Author + information
- Received August 11, 1986
- Revision received December 17, 1986
- Accepted January 9, 1987
- Published online August 1, 1987.
- ↵‡Address for reprints: Rodolphe Ruffy, MD, Jewish Hospital at Washington University Medical Center, Cardiology Division, 216 S. Kingshigh-way, St. Louis, Missouri 63110.
Electrophysiologic studies were performed on a 49 year old woman who had paroxysmal nonreentrant supraventricular tachycardia due to simultaneous anterograde conduction through dual atrioventricular (AY) node pathways. Slow pathway conduction was inversely related to the preceding sinus cycle length and fast pathway conduction was determined by the Hs-A interval (measured from the His potential due to slow pathway conduction to the onset of the subsequent atrial electrogram).
Major determinants of sustained simultaneous anterograde fast and slow pathway conduction during sinus rhythm were 1) a retrograde unidirectional block in both fast and slow pathways, and 2) a critical conduction delay in the slow pathway and a long enough Hs-A interval to allow sequential conduction of impulse from both pathways. Flecainide was successful in preventing recurrences of the tachycardia by eliminating slow pathway conduction during long-term follow-up.
- Received August 11, 1986.
- Revision received December 17, 1986.
- Accepted January 9, 1987.
- American College of Cardiology Foundation