Linking: A Mechanism of Intermittent Preexcitation in the Wolff-Parkinson-White Syndrome |
| |
Authors: | HOLLY R MIDDLEKAUFF WILLIAM G STEVENSON THOMAS S KLITZNER |
| |
Institution: | The Divisions of Cardiology and Pediatric Cardiology, Departments of Medicine and Pediatrics, UCLA School of Medicine, Los Angeles, California |
| |
Abstract: | MIDDLEKAUFF, H.R., ET AL.: Linking: A Mechanism of Intermittent Preexcitation in the Wolff-Parkinson-White Syndrome. Intermittent preexcitation in the Wolff-Parkinson-White syndrome has been equated with a long accessory pathway refractory period and long R-R interval between preexcited beats in atrial fibrillation and therefore a low risk for sudden death. A case of Wolff-Parkinson-White syndrome in which preexcitation became intermittent following procainamide infusion, with only moderate prolongation of the accessory pathway refractory period but marked prolongation of the shortest preexcited R-R interval in atrial fibrillation, is described. Programmed ventricular and atrial stimulation demonstrated that intermittent preexcitation was caused by concealed conduction producing a linking phenomenon, facilitated by the antiarrhythmic drug. Linking due to concealed retrograde penetration of a propagated impulse into the accessory pathway may contribute to the disparity between accessory pathway refractory period and shortest preexcited R-R interval in atrial fibrillation in some patients and may be a confounding factor in the interpretation of noninvasive tests of accessory pathway conduction. |
| |
Keywords: | Wolff-Parkinson-White preexcitation linking concealed conduction |
|
|