[Refiles story posted May 15, 2012 as 20120515clin002, with no changes to text, to fix a technical problem.]
NEW YORK (Reuters Health) – Pooled data show low rates of sudden cardiac death and supraventricular tachycardia in patients with asymptomatic Wolff-Parkinson-White (WPW) syndrome.
The 20 studies in a recent meta-analysis involved 1,869 patients with asymptomatic WPW patterns on electrocardiography (ECG) and 11,722 person-years of follow-up, the Canadian researchers reported April 24th online in Circulation.
The estimated risk of sudden cardiac death was less than 2.5 per 1,000 person-years of follow-up, Dr. Manoj N. Obeyesekere told Reuters Health by email. The risk for supraventricular tachycardia was 2.5 per 1,000 person-years.
According to the report by Dr. Obeyesekere of the University of Western Ontario, London and colleagues, the prevalence of WPW pre-excitation on ECG is as high as 0.3%.
They say that in symptomatic patients with WPW syndrome, the risk of sudden cardiac death is approximately 0.25% per year or 3-4% over a lifetime. In these patients, ablation benefits outweigh the procedural risks. The benefit of ablation is less clear in asymptomatic individuals and current guidelines do not favor an invasive approach.
To investigate further, the team conducted the meta-analysis. But while risks of sudden death and supraventricular tachycardia were low, Dr. Obeyesekere, said, “Children had a numerically higher (sudden cardiac death) event rate, warranting a higher index of suspicion during follow-up.”
Patients with WPW most susceptible to sudden cardiac death are symptomatic. Thus, the investigators point out, “the evolution of the clinical status from an asymptomatic state to symptoms likely portends a higher risk for sudden cardiac death and these patients should seek medical review.”
The low incidence of the primary outcomes, they add “argues against routine invasive management in most asymptomatic patients with the Wolff-Parkinson-White ECG pattern.”
“When considering management options,” Dr. Obeyesekere concluded, “a carefully informed patient (or parent) and physician needs to choose between the arrhythmic risk and the success and complication rates associated with electrophysiological study. The occurrence of symptoms likely portends a higher risk, and these patients should be offered electrophysiological study.”