Is isoproterenol really required during electrophysiological study in patients with Wolff-Parkinson-White syndrome?
Abstract
We have studied the results of electrophysiological study (EPS) in patients with Wolff-Parkinson-White syndrome (WPW) and spontaneous adverse clinical presentation and determined whether isoproterenol added incremental value.
METHODS:
EPS was performed in 63 patients with WPW and adverse clinical presentation at baseline. EPS was repeated after infusion of isoproterenol in 37 patients, including 25 without criteria for a malignant form at baseline.
RESULTS:
Atrioventricular orthodromic tachycardia was induced 44%, antidromic tachycardia in 11%, atrial fibrillation (AF) in 68% at baseline. At baseline EPS, criteria for a malignant form (AF induction and shortest CL <250 ms) were noted in 60%; tachycardia was not inducible in 16%. All the patients met the criteria for a malignant form after isoproterenol.
CONCLUSIONS:
EPS at baseline missed 16% of patients at risk of life-threatening arrhythmias who had no inducible tachyarrhythmia and 40% without classical criteria for malignant form.