Author + information
- Received June 4, 1985
- Revision received July 30, 1985
- Accepted August 14, 1985
- Published online January 1, 1986.
- William G. O'Callaghan, MB, MRCPIa,
- Paul G. Colavita, MD,
- G. Neal Kay, MD,
- Kenneth A. Ellenbogen, MD,
- Marcel R. Gilbert, MD and
- Lawrence D. German, MD, FACC
- ↵aAddress for reprints: William G. O'Callaghan, MB, Box 3860, Duke University Medical Center, Durham, North Carolina 27710.
Accessory pathway electrograms are rarely recorded in patients with Wolff-Parkinson-White syndrome. In one patient, during electrophysiologic study, simultaneous local ventricular (V) accessory pathway (AP) and atrial (A) deflections were recorded during bipolar catheter endocardial mapping over the pathway. Analysis of changes in electrographic intervals during performance of the ventricular extrastimulus technique allowed characterization of the retrograde conduction properties of the pathway. As coupling intervals were decreased, an initial increase was seen in the AP2A2interval with subsequent ventriculoatrial block between the accessory pathway and atrium. When coupling intervals were further decreased, the V2AP2interval lengthened with ultimate block between the ventricle and accessory pathway. These findings support the concept of impedance mismatch as the cause of conduction block in accessory pathways with the distal junction of the accessory pathway being the most vulnerable.
- Received June 4, 1985.
- Revision received July 30, 1985.
- Accepted August 14, 1985.
- American College of Cardiology Foundation