Sudden death and ventricular preexcitation: is it necessary to treat the asymptomatic patients?

Currently, asymptomatic ventricular preexcitation, which has been put at rest for many decades, remains a clinical challenge as there are no predictors of sudden death, which can be the first clinical presentation of the syndrome. Identification of risk factors for sudden death is important, considering the availability of a definitive treatment. Now, as radiofrequency catheter ablation of accessory pathways has reported success rates approaching 100 percent without major complications in many centers worldwide, it becomes unacceptable that even one asymptomatic individual with WPW will die or will experience life-threatening arrhythmic events. In our extensive experience a short anterograde refractory period of accessory pathways, inducibility of sustained tachyarrhythmias and the presence of multiple accessory pathways are the strongest predictors of life-threatening arrhythmias and sudden death. Therefore, it is not yet justified that, after an incidental diagnosis of WPW syndrome has been made, no risk stratification by invasive testing is done. Subjects at high risk, particularly if young or adolescent, should be identified and then ablated in the same session as they can develop lethal arrhythmic events within a few years and this is our current practice. Recently, we sent a questionnaire to investigate clinical practices over a large number of centers around the world about asymptomatic ventricular preexcitation. A total of 100 replies were received and the results demonstrate that there is worldwide agreement in performing invasive electrophysiologic testing and prophylactic ablation in selected subjects. These findings provide strong evidence to revisit current guidelines, which appropriately in the absence of evidence had been conservative.