 Division of Cardiology, University Hospital Magdeburg, Magdeburg, Germany
* Corresponding author. Email: fcantu{at}ospedaliriuniti.bergamo.it (F.C.); andreas.goette{at}medizin.uni-magdeburg.de (A.G.)
 |
Abstract |
|---|
 Top Abstract IntroductionResultsDiscussionReferences |
|---|
The second survey deals with risk stratification in subjects, either adults or children, with ventricular preexcitation and no symptoms in their history. Current European electrophysiological practice is still variable among different centres. Although invasive stratification is still part of the practical management of asymptomatic subjects, a not negligible proportion of physicians do not completely rely on cut off values provided in the literature, proceding to ablation irrespective of the stratification process. These concerns are mainly due to the perception of lack of strong evidence that, according to the majority of centres, is still needed.
Key Words: Sudden death, Preexcitation
|
Introduction |
|---|
|
TopAbstractIntroductionResultsDiscussionReferences |
|---|
Wolff–Parkinson–White (WPW) syndrome refers to the association of manifest preexcitation and symptoms due to re-entrant arrhythmias. One of the more dreaded clinical presentations of the syndrome is sudden cardiac death (SCD).
In symptomatic patients, a risk of ventricular fibrillation of 2.2% has been estimated, whereas in asymptomatic patients, this risk is 
1 per 1000 patient/years.1
,2 Based upon this epidemiological data, the management of asymptomatic preexcitation presents a challenge.
Traditionally, SCD risk stratification in this context has mainly focused on the estimation of the accessory pathway's (AP) refractory period. Three (non-invasively obtained) observations have been advocated: (i) sudden disappearance of preexcitation during exercise,3 (ii) intermittent preexcitation, (iii) disappearance of preexcitation with procainamide infusion.4 This strategy has generated criticism in terms of its predictivity.5 In particular, it has been shown to be particularly poor in the paediatric population due to fast atrioventricular node conduction confounding meaningful interpretation of delta wave changes during exercise.6 More direct and perhaps accurate estimation of the AP properties may be assessed by invasive (pervenous) or semi-invasive (transoesophageal) electrophysiological testing. A cut-off value between 250 and 270 ms of anterograde effective refractory period (AERP) and a minimum preexcited RR interval during atrial fibrillation of 240 ms (200 ms during isoproterenol infusion) have been suggested in the literature.7 This approach still offers a quite low predictive value, particularly in asymptomatic patients. Overall, the pivotal role of invasive stratification, in the paediatric population in particular, is confirmed by survey data (part of the Pediatric Radiofrequency ablation registry), which shows that most participating centres relied on invasive testing using the above parameters to stratify asymptomatic patients.8
The aim of this study was to outline the current clinical practice in European centres dealing with asymptomatic adults and children with evidence of preexcitation.
|
Results |
|---|
|
TopAbstractIntroductionResultsDiscussionReferences |
|---|
Thirty-five European centres provided answers to the questionnaire, roughly half of them (52.8%) treat both adult and children; 69.4% of the centres routinely submit asymptomatic patients with preexcitation to arrhythmic risk stratification, leading to ablation where it is deemed necessary. Those centres that do not, either perform ablation in all patients or do not further assess asymptomatic preexcitation at all (16 and 8.4%, respectively). About 5.6% of the centres perform stratification only in children. The first-line risk stratification approach is invasive in 44.4% of responding centres, whereas the remaining collect preliminary results from a non-invasive evaluation mainly performed by means of ergometric testing (61.1%) and Holter monitoring (47.2%). Non-invasive evaluation is applied as the first-line approach in 33.3% of the centres and is applied in selected cases according to age and clinical history (5.6%), in those who play sports (2.8%) or in those with constant preexcitation. Pervenous electrophysiological testing is performed routinely in all patients in 37.1% of the centres, but only according to clinical history or age in 28.6%, according to results of non-invasive tests in 14.3%, or only in those who play sport in 5.7%. This breakdown holds true for the paediatric population if those centres that do not have a paediatric practice are excluded. A transoesophageal electrophysiological study is considered as an alternative only by a minority of centres (8%), according to age or weight of the patient. Regardless of how the study is carried out, the EP parameters that are taken into consideration are effective refractory period of the accessory pathway (AERP <240 ms) (31.45%), minimum RR interval (20%), atrial fibrillation induction (2.9%), or a combination of the former (45.7%).
Finally, 88.6% of the participating centres said that the evidence base that currently exists is insufficient to guide clinical practice.
|
Discussion |
|---|
|
TopAbstractIntroductionResultsDiscussionReferences |
|---|
The proper management of asymptomatic ventricular preexcitation remains a matter of debate. A previous US survey carried out among a paediatric population showed homogeneous behaviour among participating centres: 86% of the electrophysiologists routinely perform pervenous EP study aimed at selecting patients for ablation. Our European survey confirms that selection of patients based upon stratification of arrhythmic risk is still a common EP practice, although there is a range of clinical approaches. At one extreme, 16.7% of the centres perform ablation in all patients with preexcitation, and at the other, 8.3% do nothing in asymptomatic patients or perform pervenous electrophysiological study only as a second step following the results of non-invasive stratification. Only a small number of electrophysiologist use transoesophageal electrophysiological testing.
Recent work has focused on the upstream causes of arrhythmic death, i.e. inducibility of supraventricular arrhythmias. In a prospective evaluation of a paediatric cohort, Pappone et al.9,10 found that inducibility per se conveyed a high arrhythmic risk, even though the event rate reported in that work was perhaps unexpectedly high compared with that measured in a single-large cohort study. More recently, the same authors, in a prospective follow-up of asymptomatic children, showed that short AERP and multiple accessory pathways independently predicted life-threatening arrhythmic events.11 In keeping with this recent evidence, the boundary parameters thought to discriminate between high- and low-risk patients are: AERP <240 ms and short RR interval in atrial fibrillation. Interestingly, none of the centres considers arrhythmia induction per se to be a relevant criterion.
Despite some new evidences from observational studies,11 most centres (88.6%) still believe that large prospective studies are needed to inform optimal management of asymptomatic ventricular preexcitation syndrome.
Conflict of interest: none declared.
|
References |
|---|
|
TopAbstractIntroductionResultsDiscussionReferences |
|---|
[1] Berkman NL, Lamb LE. The Wolff Parkinson White electrogram. A follow up study of five to twenty-eight years. N Engl J Med (1968) 278:492–4.[Web of Science][Medline]
[2] Timmermans C, Smeets JL, Rodriguez LM, et al. Aborted sudden death in the Wolff-Parkinson-White syndrome. Am J Cardiol (1995) 76:492–4.[CrossRef][Web of Science][Medline]
[3] Wellens HJ, Pappone C, Santinelli V, et al. When to perform catheter ablation in asymptomatic patients with a Wolff-Parkinson-White electrocardiogram. Circulation (2005) 112:2201–16.
[4] Chimienti M, Moizi M, Klersy C. A modified ajmaline test for prediction of the accessory pathway in the pathway in the Wolff-Parkinson-White syndrome. Am J Cardiol (1987) 59:164–5.[CrossRef][Web of Science][Medline]
[5] Gaita F, Giustetto C, Ricardi R, et al. Stress and pharmacological tests as message to identify patients with Wolff-Parkinson-White syndrome. Am J Cardiol (1989) 64:487–90.[CrossRef][Web of Science][Medline]
[6] Brembilla-Perrot B, Chometon F, Groben L, et al. Interest of non-invasive and semiinvasive testing in asymptomatic children with pre-excitation syndrome. Europace (2007) 9:837–43.
[7] Klein GJ, Bashore TM, Sellers TD, et al. Ventricular fibrillation in the Wolff-Parkinson-White syndrome. N Engl J Med (1979) 301:1080–5.[Abstract]
[8] Campbell R, Strieper MJ, Patricio A, et al. Survey of current practice of pediatric electrophysiologist for asymptomatic Wolff-Parkinson-White syndrome. Pediatrics (2003) 111:e245–7.
[9] Pappone C, Santinelli V, Rosanio S, et al. Usefulness of invasive electrophysiologic testing to stratify the risk of arrhythmic events in asymptomatic patients with Wolff-Parkinson-White pattern: result from a large prospective long term follow up study. J Am Coll Cardiol (2003) 41:239–44.
[10] Pappone C, Manguso F, Santinelli V, et al. Radiofrequency ablation in children with asymptomatic Wolff-Parkinson-White syndrome. N Engl J Med (2004) 351:1197–205.
[11] Santinelli V, Radinovic A, Manguso F, et al. The natural history of asymptomatic ventricular pre-excitation. A long term prospective follow up study of 184 asymptomatic children. J Am Coll Cardiol (2009) 53:275–80.
CiteULike 
Connotea 
Del.icio.us What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||