Usefulness of Adenosine Testing in the Differential Diagnosis Between Fasciculoventricular Pathways and Wolff-Parkinson-White-type Ventricular Preexcitation

Abstract

Background: The diagnosis of Wolff-Parkinson-White-type ventricular preexcitation on the surface electrocardiogram is generally easy. However, in patients with minimal or subtle electrocardiographic manifestations, the differential diagnosis with other types of preexcitation, as fasciculoventricular fibers, may be difficult. Adenosine testing is a useful tool for that purpose. Objective: The aim of this study is to describe our experience with adenosine testing in the differential diagnosis of patients with minimal ventricular preexcitation. Methods: Of 313 consecutive patients with diagnosis of Wolff-Parkinson-White, 28 patients with minimal preexcitation on the electrocardiogram that questioned the diagnosis were analyzed. Results: Adenosine testing produced transient first degree, second degree and complete atrioventricular block without changing the ventricular activation pattern, ruling out Wolff-Parkinson-White syndrome. Twenty patients underwent an electrophysiologic study which confirmed the diagnosis of fasciculoventricular pathways in 16 cases. Conclusion: In patients with suspected Wolff-Parkinson-White ventricular preexcitation, adenosine testing proved to be an efficient and safe tool to establish or rule out the diagnosis.